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Sample records for incentives cellulosic ethanol

  1. Cellulosic ethanol

    DEFF Research Database (Denmark)

    Lindedam, Jane; Bruun, Sander; Jørgensen, Henning

    2010-01-01

    Background Variations in sugar yield due to genotypic qualities of feedstock are largely undescribed for pilot-scale ethanol processing. Our objectives were to compare glucose and xylose yield (conversion and total sugar yield) from straw of five winter wheat cultivars at three enzyme loadings (2.......5, 5 and 10 FPU g-1 dm pretreated straw) and to compare particle size distribution of cultivars after pilot-scale hydrothermal pretreatment. Results Significant interactions between enzyme loading and cultivars show that breeding for cultivars with high sugar yields under modest enzyme loading could...... be warranted. At an enzyme loading of 5 FPU g-1 dm pretreated straw, a significant difference in sugar yields of 17% was found between the highest and lowest yielding cultivars. Sugar yield from separately hydrolyzed particle-size fractions of each cultivar showed that finer particles had 11% to 21% higher...

  2. Fulton Cellulosic Ethanol Biorefinery

    Energy Technology Data Exchange (ETDEWEB)

    Sumait, Necy [BlueFire Ethanol, Irvine, CA (United States); Cuzens, John [BlueFire Ethanol, Irvine, CA (United States); Klann, Richard [BlueFire Ethanol, Irvine, CA (United States)

    2015-07-24

    Final report on work performed by BlueFire on the deployment of acid hydrolysis technology to convert cellulosic waste materials into renewable fuels, power and chemicals in a production facility to be located in Fulton, Mississippi.

  3. Production of ethanol from cellulose (sawdust)

    OpenAIRE

    Otulugbu, Kingsley

    2012-01-01

    The production of ethanol from food such as corn, cassava etc. is the most predominate way of producing ethanol. This has led to a shortage in food, inbalance in food chain, increased food price and indirect land use. This thesis thus explores using another feed for the production of ethanol- hence ethanol from cellulose. Sawdust was used to carry out the experiment from the production of ethanol and two methods were considered: SHF (Separate Hydrolysis and Fermentation) and SSF (Simultaneous...

  4. Cellulosic ethanol: status and innovation

    Energy Technology Data Exchange (ETDEWEB)

    Lynd, Lee R.; Liang, Xiaoyu; Biddy, Mary J.; Allee, Andrew; Cai, Hao; Foust, Thomas; Himmel, Michael E.; Laser, Mark S.; Wang, Michael; Wyman, Charles E.

    2017-06-01

    Although the purchase price of cellulosic feedstocks is competitive with petroleum on an energy basis, the cost of lignocellulose conversion to ethanol using today’s technology is high. Cost reductions can be pursued via either in-paradigm or new-paradigm innovation. As an example of new-paradigm innovation, consolidated bioprocessing using thermophilic bacteria combined with milling during fermentation (cotreatment) is analyzed. Acknowledging the nascent state of this approach, our analysis indicates potential for radically improved cost competitiveness and feasibility at smaller scale compared to current technology, arising from (a) R&D-driven advances (consolidated bioprocessing with cotreatment in lieu of thermochemical pretreatment and added fungal cellulase), and (b) configurational changes (fuel pellet coproduction instead of electricity, gas boiler(s) in lieu of a solid fuel boiler).

  5. Bioconversion of cellulose to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Hahn-Haegerdal, B; Mandenius, C F; Mattiasson, B; Nilsson, B; Axelsson, J P; Hagander, P

    1985-06-20

    Enzymatic hydrolysis of steam pretreated sallow gives highest yields of soluble sugars when hemicellulose is degraded already in the pretreatment step. The steam pretreatment equipment is rebuilt so that 75 g (dry matter) material instead of 7 g can be treated each time. The cellulose production has been increased 123% by the utilization of aqueous two-phase systems as compared to regular growth medium. The cellulase activity per gram of cellulose has been increased from 42 FPU in regular growth medium to 156 FPU in aqueous two-phase systems. Crude dextran can be used for enzyme production. Enzyme recovery up to 75% has been achieved by combining aqueous two-phase technique with membrane technique. Using the enzyme glucose isomerase in combination with S. cerevisiae theoretical yields in pentose fermentations have been achieved, with a product concentration of 60 g/L and a productivity of 2 g/L x h. Yeast and enzyme can be recirculated using membrane technique. Computer simulation shows that the rate equation for enzymatic hydrolysis with respect to inhibiting sugar concentrations can be used to interpolate with respect to sugar concentrations. Computer simulations show that hydrolysis experiments should focus on high substrate concentrations (>10%) using fed-batch technique and enzyme concentrations in the range of 2-8% in relation to substrate dry matter. The combined 'flow injection analysis', FIA, and enzyme reactor probe has been adapted to enzymatic saccarifications of sodium hydroxide pretreated sallow. The gas membrane sensor for ethanol has been utilized in simultaneous saccharification and fermentation of sodium hydroxide pretreated sallow. A literature study concerning pervaporation for ethanol up-grading has been made.(Author).

  6. African perspective on cellulosic ethanol production

    DEFF Research Database (Denmark)

    Bensah, Edem Cudjoe; Kemausuor, Francis; Miezah, Kodwo

    2015-01-01

    A major challenge to commercial production of cellulosic ethanol pertains to the cost-effective breakdown of the complex and recalcitrant structure of lignocellulose into its components via pretreatment, the cost of enzymes for hydrolysis and fermentation, and the conversion rate of C5 sugars...... to ethanol, among others. While the industrialized and some emerging countries are gradually breaking grounds in cellulosic ethanol, most African countries have made little effort in research and development even though the continent is rich in lignocellulosic biomass. The paper estimates residues from...... widely available crops and municipal waste and determines their respective theoretical ethanol potential (around 22 billion litres annually). It further reviews stages involved in the production of cellulosic ethanol, focussing on processing methods that can be adapted to current situation in most...

  7. [Insights into engineering of cellulosic ethanol].

    Science.gov (United States)

    Yue, Guojun; Wu, Guoqing; Lin, Xin

    2014-06-01

    For energy security, air pollution concerns, coupled with the desire to sustain the agricultural sector and revitalize the rural economy, many countries have applied ethanol as oxygenate or fuel to supplement or replace gasoline in transportation sector. Because of abundant feedstock resources and effective reduction of green-house-gas emissions, the cellulosic ethanol has attracted great attention. With a couple of pioneers beginning to produce this biofuel from biomass in commercial quantities around the world, it is necessary to solve engineering problems and complete the economic assessment in 2015-2016, gradually enter the commercialization stage. To avoid "competing for food with humans and competing for land with food", the 1st generation fuel ethanol will gradually transit to the 2nd generation cellulosic ethanol. Based on the overview of cellulosic ethanol industrialization from domestic and abroad in recent years, the main engineering application problems encountered in pretreatment, enzymes and enzymatic hydrolysis, pentose/hexose co-fermentation strains and processes, equipment were discussed from chemical engineering and biotechnology perspective. The development direction of cellulosic ethanol technology in China was addressed.

  8. Cellulosic ethanol is ready to go

    Energy Technology Data Exchange (ETDEWEB)

    Burke, M. [SunOpta BioProcess Group, Brampton, ON (Canada)

    2006-07-01

    A corporate overview of the SunOpta organization was presented. The organization includes three divisions, notably organic food, industrial minerals, and a bioprocess group. It is a Canadian organization that has experienced over 60 per cent growth per year since 1999. The presentation provided a history of the bioprocess group from 1973 to 2003. The presentation also illustrated the biomass process from wood, straw or corn stover to cellulosic ethanol and acetone and butanol. Several images were presented. The production of xylitol from oat hulls and birch and from ryegrass straw to linerboard was also illustrated. Last, the presentation illustrated the biomass production of cellulose, hemicellulose and lignin extraction as well as the ammonia pretreatment of cellulosics. The presentation also listed several current and future developments such as an expansion plan and implementation of cellulosic ethanol. Economic success was defined as requiring proximity to market; high percentage concentration to distillation; and co-located within existing infrastructure. figs.

  9. The Role of Cellulosic Ethanol in Transportation

    Energy Technology Data Exchange (ETDEWEB)

    Robert M. Neilson, Jr.

    2007-10-01

    Petroleum provides essentially all of the energy used today in the transportation sector. To reduce this dependence on fossil energy, other fuels are beginning to be used, notably ethanol and biodiesel. Almost all fuel ethanol is produced by the conversion of corn grain to starch with subsequent fermentation to ethanol. In 2006, almost 5 billion gallons of fuel ethanol were produced, which used 17% of domestic corn production. The DOE has a goal to displace 30% of motor gasoline demand or 60 billion gallons per year by 2030. To achieve this goal, production of ethanol from lignocellulosic sources (e.g., agricultural residues, forest residues, and dedicated energy crops) is needed. This paper will describe the production of cellulosic ethanol as well as the issues and benefits associated with its production.

  10. Biochemical Disincentives to Fertilizing Cellulosic Ethanol Crops

    Science.gov (United States)

    Gallagher, M. E.; Hockaday, W. C.; Snapp, S.; McSwiney, C.; Baldock, J.

    2010-12-01

    Corn grain biofuel crops produce the highest yields when the cropping ecosystem is not nitrogen (N)-limited, achieved by application of fertilizer. There are environmental consequences for excessive fertilizer application to crops, including greenhouse gas emissions, hypoxic “dead zones,” and health problems from N runoff into groundwater. The increase in corn acreage in response to demand for alternative fuels (i.e. ethanol) could exacerbate these problems, and divert food supplies to fuel production. A potential substitute for grain ethanol that could reduce some of these impacts is cellulosic ethanol. Cellulosic ethanol feedstocks include grasses (switchgrass), hardwoods, and crop residues (e.g. corn stover, wheat straw). It has been assumed that these feedstocks will require similar N fertilization rates to grain biofuel crops to maximize yields, but carbohydrate yield versus N application has not previously been monitored. We report the biochemical stocks (carbohydrate, protein, and lignin in Mg ha-1) of a corn ecosystem grown under varying N levels. We measured biochemical yield in Mg ha-1 within the grain, leaf and stem, and reproductive parts of corn plants grown at seven N fertilization rates (0-202 kg N ha-1), to evaluate the quantity and quality of these feedstocks across a N fertilization gradient. The N fertilization rate study was performed at the Kellogg Biological Station-Long Term Ecological Research Site (KBS-LTER) in Michigan. Biochemical stocks were measured using 13C nuclear magnetic resonance spectroscopy (NMR), combined with a molecular mixing model (Baldock et al. 2004). Carbohydrate and lignin are the main biochemicals of interest in ethanol production since carbohydrate is the ethanol feedstock, and lignin hinders the carbohydrate to ethanol conversion process. We show that corn residue carbohydrate yields respond only weakly to N fertilization compared to grain. Grain carbohydrate yields plateau in response to fertilization at

  11. Experimental study on the liquefaction of cellulose in supercritical ethanol

    Science.gov (United States)

    Peng, Jinxing; Liu, Xinyuan; Bao, Zhenbo

    2018-03-01

    Cellulose is the major composition of solid waste for producing biofuel; cellulose liquefaction is helpful for realizing biomass supercritical liquefaction process. This paper is taking supercritical ethanol as the medium, liquefied cellulose with the intermittence installation of high press cauldron. Experiments have studied technical condition and the technology parameter of cellulose liquefaction in supercritical ethanol, and the pyrolysis mechanism was analysed based on the pyrolysis product. Results show that cellulose can be liquefied, can get good effect through appropriate technology condition. Under not catalyst, highest liquefaction rate of cellulose can reach 73.5%. The composition of the pyrolysis product was determined by GC-MS.

  12. Cellulosic ethanol. Potential, technology and development status

    Energy Technology Data Exchange (ETDEWEB)

    Rarbach, M. [Sued-Chemie AG, Muenchen (Germany)

    2012-07-01

    In times of rising oil prices and a growing energy demand, sustainable alternative energy sources are needed. Cellulosic ethanol is a sustainable biofuel, made from lignocellulosic feedstock such as agricultural residues (corn stover, cereal straw, bagasse) or dedicated energy crops. Its production is almost carbon neutral, doesn't compete with food or feed production and induces no land use changes. It constitutes a new energy source using an already existing renewable feedstock without needing any further production capacity and can thus play a major role on the way to more sustainability in transport and the chemical industry and reducing the dependence on the import of fossil resources. The potential for cellulosic ethanol is huge: In the US, the annual production of agricultural residues (cereal straw and corn stover) reached almost 384 million tons in 2009 and Brazil alone produced more than 670 million tons of sugar cane in 2009 yielding more than 100 million tons of bagasse (dry basis). And alone in the European Union, almost 300 million tons of crop straw are produced annually. The last years have seen success in the development and deployment in the field of cellulosic ethanol production. The main challenge thereby remains to demonstrate that the technology is economically feasible for the up-scaling to industrial scale. Clariant has developed the sunliquid {sup registered} process, a proprietary cellulosic ethanol technology that reaches highest greenhouse gas (GHG) emission savings while cutting production costs to a minimum. The sunliquid {sup registered} process for cellulosic ethanol matches the ambitious targets for economically and ecologically sustainable production and greenhouse gas reduction. It was developed using an integrated design concept. Highly optimized, feedstock and process specific biocatalysts and microorganisms ensure a highly efficient process with improved yields and feedstock-driven production costs. Integrated, on

  13. Evaluation of ethanol productivity from cellulose by Clostridium thermocellum

    Energy Technology Data Exchange (ETDEWEB)

    Kurose, N; Yagyu, J; Miyazaki, T; Uchida, M; Hanai, S; Obayashi, A

    1986-01-01

    Clostridium thermocellum, a thermophilic anaerobe, directly converts cellulose to EtOH. To estimate its EtOH production from cellulose, we used a new method based on material balance by which the efficiencies of the enzymes that convert cellulose to ethanol were calculated. Using this method, the maximum efficiency of ethanol production of two strains of C. thermocellum was estimated to be 0.05, with 0.67 as the theoretical maximum. 3 references.

  14. Availability of crop cellulosics for ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, R.D.

    1982-10-01

    Past estimates of cellulosic resources available from Canadian agriculture totalled over 23 million tonnes of cereal grain straw and corn stover residues surplus to soil and animal requirements. A new much reduced estimate, based on four detailed regional studies that also include previously unassessed resources such as chaff, oilseed hulls, and food processing wastes, is suggested. Eleven million tonnes are currently available from all residue sources for energy conversion by different processes. Only five million tonnes are identified as potentially usable in ethanol production plants were they to be constructed. Additional resource opportunities may become available in future from currently underutilized land, especially saline soils, novel processing techniques of conventional grains and forages, innovative cropping systems that may increase the yield of agricultural biomass, and new food/feed/fuel (i.e. multi-purpose) crops such as kochia, milkweed, and Jerusalem artichoke. 27 refs., 1 fig., 1 tab.

  15. Conversion of bagasse cellulose into ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Cuzens, J.E.

    1997-11-19

    The study conducted by Arkenol was designed to test the conversion of feedstocks such as sugar cane bagasse, sorghum, napier grass and rice straw into fermentable sugars, and then ferment these sugars using natural yeasts and genetically engineered Zymomonis mobilis bacteria (ZM). The study did convert various cellulosic feedstocks into fermentable sugars utilizing the patented Arkenol Concentrated Acid Hydrolysis Process and equipment at the Arkenol Technology Center in Orange, California. The sugars produced using this process were in the concentration range of 12--15%, much higher than the sugar concentrations the genetically engineered ZM bacteria had been developed for. As a result, while the ZM bacteria fermented the produced sugars without initial inhibition, the completion of high sugar concentration fermentations was slower and at lower yield than predicted by the National Renewable Energy Laboratory (NREL). Natural yeasts performed as expected by Arkenol, similar to the results obtained over the last four years of testing. Overall, at sugar concentrations in the 10--13% range, yeast produced 850090% theoretical ethanol yields and ZM bacteria produced 82--87% theoretical yields in 96 hour fermentations. Additional commercialization work revealed the ability to centrifugally separate and recycle the ZM bacteria after fermentation, slight additional benefits from mixed culture ZM bacteria fermentations, and successful utilization of defined media for ZM bacteria fermentation nutrients in lieu of natural media.

  16. Grain and cellulosic ethanol: History, economics, and energy policy

    International Nuclear Information System (INIS)

    Solomon, Barry D.; Barnes, Justin R.; Halvorsen, Kathleen E.

    2007-01-01

    The United States (US) and Brazil have been the two leading producers of fuel ethanol since the 1970s. National policies have supported the production and use of ethanol from corn and sugarcane. US support in particular has included exemption from federal gasoline excise taxes, whole or partial exemption from road use (sales) taxes in nine states, a federal production tax credit, and a federal blender's credit. In the last decade the subsidization of grain-based ethanol has been increasingly criticized as economically inefficient and of questionable social benefit. In addition, much greater production of ethanol from corn may conflict with food production needs. A promising development is the acceleration of the technical readiness of cellulosic alcohol fuels, which can be produced from the woody parts of trees and plants, perennial grasses, or residues. This technology is now being commercialized and has greater long-term potential than grain ethanol. Cellulosic ethanol is projected to be much more cost-effective, environmentally beneficial, and have a greater energy output to input ratio than grain ethanol. The technology is being developed in North America, Brazil, Japan and Europe. In this paper, we will review the historical evolution of US federal and state energy policy support for and the currently attractive economics of the production and use of ethanol from biomass. The various energy and economic policies will be reviewed and assessed for their potential effects on cellulosic ethanol development relative to gasoline in the US. (author)

  17. Pavlovian conditioning with ethanol: sign-tracking (autoshaping), conditioned incentive, and ethanol self-administration.

    Science.gov (United States)

    Krank, Marvin D

    2003-10-01

    Conditioned incentive theories of addictive behavior propose that cues signaling a drug's reinforcing effects activate a central motivational state. Incentive motivation enhances drug-taking and drug-seeking behavior. We investigated the behavioral response to cues associated with ethanol and their interaction with operant self-administration of ethanol. In two experiments, rats received operant training to press a lever for a sweetened ethanol solution. After operant training, the animals were given Pavlovian pairings of a brief and localized cue light with the sweetened ethanol solution (no lever present). Lever pressing for ethanol was then re-established, and the behavioral effects of the cue light were tested during an ethanol self-administration session. The conditioned responses resulting from pairing cue lights with the opportunity to ingest ethanol had three main effects: (1) induction of operant behavior reinforced by ethanol, (2) stimulation of ethanol-seeking behavior (magazine entries), and (3) signal-directed behavior (i.e., autoshaping, or sign-tracking). Signal-directed behavior interacted with the other two effects in a manner predicted by the location of the cue light. These conditioned responses interact with operant responding for ethanol reinforcement. These findings demonstrate the importance of Pavlovian conditioning effects on ethanol self-administration and are consistent with conditioned incentive theories of addictive behavior.

  18. Breaking into the Cellulosic Ethanol Market: Capacity and Storage Strategies

    OpenAIRE

    Darby, Paul M.; Mark, Tyler B.; Salassi, Michael E.

    2010-01-01

    This paper examines the possibilities of breaking into the cellulosic ethanol market in south Louisiana via strategic feedstock choices and the leveraging of the area’s competitive advantages. A small plant strategy is devised whereby the first-mover problem might be solved, and several scenarios are tested using Net Present Value analysis.

  19. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Hyun Jong; Wi, Seung Gon; Kim, Su Bae; Shin, You Jung; Yi, Ju Hui [Chonnam National University, Bio-Energy Research Institute, Gwangju (Korea, Republic of)

    2010-10-15

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. Research scope includes 1) screening of various microorganisms from decayed biomass in order to search for more efficient lignocellulose degrading microorganism, 2) identification and verification of new cell wall degrading cellulase for application cellulose bioconversion process, and 3) identification and characterization of novel genes involved in cellulose degradation. To find good microorganism candidates for lignocellulose degrading, 75 decayed samples from different areas were assayed in triplicate and analyzed. For cloning new cell wall degrading enzymes, we selected microorganisms because it have very good lignocellulose degradation ability. From that microorganisms, we have apparently cloned a new cellulase genes (10 genes). We are applying the new cloned cellulase genes to characterize in lignocellulsoe degradation that are most important to cellulosic biofuels production

  20. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    International Nuclear Information System (INIS)

    Bae, Hyun Jong; Wi, Seung Gon; Kim, Su Bae; Shin, You Jung; Yi, Ju Hui

    2010-10-01

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. Research scope includes 1) screening of various microorganisms from decayed biomass in order to search for more efficient lignocellulose degrading microorganism, 2) identification and verification of new cell wall degrading cellulase for application cellulose bioconversion process, and 3) identification and characterization of novel genes involved in cellulose degradation. To find good microorganism candidates for lignocellulose degrading, 75 decayed samples from different areas were assayed in triplicate and analyzed. For cloning new cell wall degrading enzymes, we selected microorganisms because it have very good lignocellulose degradation ability. From that microorganisms, we have apparently cloned a new cellulase genes (10 genes). We are applying the new cloned cellulase genes to characterize in lignocellulsoe degradation that are most important to cellulosic biofuels production

  1. Biomass Supply Chain and Conversion Economics of Cellulosic Ethanol

    Science.gov (United States)

    Gonzalez, Ronalds W.

    2011-12-01

    Cellulosic biomass is a potential and competitive source for bioenergy production, reasons for such acclamation include: biomass is one the few energy sources that can actually be utilized to produce several types of energy (motor fuel, electricity, heat) and cellulosic biomass is renewable and relatively found everywhere. Despite these positive advantages, issues regarding cellulosic biomass availability, supply chain, conversion process and economics need a more comprehensive understanding in order to identify the near short term routes in biomass to bioenergy production. Cellulosic biomass accounts for around 35% to 45% of cost share in cellulosic ethanol production, in addition, different feedstock have very different production rate, (dry ton/acre/year), availability across the year, and chemical composition that affect process yield and conversion costs as well. In the other hand, existing and brand new conversion technologies for cellulosic ethanol production offer different advantages, risks and financial returns. Ethanol yield, financial returns, delivered cost and supply chain logistic for combinations of feedstock and conversion technology are investigated in six studies. In the first study, biomass productivity, supply chain and delivered cost of fast growing Eucalyptus is simulated in economic and supply chain models to supply a hypothetic ethanol biorefinery. Finding suggests that Eucalyptus can be a potential hardwood grown specifically for energy. Delivered cost is highly sensitive to biomass productivity, percentage of covered area. Evaluated at different financial expectations, delivered cost can be competitive compared to current forest feedstock supply. In the second study, Eucalyptus biomass conversion into cellulosic ethanol is simulated in the dilute acid pretreatment, analysis of conversion costs, cost share, CAPEX and ethanol yield are examined. In the third study, biomass supply and delivered cost of loblolly pine is simulated in economic

  2. Analysis of ethanol production potential from cellulosic feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Stone, J E

    1982-03-01

    This report provides a comprehensive and scientific overview of results emerging from research on ethanol producton from cellulosic materials and indicates those areas which appear to warrant additional support. Many published economic analyses of production costs are examined, but the emphasis of the report is on research and on its potential for reducing the cost of ethanol production. The author concludes that the uncertainty surrounding the cost of producing ethanol from cellulosic feedstocks via enzymatic hydrolysis will not be resolved until a pilot plant has been built of sufficient size to produce realistic engineering data. He gives five reasons why Canada should build such a pilot plant: Canada's apparent leadership in developing a steam pre-treatment process, the desirability of encouraging developments and building a cadre of experts in biotechnology, the absence of a pilot plant in Canada where the various organisms and biochemical processes involved in ethanol production and by-product utilization can be developed on a reasonably large scale, Canadian expertise in lignin chemistry which might be used to capitalize upon the reactive lignin residue, and research in progress at National Research Council and elsewhere on the conversion of C/sub 5/ sugars to ethanol. 37 refs., 2 figs., 4 tabs.

  3. Adsorption of Saccharomyces cerevisiae onto cellulose and ecteola-cellulose films for ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Lueng, K.L.; Joshi, S.; Yamazaki, H.

    1983-05-01

    Epichlorohydrin-triethanolamine (ECTEOLA)-cellulose films (paper and cloth) have been found to bind Saccharomyces cerevisiae cells which were able to develop metabolically active colonies on the surface of the films. Umodified cellulose films also bound the yeast but to a lesser extent. Film fermenters were constructed by coiling a double layer of the cloth and copper screen and vertically placing the resulting cartridge into a column. These film fermenters were able to convert the sugars (14%) in the hydrolysate of a Jerusalem artichoke tuber into ethanol, with 90% of the theoretical yield after 6 hours of fermentation. The bound yeast produced ethanol at a specific rate of 1.0 g ethanol per g cell per hour. (Refs. 4).

  4. USE OF IONIC LIQUIDS FOR IMPROVEMENT OF CELLULOSIC ETHANOL PRODUCTION

    Directory of Open Access Journals (Sweden)

    Qijun Wang

    2011-02-01

    Full Text Available Cellulosic ethanol production has drawn much attention in recent years. However, there remain significant technical challenges before such production can be considered as economically feasible at an industrial scale. Among them, the efficient conversion of carbohydrates in lignocellulosic biomass into fermentable sugars is one of the most challenging technical difficulties in cellulosic ethanol production. Use of ionic liquids has opened new avenues to solve this problem by two different pathways. One is pretreatment of lignocellulosic biomass using ionic liquids to increase its enzymatic hydrolysis efficiency. The other is to transform the hydrolysis process of lignocellulosic biomass from a heterogeneous reaction system to a homogeneous one by dissolving it into ionic liquids, thus improving its hydrolysis efficiency.

  5. Maximizing cellulosic ethanol potentials by minimizing wastewater generation and energy consumption: Competing with corn ethanol.

    Science.gov (United States)

    Liu, Gang; Bao, Jie

    2017-12-01

    Energy consumption and wastewater generation in cellulosic ethanol production are among the determinant factors on overall cost and technology penetration into fuel ethanol industry. This study analyzed the energy consumption and wastewater generation by the new biorefining process technology, dry acid pretreatment and biodetoxification (DryPB), as well as by the current mainstream technologies. DryPB minimizes the steam consumption to 8.63GJ and wastewater generation to 7.71tons in the core steps of biorefining process for production of one metric ton of ethanol, close to 7.83GJ and 8.33tons in corn ethanol production, respectively. The relatively higher electricity consumption is compensated by large electricity surplus from lignin residue combustion. The minimum ethanol selling price (MESP) by DryPB is below $2/gal and falls into the range of corn ethanol production cost. The work indicates that the technical and economical gap between cellulosic ethanol and corn ethanol has been almost filled up. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. 75 FR 42745 - Production Incentives for Cellulosic Biofuels: Notice of Program Intent

    Science.gov (United States)

    2010-07-22

    ... Cellulosic Biofuels: Notice of Program Intent AGENCY: Office of Energy Efficiency and Renewable Energy...). Through this notice, biofuels producers and other interested parties are invited to submit pre-auction..., ``Production Incentives for Cellulosic Biofuels; Reverse Auction Procedures and Standards,'' (74 FR 52867...

  7. Method for producing ethanol and co-products from cellulosic biomass

    Science.gov (United States)

    Nguyen, Quang A

    2013-10-01

    The present invention generally relates to processes for production of ethanol from cellulosic biomass. The present invention also relates to production of various co-products of preparation of ethanol from cellulosic biomass. The present invention further relates to improvements in one or more aspects of preparation of ethanol from cellulosic biomass including, for example, improved methods for cleaning biomass feedstocks, improved acid impregnation, and improved steam treatment, or "steam explosion."

  8. Implications of Industrial Processing Strategy on Cellulosic Ethanol Production at High Solids Concentrations

    DEFF Research Database (Denmark)

    Cannella, David

    The production of cellulosic ethanol is a biochemical process of not edible biomasses which contain the cellulose. The process involves the use of enzymes to hydrolyze the cellulose in fermentable sugars to finally produce ethanol via fermentative microorganisms (i.e. yeasts). These biomasses...... are the leftover of agricultural productions (straws), not edible crops (giant reed) or wood, thus the ethanol so produced is also called second generation (or 2G ethanol), which differs from the first generation produced from starch (sugar beets mostly). In the industrial production of cellulosic ethanol high...... solids strategy resulted critical for its cost effectiveness: high concentration of initial biomass it will lead to high concentration of the final product (ethanol), thus more convenient to isolate. This thesis investigate the implementation of a high solids loading concept into cellulosic ethanol...

  9. Fair Oaks Dairy Farms Cellulosic Ethanol Technology Review Summary

    Energy Technology Data Exchange (ETDEWEB)

    Andrew Wold; Robert Divers

    2011-06-23

    At Fair Oaks Dairy, dried manure solids (''DMS'') are currently used as a low value compost. United Power was engaged to evaluate the feasibility of processing these DMS into ethanol utilizing commercially available cellulosic biofuels conversion platforms. The Fair Oaks Dairy group is transitioning their traditional ''manure to methane'' mesophilic anaerobic digester platform to an integrated bio-refinery centered upon thermophilic digestion. Presently, the Digested Manure Solids (DMS) are used as a low value soil amendment (compost). United Power evaluated the feasibility of processing DMS into higher value ethanol utilizing commercially available cellulosic biofuels conversion platforms. DMS was analyzed and over 100 potential technology providers were reviewed and evaluated. DMS contains enough carbon to be suitable as a biomass feedstock for conversion into ethanol by gasification technology, or as part of a conversion process that would include combined heat and power. In the first process, 100% of the feedstock is converted into ethanol. In the second process, the feedstock is combusted to provide heat to generate electrical power supporting other processes. Of the 100 technology vendors evaluated, a short list of nine technology providers was developed. From this, two vendors were selected as finalists (one was an enzymatic platform and one was a gasification platform). Their selection was based upon the technical feasibility of their systems, engineering expertise, experience in commercial or pilot scale operations, the ability or willingness to integrate the system into the Fair Oaks Biorefinery, the know-how or experience in producing bio-ethanol, and a clear path to commercial development.

  10. An energy analysis of ethanol from cellulosic feedstock. Corn stover

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Lin; Van der Voet, Ester; Huppes, Gjalt [Institute of Environmental Sciences (CML), Leiden University, P.O. Box 9518, 2300 RA, Leiden (Netherlands)

    2009-10-15

    The shift from fossil resources to renewables for energy and materials production has been the driving force for research on energy analysis and environmental impact assessment of bio-based production. This study presents a detailed energy analysis of corn stover based ethanol production using advanced cellulosic technologies. The method used differs from that in LCA and from major studies on the subject as published in Science in two respects. First, it accounts for all the co-products together and so mainly avoids the allocation problems which plague all LCA studies explicitly and other studies implicitly. Second, the system boundaries only involve the content of the energy products used in the system but not the production processes of these energy products, like refining and electricity production. We normalized the six Science studies to this unified method. The resulting values of the total energy product use in both agricultural production and biomass conversion to ethanol are lower than these literature values. LCA-type of values including energy conversion would systematically be higher, in our case study around 45%. The net energy value of cellulosic ethanol production is substantially higher than the ones of the corn-based technologies, and it is similar to incineration and gasification for electricity production. The detailed analysis of energy inputs indicates opportunities to optimize the system. This form of energy analysis helps establishing models for the analysis of more complex systems such as biorefineries. (author)

  11. Enhancing ethanol production from cellulosic sugars using Scheffersomyces (Pichia) stipitis.

    Science.gov (United States)

    Okonkwo, C C; Azam, M M; Ezeji, T C; Qureshi, N

    2016-07-01

    Studies were performed on the effect of CaCO3 and CaCl2 supplementation to fermentation medium for ethanol production from xylose, glucose, or their mixtures using Scheffersomyces (Pichia) stipitis. Both of these chemicals were found to improve maximum ethanol concentration and ethanol productivity. Use of xylose alone resulted in the production of 20.68 ± 0.44 g L(-1) ethanol with a productivity of 0.17 ± 0.00 g L(-1) h(-1), while xylose plus 3 g L(-1) CaCO3 resulted in the production of 24.68 ± 0.75 g L(-1) ethanol with a productivity of 0.21 ± 0.01 g L(-1) h(-1). Use of xylose plus glucose in combination with 3 g L(-1) CaCO3 resulted in the production of 47.37 ± 0.55 g L(-1) ethanol (aerobic culture), thus resulting in an ethanol productivity of 0.39 ± 0.00 g L(-1) h(-1). These values are 229 % of that achieved in xylose medium. Supplementation of xylose and glucose medium with 0.40 g L(-1) CaCl2 resulted in the production of 44.84 ± 0.28 g L(-1) ethanol with a productivity of 0.37 ± 0.02 g L(-1) h(-1). Use of glucose plus 3 g L(-1) CaCO3 resulted in the production of 57.39 ± 1.41 g L(-1) ethanol under micro-aerophilic conditions. These results indicate that supplementation of cellulosic sugars in the fermentation medium with CaCO3 and CaCl2 would improve economics of ethanol production from agricultural residues.

  12. Value Chain Structures that Define European Cellulosic Ethanol Production

    DEFF Research Database (Denmark)

    Gregg, Jay Sterling; Bolwig, Simon; Hansen, Teis

    2017-01-01

    production plants across Europe from a global value chain (GVC) perspective. We find that most CE production plants in the EU focus largely on intellectual property and are therefore only at the pilot or demonstration scale. Crescentino, the largest CE production facility in Europe, is also more interested...... petroleum markets and higher financial risks. We argue that, to increase CE production, policies should consider value chains, promote the wider bio-economy of products and focus on economies of scope. Whereas the EU and its member states have ethanol quotas and blending targets, a more effective policy......Production of cellulosic ethanol (CE) has not yet reached the scale envisaged by the literature and industry. This study explores CE production in Europe to improve understanding of the motivations and barriers associated with this situation. To do this, we conduct a case study-based analysis of CE...

  13. The Potential of Cellulosic Ethanol Production from Grasses in Thailand

    Directory of Open Access Journals (Sweden)

    Jinaporn Wongwatanapaiboon

    2012-01-01

    Full Text Available The grasses in Thailand were analyzed for the potentiality as the alternative energy crops for cellulosic ethanol production by biological process. The average percentage composition of cellulose, hemicellulose, and lignin in the samples of 18 types of grasses from various provinces was determined as 31.85–38.51, 31.13–42.61, and 3.10–5.64, respectively. The samples were initially pretreated with alkaline peroxide followed by enzymatic hydrolysis to investigate the enzymatic saccharification. The total reducing sugars in most grasses ranging from 500–600 mg/g grasses (70–80% yield were obtained. Subsequently, 11 types of grasses were selected as feedstocks for the ethanol production by simultaneous saccharification and cofermentation (SSCF. The enzymes, cellulase and xylanase, were utilized for hydrolysis and the yeasts, Saccharomyces cerevisiae and Pichia stipitis, were applied for cofermentation at 35°C for 7 days. From the results, the highest yield of ethanol, 1.14 g/L or 0.14 g/g substrate equivalent to 32.72% of the theoretical values was obtained from Sri Lanka ecotype vetiver grass. When the yields of dry matter were included in the calculations, Sri Lanka ecotype vetiver grass gave the yield of ethanol at 1,091.84 L/ha/year, whereas the leaves of dwarf napier grass showed the maximum yield of 2,720.55 L/ha/year (0.98 g/L or 0.12 g/g substrate equivalent to 30.60% of the theoretical values.

  14. Integrated production of nano-fibrillated cellulose and cellulosic biofuel (ethanol) by enzymatic fractionation of wood fibers

    Science.gov (United States)

    Junyong Zhu; Ronald Sabo; Xiaolin Luo

    2011-01-01

    This study demonstrates the feasibility of integrating the production of nano-fibrillated cellulose (NFC), a potentially highly valuable biomaterial, with sugar/biofuel (ethanol) from wood fibers. Commercial cellulase enzymes were used to fractionate the less recalcitrant amorphous cellulose from a bleached Kraft eucalyptus pulp, resulting in a highly crystalline and...

  15. Assessing Resource Intensity and Renewability of Cellulosic Ethanol Technologies using Eco-LCA

    Science.gov (United States)

    Recognizing the contributions of natural resources and the lack of their comprehensive accounting in life cycle assessment (LCA) of cellulosic ethanol, an in-depth analysis of the contribution of natural resources in the life cycle of cellulosic ethanol derived from five differen...

  16. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    International Nuclear Information System (INIS)

    Bae, Hyeun Jong; Wi, Seung Gon; Lee, Yoon Gyo; Kim, Ho Myung; Kim, Su Bae

    2011-10-01

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. The 2nd year Research scope includes: 1) Optimization of pre-treatment conditions for enzymatic hydrolysis of lignocellulosic biomass and 2) Demonstration of enzymatic hydrolysis by recombinant enzymes. To optimize the pretreatment, we applied two processes: a wet process (wet milling + popping), and dry process (popping + dry milling). Out of these, the wet process presented the best glucose yield with a 93.1% conversion, while the dry process yielded 69.6%, and the unpretreated process yielded <20%. The recombinant cellulolytic enzymes showed very high specific activity, about 80-1000 times on CMC and 13-70 times on filter paper at pH 3.5 and 55 .deg. C

  17. Value Chain Structures that Define European Cellulosic Ethanol Production

    Directory of Open Access Journals (Sweden)

    Jay Sterling Gregg

    2017-01-01

    Full Text Available Production of cellulosic ethanol (CE has not yet reached the scale envisaged by the literature and industry. This study explores CE production in Europe to improve understanding of the motivations and barriers associated with this situation. To do this, we conduct a case study-based analysis of CE production plants across Europe from a global value chain (GVC perspective. We find that most CE production plants in the EU focus largely on intellectual property and are therefore only at the pilot or demonstration scale. Crescentino, the largest CE production facility in Europe, is also more interested in technology licensing than producing ethanol. Demonstration-scale plants tend to have a larger variety of feedstocks, whereas forestry-based plants have more diversity of outputs. As scale increases, the diversity of feedstocks and outputs diminishes, and firms struggle with feedstock provisioning, global petroleum markets and higher financial risks. We argue that, to increase CE production, policies should consider value chains, promote the wider bio-economy of products and focus on economies of scope. Whereas the EU and its member states have ethanol quotas and blending targets, a more effective policy would be to seek to reduce the risks involved in financing capital projects, secure feedstock provisioning and support a diversity of end products.

  18. Cellulosic ethanol production from agricultural residues in Nigeria

    International Nuclear Information System (INIS)

    Iye, Edward; Bilsborrow, Paul

    2013-01-01

    Nigeria′s Biofuels Policy introduced in 2007 mandates a 10% blend (E10) of bioethanol with gasoline. This study investigates the potential for the development of a cellulosic ethanol industry based on the availability of agricultural residues and models the number of commercial processing facilities that could be sited in the six Geo-political zones. The potential for cellulosic ethanol production from agricultural residues in Nigeria is 7556 km 3 per annum exceeding the mandate of 10% renewable fuel required and providing the potential for 12 large- and 11 medium-scale processing facilities based on the use of a single feedstock. Cassava and yam peelings provided in excess of 80% of the process residues available with enough feedstock to supply 10 large-scale facilities with a fairly even distribution across the zones. Sorghum straw, millet straw and maize stalks represented 75% of the potential resource available from field residues with the potential to supply 2 large- and 7 medium-scale processing facilities, all of which would be located in the north of the country. When a multi-feedstock approach is used, this provides the potential for either 29 large- or 58 medium-scale facilities based on outputs of 250 and 125 km 3 per annum respectively. - Highlights: • Nigeria′s Biofuels Policy mandates a 10% blend of bioethanol with gasoline. • Total bioethanol production from agricultural residues was 7556 km 3 per annum. • Process residues offer the greatest potential accounting for 62% of production. • Nigeria has the potential for 12 large- and 11 medium scale commercial. • The use of mixed feedstocks significantly increases the potential for production

  19. Direct conversion of straw to ethanol by Fusarium oxysporum: effect of cellulose crystallinity

    Energy Technology Data Exchange (ETDEWEB)

    Christakopoulos, P.; Koullas, D.P.; Kekos, D.; Koukios, E.G.; Macris, B.J. (Ethnikon Metsovion Polytechneion, Athens (Greece))

    1991-03-01

    Wheat straw was successfully fermented to ethanol by Fusarium oxysporum F3 in a one-step process. Cellulose crystallinity was found to be a major factor in the bioconversion process. Ethanol yields increased linearly with decreasing crystallinity index. Approximately 80% of straw carbohydrates were converted directly to ethanol with a yield of 0.28 g ethanol/g{sup -1} of straw when the crystallinity index was reduced to 23.6%. (author).

  20. Process and utility water requirements for cellulosic ethanol production processes via fermentation pathway

    Science.gov (United States)

    The increasing need of additional water resources for energy production is a growing concern for future economic development. In technology development for ethanol production from cellulosic feedstocks, a detailed assessment of the quantity and quality of water required, and the ...

  1. Process development studies on the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.; Blanch, H.W.

    1978-12-01

    Progress is reported in the following areas: raw materials and process evaluation, enzyme fermentation studies, ethanol fermentation studies, hydrolysis reactor development, and utilization of hemi-cellulose sugars. (MHR)

  2. Modelling ethanol production from cellulose: separate hydrolysis and fermentation versus simultaneous saccharification and fermentation

    NARCIS (Netherlands)

    Drissen, R.E.T.; Maas, R.H.W.; Tramper, J.; Beeftink, H.H.

    2009-01-01

    In ethanol production from cellulose, enzymatic hydrolysis, and fermentative conversion may be performed sequentially (separate hydrolysis and fermentation, SHF) or in a single reaction vessel (simultaneous saccharification and fermentation, SSF). Opting for either is essentially a trade-off between

  3. Long-run effects of falling cellulosic ethanol production costs on the US agricultural economy

    International Nuclear Information System (INIS)

    Campiche, Jody L; Bryant, Henry L; Richardson, James W

    2010-01-01

    Renewable energy production has been expanding at a rapid pace. New advances in cellulosic ethanol technologies have the potential to displace the use of petroleum as a transportation fuel, and could have significant effects on both the agricultural economy and the environment. In this letter, the effects of falling cellulosic ethanol production costs on the mix of ethanol feedstocks employed and on the US agricultural economy are examined. Results indicate that, as expected, cellulosic ethanol production increases by a substantial amount as conversion technology improves. Corn production increases initially following the introduction of cellulosic technology, because producers enjoy new revenue from sales of corn stover. After cellulosic ethanol production becomes substantially cheaper, however, acres are shifted from corn production to all other agricultural commodities. Essentially, this new technology could facilitate the exploitation of a previously under-employed resource (corn stover), resulting in an improvement in overall welfare. In the most optimistic scenario considered, 68% of US ethanol is derived from cellulosic sources, coarse grain production is reduced by about 2%, and the prices of all food commodities are reduced modestly.

  4. High-resolution techno-ecological modelling of a bioenergy landscape to identify climate mitigation opportunities in cellulosic ethanol production

    Science.gov (United States)

    Field, John L.; Evans, Samuel G.; Marx, Ernie; Easter, Mark; Adler, Paul R.; Dinh, Thai; Willson, Bryan; Paustian, Keith

    2018-03-01

    Although dedicated energy crops will probably be an important feedstock for future cellulosic bioenergy production, it is unknown how they can best be integrated into existing agricultural systems. Here we use the DayCent ecosystem model to simulate various scenarios for growing switchgrass in the heterogeneous landscape that surrounds a commercial-scale cellulosic ethanol biorefinery in southwestern Kansas, and quantify the associated fuel production costs and lifecycle greenhouse gas (GHG) emissions. We show that the GHG footprint of ethanol production can be reduced by up to 22 g of CO2 equivalent per megajoule (CO2e MJ-1) through careful optimization of the soils cultivated and corresponding fertilizer application rates (the US Renewable Fuel Standard requires a 56 gCO2e MJ-1 lifecycle emissions reduction for `cellulosic' biofuels compared with conventional gasoline). This improved climate performance is realizable at modest additional costs, less than the current value of low-carbon fuel incentives. We also demonstrate that existing subsidized switchgrass plantings within this landscape probably achieve suboptimal GHG mitigation, as would landscape designs that strictly minimize the biomass collection radius or target certain marginal lands.

  5. Characteristics of the products of hydrothermal liquefaction combined with cellulosic bio-ethanol process

    International Nuclear Information System (INIS)

    Li, Rundong; Xie, Yinghui; Yang, Tianhua; Li, Bingshuo; Zhang, Yang; Kai, Xingping

    2016-01-01

    The integration utilization of fermentation residues from cellulosic bio-ethanol has attracted a great deal of attention to balance the total cost of bio-ethanol production while simultaneously dealing with bio-ethanol wastewater. A process of hydrothermal liquefaction (HTL) of intact materials from cellulosic bio-ethanol in a batch reactor was proposed. The effects of the reaction temperature and time on the liquefaction characteristics were examined. The optimum condition for liquefaction fermentation residues was 370 °C (21.25 MPa) and 30 min with a bio-oil yield of 40.79 wt%. GC-MS results indicated that the major chemical species in the bio-oil were phenols, ketones, long-chain hydrocarbons and fatty acids. Supercritical conditions (375 °C, 23.50 MPa) was favored for the low-molecular-weight species formation compared to subcritical conditions (370 °C, 21.25 MPa), as some long-chain species decreased. This work thus can provide a novel idea for bio-oil production from HTL of cellulosic bio-ethanol fermentation residues. - Highlights: • Bio-oil production via HTL combined with cellulosic bio-ethanol process was proposed. • Optimum condition for HTL of materials from cellulosic bio-ethanol was 370 °C and 30 min. • Bio-oil contained higher content of hydrocarbons and lower contents of organic acids.

  6. Overview of technical barriers and implementation of cellulosic ethanol in the U.S

    International Nuclear Information System (INIS)

    Kim, Tae Hoon; Kim, Tae Hyun

    2014-01-01

    There is mounting concern about the buildup of carbon dioxide (CO 2 ) and other so-called greenhouse gases in the atmosphere. In general, bioethanol production requires minimal fossil fuel input in the conversion step, and ethanol is considered a promising alternative fuel to petroleum-derived products. It is anticipated that ethanol production with second-generation biomass, i.e. lignocellulosic materials, will be possible on a large scale in the near future. Latest efforts have been focused on overcoming technical challenges in bioconversion, particularly pretreatment, and finding the solutions required to implement biorefinery on a large scale. This paper introduces and reviews the current status of research, and of the ethanol industry in the U.S. In addition, other important concepts in biofuels, cellulosic ethanol, and biorefinery in general are reviewed, and the key technical issues in bioconversion of cellulosic ethanol, such as pretreatment and factors affecting bioconversion of biomass are also discussed. - Highlights: • The current status of research, and of the ethanol industry in the U.S. • Important concepts in biofuels, cellulosic ethanol, and biorefinery. • The key technical issues in bioconversion of cellulosic ethanol. • Pretreatment and factors affecting bioconversion of biomass

  7. Nanofibrillated Cellulose (NFC: A High-Value Co-Product that Improves the Economics of Cellulosic Ethanol Production

    Directory of Open Access Journals (Sweden)

    Qiong Song

    2014-02-01

    Full Text Available Cellulosic ethanol is a sustainable alternative to petroleum as a transportation fuel, which could be made biologically from agricultural and forestry residues, municipal waste, or herbaceous and woody crops. Instead of putting efforts on steps overcoming the natural resistance of plants to biological breakdown, our study proposes a unique pathway to improve the outcome of the process by co-producing high-value nanofibrillated cellulose (NFC, offering a new economic leverage for cellulosic ethanol to compete with fossil fuels in the near future. In this study, glucose has been produced by commercial enzymes while the residual solids are converted into NFC via sonification. Here, we report the morphology of fibers changed through the process and yield of glucose in the enzymatic hydrolysis step.

  8. Ethanol production from cellulose, lactose and xylose using yeasts and enzymes. Gewinnung von Ethanol aus Cellulose, Lactose, und Xylose mit Hilfe von Hefen und Enzymen

    Energy Technology Data Exchange (ETDEWEB)

    Schwank, U

    1986-07-03

    Experiments with mixtures of whey and corn showed that more than 85% of the lactose was degraded into ethanol. The applicability of cellulose was investigated by means of potatoes. Cellulase is inhibited by glucose, which is a fermentation intermediate, as well as by the end product ethanol. A cellulase inhibitor in potatoes was detected and stabilized; this inhibitor could be degraded into neutral components by a suitable enzyme. Saccharification and fermentation experiments showed that the cellulose fraction of potatoes can be reduced efficiently. The effects of non-enzymatic pretreatment on enzymatic degradation of cellulose, combined with fermentation of the degradation products, are illustrated by the example of cellulose treated with acid and alkaline substances. A continuous fermentation system was developed from which the ethanol is withdrawn in vapour form. The system made better use of the cellulase activity and increased the efficiency of a xylose-fermenting yeast. The new method is compared with batch experiments in order to assess its efficiency. The advantages of the continuous process are proved for two yeasts of the species Pachysolu and Pichia. Specific fermentation rates up to 0.08 g/(g x h) and fermentation yields up to 0.42 g ethanol/g xylose were achieved with Pichia stipitis.

  9. Physical Energy Accounting in California: A Case Study of Cellulosic Ethanol Production

    Energy Technology Data Exchange (ETDEWEB)

    Coughlin, Katie; Fridley, David

    2008-07-17

    California's target for greenhouse gas reduction in part relies on the development of viable low-carbon fuel alternatives to gasoline. It is often assumed that cellulosic ethanol--ethanol made from the structural parts of a plant and not from the food parts--will be one of these alternatives. This study examines the physical viability of a switchgrass-based cellulosic ethanol industry in California from the point of view of the physical requirements of land, water, energy and other material use. Starting from a scenario in which existing irrigated pastureland and fiber-crop land is converted to switchgrass production, the analysis determines the total acreage and water supply available and the resulting total biofuel feedstock output under different assumed yields. The number and location of cellulosic ethanol biorefineries that can be supported is also determined, assuming that the distance from field to biorefinery would be minimized. The biorefinery energy input requirement, available energy from the fraction of biomass not converted to ethanol, and energy output is calculated at various levels of ethanol yields, making different assumptions about process efficiencies. The analysis shows that there is insufficient biomass (after cellulose separation and fermentation into ethanol) to provide all the process energy needed to run the biorefinery; hence, the purchase of external energy such as natural gas is required to produce ethanol from switchgrass. The higher the yield of ethanol, the more external energy is needed, so that the net gains due to improved process efficiency may not be positive. On 2.7 million acres of land planted in switchgrass in this scenario, the switchgrass outputproduces enough ethanol to substitute for only 1.2 to 4.0percent of California's gasoline consumption in 2007.

  10. The operable modeling of simultaneous saccharification and fermentation of ethanol production from cellulose.

    Science.gov (United States)

    Shen, Jiacheng; Agblevor, Foster A

    2010-03-01

    An operable batch model of simultaneous saccharification and fermentation (SSF) for ethanol production from cellulose has been developed. The model includes four ordinary differential equations that describe the changes of cellobiose, glucose, yeast, and ethanol concentrations with respect to time. These equations were used to simulate the experimental data of the four main components in the SSF process of ethanol production from microcrystalline cellulose (Avicel PH101). The model parameters at 95% confidence intervals were determined by a MATLAB program based on the batch experimental data of the SSF. Both experimental data and model simulations showed that the cell growth was the rate-controlling step at the initial period in a series of reactions of cellulose to ethanol, and later, the conversion of cellulose to cellobiose controlled the process. The batch model was extended to the continuous and fed-batch operating models. For the continuous operation in the SSF, the ethanol productivities increased with increasing dilution rate, until a maximum value was attained, and rapidly decreased as the dilution rate approached the washout point. The model also predicted a relatively high ethanol mass for the fed-batch operation than the batch operation.

  11. Process Design of Wastewater Treatment for the NREL Cellulosic Ethanol Model

    Energy Technology Data Exchange (ETDEWEB)

    Steinwinder, T.; Gill, E.; Gerhardt, M.

    2011-09-01

    This report describes a preliminary process design for treating the wastewater from NREL's cellulosic ethanol production process to quality levels required for recycle. In this report Brown and Caldwell report on three main tasks: 1) characterization of the effluent from NREL's ammonia-conditioned hydrolyzate fermentation process; 2) development of the wastewater treatment process design; and 3) development of a capital and operational cost estimate for the treatment concept option. This wastewater treatment design was incorporated into NREL's cellulosic ethanol process design update published in May 2011 (NREL/TP-5100-47764).

  12. Ethanol Production from Various Sugars and Cellulosic Biomass by White Rot Fungus Lenzites betulinus.

    Science.gov (United States)

    Im, Kyung Hoan; Nguyen, Trung Kien; Choi, Jaehyuk; Lee, Tae Soo

    2016-03-01

    Lenzites betulinus, known as gilled polypore belongs to Basidiomycota was isolated from fruiting body on broadleaf dead trees. It was found that the mycelia of white rot fungus Lenzites betulinus IUM 5468 produced ethanol from various sugars, including glucose, mannose, galactose, and cellobiose with a yield of 0.38, 0.26, 0.07, and 0.26 g of ethanol per gram of sugar consumed, respectively. This fungus relatively exhibited a good ethanol production from xylose at 0.26 g of ethanol per gram of sugar consumed. However, the ethanol conversion rate of arabinose was relatively low (at 0.07 g of ethanol per gram sugar). L. betulinus was capable of producing ethanol directly from rice straw and corn stalks at 0.22 g and 0.16 g of ethanol per gram of substrates, respectively, when this fungus was cultured in a basal medium containing 20 g/L rice straw or corn stalks. These results indicate that L. betulinus can produce ethanol efficiently from glucose, mannose, and cellobiose and produce ethanol very poorly from galactose and arabinose. Therefore, it is suggested that this fungus can ferment ethanol from various sugars and hydrolyze cellulosic materials to sugars and convert them to ethanol simultaneously.

  13. Influence of the crystalline structure of cellulose on the production of ethanol from lignocellulose biomass

    Science.gov (United States)

    Smuga-Kogut, Małgorzata; Zgórska, Kazimiera; Szymanowska-Powałowska, Daria

    2016-01-01

    In recent years, much attention has been devoted to the possibility of using lignocellulosic biomass for energy. Bioethanol is a promising substitute for conventional fossil fuels and can be produced from straw and wood biomass. Therefore, the aim of this paper was to investigate the effect of 1-ethyl-3-methylimidazolium pretreatment on the structure of cellulose and the acquisition of reducing sugars and bioethanol from cellulosic materials. Material used in the study was rye straw and microcrystalline cellulose subjected to ionic liquid 1-ethyl-3-methylimidazolium pretreatment. The morphology of cellulose fibres in rye straw and microcrystalline cellulose was imaged prior to and after ionic liquid pretreatment. Solutions of ionic liquid-treated and untreated cellulosic materials were subjected to enzymatic hydrolysis in order to obtain reducing sugars, which constituted a substrate for alcoholic fermentation. An influence of the ionic liquid on the cellulose structure, accumulation of reducing sugars in the process of hydrolysis of this material, and an increase in ethanol amount after fermentation was observed. The ionic liquid did not affect cellulolytic enzymes negatively and did not inhibit yeast activity. The amount of reducing sugars and ethyl alcohol was higher in samples purified with 1-ethyl-3-methy-limidazolium acetate. A change in the supramolecular structure of cellulose induced by the ionic liquid was also observed.

  14. An evaluation of dilute acid and ammonia fiber explosion pretreatment for cellulosic ethanol production.

    Science.gov (United States)

    Mathew, Anil Kuruvilla; Parameshwaran, Binod; Sukumaran, Rajeev Kumar; Pandey, Ashok

    2016-01-01

    The challenge associated with cellulosic ethanol production is maximizing sugar yield at low cost. Current research is being focused to develop a pretreatment method to overcome biomass recalcitrance in an efficient way. This review is focused on two major pretreatments: dilute acid (DA) and ammonia fiber explosion (AFEX) pretreatment of corn stover and how these pretreatment cause morphological and chemical changes to corn stover in order to overcome the biomass recalcitrance. This review highlights the key differences of these two pretreatments based on compositional analysis, cellulose and its crystallinity, morphological changes, structural changes to lignin, enzymatic reactivity and enzyme adsorption onto pretreated solids and finally cellulosic ethanol production from the hydrolysate of DA and AFEX treated corn stover. Each stage of the process, AFEX pretreated corn stover was superior to DA treated corn stover. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Impact of pretreatment and downstream processing technologies on economics and energy in cellulosic ethanol production

    Directory of Open Access Journals (Sweden)

    Murthy Ganti S

    2011-09-01

    Full Text Available Abstract Background While advantages of biofuel have been widely reported, studies also highlight the challenges in large scale production of biofuel. Cost of ethanol and process energy use in cellulosic ethanol plants are dependent on technologies used for conversion of feedstock. Process modeling can aid in identifying techno-economic bottlenecks in a production process. A comprehensive techno-economic analysis was performed for conversion of cellulosic feedstock to ethanol using some of the common pretreatment technologies: dilute acid, dilute alkali, hot water and steam explosion. Detailed process models incorporating feedstock handling, pretreatment, simultaneous saccharification and co-fermentation, ethanol recovery and downstream processing were developed using SuperPro Designer. Tall Fescue (Festuca arundinacea Schreb was used as a model feedstock. Results Projected ethanol yields were 252.62, 255.80, 255.27 and 230.23 L/dry metric ton biomass for conversion process using dilute acid, dilute alkali, hot water and steam explosion pretreatment technologies respectively. Price of feedstock and cellulose enzymes were assumed as $50/metric ton and 0.517/kg broth (10% protein in broth, 600 FPU/g protein respectively. Capital cost of ethanol plants processing 250,000 metric tons of feedstock/year was $1.92, $1.73, $1.72 and $1.70/L ethanol for process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Ethanol production cost of $0.83, $0.88, $0.81 and $0.85/L ethanol was estimated for production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Water use in the production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment was estimated 5.96, 6.07, 5.84 and 4.36 kg/L ethanol respectively. Conclusions Ethanol price and energy use were highly dependent on process conditions used in the ethanol production plant. Potential for

  16. A whole cell biocatalyst for cellulosic ethanol production from dilute acid-pretreated corn stover hydrolyzates

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Seunghyun; Karim, Muhammad Nazmul [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemical Engineering

    2011-08-15

    In this research, a recombinant whole cell biocatalyst was developed by expressing three cellulases from Clostridium cellulolyticum - endoglucanase (Cel5A), exoglucanase (Cel9E), and {beta}-glucosidase - on the surface of the Escherichia coli LY01. The modified strain is identified as LY01/pRE1H-AEB. The cellulases were displayed on the surface of the cell by fusing with an anchor protein, PgsA. The developed whole cell biocatalyst was used for single-step ethanol fermentation using the phosphoric acid-swollen cellulose (PASC) and the dilute acid-pretreated corn stover. Ethanol production was 3.59 {+-} 0.15 g/L using 10 g/L of PASC, which corresponds to a theoretical yield of 95.4 {+-} 0.15%. Ethanol production was 0.30 {+-} 0.02 g/L when 1 g/L equivalent of glucose in the cellulosic fraction of the dilute sulfuric acid-pretreated corn stover (PCS) was fermented for 84 h. A total of 0.71 {+-} 0.12 g/L ethanol was produced in 48 h when the PCS was fermented in the simultaneous saccharification and co-fermentation mode using the hemicellulosic (1 g/L of total soluble sugar) and as well as the cellulosic (1 g/L of glucose equivalent) parts of PCS. In a control experiment, 0.48 g/L ethanol was obtained from 1 g/L of hemicellulosic PCS. It was concluded that the whole cell biocatalyst could convert both cellulosic and hemicellulosic substrates into ethanol in a single reactor. The developed C. cellulolyticum-E. coli whole cell biocatalyst also overcame the incompatible temperature problem of the frequently reported fungal-yeast systems. (orig.)

  17. Bioconversion of paper sludge with low cellulosic content to ethanol ...

    African Journals Online (AJOL)

    The purpose of the present work was to evaluate the possibility of converting paper sludge into ethanol using xylose-fermenting yeast SHY07-1 in separate hydrolysis and fermentation. In the enzymatic hydrolysis step, sludge on 2% (w/v, expressed in terms of total carbohydrate mass) substrate consistency was incubated ...

  18. The production of cellulosic ethanol using SMR. A prefeasibility study for the Italian scenario

    International Nuclear Information System (INIS)

    Locatelli, Giorgio; Mancini, Mauro

    2011-01-01

    Small Medium Reactors (SMR) can play an important role in the global nuclear renaissance coupling the production of Electrical Energy (EE) with by-products useful to increase their economic attractiveness and enhance the public acceptability. Light Water Reactors (LWR) have an average thermal efficiency of about 33%-35%, therefore two third of the thermal energy produced by the nuclear reaction is usually wasted. Nowadays there are industries able to use this thermal energy in an efficient way. Among the other the production of cellulosic ethanol seems one of the most attractive for the coupling with a nuclear power plant. This industry can exploit two by-products of a nuclear reactor: the wide area around the plant (the so called Emergency Planning Zone - EPZ) and the residual thermal energy post turbines. Cellulosic ethanol is a bio-fuel produced from non-edible parts of plants or wood. It is produced from lignocellulose the material composing much of the mass of plants. Production of ethanol (that can be used as a fuel) from lignocellulose can avoid the usage of food grain or precious vegetables usable for the human nutrition, but requires an enormous amount of heat in the production process. A SMR can be the ideal source of this thermal energy. The paper presents a prefeasibility study with the economic and strategic assessment of coupling an SMR and a cellulosic ethanol plant in the north of Italy. After an introduction on the ethanol production the papers describe the market of this product and the production process. Then it provides the cost estimation of coupling the SMR with the production plant. The results point out as this combination can be very attractive to enhance the production of ethanol since is really cost competitive and does not produce any green house gases (GHG). (author)

  19. The feasibility of producing adequate feedstock for year–round cellulosic ethanol production in an intensive agricultural fuelshed

    Science.gov (United States)

    Uden, Daniel R.; Mitchell, Rob B.; Allen, Craig R.; Guan, Qingfeng; McCoy, Tim D.

    2013-01-01

    To date, cellulosic ethanol production has not been commercialized in the United States. However, government mandates aimed at increasing second-generation biofuel production could spur exploratory development in the cellulosic ethanol industry. We conducted an in-depth analysis of the fuelshed surrounding a starch-based ethanol plant near York, Nebraska that has the potential for cellulosic ethanol production. To assess the feasibility of supplying adequate biomass for year-round cellulosic ethanol production from residual maize (Zea mays) stover and bioenergy switchgrass (Panicum virgatum) within a 40-km road network service area of the existing ethanol plant, we identified ∼14,000 ha of marginally productive cropland within the service area suitable for conversion from annual rowcrops to switchgrass and ∼132,000 ha of maize-enrolled cropland from which maize stover could be collected. Annual maize stover and switchgrass biomass supplies within the 40-km service area could range between 429,000 and 752,000 metric tons (mT). Approximately 140–250 million liters (l) of cellulosic ethanol could be produced, rivaling the current 208 million l annual starch-based ethanol production capacity of the plant. We conclude that sufficient quantities of biomass could be produced from maize stover and switchgrass near the plant to support year-round cellulosic ethanol production at current feedstock yields, sustainable removal rates and bioconversion efficiencies. Modifying existing starch-based ethanol plants in intensive agricultural fuelsheds could increase ethanol output, return marginally productive cropland to perennial vegetation, and remove maize stover from productive cropland to meet feedstock demand.

  20. Breaking the Biological Barriers to Cellulosic Ethanol: A Joint Research Agenda

    Energy Technology Data Exchange (ETDEWEB)

    Houghton, John [Dept. of Energy (DOE), Washington DC (United States); Weatherwax, Sharlene [Dept. of Energy (DOE), Washington DC (United States); Ferrell, John [Dept. of Energy (DOE), Washington DC (United States)

    2006-06-07

    The Biomass to Biofuels Workshop, held December 7–9, 2005, was convened by the Department of Energy’s Office of Biological and Environmental Research in the Office of Science; and the Office of the Biomass Program in the Office of Energy Efficiency and Renewable Energy. The purpose was to define barriers and challenges to a rapid expansion of cellulosic-ethanol production and determine ways to speed solutions through concerted application of modern biology tools as part of a joint research agenda. Although the focus was ethanol, the science applies to additional fuels that include biodiesel and other bioproducts or coproducts having critical roles in any deployment scheme.

  1. Direct Conversion of Cellulose into Ethyl Lactate in Supercritical Ethanol-Water Solutions.

    Science.gov (United States)

    Yang, Lisha; Yang, Xiaokun; Tian, Elli; Lin, Hongfei

    2016-01-08

    Biomass-derived ethyl lactate is a green solvent with a growing market as the replacement for petroleum-derived toxic organic solvents. Here we report, for the first time, the production of ethyl lactate directly from cellulose with the mesoporous Zr-SBA-15 silicate catalyst in a supercritical mixture of ethanol and water. The relatively strong Lewis and weak Brønsted acid sites on the catalyst, as well as the surface hydrophobicity, were beneficial to the reaction and led to synergy during consecutive reactions, such as depolymerization, retro-aldol condensation, and esterification. Under the optimum reaction conditions, ∼33 % yield of ethyl lactate was produced from cellulose with the Zr-SBA-15 catalyst at 260 °C in supercritical 95:5 (w/w) ethanol/water. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Improvement of ethanol production from crystalline cellulose via optimizing cellulase ratios in cellulolytic Saccharomyces cerevisiae.

    Science.gov (United States)

    Liu, Zhuo; Inokuma, Kentaro; Ho, Shih-Hsin; den Haan, Riaan; van Zyl, Willem H; Hasunuma, Tomohisa; Kondo, Akihiko

    2017-06-01

    Crystalline cellulose is one of the major contributors to the recalcitrance of lignocellulose to degradation, necessitating high dosages of cellulase to digest, thereby impeding the economic feasibility of cellulosic biofuels. Several recombinant cellulolytic yeast strains have been developed to reduce the cost of enzyme addition, but few of these strains are able to efficiently degrade crystalline cellulose due to their low cellulolytic activities. Here, by combining the cellulase ratio optimization with a novel screening strategy, we successfully improved the cellulolytic activity of a Saccharomyces cerevisiae strain displaying four different synergistic cellulases on the cell surface. The optimized strain exhibited an ethanol yield from Avicel of 57% of the theoretical maximum, and a 60% increase of ethanol titer from rice straw. To our knowledge, this work is the first optimization of the degradation of crystalline cellulose by tuning the cellulase ratio in a cellulase cell-surface display system. This work provides key insights in engineering the cellulase cocktail in a consolidated bioprocessing yeast strain. Biotechnol. Bioeng. 2017;114: 1201-1207. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  3. Integrated energy, environmental and financial analysis of ethanol production from cellulosic switchgrass

    International Nuclear Information System (INIS)

    Felix, Erika; Tilley, David R.

    2009-01-01

    Ethanol production from cellulosic sources such as switchgrass (Panicum virgatum L.) requires the use of natural resources, fossil fuels, electricity, and human-derived goods and services. We used emergy accounting to integrate the ultimate amount of environmental, fossil fuel, and human-derived energy required to produce ethanol from switchgrass. Emergy is the total amount of energy of one form required directly and indirectly to make another form of energy. Forty-four percent of required emergy came from the environment either directly or embodied in purchased goods, 30% came from fossil fuels either directly or embodied in purchased goods, and 25% came from human-derived services indirectly. Ethanol production per petroleum use (emergy/emergy) was 4.0-to-1 under our Baseline Scenario, but dropped to 0.5-to-1 under a scenario that assumed higher input prices, lower conversion efficiencies and less waste recycling. At least 75% of total emergy was from non-renewable sources. Energy 'hidden' in indirect paths such as goods and services was 65% of the total. Cellulosic-ethanol is not a primary fuel source that substitutes for petroleum because its production relies heavily on non-renewable energy and purchased inputs. It is a means for converting natural resources to liquid fuel. (author)

  4. Simultaneous cell growth and ethanol production from cellulose by an engineered yeast consortium displaying a functional mini-cellulosome

    Directory of Open Access Journals (Sweden)

    Madan Bhawna

    2011-11-01

    Full Text Available Abstract Background The recalcitrant nature of cellulosic materials and the high cost of enzymes required for efficient hydrolysis are the major impeding steps to their practical usage for ethanol production. Ideally, a recombinant microorganism, possessing the capability to utilize cellulose for simultaneous growth and ethanol production, is of great interest. We have reported recently the use of a yeast consortium for the functional presentation of a mini-cellulosome structure onto the yeast surface by exploiting the specific interaction of different cohesin-dockerin pairs. In this study, we engineered a yeast consortium capable of displaying a functional mini-cellulosome for the simultaneous growth and ethanol production on phosphoric acid swollen cellulose (PASC. Results A yeast consortium composed of four different populations was engineered to display a functional mini-cellulosome containing an endoglucanase, an exoglucanase and a β-glucosidase. The resulting consortium was demonstrated to utilize PASC for growth and ethanol production. The final ethanol production of 1.25 g/L corresponded to 87% of the theoretical value and was 3-fold higher than a similar yeast consortium secreting only the three cellulases. Quantitative PCR was used to enumerate the dynamics of each individual yeast population for the two consortia. Results indicated that the slight difference in cell growth cannot explain the 3-fold increase in PASC hydrolysis and ethanol production. Instead, the substantial increase in ethanol production is consistent with the reported synergistic effect on cellulose hydrolysis using the displayed mini-cellulosome. Conclusions This report represents a significant step towards the goal of cellulosic ethanol production. This engineered yeast consortium displaying a functional mini-cellulosome demonstrated not only the ability to grow on the released sugars from PASC but also a 3-fold higher ethanol production than a similar yeast

  5. The commercial performance of cellulosic ethanol supply-chains in Europe

    Directory of Open Access Journals (Sweden)

    Shah Nilay

    2009-02-01

    Full Text Available Abstract Background The production of fuel-grade ethanol from lignocellulosic biomass resources has the potential to increase biofuel production capacity whilst minimising the negative environmental impacts. These benefits will only be realised if lignocellulosic ethanol production can compete on price with conventional fossil fuels and if it can be produced commercially at scale. This paper focuses on lignocellulosic ethanol production in Europe. The hypothesis is that the eventual cost of production will be determined not only by the performance of the conversion process but by the performance of the entire supply-chain from feedstock production to consumption. To test this, a model for supply-chain cost comparison is developed, the components of representative ethanol supply-chains are described, the factors that are most important in determining the cost and profitability of ethanol production are identified, and a detailed sensitivity analysis is conducted. Results The most important cost determinants are the cost of feedstocks, primarily determined by location and existing markets, and the value obtained for ethanol, primarily determined by the oil price and policy incentives. Both of these factors are highly uncertain. The best performing chains (ethanol produced from softwood and sold as a low percentage blend with gasoline could ultimately be cost competitive with gasoline without requiring subsidy, but production from straw would generally be less competitive. Conclusion Supply-chain design will play a critical role in determining commercial viability. The importance of feedstock supply highlights the need for location-specific assessments of feedstock availability and price. Similarly, the role of subsidies and policy incentives in creating and sustaining the ethanol market highlights the importance of political engagement and the need to include political risks in investment appraisal. For the supply-chains described here, and with

  6. Direct ethanol production from cellulosic materials at high temperature using the thermotolerant yeast Kluyveromyces marxianus displaying cellulolytic enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Yanase, Shuhei; Yamada, Ryosuke; Ogino, Chiaki; Kondo, Akihiko [Kobe Univ. (Japan). Dept. of Chemical Science and Engineering; Hasunuma, Tomohisa; Tanaka, Tsutomu; Fukuda, Hideki [Kobe Univ. (Japan). Organization of Advanced Science and Technology

    2010-09-15

    To exploit cellulosic materials for fuel ethanol production, a microorganism capable of high temperature and simultaneous saccharification-fermentation has been required. However, a major drawback is the optimum temperature for the saccharification and fermentation. Most ethanol-fermenting microbes have an optimum temperature for ethanol fermentation ranging between 28 C and 37 C, while the activity of cellulolytic enzymes is highest at around 50 C and significantly decreases with a decrease in temperature. Therefore, in the present study, a thermotolerant yeast, Kluyveromyces marxianus, which has high growth and fermentation at elevated temperatures, was used as a producer of ethanol from cellulose. The strain was genetically engineered to display Trichoderma reesei endoglucanase and Aspergillus aculeatus {beta}-glucosidase on the cell surface, which successfully converts a cellulosic {beta}-glucan to ethanol directly at 48 C with a yield of 4.24 g/l from 10 g/l within 12 h. The yield (in grams of ethanol produced per gram of {beta}-glucan consumed) was 0.47 g/g, which corresponds to 92.2% of the theoretical yield. This indicates that high-temperature cellulose fermentation to ethanol can be efficiently accomplished using a recombinant K. marxianus strain displaying thermostable cellulolytic enzymes on the cell surface. (orig.)

  7. Next-generation cellulosic ethanol technologies and their contribution to a sustainable Africa.

    Science.gov (United States)

    van Zyl, W H; Chimphango, A F A; den Haan, R; Görgens, J F; Chirwa, P W C

    2011-04-06

    The world is currently heavily dependent on oil, especially in the transport sector. However, rising oil prices, concern about environmental impact and supply instability are among the factors that have led to greater interest in renewable fuel and green chemistry alternatives. Lignocellulose is the only foreseeable renewable feedstock for sustainable production of transport fuels. The main technological impediment to more widespread utilization of lignocellulose for production of fuels and chemicals in the past has been the lack of low-cost technologies to overcome the recalcitrance of its structure. Both biological and thermochemical second-generation conversion technologies are currently coming online for the commercial production of cellulosic ethanol concomitantly with heat and electricity production. The latest advances in biological conversion of lignocellulosics to ethanol with a focus on consolidated bioprocessing are highlighted. Furthermore, integration of cellulosic ethanol production into existing bio-based industries also using thermochemical processes to optimize energy balances is discussed. Biofuels have played a pivotal yet suboptimal role in supplementing Africa's energy requirements in the past. Capitalizing on sub-Saharan Africa's total biomass potential and using second-generation technologies merit a fresh look at the potential role of bioethanol production towards developing a sustainable Africa while addressing food security, human needs and local wealth creation.

  8. Immobilization of Cold-Active Cellulase from Antarctic Bacterium and Its Use for Kelp Cellulose Ethanol Fermentation

    Directory of Open Access Journals (Sweden)

    Yi Bin Wang

    2015-01-01

    Full Text Available Immobilization is an effective way to solve the problem associated with the application of cold-active cellulase in industrial processes. In this study, a cold-active cellulase from the Antarctic psychrophilic bacterium Pseudoalteromonas sp. NJ64 was obtained, immobilized, and analyzed for optimal immobilization conditions. Then it was used in kelp cellulose ethanol fermentation, achieving a higher purity level of kelp cellulose ethanol. The enzymatic activity of this cold-active cellulase was 49.7 U/mL. The optimal immobilization process conditions were as follows: sodium alginate, 30 g/L; calcium chloride, 5 g/L; glutaraldehyde, 0.4%; and cross-linking time, 5 h. Under these conditions, the activity recovery rate was 51.58%. The optimum reaction temperature was at 40 °C, the optimum initial pH was 9.0, and the relative enzyme activity was 58.37% after being recovered seven times. A higher purity level of kelp cellulose ethanol has reached (37.37%. Immobilized cold-active cellulase can effectively hydrolyze the cellulose of kelp residue, which is a valuable component of cellulose bio-ethanol production and will have broad implications in the development of the ethanol industry in China.

  9. [Pretreatment of oil palm residues by dilute alkali for cellulosic ethanol production].

    Science.gov (United States)

    Zhang, Haiyan; Zhou, Yujie; Li, Jinping; Dai, Lingmei; Liu, Dehua; Zhang, Jian'an; Choo, Yuen May; Loh, Soh Kheang

    2013-04-01

    In the study, we used oil palm residues (empty fruit bunch, EFB) as raw material to produce cellulosic ethanol by pretreatment, enzymatic hydrolysis and fermentation. Firstly, the pretreatment of EFB with alkali, alkali/hydrogen peroxide and the effects on the components and enzymatic hydrolysis of cellulose were studied. The results show that dilute alkali was the suitable pretreatment method and the conditions were first to soak the substrate with 1% sodium hydroxide with a solid-liquid ratio of 1:10 at 40 degrees C for 24 h, and then subjected to 121 degrees C for 30 min. Under the conditions, EFB solid recovery was 74.09%, and glucan, xylan and lignin content were 44.08%, 25.74% and 13.89%, respectively. After separated with alkali solution, the pretreated EFB was washed and hydrolyzed for 72 h with 5% substrate concentration and 30 FPU/g dry mass (DM) enzyme loading, and the conversion of glucan and xylan reached 84.44% and 89.28%, respectively. We further investigated the effects of substrate concentration and enzyme loading on enzymatic hydrolysis and ethanol batch simultaneous saccharification and fermentation (SSF). The results show that when enzyme loading was 30 FPU/g DM and substrate concentration was increased from 5% to 25%, ethanol concentration were 9.76 g/L and 35.25 g/L after 72 h fermentation with Saccharomyces cerevisiae (inoculum size 5%, V/V), which was 79.09% and 56.96% of ethanol theory yield.

  10. Use of Byproduct from Cellulosic Ethanol Production as an Additive for Concrete: A Possible Win-win Strategy?

    Directory of Open Access Journals (Sweden)

    Xiangwei Hao

    2015-08-01

    Full Text Available Technologists are facing increasing demands to achieve ecologically sustainable industrial practices. Currently the concrete industry is a significant contributor to greenhouse gas emissions. On the other hand, the scaling up of cellulosic ethanol technology has not been a very easy task. In this context, the integration of “greener” concrete with cellulosic ethanol technology may open up promising possibilities. The solid byproducts from cellulosic ethanol production process have been demonstrated to increase the strength of concrete structures when used as a partial cement replacement. Such a delicate integration can also lead to reduction in both carbon footprint and product cost. The possible commercialization of the integrated technologies would provide win-win benefits for both industries.

  11. Comparing oxidative and dilute acid wet explosion pretreatment of Cocksfoot grass at high dry matter concentration for cellulosic ethanol production

    DEFF Research Database (Denmark)

    Njoku, Stephen Ikechukwu; Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2013-01-01

    into cellulose monomeric C6 sugars was achieved for WEx condition AC-E (180°C, 15 min, and 0.2% sulfuric acid). For that condition, the highest ethanol yield of 197 g/kg DM (97% of theoretical maximum value) was achieved for SSF process by Saccharomyces cerevisiae. However, the highest concentration...... of hemicellulose C5 sugars was found for WEx pretreatment condition O2-A (160°C, 15 min, and 6 bar O2) which means that the highest potential ethanol yield was found at this moderate pretreatment condition with oxygen added. Increasing the pretreatment temperature to 180–190°C with addition of oxygen or dilute...... was investigated for cellulosic ethanol production. The biomass raw materials were pretreated using wet explosion (WEx) at 25% dry matter concentration with addition of oxygen or dilute sulfuric acid. The enzymatic hydrolysis of cellulose was significantly improved after pretreatment. The highest conversion...

  12. Enzymatic hydrolysis of pretreated cellulosic wastes by the cellulase complex of Myceliophthora thermophila D-14 to produce ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Roy, S K; Sadhukhan, R; Raha, S K; Chakrabarty, S L [Bose Institute, Calcutta (India). Dept. of Microbiology

    1991-06-01

    Pretreatment of different cellulosic wastes and their subsequent saccharification by thermostable cellulase from a thermophilic fungus Myceliophthora thermophila D-14 was investigated. Alkali treatment was found to be most effective. Carboxymethyl cellulose and untreated materials were used as controls. Significant inhibition of the cellulase activity was observed in the presence of glucose, but with ethanol no such effect was detected. The conversion of sugar to ethanol varied from 21-50% depending on the nature of substrate used. 14 refs., 2 figs., 4 tabs.

  13. Characterization of persistent colors and decolorization of effluent from biologically treated cellulosic ethanol production wastewater.

    Science.gov (United States)

    Shan, Lili; Liu, Junfeng; Yu, Yanling; Ambuchi, John J; Feng, Yujie

    2016-05-01

    The high chroma of cellulosic ethanol production wastewater poses a serious environmental concern; however, color-causing compounds are still not fully clear. The characteristics of the color compounds and decolorization of biologically treated effluent by electro-catalytic oxidation were investigated in this study. Excitation-emission matrix (EEM), fourier transform infrared spectrometer (FTIR), UV-Vis spectra, and ultrafiltration (UF) fractionation were used to analyze color compounds. High chroma of wastewater largely comes from humic materials, which exhibited great fluorescence proportion (67.1 %) in the biologically treated effluent. Additionally, the color compounds were mainly distributed in the molecular weight fractions with 3-10 and 10-30 kDa, which contributed 53.5 and 34.6 % of the wastewater color, respectively. Further decolorization of biologically treated effluent by electro-catalytic oxidation was investigated, and 98.3 % of color removal accompanied with 97.3 % reduction of humic acid-like matter was achieved after 180 min. The results presented herein will facilitate the development of a well decolorization for cellulosic ethanol production wastewater and better understanding of the biological fermentation.

  14. Lifecycle greenhouse gas implications of US national scenarios for cellulosic ethanol production

    Science.gov (United States)

    Scown, Corinne D.; Nazaroff, William W.; Mishra, Umakant; Strogen, Bret; Lobscheid, Agnes B.; Masanet, Eric; Santero, Nicholas J.; Horvath, Arpad; McKone, Thomas E.

    2012-03-01

    The Energy Independence and Security Act of 2007 set an annual US national production goal of 39.7 billion l of cellulosic ethanol by 2020. This paper explores the possibility of meeting that target by growing and processing Miscanthus × giganteus. We define and assess six production scenarios in which active cropland and/or Conservation Reserve Program land are used to grow to Miscanthus. The crop and biorefinery locations are chosen with consideration of economic, land-use, water management and greenhouse gas (GHG) emissions reduction objectives. Using lifecycle assessment, the net GHG footprint of each scenario is evaluated, providing insight into the climate costs and benefits associated with each scenario’s objectives. Assuming that indirect land-use change is successfully minimized or mitigated, the results suggest two major drivers for overall GHG impact of cellulosic ethanol from Miscanthus: (a) net soil carbon sequestration or emissions during Miscanthus cultivation and (b) GHG offset credits for electricity exported by biorefineries to the grid. Without these factors, the GHG intensity of bioethanol from Miscanthus is calculated to be 11-13 g CO2-equivalent per MJ of fuel, which is 80-90% lower than gasoline. Including soil carbon sequestration and the power-offset credit results in net GHG sequestration up to 26 g CO2-equivalent per MJ of fuel.

  15. Lifecycle greenhouse gas implications of US national scenarios for cellulosic ethanol production

    International Nuclear Information System (INIS)

    Scown, Corinne D; Nazaroff, William W; Strogen, Bret; Santero, Nicholas J; Horvath, Arpad; Mishra, Umakant; Lobscheid, Agnes B; Masanet, Eric; McKone, Thomas E

    2012-01-01

    The Energy Independence and Security Act of 2007 set an annual US national production goal of 39.7 billion l of cellulosic ethanol by 2020. This paper explores the possibility of meeting that target by growing and processing Miscanthus × giganteus. We define and assess six production scenarios in which active cropland and/or Conservation Reserve Program land are used to grow to Miscanthus. The crop and biorefinery locations are chosen with consideration of economic, land-use, water management and greenhouse gas (GHG) emissions reduction objectives. Using lifecycle assessment, the net GHG footprint of each scenario is evaluated, providing insight into the climate costs and benefits associated with each scenario’s objectives. Assuming that indirect land-use change is successfully minimized or mitigated, the results suggest two major drivers for overall GHG impact of cellulosic ethanol from Miscanthus: (a) net soil carbon sequestration or emissions during Miscanthus cultivation and (b) GHG offset credits for electricity exported by biorefineries to the grid. Without these factors, the GHG intensity of bioethanol from Miscanthus is calculated to be 11–13 g CO 2 -equivalent per MJ of fuel, which is 80–90% lower than gasoline. Including soil carbon sequestration and the power-offset credit results in net GHG sequestration up to 26 g CO 2 -equivalent per MJ of fuel. (letter)

  16. Modification of Corn Starch Ethanol Refinery to Efficiently Accept Various High-Impact Cellulosic Feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Derr, Dan [Logos Technologies, Fairfax, VA (United States)

    2013-12-30

    The goal of the Corn-to-Cellulosic Migration (CCM) pilot facility was to demonstrate the implementation of advanced technologies and methods for conversion of non-food, cellulosic feedstocks into ethanol, assess the economics of the facility and evaluate potential environmental benefits for biomass to fuels conversion. The CCM project was comprised of design, build, and operate phases for the CCM pilot facility as well as research & development, and modeling components. The CCM pilot facility was designed to process 1 tonne per day of non-food biomass and biologically convert that biomass to ethanol at a rate of 70 gallons per tonne. The plant demonstrated throughputs in excess of 1 tonne per day for an extended run of 1400 hours. Although target yields were not fully achieved, the continuous operation validated the design and operability of the plant. These designs will permit the design of larger scale operations at existing corn milling operations or for greenfield plants. EdeniQ, a partner in the project and the owner of the pilot plant, continues to operate and evaluate other feedstocks.

  17. Combined enzyme mediated fermentation of cellulose and xylose to ethanol by Schizosaccharomyces pombe, cellulase, [beta]-glucosidase, and xylose isomerase

    Science.gov (United States)

    Lastick, S.M.; Mohagheghi, A.; Tucker, M.P.; Grohmann, K.

    1994-12-13

    A process for producing ethanol from mixed sugar streams from pretreated biomass comprising xylose and cellulose using enzymes to convert these substrates to fermentable sugars; selecting and isolating a yeast Schizosaccharomyces pombe ATCC No. 2476, having the ability to ferment these sugars as they are being formed to produce ethanol; loading the substrates with the fermentation mix composed of yeast, enzymes and substrates; fermenting the loaded substrates and enzymes under anaerobic conditions at a pH range of between about 5.0 to about 6.0 and at a temperature range of between about 35 C to about 40 C until the fermentation is completed, the xylose being isomerized to xylulose, the cellulose being converted to glucose, and these sugars being concurrently converted to ethanol by yeast through means of the anaerobic fermentation; and recovering the ethanol. 2 figures.

  18. Overall process considerations for using dilute acid cellulose hydrolysis technology to produce ethanol from biomass

    International Nuclear Information System (INIS)

    Elander, R.; Ibsen, K.; Hayward, T.; Nagle, N.; Torget, R.

    1997-01-01

    Recent advances in reactors, designed for the dilute acid thermochemical treatment of biomass, have resulted in the development of process alternatives in which both cellulose and hemicellulose are hydrolyzed to soluble sugars in high yields. The optimal extent of cellulose hydrolysis will depend on both the performance and economics of the thermochemical treatment operation, and on subsequent unit operations in the bioethanol production process. Examples of subsequent unit operation interactions include the extent to which cellulase enzymes are used to hydrolyze any remaining cellulose, kinetics and conditions of a largely soluble mixed sugar cofermentation, and the extent to which removal of compounds that inhabit fermenting microorganisms is required. In addition, a number of process operation and economic considerations affect the ultimate economic viability of this type of biomass hydrolysis process. These considerations include reactor design issues to accommodate the kinetic parameters of the various hydrolysis and sugar degradation reactions, liquid volume requirements to achieve acceptable sugar yields, sugar concentrations that result from such a process and their impact on subsequent fermentation volumes and ethanol recovery operations, potential co-product opportunities that result from solubilized lignin, and process steam requirements. Several potential whole-process configurations are presented and key process and economic issues for each are discussed. (author)

  19. Final report (September, 1999--February, 2002) [Public outreach and information dissemination - cellulosic and corn-based ethanol outreach project

    Energy Technology Data Exchange (ETDEWEB)

    Ames, Jeremy; Werner, Carol

    2002-08-01

    EESI's ''Ethanol, Climate Protection, Oil Reduction'' (ECO) electr[on]ic newsletter reaches out to the environmental and agricultural communities, state/local government officials and other interested parties, and provides a forum for dialogue about ''the potential benefits of ethanol--and particularly the expanded opportunities provided by cellulosic ethanol--with a special focus on climate protection.'' Each issue features expert commentary, excerpts from recent studies about ethanol, a summary of current government activity on ethanol, and ''notable quotables.'' The newsletter is distributed primarily via email and is also posted on EESI's web site. EESI also conducts outreach on the benefits of ethanol and other biofuels by attending and speaking at conferences, meetings and workshops around the country. The 16 issues of the newsletter published through December 2001 are included as attachments.

  20. Utilization of Bagasse Cellulose for Ethanol Production through Simultaneous Saccharification and Fermentation by Xylanase

    Directory of Open Access Journals (Sweden)

    M Samsuri

    2010-10-01

    Full Text Available Bagasse is a solid residue from sugar cane process, which is not many use it for some product which have more added value. Bagasse, which is a lignosellulosic material, be able to be use for alternative energy resources like bioethanol or biogas. With renewable energy resources a crisis of energy in Republic of Indonesia could be solved, especially in oil and gas. This research has done the conversion of bagasse to bioethanol with xylanase enzyme. The result show that bagasse contains of 52,7% cellulose, 20% hemicelluloses, and 24,2% lignin. Xylanase enzyme and Saccharomyces cerevisiae was used to hydrolyse and fermentation in SSF process. Variation in this research use pH (4, 4,5, and 5, for increasing ethanol quantity, SSF process was done by added chloride acid (HCl with concentration 0.5% and 1% (v/v and also pre-treatment with white rot fungi such as Lentinus edodes (L.edodes as long 4 weeks. The SSF process was done with 24, 48, 72, and 96 hour's incubation time for fermentation. Variation of pH 4, 4,5, and 5 can produce ethanol with concentrations 2,357 g/L, 2,451 g/L, 2,709 g/L. The added chloride acid (HCl with concentration 0.5% and 1% (v/v and L. edodes can increase ethanol yield, The highest ethanol concentration with added chloride acid (HCl concentration 0.5% and 1% consecutively is 2,967 g/L, 3,249 g/L. The highest ethanol concentration with pre-treatment by L. edodes is 3,202 g/L.

  1. Lampung natural zeolite filled cellulose acetate membrane for pervaporation of ethanol-water mixtures

    Science.gov (United States)

    Iryani, D. A.; Wulandari, N. F.; Cindradewi, AW; Ginting, S. Br; Ernawati, E.; Hasanudin, U.

    2018-03-01

    Pervaporation of ethanol–water can be cost-competitive in the production of renewable biomass ethanol. For the purpose of improving the pervaporation performance of polymeric membranes, we prepared cellulose acetate (CA) filled Lampung Natural Zeolite (LNZ) membranes by incorporating LNZ into CA for pervaporation separation of ethanol-water mixtures. The characteristics and performance of these filled membranes in the varied ratio of CA:LNZ (30:0, 30:5, 30:10, 30: 20, 20:20 and 40:10) wt% were investigated. The prepared membranes were characterized for pervaporation membrane performance such as %water content and membrane swelling degree. Further, the permeation flux and selectivity of membrane were also observed. The results of investigation show that water content of membrane tends to increase with increase of LNZ content. However, the swelling degree of membrane decrease compared than that of CA control membrane. The permeation flux and the selectivity of membranes tend to increase continuously. The CA membrane with ratio of CA:LNZ 30:20 shows the highest selectivity of 80.42 with a permeation flux of 0.986 kg/(m2 h) and ethanol concentration of 99.08 wt%.

  2. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Kazi, F. K.; Fortman, J.; Anex, R.; Kothandaraman, G.; Hsu, D.; Aden, A.; Dutta, A.

    2010-06-01

    A techno-economic analysis on the production of cellulosic ethanol by fermentation was conducted to understand the viability of liquid biofuel production processes within the next 5-8 years. Initially, 35 technologies were reviewed, then a two-step down selection was performed to choose scenarios to be evaluated in a more detailed economic analysis. The lignocellulosic ethanol process was selected because it is well studied and portions of the process have been tested at pilot scales. Seven process variations were selected and examined in detail. Process designs were constrained to public data published in 2007 or earlier, without projecting for future process improvements. Economic analysis was performed for an 'nth plant' (mature technology) to obtain total investment and product value (PV). Sensitivity analysis was performed on PV to assess the impact of variations in process and economic parameters. Results show that the modeled dilute acid pretreatment process without any downstream process variation had the lowest PV of $3.40/gal of ethanol ($5.15/gallon of gasoline equivalent) in 2007 dollars. Sensitivity analysis shows that PV is most sensitive to feedstock and enzyme costs.

  3. Robust cellulosic ethanol production from SPORL-pretreated lodgepole pine using an adapted strain Saccharomyces cervisiae without detoxification

    Science.gov (United States)

    S. Tian; X.L. Luo; X.S. Yang; J.Y. Zhu

    2010-01-01

    This study reports an ethanol yield of 270 L/ton wood from lodgepole pine pretreated with sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) using an adapted strain, Saccharomyces cerevisiae Y5, without detoxification. The enzymatic hydrolysate produced from pretreated cellulosic solids substrate was combined with pretreatment hydrolysate before...

  4. Evaluation of mountain beetle-infested lodgepole pine for cellulosic ethanol production by sulfite pretreatment to overcome recalcitrance of lignocellulose

    Science.gov (United States)

    X. Luo; R. Gleisner; S. Tian; J. Negron; W. Zhu; E. Horn; X. J. Pan; J. Y. Zhu

    2010-01-01

    The potentials of deteriorated mountain pine beetle (Dendroctonus ponderosae)-killed lodgepole pine (Pinus contorta) trees for cellulosic ethanol production were evaluated using the sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) process. The trees were harvested from two sites in the United States Arapaho-Roosevelt National Forest, Colorado....

  5. Cellulosic ethanol production via consolidated bioprocessing by a novel thermophilic anaerobic bacterium isolated from a Himalayan hot spring.

    Science.gov (United States)

    Singh, Nisha; Mathur, Anshu S; Tuli, Deepak K; Gupta, Ravi P; Barrow, Colin J; Puri, Munish

    2017-01-01

    Cellulose-degrading thermophilic anaerobic bacterium as a suitable host for consolidated bioprocessing (CBP) has been proposed as an economically suited platform for the production of second-generation biofuels. To recognize the overall objective of CBP, fermentation using co-culture of different cellulolytic and sugar-fermenting thermophilic anaerobic bacteria has been widely studied as an approach to achieving improved ethanol production. We assessed monoculture and co-culture fermentation of novel thermophilic anaerobic bacterium for ethanol production from real substrates under controlled conditions. In this study, Clostridium sp. DBT-IOC-C19, a cellulose-degrading thermophilic anaerobic bacterium, was isolated from the cellulolytic enrichment cultures obtained from a Himalayan hot spring. Strain DBT-IOC-C19 exhibited a broad substrate spectrum and presented single-step conversion of various cellulosic and hemicellulosic substrates to ethanol, acetate, and lactate with ethanol being the major fermentation product. Additionally, the effect of varying cellulose concentrations on the fermentation performance of the strain was studied, indicating a maximum cellulose utilization ability of 10 g L -1 cellulose. Avicel degradation kinetics of the strain DBT-IOC-C19 displayed 94.6% degradation at 5 g L -1 and 82.74% degradation at 10 g L -1 avicel concentration within 96 h of fermentation. In a comparative study with Clostridium thermocellum DSM 1313, the ethanol and total product concentrations were higher by the newly isolated strain on pretreated rice straw at an equivalent substrate loading. Three different co-culture combinations were used on various substrates that presented two-fold yield improvement than the monoculture during batch fermentation. This study demonstrated the direct fermentation ability of the novel thermophilic anaerobic bacteria on various cellulosic and hemicellulosic substrates into ethanol without the aid of any exogenous enzymes

  6. Optical Sensor based Chemical Modification as a Porous Cellulose Acetate Film and Its Application for Ethanol Sensor

    Science.gov (United States)

    Mulijani, S.; Iswantini, D.; Wicaksono, R.; Notriawan, D.

    2018-03-01

    A new approach to design and construction of an optical ethanol sensor has been developed by immobilizing a direct dye at a porous cellulosic polymer fllm. This sensor was fabricated by binding Nile Red to a cellulose acetate membrane that had previously been subjected to an exhaustive base hydrolysis. The prepared optical ethanol sensor was enhanced by adding pluronic as a porogen in the membrane. The addition of pluronic surfactant into cellulose acetate membrane increased the hydrophilic and porous properties of membrane. Advantageous features of the design include simple and easy of fabrication. Variable affecting sensor performance of dye concentration have been fully evaluated and optimized. The rapid response results from the porous structure of the polymeric support, which minimizes barriers to mass transport. Signal of optical sensor based on reaction of dye nile red over the membrane with ethanol and will produce the purple colored product. Result was obtained that maximum intensity of dye nile red reacted with alcohol is at 630-640 nm. Linear regression equation (r2), limit of detection, and limit of quantitation of membrane with 2% dye was 0.9625, 0.29%, and 0.97%. Performance of optical sensor was also evaluated through methanol, ethanol and propanol. This study was purposed to measure the polarity and selectivity of optic sensor toward the alcohol derivatives. Fluorescence intensity of optic sensor membrane for methanol 5%, ethanol 5% and propanol 5% was 15113.56, 16573.75 and 18495.97 respectively.

  7. Metabolic engineering of a haploid strain derived from a triploid industrial yeast for producing cellulosic ethanol.

    Science.gov (United States)

    Kim, Soo Rin; Skerker, Jeffrey M; Kong, In Iok; Kim, Heejin; Maurer, Matthew J; Zhang, Guo-Chang; Peng, Dairong; Wei, Na; Arkin, Adam P; Jin, Yong-Su

    2017-03-01

    Many desired phenotypes for producing cellulosic biofuels are often observed in industrial Saccharomyces cerevisiae strains. However, many industrial yeast strains are polyploid and have low spore viability, making it difficult to use these strains for metabolic engineering applications. We selected the polyploid industrial strain S. cerevisiae ATCC 4124 exhibiting rapid glucose fermentation capability, high ethanol productivity, strong heat and inhibitor tolerance in order to construct an optimal yeast strain for producing cellulosic ethanol. Here, we focused on developing a general approach and high-throughput screening method to isolate stable haploid segregants derived from a polyploid parent, such as triploid ATCC 4124 with a poor spore viability. Specifically, we deleted the HO genes, performed random sporulation, and screened the resulting segregants based on growth rate, mating type, and ploidy. Only one stable haploid derivative (4124-S60) was isolated, while 14 other segregants with a stable mating type were aneuploid. The 4124-S60 strain inherited only a subset of desirable traits present in the parent strain, same as other aneuploids, suggesting that glucose fermentation and specific ethanol productivity are likely to be genetically complex traits and/or they might depend on ploidy. Nonetheless, the 4124-60 strain did inherit the ability to tolerate fermentation inhibitors. When additional genetic perturbations known to improve xylose fermentation were introduced into the 4124-60 strain, the resulting engineered strain (IIK1) was able to ferment a Miscanthus hydrolysate better than a previously engineered laboratory strain (SR8), built by making the same genetic changes. However, the IIK1 strain showed higher glycerol and xylitol yields than the SR8 strain. In order to decrease glycerol and xylitol production, an NADH-dependent acetate reduction pathway was introduced into the IIK1 strain. By consuming 2.4g/L of acetate, the resulting strain (IIK1A

  8. Influence of sugarcane bagasse variability on sugar recovery for cellulosic ethanol production.

    Science.gov (United States)

    Andrade, Liliane Pires; Crespim, Elaine; de Oliveira, Nilton; de Campos, Rafael Carinha; Teodoro, Juliana Conceição; Galvão, Célia Maria Araújo; Maciel Filho, Rubens

    2017-10-01

    In the context of cellulosic ethanol production, special attention must be given to the raw material, as it affects final product yield. As observed for sugarcane, bagasse variations may derive from several elements, for instance edaphoclimatic factors, seasonality, maturation stage and harvesting techniques. Therefore, in the present work, to investigate the impact of raw material characteristics on process performance, sugarcane bagasse from four harvests from October/2010 to October/2011 was pretreated by steam explosion and had its soluble and insoluble solids contents measured, following enzymatic hydrolysis to assess glucan conversion. As confirmed by ANOVA, glucose concentration was related to the solids content in the reactor, whereas glucan conversion was related to the enzymatic load. Variations in raw material composition were indeed observed to significantly interfere in the final sugar recovery, probably due to the increase in the impurities observed as a result of the type of harvest performed in 2011. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Cultivar variation and selection potential relevant to the production of cellulosic ethanol from wheat straw

    DEFF Research Database (Denmark)

    Lindedam, Jane; Andersen, Sven Bode; DeMartini, J.

    2012-01-01

    Optimizing cellulosic ethanol yield depends strongly on understanding the biological variation of feedstocks. Our objective was to study variation in capacity for producing fermentable sugars from straw of winter wheat cultivars with a high-throughput pretreatment and hydrolysis well......-plate technique. This technique enabled us to estimate cultivar-related and environmental correlations between sugar yield, chemical composition, agronomic qualities, and distribution of botanical plant parts of wheat straw cultivars. Straws from 20 cultivars were collected in duplicates on two sites in Denmark....... Following hydrothermal pretreatment (180 °C for 17.6 min) and co-hydrolysis, sugar release and sugar conversion were measured. Up to 26% difference in sugar release between cultivars was observed. Sugar release showed negative cultivar correlation with lignin and ash content, whereas sugar release showed...

  10. Novel heat–integrated and intensified biorefinery process for cellulosic ethanol production from lignocellulosic biomass

    International Nuclear Information System (INIS)

    Nhien, Le Cao; Long, Nguyen Van Duc; Lee, Moonyong

    2017-01-01

    Highlights: • A compact biorefinery design was proposed for cellulosic ethanol purification. • Actual fermentation broth from lignocellulosic biomass was considered. • Process integration and intensification achieves competitive biorefinery context. • The response surface method optimizes the complex column structure effectively. • The proposed process could save up to 47.6% of total annual cost. - Abstract: Biofuels have the most potential as an alternative to fossil fuels and overcoming global warming, which has become one of the most serious environmental issues over the past few decades. As the world confronts food shortages due to an increase in world population, the development of biofuels from inedible lignocellulosic feedstock may be more sustainable in the long term. Inspired by the NREL conventional process, this paper proposes a novel heat–integrated and intensified biorefinery design for cellulosic ethanol production from lignocellulosic biomass. For the preconcentration section, heat pump assisted distillation and double–effect heat integration were evaluated, while a combination of heat–integrated technique and intensified technique, extractive dividing wall column (EDWC), was applied to enhance the process energy and cost efficiency for the purification section. A biosolvent, glycerol, which can be produced from biodiesel production, was used as the extracting solvent in an EDWC to obtain a high degree of integration in a biorefinery context. All configuration alternatives were simulated rigorously using Aspen Plus were based on the energy requirements, total annual costs (TAC), and total carbon dioxide emissions (TCE). In addition, the structure of the EDWC was optimized using the reliable response surface method, which was carried out using Minitab statistical software. The simulation results showed that the proposed heat–integrated and intensified process can save up to 47.6% and 56.9% of the TAC and TCE for the purification

  11. Chemical Pretreatment Methods for the Production of Cellulosic Ethanol: Technologies and Innovations

    Directory of Open Access Journals (Sweden)

    Edem Cudjoe Bensah

    2013-01-01

    Full Text Available Pretreatment of lignocellulose has received considerable research globally due to its influence on the technical, economic and environmental sustainability of cellulosic ethanol production. Some of the most promising pretreatment methods require the application of chemicals such as acids, alkali, salts, oxidants, and solvents. Thus, advances in research have enabled the development and integration of chemical-based pretreatment into proprietary ethanol production technologies in several pilot and demonstration plants globally, with potential to scale-up to commercial levels. This paper reviews known and emerging chemical pretreatment methods, highlighting recent findings and process innovations developed to offset inherent challenges via a range of interventions, notably, the combination of chemical pretreatment with other methods to improve carbohydrate preservation, reduce formation of degradation products, achieve high sugar yields at mild reaction conditions, reduce solvent loads and enzyme dose, reduce waste generation, and improve recovery of biomass components in pure forms. The use of chemicals such as ionic liquids, NMMO, and sulphite are promising once challenges in solvent recovery are overcome. For developing countries, alkali-based methods are relatively easy to deploy in decentralized, low-tech systems owing to advantages such as the requirement of simple reactors and the ease of operation.

  12. Bioethanol Production From Cellulose by Candida tropicalis, as An Alternative Microbial Agent to Produce Ethanol from Lignocellulosic Biomass

    Directory of Open Access Journals (Sweden)

    Hermansyah

    2016-04-01

    Full Text Available Abstract: Candida tropicalis isolated from Tuak is a potentially useful microorganism for the ethanol production from lignocellulosic biomass and it can be alterbative agent replacing Saccharomyces cerevisae for fermentation process. Although C.tropicalis could not convert all carbohydrates content of lignocellulosic into bioethanol, however it is able to grow on medium in the presence of either xylose or arabinose as carbon source. Our result showed that fermentation of 10 % (w/v cellulosic as sole carbon source produced 2.88% (v/v ethanol by C.tropicalis. This ethanol production was lower than usage of 10% (w/v dextrose as sole carbon source medium which producing 5.51% (v/v ethanol. Based upon our expreiment indicated that C.tropicalis is able to conduct two main process in converting of cellulosic material- to ethanol which is hydrolysis the degradation of cellulose into glucose, and fermentation the process the conversion glucose into bioethanol. Keywords : Candida tropicalis, bioethanol, fermentation, cellulosic Abstrak (Indonesian: Candida tropicalis yang diisiolasi dari Tuak adalah agen yang berpotensi dalam produksi etanol dari biomasa lignoselulosa dan dapat dijadikan agen alternatif menggantikan Saccharomyces cerevisiae pada proses fernentasi. Walaupun C.tropicalis tidak dapat mengkonversi semua kandungan karbohidrat lignoselulosamenjadi etanol, akan tetapi C.tropicalis mampu tumbuh pada media dengan xilosa atau arabinosa sebagaisumber karbon. Hasil kami menunjukkan bahwa dengan mengguankan C.tropicalis fermentasi 10% (w/v selulosa sebagai satu-satunya sumber karbon menghasilkan 2,88% (v/v etanol, Produksi etanol ini lebih rendah jika menggunakan 10% (w/v dekstrosa sebagai satu satunya sumber karbon yang menghasilkan 5,51% (v/v etanol. Berdasarkan percobaan menunjukkan bahwa C.tropicalis mampu melakukan dua proses utama dalam mengkonversi material selulosa menjadi etanol yaitu hidrolisis degradasi selulosa menjadi glukosa, dan

  13. Combined inactivation of the Clostridium cellulolyticum lactate and malate dehydrogenase genes substantially increases ethanol yield from cellulose and switchgrass fermentations

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yongchao [ORNL; Tschaplinski, Timothy J [ORNL; Engle, Nancy L [ORNL; Hamilton, Choo Yieng [ORNL; Rodriguez, Jr., Miguel [ORNL; Liao, James C [ORNL; Schadt, Christopher Warren [ORNL; Guss, Adam M [ORNL; Yang, Yunfeng [ORNL; Graham, David E [ORNL

    2012-01-01

    Background: The model bacterium Clostridium cellulolyticum efficiently hydrolyzes crystalline cellulose and hemicellulose, using cellulosomes to degrade lignocellulosic biomass. Although it imports and ferments both pentose and hexose sugars to produce a mixture of ethanol, acetate, lactate, H2 and CO2, the proportion of ethanol is low, which impedes its use in consolidated bioprocessing for biofuels. Therefore genetic engineering will likely be required to improve the ethanol yield. Random mutagenesis, plasmid transformation, and heterologous expression systems have previously been developed for C. cellulolyticum, but targeted mutagenesis has not been reported for this organism. Results: The first targeted gene inactivation system was developed for C. cellulolyticum, based on a mobile group II intron originating from the Lactococcus lactis L1.LtrB intron. This markerless mutagenesis system was used to disrupt both the paralogous L-lactate dehydrogenase (Ccel_2485; ldh) and L-malate dehydrogenase (Ccel_0137; mdh) genes, distinguishing the overlapping substrate specificities of these enzymes. Both mutations were then combined in a single strain. This double mutant produced 8.5-times more ethanol than wild-type cells growing on crystalline cellulose. Ethanol constituted 93% of the major fermentation products (by molarity), corresponding to a molar ratio of ethanol to organic acids of 15, versus 0.18 in wild-type cells. During growth on acid-pretreated switchgrass, the double mutant also produced four-times as much ethanol as wild-type cells. Detailed metabolomic analyses identified increased flux through the oxidative branch of the mutant s TCA pathway. Conclusions: The efficient intron-based gene inactivation system produced the first gene-targeted mutations in C. cellulolyticum. As a key component of the genetic toolbox for this bacterium, markerless targeted mutagenesis enables functional genomic research in C. cellulolyticum and rapid genetic engineering to

  14. Cost evaluation of cellulase enzyme for industrial-scale cellulosic ethanol production based on rigorous Aspen Plus modeling.

    Science.gov (United States)

    Liu, Gang; Zhang, Jian; Bao, Jie

    2016-01-01

    Cost reduction on cellulase enzyme usage has been the central effort in the commercialization of fuel ethanol production from lignocellulose biomass. Therefore, establishing an accurate evaluation method on cellulase enzyme cost is crucially important to support the health development of the future biorefinery industry. Currently, the cellulase cost evaluation methods were complicated and various controversial or even conflict results were presented. To give a reliable evaluation on this important topic, a rigorous analysis based on the Aspen Plus flowsheet simulation in the commercial scale ethanol plant was proposed in this study. The minimum ethanol selling price (MESP) was used as the indicator to show the impacts of varying enzyme supply modes, enzyme prices, process parameters, as well as enzyme loading on the enzyme cost. The results reveal that the enzyme cost drives the cellulosic ethanol price below the minimum profit point when the enzyme is purchased from the current industrial enzyme market. An innovative production of cellulase enzyme such as on-site enzyme production should be explored and tested in the industrial scale to yield an economically sound enzyme supply for the future cellulosic ethanol production.

  15. Modeling and analysing storage systems in agricultural biomass supply chain for cellulosic ethanol production

    International Nuclear Information System (INIS)

    Ebadian, Mahmood; Sowlati, Taraneh; Sokhansanj, Shahab; Townley-Smith, Lawrence; Stumborg, Mark

    2013-01-01

    Highlights: ► Studied the agricultural biomass supply chain for cellulosic ethanol production. ► Evaluated the impact of storage systems on different supply chain actors. ► Developed a combined simulation/optimization model to evaluate storage systems. ► Compared two satellite storage systems with roadside storage in terms of costs and emitted CO 2 . ► SS would lead to a more cost-efficient supply chain compared to roadside storage. -- Abstract: In this paper, a combined simulation/optimization model is developed to better understand and evaluate the impact of the storage systems on the costs incurred by each actor in the agricultural biomass supply chain including farmers, hauling contractors and the cellulosic ethanol plant. The optimization model prescribes the optimum number and location of farms and storages. It also determines the supply radius, the number of farms required to secure the annual supply of biomass and also the assignment of farms to storage locations. Given the specific design of the supply chain determined by the optimization model, the simulation model determines the number of required machines for each operation, their daily working schedule and utilization rates, along with the capacities of storages. To evaluate the impact of the storage systems on the delivered costs, three storage systems are molded and compared: roadside storage (RS) system and two satellite storage (SS) systems including SS with fixed hauling distance (SF) and SS with variable hauling distance (SV). In all storage systems, it is assumed the loading equipment is dedicated to storage locations. The obtained results from a real case study provide detailed cost figures for each storage system since the developed model analyses the supply chain on an hourly basis and considers time-dependence and stochasticity of the supply chain. Comparison of the storage systems shows SV would outperform SF and RS by reducing the total delivered cost by 8% and 6%, respectively

  16. Ethanol extract grapefruit peel ( Citrus maxima Murr.) gel formulations with gelling agent durian seed gum and carboxy methyl cellulose

    OpenAIRE

    Nazliniwaty; Karsono; Zebua, Nilsya Febrika; Nerdy

    2017-01-01

    This research aims to investigate the best gel formula of grapefruit ethanol extracts (Citrus maxima Murr.) with gelling agent combination durian seed gum and carboxy methyl cellulose (CMC). Durian seed gum was isolated with centrifuge and then combined with CMC-Na in five formulas. Evaluation material of topical gel that is its homogeneity, pH, stability testing, and irritation of the volunteers. All formula gel preparations its ...

  17. Current Pretreatment Technologies for the Development of Cellulosic Ethanol and Biorefineries.

    Science.gov (United States)

    Silveira, Marcos Henrique Luciano; Morais, Ana Rita C; da Costa Lopes, Andre M; Olekszyszen, Drielly Nayara; Bogel-Łukasik, Rafał; Andreaus, Jürgen; Pereira Ramos, Luiz

    2015-10-26

    Lignocellulosic materials, such as forest, agriculture, and agroindustrial residues, are among the most important resources for biorefineries to provide fuels, chemicals, and materials in such a way to substitute for, at least in part, the role of petrochemistry in modern society. Most of these sustainable biorefinery products can be produced from plant polysaccharides (glucans, hemicelluloses, starch, and pectic materials) and lignin. In this scenario, cellulosic ethanol has been considered for decades as one of the most promising alternatives to mitigate fossil fuel dependence and carbon dioxide accumulation in the atmosphere. However, a pretreatment method is required to overcome the physical and chemical barriers that exist in the lignin-carbohydrate composite and to render most, if not all, of the plant cell wall components easily available for conversion into valuable products, including the fuel ethanol. Hence, pretreatment is a key step for an economically viable biorefinery. Successful pretreatment method must lead to partial or total separation of the lignocellulosic components, increasing the accessibility of holocellulose to enzymatic hydrolysis with the least inhibitory compounds being released for subsequent steps of enzymatic hydrolysis and fermentation. Each pretreatment technology has a different specificity against both carbohydrates and lignin and may or may not be efficient for different types of biomasses. Furthermore, it is also desirable to develop pretreatment methods with chemicals that are greener and effluent streams that have a lower impact on the environment. This paper provides an overview of the most important pretreatment methods available, including those that are based on the use of green solvents (supercritical fluids and ionic liquids). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Combined inactivation of the Clostridium cellulolyticum lactate and malate dehydrogenase genes substantially increases ethanol yield from cellulose and switchgrass fermentations

    Directory of Open Access Journals (Sweden)

    Li Yongchao

    2012-01-01

    Full Text Available Abstract Background The model bacterium Clostridium cellulolyticum efficiently degrades crystalline cellulose and hemicellulose, using cellulosomes to degrade lignocellulosic biomass. Although it imports and ferments both pentose and hexose sugars to produce a mixture of ethanol, acetate, lactate, H2 and CO2, the proportion of ethanol is low, which impedes its use in consolidated bioprocessing for biofuels production. Therefore genetic engineering will likely be required to improve the ethanol yield. Plasmid transformation, random mutagenesis and heterologous expression systems have previously been developed for C. cellulolyticum, but targeted mutagenesis has not been reported for this organism, hindering genetic engineering. Results The first targeted gene inactivation system was developed for C. cellulolyticum, based on a mobile group II intron originating from the Lactococcus lactis L1.LtrB intron. This markerless mutagenesis system was used to disrupt both the paralogous L-lactate dehydrogenase (Ccel_2485; ldh and L-malate dehydrogenase (Ccel_0137; mdh genes, distinguishing the overlapping substrate specificities of these enzymes. Both mutations were then combined in a single strain, resulting in a substantial shift in fermentation toward ethanol production. This double mutant produced 8.5-times more ethanol than wild-type cells growing on crystalline cellulose. Ethanol constituted 93% of the major fermentation products, corresponding to a molar ratio of ethanol to organic acids of 15, versus 0.18 in wild-type cells. During growth on acid-pretreated switchgrass, the double mutant also produced four times as much ethanol as wild-type cells. Detailed metabolomic analyses identified increased flux through the oxidative branch of the mutant's tricarboxylic acid pathway. Conclusions The efficient intron-based gene inactivation system produced the first non-random, targeted mutations in C. cellulolyticum. As a key component of the genetic toolbox

  19. Liquid fuel resources and prospects for ligno-cellulosic ethanol: An Egyptian case study

    Directory of Open Access Journals (Sweden)

    Shadia R. Tewfik

    2013-12-01

    Full Text Available Fossil fuels (oil, natural gas and coal presently represent about 90% of the world’s total commercial primary energy demand. Yet, they are depletable sources of energy. Growth in the production of easily accessible oil, the main source of high energy liquid transportation fuels, will not match the projected rate of demand growth, especially in developing countries. In the transport sector, today, the only alternative to non-sustainable fossil fuels is biofuels that are produced from biomass, a stored environmentally neutral solar energy. These fuels are compatible with current vehicles and blendable with conventional fuels. Moreover, they share the long-established distribution infrastructure with little, if any, modification of equipment. The main biofuels presently in commercial production are bioethanol and biodiesel. Industrial countries started production of the 1st generation bioethanol and biodiesel from food products (grains and edible oil since a few decades and these fuels are currently available at petrol stations. Second generation bioethanol from ligno-cellulosic materials is on the research, pilot and/or demonstration stage. This paper discusses the current situation regarding liquid fuels in Egypt which are experiencing imbalance between total production and demand for gasoline and diesel fuels. The quantified need for nonconventional sources is presented. Based on a thorough assessment of current and prospective generated agriculture residues as distributed over the political areas, mapping of the number and capacity of plants to be installed for production of bioethanol from available residues namely rice straw, sugar cane residues and cotton stalks has been developed. Annual capacities of 3000, 10,000 and 20,000 tons ethanol/year until year 2021 have been proposed. Capital and operating requirements and economic indicators have been estimated. It has been concluded that at current price of ethanol of about $0.6/kg, the

  20. Oxidative production of xylonic acid using xylose in distillation stillage of cellulosic ethanol fermentation broth by Gluconobacter oxydans.

    Science.gov (United States)

    Zhang, Hongsen; Han, Xushen; Wei, Chengxiang; Bao, Jie

    2017-01-01

    An oxidative production process of xylonic acid using xylose in distillation stillage of cellulosic ethanol fermentation broth was designed, experimentally investigated, and evaluated. Dry dilute acid pretreated and biodetoxified corn stover was simultaneously saccharified and fermented into 59.80g/L of ethanol (no xylose utilization). 65.39g/L of xylose was obtained in the distillation stillage without any concentrating step after ethanol was distillated. Then the xylose was completely converted into 66.42g/L of xylonic acid by Gluconobacter oxydans. The rigorous Aspen Plus modeling shows that the wastewater generation and energy consumption was significantly reduced comparing to the previous xylonic acid production process using xylose in pretreatment liquid. This study provided a practical process option for xylonic acid production from lignocellulose feedstock with significant reduction of wastewater and energy consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Enhanced cellulase recovery without β-glucosidase supplementation for cellulosic ethanol production using an engineered strain and surfactant.

    Science.gov (United States)

    Huang, Renliang; Guo, Hong; Su, Rongxin; Qi, Wei; He, Zhimin

    2017-03-01

    Recycling cellulases by substrate adsorption is a promising strategy for reducing the enzyme cost of cellulosic ethanol production. However, β-glucosidase has no carbohydrate-binding module (CBM). Thus, additional enzymes are required in each cycle to achieve a high ethanol yield. In this study, we report a new method of recycling cellulases without β-glucosidase supplementation using lignocellulosic substrate, an engineered strain expressing β-glucosidase and Tween 80. The cellulases and Tween 80 were added to an aqueous suspension of diluted sulfuric acid/ammonia-treated corncobs in a simultaneous saccharification and fermentation (SSF) process for ethanol production. Subsequently, the addition of fresh pretreated corncobs to the fermentation liquor and remaining solid residue provided substrates with absorbed cellulases for the next SSF cycle. This method provided excellent ethanol production in three successive SSF cycles without requiring the addition of new cellulases. For a 10% (w/v) solid loading, a cellulase dosage of 30 filter paper units (FPU)/g cellulose, 0.5% Tween 80, and 2 g/L of the engineered strain, approximately 90% of the initial ethanol concentration from the first SSF process was obtained in the next two SSF processes, with a total ethanol production of 306.27 g/kg corncobs and an enzyme productivity of 0.044 g/FPU. Tween 80 played an important role in enhancing cellulase recovery. This new enzyme recycling method is more efficient and practical than other reported methods. Biotechnol. Bioeng. 2017;114: 543-551. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Evaluation of environmental impacts of cellulosic ethanol using life cycle assessment with technological advances over time

    International Nuclear Information System (INIS)

    Pawelzik, Paul F.; Zhang, Qiong

    2012-01-01

    Life Cycle Assessment (LCA) has been used in quantifying the environmental impacts of materials, processes, products, or systems across their entire lifespan from creation to disposal. To evaluate the environmental impact of advancing technology, Life Cycle Assessment with Technological Advances over Time (LCA-TAT) incorporates technology improvements within the traditional LCA framework. In this paper, the LCA-TAT is applied to quantify the environmental impacts of ethanol production using cellulosic biomass as a feedstock through the simultaneous saccharification and co-fermentation (SSCF) process as it improves over time. The data for the SSCF process are taken from the Aspen Plus ® simulation developed by the National Renewable Energy Lab (NREL). The Environmental Fate and Risk Assessment Tool (EFRAT) is used to calculate the fugitive emissions and SimaPro 7.1 software is used to quantify the environmental impacts of processes. The impact indicators of the processes are calculated using the Eco-indicator 95 method; impact categories analyzed include ozone layer depletion, heavy metals, carcinogens, summer smog, winter smog, pesticides, greenhouse effect, acidification, and eutrophication. Based on the LCA-TAT results, it is found that removal of the continuous ion exchange step within the pretreatment area increases the environmental impact of the process. The main contributor to the increase in the environmental impact of the process is the heavy metal indicator. In addition, a sensitivity analysis is performed to identify major inputs and outputs that affect environmental impacts of the overall process. Based on this analysis it is observed that an increase in waste production and acid use have the greatest effect on the environmental impacts of the SSCF process. Comparing economic analysis with projected technological advances performed by NREL, the improvement in environmental impact was not matched by a concomitant improvement in economic performance. In

  3. Robust cellulosic ethanol production from SPORL-pretreated lodgepole pine using an adapted strain Saccharomyces cerevisiae without detoxification.

    Science.gov (United States)

    Tian, S; Luo, X L; Yang, X S; Zhu, J Y

    2010-11-01

    This study reports an ethanol yield of 270L/ton wood from lodgepole pine pretreated with sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) using an adapted strain, Saccharomyces cerevisiae Y5, without detoxification. The enzymatic hydrolysate produced from pretreated cellulosic solids substrate was combined with pretreatment hydrolysate before fermentation. Detoxification of the pretreatment hydrolysate using overliming or XAD-4 resin before being combined with enzymatic hydrolysate improved ethanol productivity in the first 4h of fermentation and overall fermentation efficiency. However, detoxification did not improve final ethanol yield because of sugar losses. The Y5 strain showed excellent ethanol productivities of 2.0 and 0.8g/L/h averaged over a period of 4 and 24h, respectively, in the undetoxified run. The furan metabolization rates of the Y5 strain were significantly higher for the undetoxified run than those for the detoxidfied runs, suggesting it can tolerate even higher furan concentrations than those studied. Preliminary mass and energy balances were conducted. SPORL produced an excellent monomeric sugar recovery value of about 85% theoretical and a net energy output of 4.05GJ/ton wood with an ethanol energy production efficiency of 178% before distillation.

  4. Synergetic effect of yeast cell-surface expression of cellulase and expansin-like protein on direct ethanol production from cellulose

    Science.gov (United States)

    2013-01-01

    Background Numerous studies have examined the direct fermentation of cellulosic materials by cellulase-expressing yeast; however, ethanol productivity in these systems has not yet reached an industrial level. Certain microorganisms, such as the cellulolytic fungus Trichoderma reesei, produce expansin-like proteins, which have a cellulose-loosening effect that may increase the breakdown of cellulose. Here, to improve the direct conversion of cellulose to ethanol, yeast Saccharomyces cerevisiae co-displaying cellulase and expansin-like protein on the cell surface were constructed and examined for direct ethanol fermentation performance. Results The cellulase and expansin-like protein co-expressing strain showed 246 mU/g-wet cell of phosphoric acid swollen cellulose (PASC) degradation activity, which corresponded to 2.9-fold higher activity than that of a cellulase-expressing strain. This result clearly demonstrated that yeast cell-surface expressed cellulase and expansin-like protein act synergistically to breakdown cellulose. In fermentation experiments examining direct ethanol production from PASC, the cellulase and expansin-like protein co-expressing strain produced 3.4 g/L ethanol after 96 h of fermentation, a concentration that was 1.4-fold higher than that achieved by the cellulase-expressing strain (2.5 g/L). Conclusions The PASC degradation and fermentation ability of an engineered yeast strain was markedly improved by co-expressing cellulase and expansin-like protein on the cell surface. To our knowledge, this is the first report to demonstrate the synergetic effect of co-expressing cellulase and expansin-like protein on a yeast cell surface, which may be a promising strategy for constructing direct ethanol fermenting yeast from cellulose. PMID:23835302

  5. Removal of the Fermentation Inhibitor, Furfural, Using Activated Carbon in Cellulosic-Ethanol Production

    KAUST Repository

    Zhang, Kuang; Agrawal, Manoj; Harper, Justin; Chen, Rachel; Koros, William J.

    2011-01-01

    Ethanol can be produced from lignocellulosic biomass through fermentation; however, some byproducts from lignocellulosics, such as furfural compounds, are highly inhibitory to the fermentation and can substantially reduce the efficiency of ethanol

  6. Fed-batch culture for the direct conversion of cellulosic substrates to acetic acid/ethanol by Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, P.K.R.; Singh, A.; Schuegerl, K. (Hannover Univ. (Germany). Inst. fuer Technische Chemie)

    1991-01-01

    The production of acetic acid/ethanol and hydrolytic enzymes from potato waste (cellulosic waste from potato starch industries) by Fusarium oxysporum 841 was improved considerably by using fed-batch culture. In this, two types of feed policies were adopted consisting of different substrate concentrations and feeding times. In fed-batch culture, the enzymes tested, namely avicelase, CMCase, cellobiase and xylanase, showed significant improvements over batch fermentations with regard to enzyme titres and productivities. The maximum concentration, yield and productivity of acetic acid were 22.5 g litre{sup -1}, 0.38 g (g {sub strate}){sup -1} and 0.09 g litre{sup -1} h{sup -1}, respectively, and these values for ethanol were 5.7 g litre{sup -1}, 0.1 g (g substrate){sup -1} and 0.03 g litre{sup -1}h{sup -1}, respectively. (author).

  7. Acid hydrolysis of sisal cellulose: studies aiming at nano fibers and bio ethanol preparation

    International Nuclear Information System (INIS)

    Paula, Mauricio P. de; Lacerda, Talita M.; Zambon, Marcia D.; Frollini, Elisabete

    2009-01-01

    The hydrolysis of cellulose can result in nanofibers and also is an important stage in the bioethanol production process. In order to evaluate the influence of acid (sulfuric) concentration, temperature, and native cellulose (sisal) pretreatment on cellulose hydrolysis, the acid concentration was varied between 5% and 30% (v/v) in the temperature range from 60 to 100 deg C using native and alkali-treated (mercerized) sisal cellulose. The following techniques were used to evaluate the residual (non-hydrolysed) cellulose characteristics: viscometry, average degree of polymerization (DP), X-ray diffraction, crystallinity index, and Scanning Electron Microscopy. The sugar cane liquor was analyzed in terms of sugar composition, using High Performance Liquid Chromatography (HPLC). The results showed that increasing the concentration of sulfuric acid and temperature afforded residual cellulose with lower molecular weight and, up to specific acid concentrations, higher crystallinity indexes, when compared to the original cellulose values, and increased the glucose (the bioethanol precursor ) production of the liquor, which was favored for mercerized cellulose. (author)

  8. Impacts of facility size and location decisions on ethanol production cost

    International Nuclear Information System (INIS)

    Kocoloski, Matt; Michael Griffin, W.; Scott Matthews, H.

    2011-01-01

    Cellulosic ethanol has been identified as a promising alternative to fossil fuels to provide energy for the transportation sector. One of the obstacles cellulosic ethanol must overcome in order to contribute to transportation energy demand is the infrastructure required to produce and distribute the fuel. Given a nascent cellulosic ethanol industry, locating cellulosic ethanol refineries and creating the accompanying infrastructure is essentially a greenfield problem that may benefit greatly from quantitative analysis. This study models cellulosic ethanol infrastructure investment using a mixed integer program (MIP) that locates ethanol refineries and connects these refineries to the biomass supplies and ethanol demands in a way that minimizes the total cost. For the single- and multi-state regions examined in this study, larger facilities can decrease ethanol costs by $0.20-0.30 per gallon, and placing these facilities in locations that minimize feedstock and product transportation costs can decrease ethanol costs by up to $0.25 per gallon compared to uninformed placement that could result from influences such as local subsidies to encourage economic development. To best benefit society, policies should allow for incentives that encourage these low-cost production scenarios and avoid politically motivated siting of plants. - Research highlights: → Mixed-integer programming can be used to model ethanol infrastructure investment. → Large cellulosic ethanol facilities can decrease production cost by $0.20/gallon. → Optimized facility placement can save $0.25/gallon.

  9. Ammonia fiber expansion (AFEX) pretreatment, enzymatic hydrolysis, and fermentation on empty palm fruit bunch fiber (EPFBF) for cellulosic ethanol production.

    Science.gov (United States)

    Lau, Ming J; Lau, Ming W; Gunawan, Christa; Dale, Bruce E

    2010-11-01

    Empty palm fruit bunch fiber (EPFBF), a readily available cellulosic biomass from palm processing facilities, is investigated as a potential carbohydrate source for cellulosic ethanol production. This feedstock was pretreated using ammonia fiber expansion (AFEX) and enzymatically hydrolyzed. The best tested AFEX conditions were at 135 °C, 45 min retention time, water to dry biomass loading of 1:1 (weight ratio), and ammonia to dry biomass loading of 1:1 (weight ratio). The particle size of the pretreated biomass was reduced post-AFEX. The optimized enzyme formulation consists of Accellerase (84 μL/g biomass), Multifect Xylanase (31 μL/g biomass), and Multifect Pectinase (24 μL/g biomass). This mixture achieved close to 90% of the total maximum yield within 72 h of enzymatic hydrolysis. Fermentation on the water extract of this biomass affirms that nutrients solely from the pretreated EPFBF can support yeast growth for complete glucose fermentation. These results suggest that AFEX-treated EPFBF can be used for cellulosic biofuels production because biomass recalcitrance has been overcome without reducing the fermentability of the pretreated materials.

  10. Emotional reactivity to incentive downshift as a correlated response to selection of high and low alcohol preferring mice and an influencing factor on ethanol intake.

    Science.gov (United States)

    Matson, Liana M; Grahame, Nicholas J

    2015-11-01

    Losing a job or significant other are examples of incentive loss that result in negative emotional reactions. The occurrence of negative life events is associated with increased drinking (Keyes, Hatzenbuehler, & Hasin, 2011). Further, certain genotypes are more likely to drink alcohol in response to stressful negative life events (Blomeyer et al., 2008; Covault et al., 2007). Shared genetic factors may contribute to alcohol drinking and emotional reactivity, but this relationship is not currently well understood. We used an incentive downshift paradigm to address whether emotional reactivity is elevated in mice predisposed to drink alcohol. We also investigated if ethanol drinking is influenced in High Alcohol Preferring mice that had been exposed to an incentive downshift. Incentive downshift procedures have been widely utilized to model emotional reactivity, and involve shifting a high reward group to a low reward and comparing the shifted group to a consistently rewarded control group. Here, we show that replicate lines of selectively bred High Alcohol Preferring mice exhibited larger successive negative contrast effects than their corresponding replicate Low Alcohol Preferring lines, providing strong evidence for a genetic association between alcohol drinking and susceptibility to the emotional effects of negative contrast. These mice can be used to study the shared neurological and genetic underpinnings of emotional reactivity and alcohol preference. Unexpectedly, an incentive downshift suppressed ethanol drinking immediately following an incentive downshift. This could be due to a specific effect of negative contrast on ethanol consumption or a suppressive effect on consummatory behavior in general. These data suggest that either alcohol intake does not provide the anticipated negative reinforcement, or that a single test was insufficient for animals to learn to drink following incentive downshift. However, the emotional intensity following incentive

  11. A New Proposal Of Cellulosic Ethanol To Boost Sugarcane Biorefineries: Techno-economic Evaluation

    OpenAIRE

    Albarelli J.Q.; Ensinas A.V.; Silva M.A.

    2014-01-01

    Commercial simulator Aspen Plus was used to simulate a biorefinery producing ethanol from sugarcane juice and second generation ethanol production using bagasse fine fraction composed of parenchyma cells (P-fraction). Liquid hot water and steam explosion pretreatment technologies were evaluated. The processes were thermal and water integrated and compared to a biorefinery producing ethanol from juice and sugarcane bagasse. The results indicated that after thermal and water integration, the ev...

  12. A biorefinery concept for simultaneous recovery of cellulosic ethanol and phenolic compounds from oil palm fronds: Process optimization

    International Nuclear Information System (INIS)

    Ofori-Boateng, Cynthia; Lee, Keat Teong; Saad, Bahruddin

    2014-01-01

    Highlights: • Biorefinery concept for simultaneous recovery of cellulose and phenolic compounds. • Sono-assisted organosolv/H 2 O 2 pretreatment was used to isolate palm fronds cellulose. • Optimum conditions for pretreatment: 60 °C, 40 min, 1:20 g/ml, 3% NaOH concentration. • Optimum conditions yielded 55.3% cellulose, 20.1 g/l glucose and 0.769 g/g ethanol. • Pretreatment liquor contained 4.691 mg GAE/g phenolics. - Abstract: In this study, process optimization of an ultrasonic-assisted organosolv/liquid oxidative pretreatment (SOP) of oil palm fronds (OPFs) for the simultaneous recovery of cellulose, bioethanol and biochemicals (i.e. phenolic compounds) in a biorefinery concept was carried out. The effects of time (30–60 min.), temperature (40–80 °C), NaOH concentration (1–5%) and sample:solvent ratio (1:10–1:50 g/ml) on cellulose content, bioethanol yield and total phenolics contents (TPC) after SOP were investigated. At optimum conditions of pretreatment (i.e. 60 °C, 40 min, 3% w/v aq. NaOH and 1:20 g/ml sample to solvent ratio), the recovered cellulose (55.30%) which served as substrate for enzymatic hydrolysis and subsequent fermentation yielded about 20.1 g/l glucose, 11.3 g/l xylose and 9.3 g/l bioethanol (yield of 0.769 g/g). The pretreatment liquor (mostly regarded as wastes) obtained at the optimum pretreatment conditions contained about 4.691 mg gallic acid equivalent (GAE)/g OPFs of TPC, 0.297 mg vanillic acid (VA)/g OPFs, 1.591 mg gallic acid (GA)/g OPFs and 0.331 mg quercetin (QU)/g OPFs. The pretreatment liquor was again analyzed to possess high antiradical scavenging activity (about 97.2%) compared to the synthetic antioxidant, 3,5-di-tert-butyl-4-hydroxytoluene (BHT) (80.7%) at 100 ppm. Thus one sustainable way of managing wastes in biorefinery is the recovery of multi-bioproducts (e.g. bioethanol and biochemicals) during the pretreatment process

  13. Removal of the Fermentation Inhibitor, Furfural, Using Activated Carbon in Cellulosic-Ethanol Production

    KAUST Repository

    Zhang, Kuang

    2011-12-21

    Ethanol can be produced from lignocellulosic biomass through fermentation; however, some byproducts from lignocellulosics, such as furfural compounds, are highly inhibitory to the fermentation and can substantially reduce the efficiency of ethanol production. In this study, commercial and polymer-derived activated carbons were utilized to selectively remove the model fermentation inhibitor, furfural, from water solution during bioethanol production. The oxygen functional groups on the carbon surface were found to influence the selectivity of sorbents between inhibitors and sugars during the separation. After inhibitors were selectively removed from the broth, the cell growth and ethanol production efficiency was recovered noticeably in the fermentation. A sorption/desorption cycle was designed, and the sorbents were regenerated in a fixed-bed column system using ethanol-containing standard solution. Dynamic mass balance was obtained after running four or five cycles, and regeneration results were stable even after twenty cycles. © 2011 American Chemical Society.

  14. Can Hawaii Meet Its Renewable Fuel Target? Case Study of Banagrass-Based Cellulosic Ethanol

    Directory of Open Access Journals (Sweden)

    Chinh Tran

    2016-08-01

    Full Text Available Banagrass is a biomass crop candidate for ethanol production in the State of Hawaii. This study examines: (i whether enough banagrass can be produced to meet Hawaii’s renewable fuel target of 20% highway fuel demand produced with renewable sources by 2020 and (ii at what cost. This study proposes to locate suitable land areas for banagrass production and ethanol processing, focusing on the two largest islands in the state of Hawaii—Hawaii and Maui. The results suggest that the 20% target is not achievable by using all suitable land resources for banagrass production on both Hawaii and Maui. A total of about 74,224,160 gallons, accounting for 16.04% of the state’s highway fuel demand, can be potentially produced at a cost of $6.28/gallon. Lower ethanol cost is found when using a smaller production scale. The lowest cost of $3.31/gallon is found at a production processing capacity of about 9 million gallons per year (MGY, which meets about 2% of state demand. This cost is still higher than the average imported ethanol price of $3/gallon. Sensitivity analysis finds that it is possible to produce banagrass-based ethanol on Hawaii Island at a cost below the average imported ethanol price if banagrass yield increases of at least 35.56%.

  15. Production of liquid transport fuel from cellulose material (wood). III Laboratory preparation of wood sugars and fermentation to ethanol and yeast

    Energy Technology Data Exchange (ETDEWEB)

    Whitworth, D A; Harwood, V D

    1977-10-25

    A laboratory procedure is described for hydrolyzing cellulose material to sugars by the use of hot sulfuric acid. The procedure has been used routinely for assessing raw materials. Raw materials used were radiata pine (fresh wood and decayed thinnings), pine needles, sawdust from old dumps, newspaper, cardboard, beech wood, and coconut wood. The neutralized sugar-liquors produced, supplemented with fertilizer grade nutrients, were fermented with bakers' yeast and gave near optimal conversion of hexoses to ethanol and of pentoses to protein biomass. From 100 g radiata pine (wood: bark mix 85:15) 25 ml (20 g) of ethanol and 2 g yeast biomass were routinely produced, although fermentation rates were lower than with pure sugars. The results, however, clearly showed that, by a hot dilute sulfure acid hydrolysis followed by a yeast fermentation process, cellulose resources avaliable in New Zealand are suitable for conversion to ethanol. 5 table, 1 figure.

  16. Comparison of cellulosic ethanol yields from midwestern maize and reconstructed tallgrass prairie systems managed for bioenergy

    Science.gov (United States)

    Maize- and prairie-based systems were investigated as cellulosic feedstocks by conducting a 9 ha side-by-side comparison on fertile soils in the Midwestern United States. Maize was grown continuously with adequate fertilization over years both with and without a winter rye cover crop, and the 31-spe...

  17. Cellulosic-based ethanol and the contribution from agriculture and forestry

    Science.gov (United States)

    Robert D. Perlack; Bryce J. Stokes; John Ferrell; Mary Bohman; Kenneth E. Skog; Dennis P. Dykstra; Patricia K. Lebow; Patrick D. Miles

    2008-01-01

    The cellulosic feedstocks (see chapter 2) needed to produce 20 billion gallons per year (BGY) of second-generation and other renewable fuels can come from a wide variety of cropland and forestland sources, including imports. The impact of producing these biofuels on U.S. agriculture and forestry will very much depend on the relative proportions of cropland- and...

  18. An oil palm-based biorefinery concept for cellulosic ethanol and phytochemicals production: Sustainability evaluation using exergetic life cycle assessment

    International Nuclear Information System (INIS)

    Ofori-Boateng, Cynthia; Lee, Keat Teong

    2014-01-01

    In this study, thermo-environmental sustainability of an oil palm-based biorefinery concept for the co-production of cellulosic ethanol and phytochemicals from oil palm fronds (OPFs) was evaluated based on exergetic life cycle assessment (ExLCA). For the production of 1 tonne bioethanol, the exergy content of oil palm seeds was upgraded from 236 MJ to 77,999 MJ during the farming process for OPFs production. Again, the high exergy content of the OPFs was degraded by about 62.02% and 98.36% when they were converted into cellulosic ethanol and phenolic compounds respectively. With a total exergy destruction of about 958,606 MJ (internal) and 120,491 MJ (external or exergy of wastes), the biorefinery recorded an overall exergy efficiency and thermodynamic sustainability index (TSI) of about 59.05% and 2.44 per tonne of OPFs' bioethanol respectively. Due to the use of fossil fuels, pesticides, fertilizers and other toxic chemicals during the production, the global warming potential (GWP = 2265.69 kg CO 2 eq.), acidification potential (AP = 355.34 kg SO 2 eq.) and human toxicity potential (HTP = 142.79 kg DCB eq.) were the most significant environmental impact categories for a tonne of bioethanol produced in the biorefinery. The simultaneous saccharification and fermentation (SSF) unit emerged as the most exergetically efficient (89.66%), thermodynamically sustainable (TSI = 9.67) and environmentally friendly (6.59% of total GWP) production system. -- Highlights: • Thermo-environmental sustainability of palm-based biorefinery was assessed. • OPFs' exergy content was degraded when converted into bioethanol and phytochemicals. • Exergy efficiency (59.05%) and TSI (2.44) were recorded for the biorefinery • Global warming potential of 2265.6 kg CO 2 eq. was recorded for the whole biorefinery

  19. A New Proposal of Cellulosic Ethanol to Boost Sugarcane Biorefineries: Techno-Economic Evaluation

    Directory of Open Access Journals (Sweden)

    Juliana Q. Albarelli

    2014-01-01

    Full Text Available Commercial simulator Aspen Plus was used to simulate a biorefinery producing ethanol from sugarcane juice and second generation ethanol production using bagasse fine fraction composed of parenchyma cells (P-fraction. Liquid hot water and steam explosion pretreatment technologies were evaluated. The processes were thermal and water integrated and compared to a biorefinery producing ethanol from juice and sugarcane bagasse. The results indicated that after thermal and water integration, the evaluated processes were self-sufficient in energy demand, being able to sell the surplus electricity to the grid, and presented water intake inside the environmental limit for São Paulo State, Brazil. The processes that evaluated the use of the bagasse fine fraction presented higher economic results compared with the use of the entire bagasse. Even though, due to the high enzyme costs, the payback calculated for the biorefineries were higher than 8 years for all cases that considered second generation ethanol and the net present value for the investment was negative. The reduction on the enzyme load, in a way that the conversion rates could be maintained, is the limiting factor to make second generation ethanol competitive with the most immediate uses of bagasse: fuel for the cogeneration system to surplus electricity production.

  20. Simultaneous co-fermentation of mixed sugars: a promising strategy for producing cellulosic ethanol.

    Science.gov (United States)

    Kim, Soo Rin; Ha, Suk-Jin; Wei, Na; Oh, Eun Joong; Jin, Yong-Su

    2012-05-01

    The lack of microbial strains capable of fermenting all sugars prevalent in plant cell wall hydrolyzates to ethanol is a major challenge. Although naturally existing or engineered microorganisms can ferment mixed sugars (glucose, xylose and galactose) in these hydrolyzates sequentially, the preferential utilization of glucose to non-glucose sugars often results in lower overall yield and productivity of ethanol. Therefore, numerous metabolic engineering approaches have been attempted to construct optimal microorganisms capable of co-fermenting mixed sugars simultaneously. Here, we present recent findings and breakthroughs in engineering yeast for improved ethanol production from mixed sugars. In particular, this review discusses new sugar transporters, various strategies for simultaneous co-fermentation of mixed sugars, and potential applications of co-fermentation for producing fuels and chemicals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Cellulose utilization: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Bassham, J A

    1975-01-01

    To summarize, the conversion of cellulose to ethanol via hydrolysis to glucose followed by fermentation appears to be highly efficient in terms of energy conservation, yield, and quality of product, especially when reasonably high quality cellulosic waste is available.

  2. The greenhouse gas emissions performance of cellulosic ethanol supply chains in Europe

    Directory of Open Access Journals (Sweden)

    Bauen Ausilio

    2009-08-01

    Full Text Available Abstract Background Calculating the greenhouse gas savings that may be attributed to biofuels is problematic because production systems are inherently complex and methods used to quantify savings are subjective. Differing approaches and interpretations have fuelled a debate about the environmental merit of biofuels, and consequently about the level of policy support that can be justified. This paper estimates and compares emissions from plausible supply chains for lignocellulosic ethanol production, exemplified using data specific to the UK and Sweden. The common elements that give rise to the greatest greenhouse gas emissions are identified and the sensitivity of total emissions to variations in these elements is estimated. The implications of including consequential impacts including indirect land-use change, and the effects of selecting alternative allocation methods on the interpretation of results are discussed. Results We find that the most important factors affecting supply chain emissions are the emissions embodied in biomass production, the use of electricity in the conversion process and potentially consequential impacts: indirect land-use change and fertiliser replacement. The large quantity of electricity consumed during enzyme manufacture suggests that enzymatic conversion processes may give rise to greater greenhouse gas emissions than the dilute acid conversion process, even though the dilute acid process has a somewhat lower ethanol yield. Conclusion The lignocellulosic ethanol supply chains considered here all lead to greenhouse gas savings relative to gasoline An important caveat to this is that if lignocellulosic ethanol production uses feedstocks that lead to indirect land-use change, or other significant consequential impacts, the benefit may be greatly reduced. Co-locating ethanol, electricity generation and enzyme production in a single facility may improve performance, particularly if this allows the number of energy

  3. Pilot plant studies of the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1977-01-31

    Progress is reported in several areas of research. The following cellulosic raw materials were selected for study: wheat, barley, and rice straws, rice hulls, sorghum, corn stover, cotton gin trash, newsprint, ground wood, and masonite steam-treated Douglas fir and redwood. Samples were collected, prepared, and analyzed for hexosans, pentosans, lignin, ash, and protein. Results of acid extraction and enzymatic hydrolysis are discussed. Yields of glucose, polyglucose, xylose, and arabinose are reported. Progress in process design and economic studies, as well as pilot plant process development and design studies, is summarized. (JGB)

  4. Process development studies on the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1978-02-01

    Progress is reported on studies on the NO--O/sub 2/ pretreatment of wheat straw prior to enzymatic hydrolysis. Studies of the conversion of xylose to ethanol by Fusarium oxysporum were continued. Progress is also reported on pilot plant process development and design studies on continuous cellulase production, enzyme recovery, batch cellulase enzyme production from Trichoderma viride, and kinetic modelling of the enzymatic hydrolysis of 5 percent newsprint. (JGB)

  5. Pilot plant studies of the bioconversion of cellulose and production of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1977-09-30

    Work for the period July 1 to September 30, 1977 is summarized briefly. Results of the following studies are reported: analysis and evaluation of potential raw materials--chemical analysis of the Kudzu plant and effect of NO/sub x/ pretreatments on the hydrolysis of wheat straw; utilization of hemicellulose sugars; process design and economic studies--hydrolysis process and ethanol fermentation; pilot plant process development and design studies--enhanced cellulase production and continuous hydrolysis. (JGB)

  6. Bioconversion of cellulose to liquid fuel (ethanol). Final report, Stage 2, 1983-06-30

    Energy Technology Data Exchange (ETDEWEB)

    Hahn-Haegerdal, B

    1983-01-01

    The process routes of the conversion have been investigated. The material which contains lignocellulose should be pretreated, and the separate processes are to be integrated. The price of raw materials and enzymes influences the process economy. The efficiency of biocatalysts on fermentation and saccharification are being studied and the reuse of enzymes is discussed. The process for the production of ethanol out of lignocellulose is shown to be very complicated. The optimization of the process will necessitate computerized simulation.

  7. Uncertainty in techno-economic estimates of cellulosic ethanol production due to experimental measurement uncertainty

    Directory of Open Access Journals (Sweden)

    Vicari Kristin J

    2012-04-01

    Full Text Available Abstract Background Cost-effective production of lignocellulosic biofuels remains a major financial and technical challenge at the industrial scale. A critical tool in biofuels process development is the techno-economic (TE model, which calculates biofuel production costs using a process model and an economic model. The process model solves mass and energy balances for each unit, and the economic model estimates capital and operating costs from the process model based on economic assumptions. The process model inputs include experimental data on the feedstock composition and intermediate product yields for each unit. These experimental yield data are calculated from primary measurements. Uncertainty in these primary measurements is propagated to the calculated yields, to the process model, and ultimately to the economic model. Thus, outputs of the TE model have a minimum uncertainty associated with the uncertainty in the primary measurements. Results We calculate the uncertainty in the Minimum Ethanol Selling Price (MESP estimate for lignocellulosic ethanol production via a biochemical conversion process: dilute sulfuric acid pretreatment of corn stover followed by enzymatic hydrolysis and co-fermentation of the resulting sugars to ethanol. We perform a sensitivity analysis on the TE model and identify the feedstock composition and conversion yields from three unit operations (xylose from pretreatment, glucose from enzymatic hydrolysis, and ethanol from fermentation as the most important variables. The uncertainty in the pretreatment xylose yield arises from multiple measurements, whereas the glucose and ethanol yields from enzymatic hydrolysis and fermentation, respectively, are dominated by a single measurement: the fraction of insoluble solids (fIS in the biomass slurries. Conclusions We calculate a $0.15/gal uncertainty in MESP from the TE model due to uncertainties in primary measurements. This result sets a lower bound on the error bars of

  8. A novel marine bacterium Isoptericola sp. JS-C42 with the ability to saccharifying the plant biomasses for the aid in cellulosic ethanol production.

    Science.gov (United States)

    Santhi, Velayudhan Satheeja; Gupta, Ashutosh; Saranya, Somasundaram; Jebakumar, Solomon Robinson David

    2014-06-01

    The ever growing demands for food products such as starch and sugar produces; there is a need to find the sources for saccharification for cellulosic bioethanol production. This study provides the first evidence of the lignocellulolytic and saccharifying ability of a marine bacterium namely Isoptericola sp. JS-C42, a Gram positive actinobacterium with the cocci cells embedded on mycelia isolated from the Arabian Sea, India. It exhibited highest filter paper unit effect, endoglucanase, exoglucanase, cellobiohydrolase, β-glucosidase, xylanase and ligninase effect. The hydrolytic potential of the enzymes displayed the efficient saccharification capability of steam pretreated biomass. It was also found to degrade the paddy, sorghum, Acacia mangium and Ficus religiosa into simple reducing sugars by its efficient lignocellulose enzyme complex with limited consumption of sugars. Production of ethanol was also achieved with the Saccharomyces cerevisiae . Overall, it offers a great potential for the cellulosic ethanol production in an economically reliable and eco-friendly point-of-care.

  9. Fungal enzyme production in seeds of transgenic canola plants for conversion of cellulosic materials to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, K.J.; Beauchemin, K.A. [Agriculture and Agri-Food Canada, Lethbridge, AB (Canada); Moloney, M.M. [Calgary Univ., AB (Canada). Dept. of Biological Sciences

    1997-07-01

    The fuel alcohol industry makes use of industrial enzymes to effectively degrade fibrous plant cell walls. Carbohydrates in cellulosic materials are in the form of complex sugars that can be hydrolyzed to simple sugars by fungal fibrolytic enzymes such as cellulases and xylanases. This study was conducted to find a cost effective way to produce fibrolytic enzymes using gene fusion technology in which a xylanase gene and a cellulase gene from two fungal species are introduced into canola to be a carrier for the production of these enzymes. The two genes had been analyzed for maximal enzymatic activity to minimize side effects. Results of the study demonstrated the stability and potential of transgenic oil-bodies as an immobilized enzyme matrix, and showed that it is possible to express fibrolytic enzymes in canola.

  10. Cellulase and alcohol dehydrogenase immobilized in Langmuir and Langmuir-Blodgett films and their molecular-level effects upon contact with cellulose and ethanol.

    Science.gov (United States)

    Rodrigues, Dilmer; Camilo, Fernanda Ferraz; Caseli, Luciano

    2014-02-25

    The key challenges for producing devices based on nanostructured films with control over the molecular architecture are to preserve the catalytic activity of the immobilized biomolecules and to provide a reliable method for determining the intermolecular interactions and the accommodation of molecules at very small scales. In this work, the enzymes cellulase and alcohol dehydrogenase (ADH) were coimmobilized with dipalmitoylphosphatidylcholine (DPPC) as Langmuir-Blodgett (LB) films, and their biological activities were assayed by accommodating the structure formed in contact with cellulose. For this purpose, the polysaccharide was dissolved in an ionic liquid, 1-buthyl-3-methylimidazolium chloride (BMImCl), and dropped on the top of the hybrid cellulase-ADH-DPPC LB film. The interactions between cellulose and ethanol, which are the catalytic substrates of the enzymes as well as important elements in the production of second-generation fuels, were then investigated using polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS). Investigation of the secondary structures of the enzymes was performed using PM-IRRAS, through which the presence of ethanol and cellulose was observed to highly affect the structures of ADH and cellulase, respectively. The detection of products formed from the catalyzed reactions as well as the changes of secondary structure of the enzymes immobilization could be carried out, which opens the possibility to produce a means for producing second-generation ethanol using nanoscale arrangements.

  11. Separate hydrolysis and fermentation (SHF) of Prosopis juliflora, a woody substrate, for the production of cellulosic ethanol by Saccharomyces cerevisiae and Pichia stipitis-NCIM 3498.

    Science.gov (United States)

    Gupta, Rishi; Sharma, Krishna Kant; Kuhad, Ramesh Chander

    2009-02-01

    Prosopis juliflora (Mesquite) is a raw material for long-term sustainable production of cellulosics ethanol. In this study, we used acid pretreatment, delignification and enzymatic hydrolysis to evaluate the pretreatment to produce more sugar, to be fermented to ethanol. Dilute H(2)SO(4) (3.0%,v/v) treatment resulted in hydrolysis of hemicelluloses from lignocellulosic complex to pentose sugars along with other byproducts such as furfural, hydroxymethyl furfural (HMF), phenolics and acetic acid. The acid pretreated substrate was delignified to the extent of 93.2% by the combined action of sodium sulphite (5.0%,w/v) and sodium chlorite (3.0%,w/v). The remaining cellulosic residue was enzymatically hydrolyzed in 0.05 M citrate phosphate buffer (pH 5.0) using 3.0 U of filter paper cellulase (FPase) and 9.0 U of beta-glucosidase per mL of citrate phosphate buffer. The maximum enzymatic saccharification of cellulosic material (82.8%) was achieved after 28 h incubation at 50 degrees C. The fermentation of both acid and enzymatic hydrolysates, containing 18.24 g/L and 37.47 g/L sugars, with Pichia stipitis and Saccharomyces cerevisiae produced 7.13 g/L and 18.52 g/L of ethanol with corresponding yield of 0.39 g/g and 0.49 g/g, respectively.

  12. Ethanol from Cellulosic Biomass with Emphasis of Wheat Straw Utilization. Analysis of Strategies for Process Development

    Directory of Open Access Journals (Sweden)

    Alexander Dimitrov Kroumov

    2015-12-01

    Full Text Available The "Green and Blue Technologies Strategies in HORIZON 2020" has increased the attention of scientific society on global utilization of renewable energy sources. Agricultural residues can be a valuable source of energy because of drastically growing human needs for food. The goal of this review is to show the current state of art on utilization of wheat straw as a substrate for ethanol production. The specifics of wheat straw composition and the chemical and thermodynamic properties of its components pre-determined the application of unit operations and engineering strategies for hydrolysis of the substrate and further its fermentation. Modeling of this two processes is crucially important for optimal overall process development and scale up. The authors gave much attention on main hydrolisis products as a glucose and xylose (C6 and C5 sugars, respectivelly and on the specifics of their metabolization by ethanol producing microorganisms. The microbial physiology reacting on C6 and C5 sugars and mathematical aproaches describing these phenomena are discussing, as well.

  13. Improved enzymatic saccharification of steam exploded cotton stalk using alkaline extraction and fermentation of cellulosic sugars into ethanol.

    Science.gov (United States)

    Keshav, Praveen K; Naseeruddin, Shaik; Rao, L Venkateswar

    2016-08-01

    Cotton stalk, a widely available and cheap agricultural residue lacking economic alternatives, was subjected to steam explosion in the range 170-200°C for 5min. Steam explosion at 200°C and 5min led to significant hemicellulose solubilization (71.90±0.10%). Alkaline extraction of steam exploded cotton stalk (SECOH) using 3% NaOH at room temperature for 6h led to 85.07±1.43% lignin removal with complete hemicellulose solubilization. Besides, this combined pretreatment allowed a high recovery of the cellulosic fraction from the biomass. Enzymatic saccharification was studied between steam exploded cotton stalk (SECS) and SECOH using different cellulase loadings. SECOH gave a maximum of 785.30±8.28mg/g reducing sugars with saccharification efficiency of 82.13±0.72%. Subsequently, fermentation of SECOH hydrolysate containing sugars (68.20±1.16g/L) with Saccharomyces cerevisiae produced 23.17±0.84g/L ethanol with 0.44g/g yield. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Performance of CSTR-EGSB-SBR system for treating sulfate-rich cellulosic ethanol wastewater and microbial community analysis.

    Science.gov (United States)

    Shan, Lili; Zhang, Zhaohan; Yu, Yanling; Ambuchi, John Justo; Feng, Yujie

    2017-06-01

    Performance and microbial community composition were evaluated in a two-phase anaerobic and aerobic system treating sulfate-rich cellulosic ethanol wastewater (CEW). The system was operated at five different chemical oxygen demand (COD)/SO 4 2- ratios (63.8, 26.3, 17.8, 13.7, and 10.7). Stable performance was obtained for total COD removal efficiency (94.5%), sulfate removal (89.3%), and methane production rate (11.5 L/day) at an organic loading rate of 32.4 kg COD/(m 3 ·day). The acidogenic reactor made a positive contribution to net VFAs production (2318.1 mg/L) and sulfate removal (60.9%). Acidogenic bacteria (Megasphaera, Parabacteroides, unclassified Ruminococcaceae spp., and Prevotella) and sulfate-reducing bacteria (Butyrivibrio, Megasphaera) were rich in the acidogenic reactor. In the methanogenic reactor, high diversity of microorganisms corresponded with a COD removal contribution of 83.2%. Moreover, methanogens (Methanosaeta) were predominant, suggesting that these organisms played an important role in the acetotrophic methanogenesis pathway. The dominant aerobic bacteria (Truepera) appeared to have been responsible for the COD removal of the SBR. These results indicate that dividing the sulfate reduction process could effectively minimize sulfide toxicity, which is important for the successful operation of system treating sulfate-rich CEW.

  15. Thermogravimetric analysis of the behavior of sub-bituminous coal and cellulosic ethanol residue during co-combustion.

    Science.gov (United States)

    Buratti, C; Barbanera, M; Bartocci, P; Fantozzi, F

    2015-06-01

    The influence of the addition of cellulosic ethanol residue (CER) on the combustion of Indonesian sub-bituminous coal was analyzed by non isothermal thermo-gravimetric analysis (TGA). The effect of blends ratio (5%, 10%, 15% and 20%), interaction mechanism, and heating rate (5°C/min, 10°C/min, 15°C/min, 20°C/min) on the combustion process was studied. The results show that the increase of the blending ratio allows to achieve the increase of the combustibility index from 7.49E-08 to 5.26E-07 at the blending ratio of 20%. Two types of non-isothermal kinetic analysis methods (Ozawa-Flynn-Wall and Vyazovkin) were also applied. Results indicate that the activation energy of the blends decreases with increasing the conversion rate. In particular, the blending ratio of 20% confirms to have the better combustion performance, with the average value of the activation energy equal to 41.10 kJ/mol obtained by Ozawa-Flynn-Wall model and 31.17 kJ/mol obtained by Vyazovkin model. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Evaluation of electricity generation from lignin residue and biogas in cellulosic ethanol production.

    Science.gov (United States)

    Liu, Gang; Bao, Jie

    2017-11-01

    This study takes the first insight on the rigorous evaluation of electricity generation based on the experimentally measured higher heating value (HHV) of lignin residue, as well as the chemical oxygen demand (COD) and biological oxygen demand (BOD 5 ) of wastewater. For producing one metric ton of ethanol fuel from five typical lignocellulose substrates, including corn stover, wheat straw, rice straw, sugarcane bagasse and poplar sawdust, 1.26-1.85tons of dry lignin residue is generated from biorefining process and 0.19-0.27tons of biogas is generated from anaerobic digestion of wastewater, equivalent to 4335-5981kWh and 1946-2795kWh of electricity by combustion of the generated lignin residue and biogas, respectively. The electricity generation not only sufficiently meets the electricity needs of process requirement, but also generates more than half of electricity surplus selling to the grid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Valorization of lignin and cellulose in acid-steam-exploded corn stover by a moderate alkaline ethanol post-treatment based on an integrated biorefinery concept.

    Science.gov (United States)

    Yang, Sheng; Zhang, Yue; Yue, Wen; Wang, Wei; Wang, Yun-Yan; Yuan, Tong-Qi; Sun, Run-Cang

    2016-01-01

    Due to the unsustainable consumption of fossil resources, great efforts have been made to convert lignocellulose into bioethanol and commodity organic compounds through biological methods. The conversion of cellulose is impeded by the compactness of plant cell wall matrix and crystalline structure of the native cellulose. Therefore, appropriate pretreatment and even post-treatment are indispensable to overcome this problem. Additionally, an adequate utilization of coproduct lignin will be important for improving the economic viability of modern biorefinery industries. The effectiveness of moderate alkaline ethanol post-treatment on the bioconversion efficiency of cellulose in the acid-steam-exploded corn stover was investigated in this study. Results showed that an increase of the alcoholic sodium hydroxide (NaOH) concentration from 0.05 to 4% led to a decrease in the lignin content in the post-treated samples from 32.8 to 10.7%, while the cellulose digestibility consequently increased. The cellulose conversion of the 4% alcoholic NaOH integrally treated corn stover reached up to 99.3% after 72 h, which was significantly higher than that of the acid steam exploded corn stover without post-treatment (57.3%). In addition to the decrease in lignin content, an expansion of cellulose I lattice induced by the 4% alcoholic NaOH post-treatment played a significant role in promoting the enzymatic hydrolysis of corn stover. More importantly, the lignin fraction (AL) released during the 4% alcoholic NaOH post-treatment and the lignin-rich residue (EHR) remained after the enzymatic hydrolysis of the 4% alcoholic NaOH post-treated acid-steam-exploded corn stover were employed to synthesize lignin-phenol-formaldehyde (LPF) resins. The plywoods prepared with the resins exhibit satisfactory performances. An alkaline ethanol system with an appropriate NaOH concentration could improve the removal of lignin and modification of the crystalline structure of cellulose in acid

  18. Cellulosic ethanol: interactions between cultivar and enzyme loading in wheat straw processing

    Directory of Open Access Journals (Sweden)

    Felby Claus

    2010-11-01

    Full Text Available Abstract Background Variations in sugar yield due to genotypic qualities of feedstock are largely undescribed for pilot-scale ethanol processing. Our objectives were to compare glucose and xylose yield (conversion and total sugar yield from straw of five winter wheat cultivars at three enzyme loadings (2.5, 5 and 10 FPU g-1 dm pretreated straw and to compare particle size distribution of cultivars after pilot-scale hydrothermal pretreatment. Results Significant interactions between enzyme loading and cultivars show that breeding for cultivars with high sugar yields under modest enzyme loading could be warranted. At an enzyme loading of 5 FPU g-1 dm pretreated straw, a significant difference in sugar yields of 17% was found between the highest and lowest yielding cultivars. Sugar yield from separately hydrolyzed particle-size fractions of each cultivar showed that finer particles had 11% to 21% higher yields than coarse particles. The amount of coarse particles from the cultivar with lowest sugar yield was negatively correlated with sugar conversion. Conclusions We conclude that genetic differences in sugar yield and response to enzyme loading exist for wheat straw at pilot scale, depending on differences in removal of hemicellulose, accumulation of ash and particle-size distribution introduced by the pretreatment.

  19. Economic and environmental assessment of cellulosic ethanol production scenarios annexed to a typical sugar mill.

    Science.gov (United States)

    Ali Mandegari, Mohsen; Farzad, Somayeh; Görgens, Johann F

    2017-01-01

    In this work different biorefinery scenarios were investigated, concerning the co-production of bioethanol and electricity from available lignocellulose at a typical sugar mill, as possible extensions to the current combustion of bagasse for steam and electricity production and burning trash on-filed. In scenario 1, the whole bagasse and brown leaves is utilized in a biorefinery and coal is burnt in the existing inefficient sugar mill boiler. Scenario 2 & 3 are assumed with a new centralized CHP unit without/with coal co-combustion, respectively. Also, through scenarios 4 & 5, the effect of water insoluble loading were studied. All scenarios provided energy for the sugarmill and the ethanol plant, with the export of surplus electricity. Economic analysis determined that scenario 1 was the most viable scenario due to less capital cost and economies-of scale. Based on Life Cycle Assessment (LCA) results, scenario 2 outperformed the other scenarios, while three scenarios showed lower contribution to environmental burdens than the current situation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Evaluation of Ethanol Production Activity by Engineered Saccharomyces cerevisiae Fermenting Cellobiose through the Phosphorolytic Pathway in Simultaneous Saccharification and Fermentation of Cellulose.

    Science.gov (United States)

    Lee, Won-Heong; Jin, Yong-Su

    2017-09-28

    In simultaneous saccharification and fermentation (SSF) for production of cellulosic biofuels, engineered Saccharomyces cerevisiae capable of fermenting cellobiose has provided several benefits, such as lower enzyme costs and faster fermentation rate compared with wild-type S. cerevisiae fermenting glucose. In this study, the effects of an alternative intracellular cellobiose utilization pathway-a phosphorolytic pathway based on a mutant cellodextrin transporter (CDT-1 (F213L)) and cellobiose phosphorylase (SdCBP)-was investigated by comparing with a hydrolytic pathway based on the same transporter and an intracellular β-glucosidase (GH1-1) for their SSF performances under various conditions. Whereas the phosphorolytic and hydrolytic cellobiose-fermenting S. cerevisiae strains performed similarly under the anoxic SSF conditions, the hydrolytic S. cerevisiae performed slightly better than the phosphorolytic S. cerevisiae under the microaerobic SSF conditions. Nonetheless, the phosphorolytic S. cerevisiae expressing the mutant CDT-1 showed better ethanol production than the glucose-fermenting S. cerevisiae with an extracellular β-glucosidase, regardless of SSF conditions. These results clearly prove that introduction of the intracellular cellobiose metabolic pathway into yeast can be effective on cellulosic ethanol production in SSF. They also demonstrate that enhancement of cellobiose transport activity in engineered yeast is the most important factor affecting the efficiency of SSF of cellulose.

  1. Development of an alcohol dehydrogenase biosensor for ethanol determination with toluidine blue O covalently attached to a cellulose acetate modified electrode.

    Science.gov (United States)

    Alpat, Senol; Telefoncu, Azmi

    2010-01-01

    In this work, a novel voltammetric ethanol biosensor was constructed using alcohol dehydrogenase (ADH). Firstly, alcohol dehydrogenase was immobilized on the surface of a glassy carbon electrode modified by cellulose acetate (CA) bonded to toluidine blue O (TBO). Secondly, the surface was covered by a glutaraldehyde/bovine serum albumin (BSA) cross-linking procedure to provide a new voltammetric sensor for the ethanol determination. In order to fabricate the biosensor, a new electrode matrix containing insoluble Toluidine Blue O (TBO) was obtained from the process, and enzyme/coenzyme was combined on the biosensor surface. The influence of various experimental conditions was examined for the characterization of the optimum analytical performance. The developed biosensor exhibited sensitive and selective determination of ethanol and showed a linear response between 1 × 10(-5) M and 4 × 10(-4) M ethanol. A detection limit calculated as three times the signal-to-noise ratio was 5.0 × 10(-6) M. At the end of the 20(th) day, the biosensor still retained 50% of its initial activity.

  2. Development of an Alcohol Dehydrogenase Biosensor for Ethanol Determination with Toluidine Blue O Covalently Attached to a Cellulose Acetate Modified Electrode

    Directory of Open Access Journals (Sweden)

    Azmi Telefoncu

    2010-01-01

    Full Text Available In this work, a novel voltammetric ethanol biosensor was constructed using alcohol dehydrogenase (ADH. Firstly, alcohol dehydrogenase was immobilized on the surface of a glassy carbon electrode modified by cellulose acetate (CA bonded to toluidine blue O (TBO. Secondly, the surface was covered by a glutaraldehyde/bovine serum albumin (BSA cross-linking procedure to provide a new voltammetric sensor for the ethanol determination. In order to fabricate the biosensor, a new electrode matrix containing insoluble Toluidine Blue O (TBO was obtained from the process, and enzyme/coenzyme was combined on the biosensor surface. The influence of various experimental conditions was examined for the characterization of the optimum analytical performance. The developed biosensor exhibited sensitive and selective determination of ethanol and showed a linear response between 1 × 10−5 M and 4 × 10−4 M ethanol. A detection limit calculated as three times the signal-to-noise ratio was 5.0 × 10−6 M. At the end of the 20th day, the biosensor still retained 50% of its initial activity.

  3. A novel marine bacterium Isoptericola sp. JS-C42 with the ability to saccharifying the plant biomasses for the aid in cellulosic ethanol production

    Directory of Open Access Journals (Sweden)

    Velayudhan Satheeja Santhi

    2014-06-01

    Full Text Available The ever growing demands for food products such as starch and sugar produces; there is a need to find the sources for saccharification for cellulosic bioethanol production. This study provides the first evidence of the lignocellulolytic and saccharifying ability of a marine bacterium namely Isoptericola sp. JS-C42, a Gram positive actinobacterium with the cocci cells embedded on mycelia isolated from the Arabian Sea, India. It exhibited highest filter paper unit effect, endoglucanase, exoglucanase, cellobiohydrolase, β-glucosidase, xylanase and ligninase effect. The hydrolytic potential of the enzymes displayed the efficient saccharification capability of steam pretreated biomass. It was also found to degrade the paddy, sorghum, Acacia mangium and Ficus religiosa into simple reducing sugars by its efficient lignocellulose enzyme complex with limited consumption of sugars. Production of ethanol was also achieved with the Saccharomyces cerevisiae. Overall, it offers a great potential for the cellulosic ethanol production in an economically reliable and eco-friendly point-of-care.

  4. High polymorphism in Est-SSR loci for cellulose synthase and β-amylase of sugarcane varieties (Saccharum spp.) used by the industrial sector for ethanol production.

    Science.gov (United States)

    Augusto, Raphael; Maranho, Rone Charles; Mangolin, Claudete Aparecida; Pires da Silva Machado, Maria de Fátima

    2015-01-01

    High and low polymorphisms in simple sequence repeats of expressed sequence tag (EST-SSR) for specific proteins and enzymes, such as β-amylase, cellulose synthase, xyloglucan endotransglucosylase, fructose 1,6-bisphosphate aldolase, and fructose 1,6-bisphosphatase, were used to illustrate the genetic divergence within and between varieties of sugarcane (Saccharum spp.) and to guide the technological paths to optimize ethanol production from lignocellulose biomass. The varieties RB72454, RB867515, RB92579, and SP813250 on the second stage of cutting, all grown in the state of Paraná (PR), and the varieties RB92579 and SP813250 cultured in the PR state and in Northeastern Brazil, state of Pernambuco (PE), were analyzed using five EST-SSR primers for EstC66, EstC67, EstC68, EstC69, and EstC91 loci. Genetic divergence was evident in the EstC67 and EstC69 loci for β-amylase and cellulose synthase, respectively, among the four sugarcane varieties. An extremely high level of genetic differentiation was also detected in the EstC67 locus from the RB82579 and SP813250 varieties cultured in the PR and PE states. High polymorphism in SSR of the cellulose synthase locus may explain the high variability of substrates used in pretreatment and enzymatic hydrolysis processes, which has been an obstacle to effective industrial adaptations.

  5. Energy and greenhouse gas emission effects of corn and cellulosic ethanol with technology improvements and land use changes

    International Nuclear Information System (INIS)

    Wang, Michael Q.; Han, Jeongwoo; Haq, Zia; Tyner, Wallace E.; Wu, May; Elgowainy, Amgad

    2011-01-01

    Use of ethanol as a transportation fuel in the United States has grown from 76 dam 3 in 1980 to over 40.1 hm 3 in 2009 - and virtually all of it has been produced from corn. It has been debated whether using corn ethanol results in any energy and greenhouse gas benefits. This issue has been especially critical in the past several years, when indirect effects, such as indirect land use changes, associated with U.S. corn ethanol production are considered in evaluation. In the past three years, modeling of direct and indirect land use changes related to the production of corn ethanol has advanced significantly. Meanwhile, technology improvements in key stages of the ethanol life cycle (such as corn farming and ethanol production) have been made. With updated simulation results of direct and indirect land use changes and observed technology improvements in the past several years, we conducted a life-cycle analysis of ethanol and show that at present and in the near future, using corn ethanol reduces greenhouse gas emission by more than 20%, relative to those of petroleum gasoline. On the other hand, second-generation ethanol could achieve much higher reductions in greenhouse gas emissions. In a broader sense, sound evaluation of U.S. biofuel policies should account for both unanticipated consequences and technology potentials. We maintain that the usefulness of such evaluations is to provide insight into how to prevent unanticipated consequences and how to promote efficient technologies with policy intervention.

  6. Mapping grasslands suitable for cellulosic biofuels in the Greater Platte River Basin, United States

    Science.gov (United States)

    Wylie, Bruce K.; Gu, Yingxin

    2012-01-01

    Biofuels are an important component in the development of alternative energy supplies, which is needed to achieve national energy independence and security in the United States. The most common biofuel product today in the United States is corn-based ethanol; however, its development is limited because of concerns about global food shortages, livestock and food price increases, and water demand increases for irrigation and ethanol production. Corn-based ethanol also potentially contributes to soil erosion, and pesticides and fertilizers affect water quality. Studies indicate that future potential production of cellulosic ethanol is likely to be much greater than grain- or starch-based ethanol. As a result, economics and policy incentives could, in the near future, encourage expansion of cellulosic biofuels production from grasses, forest woody biomass, and agricultural and municipal wastes. If production expands, cultivation of cellulosic feedstock crops, such as switchgrass (Panicum virgatum L.) and miscanthus (Miscanthus species), is expected to increase dramatically. The main objective of this study is to identify grasslands in the Great Plains that are potentially suitable for cellulosic feedstock (such as switchgrass) production. Producing ethanol from noncropland holdings (such as grassland) will minimize the effects of biofuel developments on global food supplies. Our pilot study area is the Greater Platte River Basin, which includes a broad range of plant productivity from semiarid grasslands in the west to the fertile corn belt in the east. The Greater Platte River Basin was the subject of related U.S. Geological Survey (USGS) integrated research projects.

  7. Ethanol production from residual wood chips of cellulose industry: acid pretreatment investigation, hemicellulosic hydrolysate fermentation, and remaining solid fraction fermentation by SSF process.

    Science.gov (United States)

    Silva, Neumara Luci Conceição; Betancur, Gabriel Jaime Vargas; Vasquez, Mariana Peñuela; Gomes, Edelvio de Barros; Pereira, Nei

    2011-04-01

    Current research indicates the ethanol fuel production from lignocellulosic materials, such as residual wood chips from the cellulose industry, as new emerging technology. This work aimed at evaluating the ethanol production from hemicellulose of eucalyptus chips by diluted acid pretreatment and the subsequent fermentation of the generated hydrolysate by a flocculating strain of Pichia stipitis. The remaining solid fraction generated after pretreatment was subjected to enzymatic hydrolysis, which was carried out simultaneously with glucose fermentation [saccharification and fermentation (SSF) process] using a strain of Saccharomyces cerevisiae. The acid pretreatment was evaluated using a central composite design for sulfuric acid concentration (1.0-4.0 v/v) and solid to liquid ratio (1:2-1:4, grams to milliliter) as independent variables. A maximum xylose concentration of 50 g/L was obtained in the hemicellulosic hydrolysate. The fermentation of hemicellulosic hydrolysate and the SSF process were performed in bioreactors and the final ethanol concentrations of 15.3 g/L and 28.7 g/L were obtained, respectively.

  8. Influence of spatially dependent, modeled soil carbon emission factors on life-cycle greenhouse gas emissions of corn and cellulosic ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Zhangcai [Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue Argonne IL 60439 USA; Dunn, Jennifer B. [Energy Systems Division, Argonne National Laboratory, 9700 South Cass Avenue Argonne IL 60439 USA; Kwon, Hoyoung [Environment and Production Technology Division, International Food Policy Research Institute, 2033 K St. NW Washington DC 20006 USA; Mueller, Steffen [Energy Resources Center, University of Illinois at Chicago, 1309 South Halsted Street Chicago IL 60607 USA; Wander, Michelle M. [Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue Urbana IL 61801 USA

    2016-03-03

    Converting land to biofuel feedstock production incurs changes in soil organic carbon (SOC) that can influence biofuel life-cycle greenhouse gas (GHG) emissions. Estimates of these land use change (LUC) and life-cycle GHG emissions affect biofuels’ attractiveness and eligibility under a number of renewable fuel policies in the U.S. and abroad. Modeling was used to refine the spatial resolution and depth-extent of domestic estimates of SOC change for land (cropland, cropland pasture, grasslands, and forests) conversion scenarios to biofuel crops (corn, corn stover, switchgrass, Miscanthus, poplar, and willow). In most regions, conversions from cropland and cropland pasture to biofuel crops led to neutral or small levels of SOC sequestration, while conversion of grassland and forest generally caused net SOC loss. Results of SOC change were incorporated into the Greenhouse Gases, Regulated Emissions, and Energy use in Transportation (GREET) model to assess their influence on life-cycle GHG emissions for the biofuels considered. Total LUC GHG emissions (g CO2eq MJ-1) were 2.1–9.3 for corn, -0.7 for corn stover, -3.4–12.9 for switchgrass, and -20.1–-6.2 for Miscanthus; these varied with SOC modeling assumptions applied. Extending soil depth from 30 to 100cm affected spatially-explicit SOC change and overall LUC GHG emissions; however the influence on LUC GHG emissions estimates were less significant in corn and corn stover than cellulosic feedstocks. Total life-cycle GHG emissions (g CO2eq MJ-1, 100cm) were estimated to be 59–66 for corn ethanol, 14 for stover ethanol, 18-26 for switchgrass ethanol, and -0.6–-7 for Miscanthus ethanol.

  9. Process development studies on the bioconversion of cellulose and production of ethanol. Progress report, September 1, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1978-09-01

    Progress is reported in studies on the pretreatment of cellulosic materials to facilitate enzymatic hydrolysis, sulfuric acid hydrolysis, investigation of the Purdue processing scheme including an economic analysis, and the fermentability of the enzymatic hydrolyzate. Progress is also reported on enzyme fermentation studies, hydrolysis reactor development, and utilization of hemicellulose sugars. (JSR)

  10. On the conflicting findings of Role of Cellulose-Crystallinity in Enzume Hydrolysis of Biomass

    Science.gov (United States)

    Umesh Agarwal; Sally Ralph

    2014-01-01

    In the field of conversion of biomass to ethanol, an important area of research is the enzymatic hydrolysis of cellulose. Once cellulose is converted to glucose, it can be easily fermented to ethanol. As the cellulosic ethanol technology stands now, costly pretreatments and high dosages of cellulases are needed to achieve complete hydrolysis of the cellulose fraction...

  11. 稀碱预处理棕榈残渣制备纤维乙醇%Pretreatment of oil palm residues by dilute alkali for cellulosic ethanol production

    Institute of Scientific and Technical Information of China (English)

    张海燕; 周玉杰; 李晋平; 戴玲妹; 刘德华; 张建安; Yuen May Choo; Soh Kheang Loh

    2013-01-01

    In the study, we used oil palm residues (empty fruit bunch, EFB) as raw material to produce cellulosic ethanol by pretreatment, enzymatic hydrolysis and fermentation. Firstly, the pretreatment of EFB with alkali, alkali/hydrogen peroxide and the effects on the components and enzymatic hydrolysis of cellulose were studied. The results show that dilute alkali was the suitable pretreatment method and the conditions were first to soak the substrate with 1% sodium hydroxide with a solid-liquid ratio of 1:10 at 40 ℃ for 24 h, and then subjected to 121 ℃ for 30 min. Under the conditions, EFB solid recovery was 74.09%, and glucan, xylan and lignin content were 44.08%, 25.74% and 13.89%, respectively. After separated with alkali solution, the pretreated EFB was washed and hydrolyzed for 72 h with 5% substrate concentration and 30 FPU/g dry mass (DM) enzyme loading, and the conversion of glucan and xylan reached 84.44% and 89.28%, respectively. We further investigated the effects of substrate concentration and enzyme loading on enzymatic hydrolysis and ethanol batch simultaneous saccharification and fermentation (SSF). The results show that when enzyme loading was 30 FPU/g DM and substrate concentration was increased from 5% to 25%, ethanol concentration were 9.76 g/L and 35.25 g/L after 72 h fermentation with Saccharomyces cerevisiae (inoculum size 5%, V/V), which was 79.09% and 56.96% of ethanol theory yield.%以棕榈残渣(Empty fruit bunch,EFB)为原料,通过预处理、酶解、发酵等过程制备纤维乙醇.首先对比了碱、碱/过氧化氢等预处理条件对棕榈残渣组成及酶解的影响,结果表明稀碱预处理效果较好.适宜的稀碱预处理条件为:NaOH浓度为1%,固液比为1∶10,在40℃浸泡24 h后于121℃下保温30 min,在该条件下,EFB的固体回收率为74.09%,纤维素、半纤维素和木质素的含量分别为44.08%、25.74%和13.89%.对该条件下预处理后的固体样品,以底物浓度5

  12. Techno-economic and environmental aspects of the production of medium scale ligno-cellulosic ethanol under Egyptian conditions

    Directory of Open Access Journals (Sweden)

    Shadia R. Tewfik

    2015-12-01

    Full Text Available As a result of actual pilot experimental data and guided by international and national reported estimates, this techno-economic study on a 20,000 ton/y ethanol production plant from rice straw has been conducted. The process essentially comprises preparation of the raw materials, alkaline pretreatment, simultaneous saccharification and fermentation (SSF and dehydration. For the proposed capacity, costs have been estimated based on published information for the equipment as updated to 2013. Operating costs have been estimated according to experimental results of the research team and published information. Financial and sensitivity analyses have been conducted for optimistic and pessimistic scenarios for investment and operating costs and varying sales price of ethanol in the range $0.76/kg–$0.84/kg. Results indicate that positive present values have been obtained at the prevailing discount rate of 3%. The Internal Rate of Return (IRR exceeds the discount rate considerably for the optimistic assumptions and is rather marginal for the pessimistic scenarios. In general, the process is considered technically and economically viable.

  13. Industrial-scale steam explosion pretreatment of sugarcane straw for enzymatic hydrolysis of cellulose for production of second generation ethanol and value-added products.

    Science.gov (United States)

    Oliveira, Fernando M V; Pinheiro, Irapuan O; Souto-Maior, Ana M; Martin, Carlos; Gonçalves, Adilson R; Rocha, George J M

    2013-02-01

    Steam explosion at 180, 190 and 200°C for 15min was applied to sugarcane straw in an industrial sugar/ethanol reactor (2.5m(3)). The pretreated straw was delignificated by sodium hydroxide and hydrolyzed with cellulases, or submitted directly to enzymatic hydrolysis after the pretreatment. The pretreatments led to remarkable hemicellulose solubilization, with the maximum (92.7%) for pretreatment performed at 200°C. Alkaline treatment of the pretreated materials led to lignin solubilization of 86.7% at 180°C, and only to 81.3% in the material pretreated at 200°C. All pretreatment conditions led to high hydrolysis conversion of cellulose, with the maximum (80.0%) achieved at 200°C. Delignification increase the enzymatic conversion (from 58.8% in the cellulignin to 85.1% in the delignificated pulp) of the material pretreated at 180°C, but for the material pretreated at 190°C, the improvement was less remarkable, while for the pretreated at 200°C the hydrolysis conversion decreased after the alkaline treatment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Recycling cellulases for cellulosic ethanol production at industrial relevant conditions: potential and temperature dependency at high solid processes.

    Science.gov (United States)

    Lindedam, Jane; Haven, Mai Østergaard; Chylenski, Piotr; Jørgensen, Henning; Felby, Claus

    2013-11-01

    Different versions of two commercial cellulases were tested for their recyclability of enzymatic activity at high dry matter processes (12% or 25% DM). Recyclability was assessed by measuring remaining enzyme activity in fermentation broth and the ability of enzymes to hydrolyse fresh, pretreated wheat straw. Industrial conditions were used to study the impact of hydrolysis temperature (40 or 50°C) and residence time on recyclability. Enzyme recycling at 12% DM indicated that hydrolysis at 50°C, though ideal for ethanol yield, should be kept short or carried out at lower temperature to preserve enzymatic activity. Best results for enzyme recycling at 25% DM was 59% and 41% of original enzyme load for a Celluclast:Novozyme188 mixture and a modern cellulase preparation, respectively. However, issues with stability of enzymes and their strong adsorption to residual solids still pose a challenge for applicable methods in enzyme recycling. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A case study of agricultural residue availability and cost for a cellulosic ethanol conversion facility in the Henan province of China

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Erin [ORNL; Wu, Yun [ORNL

    2012-05-01

    A preliminary analysis of the availability and cost of corn stover and wheat straw for the area surrounding a demonstration biorefinery in the Henan Province of China was performed as a case study of potential cooperative analyses of bioenergy feedstocks between researchers and industry in the US and China. Though limited in scope, the purpose of this analysis is to provide insight into some of the issues and challenges of estimating feedstock availability in China and how this relates to analyses of feedstocks in the U.S. Completing this analysis also highlighted the importance of improving communication between U.S. researchers and Chinese collaborators. Understanding the units and terms used in the data provided by Tianguan proved to be a significant challenge. This was further complicated by language barriers between collaborators in the U.S. and China. The Tianguan demonstration biorefinery has a current capacity of 3k tons (1 million gallons) of cellulosic ethanol per year with plans to scale up to 10k tons (3.34 million gallons) per year. Using data provided by Tianguan staff in summer of 2011, the costs and availability of corn stover and wheat straw were estimated. Currently, there are sufficient volumes of wheat straw and corn stover that are considered 'waste' and would likely be available for bioenergy in the 20-km (12-mile) region surrounding the demonstration biorefinery at a low cost. However, as the industry grows, competition for feedstock will grow and prices are likely to rise as producers demand additional compensation to fully recover costs.

  16. Fuel ethanol discussion paper

    International Nuclear Information System (INIS)

    1992-01-01

    In recognition of the potential benefits of ethanol and the merits of encouraging value-added agricultural development, a committee was formed to develop options for the role of the Ontario Ministry of Agriculture and Food in the further development of the ethanol industry in Ontario. A consultation with interested parties produced a discussion paper which begins with an outline of the role of ethanol as an alternative fuel. Ethanol issues which require industry consideration are presented, including the function of ethanol as a gasoline oxygenate or octane enhancer, environmental impacts, energy impacts, agricultural impacts, trade and fiscal implications, and regulation. The ethanol industry and distribution systems in Ontario are then described. The current industry consists of one ethanol plant and over 30 retail stations. The key issue for expanding the industry is the economics of producing ethanol. At present, production of ethanol in the short term depends on tax incentives amounting to 23.2 cents/l. In the longer term, a significant reduction in feedstock costs and a significant improvement in processing technology, or equally significant gasoline price increases, will be needed to create a sustainable ethanol industry that does not need incentives. Possible roles for the Ministry are identified, such as support for ethanol research and development, financial support for construction of ethanol plants, and active encouragement of market demand for ethanol-blended gasolines

  17. Opportunity for profitable investments in cellulosic biofuels

    International Nuclear Information System (INIS)

    Babcock, Bruce A.; Marette, Stephan; Treguer, David

    2011-01-01

    Research efforts to allow large-scale conversion of cellulose into biofuels are being undertaken in the US and EU. These efforts are designed to increase logistic and conversion efficiencies, enhancing the economic competitiveness of cellulosic biofuels. However, not enough attention has been paid to the future market conditions for cellulosic biofuels, which will determine whether the necessary private investment will be available to allow a cellulosic biofuels industry to emerge. We examine the future market for cellulosic biofuels, differentiating between cellulosic ethanol and 'drop-in' cellulosic biofuels that can be transported with petroleum fuels and have equivalent energy values. We show that emergence of a cellulosic ethanol industry is unlikely without costly government subsidies, in part because of strong competition from conventional ethanol and limits on ethanol blending. If production costs of drop-in cellulosic biofuels fall enough to become competitive, then their expansion will not necessarily cause feedstock prices to rise. As long as local supplies of feedstocks that have no or low-valued alternative uses exist, then expansion will not cause prices to rise significantly. If cellulosic feedstocks come from dedicated biomass crops, then the supply curves will have a steeper slope because of competition for land. (author)

  18. Incentive Compatibility

    OpenAIRE

    Ledyard, John O.

    1987-01-01

    Incentive compatibility is described and discussed. A summary of the current state of understanding is provided. Key words are: incentive compatibility, game theory, implementation, mechanism, Bayes, Nash, and revelation.

  19. Valorization of lignin and cellulose in acid-steam-exploded corn stover by a moderate alkaline ethanol post-treatment based on an integrated biorefinery concept

    OpenAIRE

    Yang, Sheng; Zhang, Yue; Yue, Wen; Wang, Wei; Wang, Yun-Yan; Yuan, Tong-Qi; Sun, Run-Cang

    2016-01-01

    Background Due to the unsustainable consumption of fossil resources, great efforts have been made to convert lignocellulose into bioethanol and commodity organic compounds through biological methods. The conversion of cellulose is impeded by the compactness of plant cell wall matrix and crystalline structure of the native cellulose. Therefore, appropriate pretreatment and even post-treatment are indispensable to overcome this problem. Additionally, an adequate utilization of coproduct lignin ...

  20. Ethanol production in China: Potential and technologies

    International Nuclear Information System (INIS)

    Li, Shi-Zhong; Chan-Halbrendt, Catherine

    2009-01-01

    Rising oil demand in China has resulted in surging oil imports and mounting environmental pollution. It is projected that by 2030 the demand for fossil fuel oil will be 250 million tons. Ethanol seems to be an attractive renewable alternative to fossil fuel. This study assesses China's ethanol supply potential by examining potential non-food crops as feedstock; emerging conversion technologies; and cost competitiveness. Results of this study show that sweet sorghum among all the non-food feedstocks has the greatest potential. It grows well on the available marginal lands and the ASSF technology when commercialized will shorten the fermentation time which will lower the costs. Other emerging technologies such as improved saccharification and fermentation; and cellulosic technologies will make China more competitive in ethanol production in the future. Based on the estimated available marginal lands for energy crop production and conversion yields of the potential feedstocks, the most likely and optimistic production levels are 19 and 50 million tons of ethanol by 2020. In order to achieve those levels, the roadmap for China is to: select the non-food feedstock most suitable to grow on the available marginal land; provide funding to support the high priority conversion technologies identified by the scientists; provide monetary incentives to new and poor farmers to grow the feedstocks to revitalize rural economy; less market regulation and gradual reduction of subsidies to producers for industry efficiency; and educate consumers on the impact of fossil fuel on the environment to reduce consumption. Since the share of ethanol in the overall fuel demand is small, the impact of ethanol on lowering pollution and enhancing fuel security will be minimal. (author)

  1. Integrated Process for Extraction of Wax as a Value-Added Co-Product and Improved Ethanol Production by Converting Both Starch and Cellulosic Components in Sorghum Grains

    Directory of Open Access Journals (Sweden)

    Nhuan P. Nghiem

    2018-02-01

    Full Text Available Grain sorghum is a potential feedstock for fuel ethanol production due to its high starch content, which is equivalent to that of corn, and has been successfully used in several commercial corn ethanol plants in the United States. Some sorghum grain varieties contain significant levels of surface wax, which may interact with enzymes and make them less efficient toward starch hydrolysis. On the other hand, wax can be recovered as a valuable co-product and as such may help improve the overall process economics. Sorghum grains also contain lignocellulosic materials in the hulls, which can be converted to additional ethanol. An integrated process was developed, consisting of the following steps: 1. Extraction of wax with boiling ethanol, which is the final product of the proposed process; 2. Pretreatment of the dewaxed grains with dilute sulfuric acid; 3. Mashing and fermenting of the pretreated grains to produce ethanol. During the fermentation, commercial cellulase was also added to release fermentable sugars from the hulls, which then were converted to additional ethanol. The advantages of the developed process were illustrated with the following results: (1 Wax extracted (determined by weight loss: ~0.3 wt % of total mass. (2 Final ethanol concentration at 25 wt % solid using raw grains: 86.1 g/L. (3 Final ethanol concentration at 25 wt % solid using dewaxed grains: 106.2 g/L (23.3% improvement. (4 Final ethanol concentration at 25 wt % solid using dewaxed and acid-treated grains (1 wt % H2SO4 plus cellulase (CTec2: 117.8 g/L (36.8% improvement.

  2. High-Octane Mid-Level Ethanol Blend Market Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Caley [National Renewable Energy Lab. (NREL), Golden, CO (United States); Newes, Emily [National Renewable Energy Lab. (NREL), Golden, CO (United States); Brooker, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); McCormick, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Peterson, Steve [Lexidyne, LLC, Colorado Springs, CO (United States); Leiby, Paul [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Martinez, Rocio Uria [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Oladosu, Gbadebo [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brown, Maxwell L. [Colorado School of Mines, Golden, CO (United States)

    2015-12-01

    The United States government has been promoting increased use of biofuels, including ethanol from non-food feedstocks, through policies contained in the Energy Independence and Security Act of 2007. The objective is to enhance energy security, reduce greenhouse gas (GHG) emissions, and provide economic benefits. However, the United States has reached the ethanol blend wall, where more ethanol is produced domestically than can be blended into standard gasoline. Nearly all ethanol is blended at 10 volume percent (vol%) in gasoline. At the same time, the introduction of more stringent standards for fuel economy and GHG tailpipe emissions is driving research to increase the efficiency of spark ignition (SI) engines. Advanced strategies for increasing SI engine efficiency are enabled by higher octane number (more highly knock-resistant) fuels. Ethanol has a research octane number (RON) of 109, compared to typical U.S. regular gasoline at 91-93. Accordingly, high RON ethanol blends containing 20 vol% to 40 vol% ethanol are being extensively studied as fuels that enable design of more efficient engines. These blends are referred to as high-octane fuel (HOF) in this report. HOF could enable dramatic growth in the U.S. ethanol industry, with consequent energy security and GHG emission benefits, while also supporting introduction of more efficient vehicles. HOF could provide the additional ethanol demand necessary for more widespread deployment of cellulosic ethanol. However, the potential of HOF can be realized only if it is adopted by the motor fuel marketplace. This study assesses the feasibility, economics, and logistics of this adoption by the four required participants--drivers, vehicle manufacturers, fuel retailers, and fuel producers. It first assesses the benefits that could motivate these participants to adopt HOF. Then it focuses on the drawbacks and barriers that these participants could face when adopting HOF and proposes strategies--including incentives and

  3. Structural differences of xylans affect their interaction with cellulose

    NARCIS (Netherlands)

    Kabel, M.A.; Borne, van den H.; Vincken, J.P.; Voragen, A.G.J.; Schols, H.A.

    2007-01-01

    The affinity of xylan to cellulose is an important aspect of many industrial processes, e.g. production of cellulose, paper making and bio-ethanol production. However, little is known about the adsorption of structurally different xylans to cellulose. Therefore, the adsorption of various xylans to

  4. Systems biology and pathway engineering enable Saccharomyces cerevisiae to utilize C-5 and C-6 sugars simultaneously for cellulosic ethanol production

    Science.gov (United States)

    Saccharomyces cerevisiae is a traditional industrial workhorse for ethanol production. However, conventional ethanologenic yeast is superior in fermentation of hexose sugars (C-6) such as glucose but unable to utilize pentose sugars (C-5) such as xylose richly embedded in lignocellulosic biomass. In...

  5. Effect of cellulosic sugar degradation products (furfural and hydroxymethylfurfural) on acetone-butanol-ethanol (ABE) fermentation using Clostridium beijerinckii P260

    Science.gov (United States)

    Studies were performed to identify chemicals present in wheat straw hydrolysate (WSH) that enhance acetone butanol ethanol (ABE) productivity. These chemicals were identified as furfural and hydroxymethyl furfural (HMF). Control experiment resulted in the production of 21.09-21.66 gL**-1 ABE with a ...

  6. Recent updates on lignocellulosic biomass derived ethanol - A review

    Directory of Open Access Journals (Sweden)

    Rajeev Kumar

    2016-03-01

    Full Text Available Lignocellulosic (or cellulosic biomass derived ethanol is the most promising near/long term fuel candidate. In addition, cellulosic biomass derived ethanol may serve a precursor to other fuels and chemicals that are currently derived from unsustainable sources and/or are proposed to be derived from cellulosic biomass. However, the processing cost for second generation ethanol is still high to make the process commercially profitable and replicable. In this review, recent trends in cellulosic biomass ethanol derived via biochemical route are reviewed with main focus on current research efforts that are being undertaken to realize high product yields/titers and bring the overall cost down.

  7. Irregular incentives

    International Nuclear Information System (INIS)

    Cicchetti, M.A.

    1993-01-01

    Public utility regulation lacks a formal proxy for the economic profits that can be earned in an effectively competitive market if a firm is efficient or innovative. After all, public utility regulation operated on cost-plus basis. If a utility is efficient or innovative and lowers its costs, its typical reward is to have its rates reduced. This is a perverse incentive to motivate a utility to produce at the most efficient level. In addition, since regulation operates on this cost-plus basis, a utility can increase its net income, all other things being equal, by overinvesting in (or open-quotes gold-platingclose quotes) its system, another perverse incentive. Recognizing these flaws of regulation, academicians, utility executives, regulators, and legislators have tried over the last several years to implement incentive regulation plans that correct such perverse incentives. However, under many of the earnings-sharing or price-regulation incentive plans, the rewards for efficient production are not tied directly to measures under a company's control. In fact, such plans could prove highly detrimental to ratepayers and competitors of the regulated company and its affiliates. An incentive regulation plan that ties an appropriate reward for efficient production to specific efficiency gains is a better proxy of an effectively competitive environment. What's more, it is superior to an incentive plan that rewards circumstances beyond the company's control or self-serving manipulation. This is particularly true if no earnings cap is associated with the reward for efficiency. Rewards for efficient production should be tied to specific actions. A suitable incentive plan does not preclude appropriately derived flexible prices for certain products or services where warranted

  8. Kinetic modeling of cellulosic biomass to ethanol via simultaneous saccharification and fermentation: Part I. Accommodation of intermittent feeding and analysis of staged reactors.

    Science.gov (United States)

    Shao, Xiongjun; Lynd, Lee; Wyman, Charles; Bakker, André

    2009-01-01

    The model of South et al. [South et al. (1995) Enzyme Microb Technol 17(9): 797-803] for simultaneous saccharification of fermentation of cellulosic biomass is extended and modified to accommodate intermittent feeding of substrate and enzyme, cascade reactor configurations, and to be more computationally efficient. A dynamic enzyme adsorption model is found to be much more computationally efficient than the equilibrium model used previously, thus increasing the feasibility of incorporating the kinetic model in a computational fluid dynamic framework in the future. For continuous or discretely fed reactors, it is necessary to use particle conversion in conversion-dependent hydrolysis rate laws rather than reactor conversion. Whereas reactor conversion decreases due to both reaction and exit of particles from the reactor, particle conversion decreases due to reaction only. Using the modified models, it is predicted that cellulose conversion increases with decreasing feeding frequency (feedings per residence time, f). A computationally efficient strategy for modeling cascade reactors involving a modified rate constant is shown to give equivalent results relative to an exhaustive approach considering the distribution of particles in each successive fermenter.

  9. Breaking the Biological Barriers to Cellulosic Ethanol: A Joint Research Agenda. A Research Roadmap Resulting from the Biomass to Biofuels Workshop

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-06-30

    A robust fusion of the agricultural, industrial biotechnology, and energy industries can create a new strategic national capability for energy independence and climate protection. In his State of the Union Address (*Bush 2006), President George W. Bush outlined the Advanced Energy Initiative, which seeks to reduce our national dependence on imported oil by accelerating the development of domestic,renewable alternatives to gasoline and diesel fuels. The president has set a national goal of developing cleaner, cheaper, and more reliable alternative energy sources to substantially replace oil imports in the coming years.Fuels derived from cellulosic biomass—the fibrous, woody, and generally inedible portions of plant matter—offer one such alternative to conventional energy sources that can dramatically impact national economic growth, national energy security, and environmental goals. Cellulosic biomass is an attractive energy feedstock because it is an abundant, domestic, renewable source that can be converted to liquid transportation fuels.These fuels can be used readily by current-generation vehicles and distributed through the existing transportation-fuel infrastructure.

  10. Ethanol production from paper sludge using Kluyveromyces marxianus

    International Nuclear Information System (INIS)

    Madrid, Lina Maria; Quintero Diaz, Juan Carlos

    2011-01-01

    Recycled paper sludge is a promising raw material for ethanol production. In this study, we first evaluated the effects of ethanol concentration, solids load, and cellulose crystallinity on the enzymatic hydrolysis of cellulose to produce reducing sugars. We then evaluated the production of ethanol by either saccharification and simultaneous fermentation (SSF) or separated hydrolysis and fermentation (SHF) using the yeast Kluyveromyces marxianus ATCC 36907. We found that cellulose hydrolysis decreased as ethanol concentrations increased; at 40 g/L ethanol, the reducing sugar production was decreased by 79 %. Hydrolysis also decreased as solids load increased; at 9 % of solids, the cellulose conversion was 76 % of the stoichiometric production. The ethanol yield and cellulose conversion rate were higher with SSF as opposed to SHF processes at 72 h of treatment.

  11. The ethanol pathway from Thermoanaerobacterium saccharolyticum improves ethanol production in Clostridium thermocellum.

    Science.gov (United States)

    Hon, Shuen; Olson, Daniel G; Holwerda, Evert K; Lanahan, Anthony A; Murphy, Sean J L; Maloney, Marybeth I; Zheng, Tianyong; Papanek, Beth; Guss, Adam M; Lynd, Lee R

    2017-07-01

    Clostridium thermocellum ferments cellulose, is a promising candidate for ethanol production from cellulosic biomass, and has been the focus of studies aimed at improving ethanol yield. Thermoanaerobacterium saccharolyticum ferments hemicellulose, but not cellulose, and has been engineered to produce ethanol at high yield and titer. Recent research has led to the identification of four genes in T. saccharolyticum involved in ethanol production: adhE, nfnA, nfnB and adhA. We introduced these genes into C. thermocellum and observed significant improvements to ethanol yield, titer, and productivity. The four genes alone, however, were insufficient to achieve in C. thermocellum the ethanol yields and titers observed in engineered T. saccharolyticum strains, even when combined with gene deletions targeting hydrogen production. This suggests that other parts of T. saccharolyticum metabolism may also be necessary to reproduce the high ethanol yield and titer phenotype in C. thermocellum. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  12. Competitiveness of Brazilian sugarcane ethanol compared to US corn ethanol

    International Nuclear Information System (INIS)

    Crago, Christine L.; Khanna, Madhu; Barton, Jason; Giuliani, Eduardo; Amaral, Weber

    2010-01-01

    Corn ethanol produced in the US and sugarcane ethanol produced in Brazil are the world's leading sources of biofuel. Current US biofuel policies create both incentives and constraints for the import of ethanol from Brazil and together with the cost competitiveness and greenhouse gas intensity of sugarcane ethanol compared to corn ethanol will determine the extent of these imports. This study analyzes the supply-side determinants of cost competitiveness and compares the greenhouse gas intensity of corn ethanol and sugarcane ethanol delivered to US ports. We find that while the cost of sugarcane ethanol production in Brazil is lower than that of corn ethanol in the US, the inclusion of transportation costs for the former and co-product credits for the latter changes their relative competitiveness. We also find that the relative cost of ethanol in the US and Brazil is highly sensitive to the prevailing exchange rate and prices of feedstocks. At an exchange rate of US1=R2.15 the cost of corn ethanol is 15% lower than the delivered cost of sugarcane ethanol at a US port. Sugarcane ethanol has lower GHG emissions than corn ethanol but a price of over $113 per ton of CO 2 is needed to affect competitiveness. (author)

  13. Combined enzyme hydrolysis of cellulose and yeast fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Savarese, J J; Young, S D

    1978-08-01

    The conversion of cellulose, especially waste cellulosics, into utilizable materials, especially liquid fuel, is a most valuable outcome of cellulase technology pioneered at the US Army Laboratories, Natick, Mass. A process design has been proposed by Wilke for the conversion of cellulosic materials to ethanol and single-cell protein (SCP). The estimated ethanol production cost by this process is at the moment slightly more expensive than ethanol derived from petroleum. This paper deals with a process design improvement which will lower production cost for ethanol obtained via a Wilke or similar type system. We report a process by which the cellulase-catalyzed hydrolysis of cellulose to glucose is coupled with the yeast fermentation of the glucose produced to ethanol and SCP. Both processes take place in the same fermentor thus eliminating the need for the separation of glucose and a second reactor.

  14. Cellulose Synthesis in Agrobacterium tumefaciens

    Energy Technology Data Exchange (ETDEWEB)

    Alan R. White; Ann G. Matthysse

    2004-07-31

    We have cloned the celC gene and its homologue from E. coli, yhjM, in an expression vector and expressed the both genes in E. coli; we have determined that the YhjM protein is able to complement in vitro cellulose synthesis by extracts of A. tumefaciens celC mutants, we have purified the YhjM protein product and are currently examining its enzymatic activity; we have examined whole cell extracts of CelC and various other cellulose mutants and wild type bacteria for the presence of cellulose oligomers and cellulose; we have examined the ability of extracts of wild type and cellulose mutants including CelC to incorporate UDP-14C-glucose into cellulose and into water-soluble, ethanol-insoluble oligosaccharides; we have made mutants which synthesize greater amounts of cellulose than the wild type; and we have examined the role of cellulose in the formation of biofilms by A. tumefaciens. In addition we have examined the ability of a putative cellulose synthase gene from the tunicate Ciona savignyi to complement an A. tumefaciens celA mutant. The greatest difference between our knowledge of bacterial cellulose synthesis when we started this project and current knowledge is that in 1999 when we wrote the original grant very few bacteria were known to synthesize cellulose and genes involved in this synthesis were sequenced only from Acetobacter species, A. tumefaciens and Rhizobium leguminosarum. Currently many bacteria are known to synthesize cellulose and genes that may be involved have been sequenced from more than 10 species of bacteria. This additional information has raised the possibility of attempting to use genes from one bacterium to complement mutants in another bacterium. This will enable us to examine the question of which genes are responsible for the three dimensional structure of cellulose (since this differs among bacterial species) and also to examine the interactions between the various proteins required for cellulose synthesis. We have carried out one

  15. Peace Incentives

    DEFF Research Database (Denmark)

    Emmanuel, Nikolas G.

    2015-01-01

    How does economic assistance influence the success or failure of peace processes in Africa? Can economic assistance act as an incentive to facilitate an end to conflict? The literature largely ignores aid as a factor supporting peace processes. In addressing this topic, the current study tries...

  16. Analysis of a Modern Hybrid and an Ancient Sugarcane Implicates a Complex Interplay of Factors in Affecting Recalcitrance to Cellulosic Ethanol Production.

    Directory of Open Access Journals (Sweden)

    Viviane Guzzo de Carli Poelking

    Full Text Available Abundant evidence exists to support a role for lignin as an important element in biomass recalcitrance. However, several independent studies have also shown that factors apart from lignin are also relevant and overall, the relative importance of different recalcitrance traits remains in dispute. In this study we used two genetically distant sugarcane genotypes, and performed a correlational study with the variation in anatomical parameters, cell wall composition, and recalcitrance factors between these genotypes. In addition we also tracked alterations in these characteristics in internodes at different stages of development. Significant differences in the development of the culm between the genotypes were associated with clear differential distributions of lignin content and composition that were not correlated with saccharification and fermentation yield. Given the strong influence of the environment on lignin content and composition, we hypothesized that sampling within a single plant could allow us to more easily interpret recalcitrance and changes in lignin biosynthesis than analysing variations between different genotypes with extensive changes in plant morphology and culm anatomy. The syringyl/guaiacyl (S/G ratio was higher in the oldest internode of the modern genotype, but S/G ratio was not correlated with enzymatic hydrolysis yield nor fermentation efficiency. Curiously we observed a strong positive correlation between ferulate ester level and cellulose conversion efficiency. Together, these data support the hypothesis that biomass enzymatic hydrolysis recalcitrance is governed by a quantitative heritage rather than a single trait.

  17. Feasibility Study for Co-Locating and Integrating Ethanol Production Plants from Corn Starch and Lignocellulosic Feedstocks (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, R.; Ibsen, K.; McAloon, A.; Yee, W.

    2005-01-01

    Analysis of the feasibility of co-locating corn-grain-to-ethanol and lignocellulosic ethanol plants and potential savings from combining utilities, ethanol purification, product processing, and fermentation. Although none of the scenarios identified could produce ethanol at lower cost than a straight grain ethanol plant, several were lower cost than a straight cellulosic ethanol plant.

  18. The cellulose resource matrix.

    Science.gov (United States)

    Keijsers, Edwin R P; Yılmaz, Gülden; van Dam, Jan E G

    2013-03-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where large scale competition can be expected and already is observed for the traditional industries such as the paper industry. Cellulose and lignocellulosic raw materials (like wood and non-wood fibre crops) are being utilised in many industrial sectors. Due to the initiated transition towards biobased economy, these raw materials are intensively investigated also for new applications such as 2nd generation biofuels and 'green' chemicals and materials production (Clark, 2007; Lange, 2007; Petrus & Noordermeer, 2006; Ragauskas et al., 2006; Regalbuto, 2009). As lignocellulosic raw materials are available in variable quantities and qualities, unnecessary competition can be avoided via the choice of suitable raw materials for a target application. For example, utilisation of cellulose as carbohydrate source for ethanol production (Kabir Kazi et al., 2010) avoids the discussed competition with easier digestible carbohydrates (sugars, starch) deprived from the food supply chain. Also for cellulose use as a biopolymer several different competing markets can be distinguished. It is clear that these applications and markets will be influenced by large volume shifts. The world will have to reckon with the increase of competition and feedstock shortage (land use/biodiversity) (van Dam, de Klerk-Engels, Struik, & Rabbinge, 2005). It is of interest - in the context of sustainable development of the bioeconomy - to categorize the already available and emerging lignocellulosic resources in a matrix structure. When composing such "cellulose resource matrix" attention should be given to the quality aspects as well as to the available quantities and practical possibilities of processing the

  19. Refining sweet sorghum to ethanol and sugar: economic trade-offs in the context of North China.

    Science.gov (United States)

    Gnansounou, E; Dauriat, A; Wyman, C E

    2005-06-01

    Reducing the use of non-renewable fossil energy reserves together with improving the environment are two important reasons that drive interest in the use of bioethanol as an automotive fuel. Conversion of sugar and starch to ethanol has been proven at an industrial scale in Brazil and the United States, respectively, and this alcohol has been able to compete with conventional gasoline due to various incentives. In this paper, we examined making ethanol from the sugar extracted from the juice of sweet sorghum and/or from the hemicellulose and cellulose in the residual sorghum bagasse versus selling the sugar from the juice or burning the bagasse to make electricity in four scenarios in the context of North China. In general terms, the production of ethanol from the hemicellulose and cellulose in bagasse was more favorable than burning it to make power, but the relative merits of making ethanol or sugar from the juice was very sensitive to the price of sugar in China. This result was confirmed by both process economics and analysis of opportunity costs. Thus, a flexible plant capable of making both sugar and fuel-ethanol from the juice is recommended. Overall, ethanol production from sorghum bagasse appears very favorable, but other agricultural residues such as corn stover and rice hulls would likely provide a more attractive feedstock for making ethanol in the medium and long term due to their extensive availability in North China and their independence from other markets. Furthermore, the process for residue conversion was based on particular design assumptions, and other technologies could enhance competitiveness while considerations such as perceived risk could impede applications.

  20. Cellulose is not just cellulose

    DEFF Research Database (Denmark)

    Hidayat, Budi Juliman; Felby, Claus; Johansen, Katja Salomon

    2012-01-01

    are not regions where free cellulose ends are more abundant than in the bulk cell wall. In more severe cases cracks between fibrils form at dislocations and it is possible that the increased accessibility that these cracks give is the reason why hydrolysis of cellulose starts at these locations. If acid...... or enzymatic hydrolysis of plant cell walls is carried out simultaneously with the application of shear stress, plant cells such as fibers or tracheids break at their dislocations. At present it is not known whether specific carbohydrate binding modules (CBMs) and/or cellulases preferentially access cellulose...

  1. Alcohol for cellulosic material using plural ferments

    Energy Technology Data Exchange (ETDEWEB)

    Hoge, W H

    1977-02-22

    A process is described for producing ethanol (EtOH) from cellulosic materials by first hydrolyzing the material to sugars and then converting the sugars to alcohol by digestion and fermentation. Thus, fibrous cellulosic material obtained from municipal waste slurry was sterilized by autoclaving, followed by inoculation with Trichoderma viride cellulase and Saccharomyces cerevisiae. From 100 g of raw material, 25 mL of 95% EtOH was produced by this method.

  2. Production of ethanol from hemicellulose fraction of cocksfoot grass using pichia stipitis

    DEFF Research Database (Denmark)

    Njoku, Stephen Ikechukwu; Iversen, Jens Asmus; Uellendahl, Hinrich

    2013-01-01

    liquid hydrolysate to ethanol is essential for economically feasible cellulosic ethanol processes. Fermentation of the separated hemicellulose liquid hydrolysates obtained after the WEx pretreatment was done by Pichia stipitis CBS 6054 (Scheffersomyces stipitis). Results: The fermentation of the WEx...

  3. Aligning ambition and incentives

    DEFF Research Database (Denmark)

    Koch, Alexander; Peyrache, Eloïc

    2011-01-01

    Labor turnover creates longer term career concerns incentives that motivate employees in addition to the short term monetary incentives provided by the current employer. We analyze how these incentives interact, and derive implications for the design of incentive contracts and organizational choice...

  4. Aligning Ambition and Incentives

    DEFF Research Database (Denmark)

    Koch, Alexander; Peyrache, Eloïc

    Labor turnover creates longer term career concerns incentives that motivate employees in addition to the short term monetary incentives provided by the current employer. We analyze how these incentives interact and derive implications for the design of incentive contracts and organizational choice...

  5. Ligno cellulosic-ethanol : a second opinion

    NARCIS (Netherlands)

    Zessen, van E.; Weismann, M.; Bakker, R.R.C.; Elbersen, H.W.; Reith, J.H.; Uil, den H.

    2003-01-01

    Up to now renewable energy sources are primarily used in the Netherlands for electricity production. At the end of the past decade the GAVE programme was launched to facilitate the introduction of climate neutral gaseous and liquid fuels. A comprehensive study by ADL evaluated a large number of

  6. Bio Diesel Cellulosic Ethanol Research Project

    Energy Technology Data Exchange (ETDEWEB)

    Hanlon, Edward A. [County of Hendry, FL (United States); Capece, John C. [County of Hendry, FL (United States); McAvoy, Eugene [County of Hendry, FL (United States); Hodges, Alan Wayne [County of Hendry, FL (United States); Shukla, Sanjay [County of Hendry, FL (United States); Ozores-Hamilton, Monica [County of Hendry, FL (United States); Gilbert, Rob [County of Hendry, FL (United States); Wright, Alan [County of Hendry, FL (United States); Baucum, L. [County of Hendry, FL (United States)

    2017-02-07

    The objective of the project is to create the Hendry County Sustainable Biofuels Center and initiate its research, development, and education programs. The mission is to develop engineering and economic assessment methods to evaluate the natural resources impacts of biomass farming and fuel conversion systems; provide sustainability assessments of specific biofuels productions proposals; develop biomass farming and fuel conversion systems that are compatible with south Florida ecosystem restoration priorities; create ecosystem services opportunities and structures to diversify farm income; monitor the range of research and development activities necessary to the creation of sutstainable biofuels production systems in south Florida, identify gaps in the regional research, and assist in the development and coordination of additional projects to fill out the required knowledge base; prepare the workforce of southwest Florida for employment in biofuels related professions; and assist businesses & governmental design and realize sustainable biofuels projects.

  7. Cellulose Breakdown

    Science.gov (United States)

    Greenler, John; Nye, Leith; Tangen, Travis

    2014-01-01

    Production of liquid fuels such as ethanol from fibrous plant biomass could potentially be a significant sustainable component of the U.S. energy portfolio. Engineers and scientists are actively researching this area, and high school students can engage in this contemporary inquiry process by experimenting with different types of biomass, varying…

  8. γ radiolysis of cellulose acetate

    International Nuclear Information System (INIS)

    Ali, S.M.; Clay, P.G.

    1979-01-01

    The major degradative process in γ-irradiated cellulose acetate is chain scission. For the dry powder the G/sub s/ value (number of scissions per 100 eV of energy absorbed) was found to be 7.1. The water-swollen material was found to degrade at the higher rate of G/sub s/ = 9.45. Additions of ethanol and methanol to the water brought about reductions in G/sub s/, whereas dissolved nitrous oxide produced an increase in G/sub s/. The useful life of cellulose acetate reverse osmosis membranes exposed to γ radiation was estimated by observations of the water permeation rate during irradiation. Membrane breakdown occurred at 15 Mrad in pure water, but the dose to breakdown was extended to 83 Mrad in the presence of 4% methanol. 3 figures, 1 table

  9. Cellulose Insulation

    Science.gov (United States)

    1980-01-01

    Fire retardant cellulose insulation is produced by shredding old newspapers and treating them with a combination of chemicals. Insulating material is blown into walls and attics to form a fiber layer which blocks the flow of air. All-Weather Insulation's founders asked NASA/UK-TAP to help. They wanted to know what chemicals added to newspaper would produce an insulating material capable of meeting federal specifications. TAP researched the query and furnished extensive information. The information contributed to successful development of the product and helped launch a small business enterprise which is now growing rapidly.

  10. Scale up of ethanol production using pulp mill wastewater sludge by cellulase and saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Kunchada Sangasintu; Petchporn Chawakitchareon

    2010-01-01

    This study aimed to evaluate the potential use of pulp mill wastewater sludge as substrate in ethanol production. The simultaneous saccharification and fermentation process was conducted by using Saccharomyces cerevisiae TISTR 5339 under optimum proportion of cellulase and pulp mill wastewater sludge. The ethanol production from cellulosic materials in simultaneous saccharification and fermentation needs cooperation between cellulase and yeast. The cellulase hydrolyzes cellulose to sugar while yeast utilizes sugar to produce ethanol. The pulp mill wastewater sludge has an average content of 73.3 % hemi cellulose, 67.1 % alpha cellulose, 4.7 % beta cellulose and 1.4 % gamma cellulose. The experimental results indicated that the volume of the ethanol tend to increase with time, providing the maximum ethanol yield of 0.69 g/g on the 7"t"h day, the last day of the experiment. The ethanol production was scaled up in 5 L fermentor under optimum proportion and increased the fermentation period. It was found that the ethanol production gave the maximum ethanol yield of 1.14 g/g on the 9"t"h day of the totally 13 days experimentation. These results showed that the cellulose from pulp mill wastewater sludge was as effective substrate for ethanol production and alternative energy for the future. (author)

  11. Cellulose Perversions

    Directory of Open Access Journals (Sweden)

    Maria H. Godinho

    2013-03-01

    Full Text Available Cellulose micro/nano-fibers can be produced by electrospinning from liquid crystalline solutions. Scanning electron microscopy (SEM, as well as atomic force microscopy (AFM and polarizing optical microscopy (POM measurements showed that cellulose-based electrospun fibers can curl and twist, due to the presence of an off-core line defect disclination, which was present when the fibers were prepared. This permits the mimicking of the shapes found in many systems in the living world, e.g., the tendrils of climbing plants, three to four orders of magnitude larger. In this work, we address the mechanism that is behind the spirals’ and helices’ appearance by recording the trajectories of the fibers toward diverse electrospinning targets. The intrinsic curvature of the system occurs via asymmetric contraction of an internal disclination line, which generates different shrinkages of the material along the fiber. The completely different instabilities observed for isotropic and anisotropic electrospun solutions at the exit of the needle seem to corroborate the hypothesis that the intrinsic curvature of the material is acquired during liquid crystalline sample processing inside the needle. The existence of perversions, which joins left and right helices, is also investigated by using suspended, as well as flat, targets. Possible routes of application inspired from the living world are addressed.

  12. Pretreatment of Reed by Wet Oxidation and Subsequent Utilization of the Pretreated Fibers for Ethanol Production

    DEFF Research Database (Denmark)

    Szijarto, Nora; Kádár, Zsófia; Varga, Eniko

    2009-01-01

    lignocelluloses usually do. In the present study, wet oxidation was investigated as the pretreatment method to enhance the enzymatic digestibility of reed cellulose to soluble sugars and thus improve the convertibility of reed to ethanol. The most effective treatment increased the digestibility of reed cellulose...... of cellulose to glucose was 82.4%. Simultaneous saccharification and fermentation of pretreated solids resulted in a final ethanol concentration as high as 8.7 g/L, yielding 73% of the theoretical....

  13. Incentive delegation and collusion

    NARCIS (Netherlands)

    Mukherjee, A.

    2000-01-01

    In an infinitely repeated duopoly the implications of strategic incentive delegation are shown. Whether incentive delegation makes consumers or producers better-off depends on the nature of competition. WeThe presence or absence of incentive delegation may affect the interests of the consumers and

  14. Establishing an ethanol production business

    International Nuclear Information System (INIS)

    1993-01-01

    Many Saskatchewan communities are interested in the potential benefits of establishing an ethanol production facility. A guide is presented to outline areas that communities should consider when contemplating the development of an ethanol production facility. Political issues affecting the ethanol industry are discussed including environmental impacts, United States legislation, Canadian legislation, and government incentives. Key success factors in starting a business, project management, marketing, financing, production, physical requirements, and licensing and regulation are considered. Factors which must be taken into consideration by the project manager and team include markets for ethanol and co-products, competent business management staff, equity partners for financing, production and co-product utilization technologies, integration with another facility such as a feedlot or gluten plant, use of outside consultants, and feedstock, water, energy, labour, environmental and site size requirements. 2 figs., 2 tabs

  15. Ethanol Basics

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-01-30

    Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

  16. Ethanol annual report FY 1990

    Energy Technology Data Exchange (ETDEWEB)

    Texeira, R.H.; Goodman, B.J. (eds.)

    1991-01-01

    This report summarizes the research progress and accomplishments of the US Department of Energy (DOE) Ethanol from Biomass Program, field managed by the Solar Energy Research Institute, during FY 1990. The report includes an overview of the entire program and summaries of individual research projects. These projects are grouped into the following subject areas: technoeconomic analysis; pretreatment; cellulose conversion; xylose fermentation; and lignin conversion. Individual papers have been indexed separately for inclusion on the data base.

  17. Biohydrogen, bioelectricity and bioalcohols from cellulosic materials

    Energy Technology Data Exchange (ETDEWEB)

    Nissila, M.

    2013-03-01

    The demand for renewable energy is increasing due to increasing energy demand and global warming associated with increasing use of fossil fuels. Renewable energy can be derived from biological production of energy carriers from cellulosic biomass. These biochemical processes include biomass fermentation to hydrogen, methane and alcohols, and bioelectricity production in microbial fuel cells (MFCs). The objective of this study was to investigate the production of different energy carriers (hydrogen, methane, ethanol, butanol, bioelectricity) through biochemical processes. Hydrogen production potential of a hot spring enrichment culture from different sugars was determined, and hydrogen was produced continuously from xylose. Cellulolytic and hydrogenic cultures were enriched on cellulose, cellulosic pulp materials, and on silage at different process conditions. The enrichment cultures were further characterized. The effect of acid pretreatment on hydrogen production from pulp materials was studied and compared to direct pulp fermentation to hydrogen. Electricity and alcohol(s) were simultaneously produced from xylose in MFCs and the exoelectrogenic and alcohologenic enrichment cultures were characterized. In the end, the energy yields obtained from different biochemical processes were determined and compared. In this study, cultures carrying out simultaneous cellulose hydrolysis and hydrogen fermentation were enriched from different sources at different operational conditions. These cultures were successfully utilized for cellulose to hydrogen fermentation in batch systems. Based on these results further research should be conducted on continuous hydrogen production from cellulosic materials.

  18. Microbiology and physiology of anaerobic fermentations of cellulose. Progress report, September 1, 1979-May 15, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Peck, H.D. Jr.; Ljungdahl, L.G.

    1980-01-01

    Reseach progress is reported for the period September, 1979 to May, 1980. Studies on the mesophilic and thermophilic microorganisms fermenting cellulose to various products (ethanol, acetate, CO/sub 2/, H/sub 2/, and methane) are summarized. (ACR)

  19. Cellulose conversion of corn pericarp without pretreatment.

    Science.gov (United States)

    Kim, Daehwan; Orrego, David; Ximenes, Eduardo A; Ladisch, Michael R

    2017-12-01

    We report enzyme hydrolysis of cellulose in unpretreated pericarp at a cellulase loading of 0.25FPU/g pericarp solids using a phenol tolerant Aspergillus niger pectinase preparation. The overall protein added was 5mg/g and gave 98% cellulose conversion in 72h. However, for double the amount of enzyme from Trichoderma reesei, which is significantly less tolerant to phenols, conversion was only 16%. The key to achieving high conversion without pretreatment is combining phenol inhibition-resistant enzymes (such as from A. niger) with unground pericarp from which release of phenols is minimal. Size reduction of the pericarp, which is typically carried out in a corn-to-ethanol process, where corn is first ground to a fine powder, causes release of highly inhibitory phenols that interfere with cellulase enzyme activity. This work demonstrates hydrolysis without pretreatment of large particulate pericarp is a viable pathway for directly producing cellulose ethanol in corn ethanol plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Marine Corps Pay Incentives

    Science.gov (United States)

    Marines from 2000 to 2017. The thesis includes a literature review on economic theory related to pay incentives in the Department of Defense, a...The purpose of this thesis to provide the Marine Corps with a comprehensive report on pay incentive programs and special pay that were available to...summarization of pay incentive categories, a data analysis on take-up rates and average annual amounts at the end of each fiscal year, and a program review

  1. Anhydrous ethanol: A renewable source of energy

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Santosh; Singh, Neetu; Prasad, Ram [Department of Chemical Engineering, H. B. Technological Institute, Kanpur 208002 (India)

    2010-09-15

    Anhydrous ethanol is one of the biofuels produced today and it is a subset of renewable energy. It is considered to be an excellent alternative clean-burning fuel to gasoline. Anhydrous ethanol is commercially produced by either catalytic hydration of ethylene or fermentation of biomass. Any biological material that has sugar, starch or cellulose can be used as biomass for producing anhydrous ethanol. Since ethanol-water solution forms a minimum-boiling azeotrope of composition of 89.4 mol% ethanol and 10.6 mol% water at 78.2 C and standard atmospheric pressure, the dilute ethanol-water solutions produced by fermentation process can be continuously rectified to give at best solutions containing 89.4 mol% ethanol at standard atmospheric pressure. Therefore, special process for removal of the remaining water is required for manufacture of anhydrous ethanol. Various processes for producing anhydrous ethanol have been used/suggested. These include: (i) chemical dehydration process, (ii) dehydration by vacuum distillation process, (iii) azeotropic distillation process, (iv) extractive distillation processes, (v) membrane processes, (vi) adsorption processes and (vii) diffusion distillation process. These processes of manufacturing anhydrous ethanol have been improved continuously due to the increasingly strict requirements for quantity and quality of this product. The literature available on these processes is reviewed. These processes are also compared on the basis of energy requirements. (author)

  2. Characterization of cellulose nanowhiskers

    International Nuclear Information System (INIS)

    Nascimento, Nayra R.; Pinheiro, Ivanei F.; Morales, Ana R.; Ravagnani, Sergio P.; Mei, Lucia

    2015-01-01

    Cellulose is the most abundant polymer earth. The cellulose nanowhiskers can be extracted from the cellulose. These have attracted attention for its use in nanostructured materials for various applications, such as nanocomposites, because they have peculiar characteristics, among them, high aspect ratio, biodegradability and excellent mechanical properties. This work aims to characterize cellulose nanowhiskers from microcrystalline cellulose. Therefore, these materials were characterized by X-ray diffraction (XRD) to assess the degree of crystallinity, infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) to the morphology of nanowhiskers and thermal stability was evaluated by Thermogravimetric Analysis (TGA). (author)

  3. Electrically conductive cellulose composite

    Science.gov (United States)

    Evans, Barbara R.; O'Neill, Hugh M.; Woodward, Jonathan

    2010-05-04

    An electrically conductive cellulose composite includes a cellulose matrix and an electrically conductive carbonaceous material incorporated into the cellulose matrix. The electrical conductivity of the cellulose composite is at least 10 .mu.S/cm at 25.degree. C. The composite can be made by incorporating the electrically conductive carbonaceous material into a culture medium with a cellulose-producing organism, such as Gluconoacetobacter hansenii. The composites can be used to form electrodes, such as for use in membrane electrode assemblies for fuel cells.

  4. Photovoltaic Incentive Design Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, T. E.

    2006-12-01

    Investments in customer-owned grid-connected photovoltaic (PV) energy systems are growing at a steady pace. This is due, in part, to the availability of attractive economic incentives offered by public state agencies and utilities. In the United States, these incentives have largely been upfront lump payments tied to the system capacity rating. While capacity-based ''buydowns'' have stimulated the domestic PV market, they have been criticized for subsidizing systems with potentially poor energy performance. As a result, the industry has been forced to consider alternative incentive structures, particularly ones that pay based on long-term measured performance. The industry, however, lacks consensus in the debate over the tradeoffs between upfront incentive payments versus longer-term payments for energy delivery. This handbook is designed for agencies and utilities that offer or intend to offer incentive programs for customer-owned PV systems. Its purpose is to help select, design, and implement incentive programs that best meet programmatic goals. The handbook begins with a discussion of the various available incentive structures and then provides qualitative and quantitative tools necessary to design the most appropriate incentive structure. It concludes with program administration considerations.

  5. Utilization of cellulosic materials through enzymic hydrolysis. 11. Preliminary assessment of an integrated processing scheme

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C R; Cysewski, G R; Yang, R D

    1976-01-01

    An integrated processing scheme is described for the conversion of a cellulose waste (newsprint) to sugars by enzymic hydrolysis and then to ethanol and yeast by fermentation. The unconverted solids are burned to produce process energy requirements and surplus electric power. With the preliminary design at an estimate total capital investment of $33.4 x 10/sup 6/, 95% ethanol may be produced FOB (free on board) the plant for approx.61 cents/gal, assuming zero cost for cellulosic feed; taking into account interest rates and taxes and a cellulose feed cost of $20/ton the figure becomes $1.67/gal.

  6. ETHANOL ORGANOSOLV PRETREATMENT OF BAMBOO FOR EFFICIENT ENZYMATIC SACCHARIFICATION

    Directory of Open Access Journals (Sweden)

    Zhiqiang Li,

    2012-06-01

    Full Text Available Bamboo is a potential lignocellulosic biomass for the production of bioethanol because of its high cellulose and hemicelluloses content. In this research, ethanol organosolv pretreatment with dilute sulfuric acid as the catalyst was studied in order to enhance enzymatic saccharification of moso bamboo. The addition of 2% (w/w bamboo dilute sulfuric acid in 75% ethanol had a particularly strong effect on fractionation of bamboo. It yielded a solids fraction containing 83.4% cellulose in the treated substrate. The cellulose conversion to glucose yield reached 77.1 to 83.4% after enzymatic hydrolysis of the solids fraction for 48 h at an enzyme loading of 15 FPU cellulase/g cellulose and 30 IU β-glucosidase/g cellulose. The enzymatic hydrolysis rate was significantly accelerated as the ethanol organosolv pretreatment time increased, reaching the highest enzymatic glucose yield of 83.4% after 48 h at 50 °C. The concentrations of fermentation inhibitors such as HMF (5-hydroxy-2-methyl furfural and furfural were 0.96 g/L and 4.38 g/L in the spent liquor after the ethanol organosolv pretreatment, which were slightly lower than the concentrations quantified during H2SO4-water treatment. Spent liquor was diluted with water, and more than 87.2% of lignin in raw bamboo was recovered as ethanol organosolv lignin through the filtration process.

  7. Enzymatic hydrolysis and fermentation of agricultural residues to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Mes-Hartree, M.; Hogan, C.M.; Saddler, J.N.

    1984-01-01

    A combined enzymatic hydrolysis and fermentation process was used to convert steam-treated wheat and barley straw to ethanol. Maximum conversion efficiencies were obtained when the substrates were steamed for 90 s. These substrates could yield over 0.4 g ethanol/g cellulose following a combined enzymatic hydrolysis and fermentation process procedure using culture filtrates derived from Trichoderma harzianum E58. When culture filtrates from Trichoderma reesei C30 and T. reesei QM9414 were used, the ethanol yields obtained were 0.32 and 0.12 g ethanol/g cellulose utilized, respectively. The lower ethanol yields obtained with these strains were attributed to the lower amounts of ..beta..-glucosidase detected in the T. reesei culture filtrates.

  8. Effect of various carbon and nitrogen sources on cellulose synthesis ...

    African Journals Online (AJOL)

    The effect of various carbon and nitrogen sources on cellulose production by Acetobacter lovaniensis HBB5 was examined. In this study, glucose, fructose, sucrose and ethanol as carbon source and yeast extract, casein hydrolysate and ammonium sulphate as nitrogen source were used. Among the carbon sources, ...

  9. Characterization of ethyl cellulose polymer.

    Science.gov (United States)

    Mahnaj, Tazin; Ahmed, Salah U; Plakogiannis, Fotios M

    2013-01-01

    Ethyl cellulose (EC) polymer was characterized for its property before considering the interactions with the plasicizer. Ethocel Std.10 FP Premium from Dow chemical company USA was tested for its solubility, morphology and thermal properties. Seven percentage of EC solution in ethanol was found to be the right viscosity used to prepare the film. The EC polymer and EC film without any plasticizers showed almost identical thermal behavior, but in X-ray diffraction showed different arrangements of crystallites and amorphous region. Dynamic mechanical analysis of film showed that without a plasticizer, EC film was not flexible and had very low elongation with high applied force. The aim of the work was to avoid using the commercially available EC dispersions Surelease® and Aquacoat®; both already have additives on it. Instead, Ethocel EC polymer (powder) was characterized in our laboratory in order to find out the properties of polymer before considering the interactions of the polymer with various plasticizers.

  10. Electron beam processing of sugar cane bagasse to cellulose hydrolysis

    International Nuclear Information System (INIS)

    Ribeiro, Marcia A.; Cardoso, Vanessa M.; Mori, Manoel N.; Duarte, Celina L.

    2009-01-01

    Sugarcane bagasse has been considered as a substrate for single cell protein, animal feed, and renewable energy production. Sugarcane bagasse generally contain up to 45% glucose polymer cellulose, 40% hemicelluloses, and 20% lignin. Pure cellulose is readily depolymerised by radiation, but in biomass, the cellulose is intimately bonded with lignin, that protect it from radiation effects. The objective of this study is the evaluation of the electron beam irradiation as a pre-treatment to enzymatic hydrolysis of cellulose in order to facilitate its fermentation and improves the production of ethanol biofuel. Samples of sugarcane bagasse were obtained in sugar/ethanol Iracema Mill sited in Piracicaba, Brazil, and were irradiated using Radiation Dynamics Electron Beam Accelerator with 1.5 MeV energy and 37kW, in batch systems. The applied absorbed doses of the fist sampling, Bagasse A, were 20 kGy, 50 kGy, 100 kGy and 200 kGy. After the evaluation the preliminary obtained results, it was applied lower absorbed doses in the second assay: 5 kGy, 10 kGy, 20 kGy, 30 kGy, 50 kGy, 70 kGy, 100 kGy and 150 kGy. The electron beam processing took to changes in the sugarcane bagasse structure and composition, lignin and cellulose cleavage. The yield of enzymatic hydrolyzes of cellulose increase about 40 % with 30 kGy of absorbed dose. (author)

  11. Cellulose- and xylan-degrading thermophilic anaerobic bacteria from biocompost.

    Science.gov (United States)

    Sizova, M V; Izquierdo, J A; Panikov, N S; Lynd, L R

    2011-04-01

    Nine thermophilic cellulolytic clostridial isolates and four other noncellulolytic bacterial isolates were isolated from self-heated biocompost via preliminary enrichment culture on microcrystalline cellulose. All cellulolytic isolates grew vigorously on cellulose, with the formation of either ethanol and acetate or acetate and formate as principal fermentation products as well as lactate and glycerol as minor products. In addition, two out of nine cellulolytic strains were able to utilize xylan and pretreated wood with roughly the same efficiency as for cellulose. The major products of xylan fermentation were acetate and formate, with minor contributions of lactate and ethanol. Phylogenetic analyses of 16S rRNA and glycosyl hydrolase family 48 (GH48) gene sequences revealed that two xylan-utilizing isolates were related to a Clostridium clariflavum strain and represent a distinct novel branch within the GH48 family. Both isolates possessed high cellulase and xylanase activity induced independently by either cellulose or xylan. Enzymatic activity decayed after growth cessation, with more-rapid disappearance of cellulase activity than of xylanase activity. A mixture of xylan and cellulose was utilized simultaneously, with a significant synergistic effect observed as a reduction of lag phase in cellulose degradation.

  12. Quantifying Supply Risk at a Cellulosic Biorefinery

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Jason K [Idaho National Laboratory; Jacobson, Jacob Jordan [Idaho National Laboratory; Cafferty, Kara Grace [Idaho National Laboratory; Lamers, Patrick [Idaho National Laboratory; Roni, MD S [Idaho National Laboratory

    2015-03-01

    In order to increase the sustainability and security of the nation’s energy supply, the U.S. Department of Energy through its Bioenergy Technology Office has set a vision for one billion tons of biomass to be processed for renewable energy and bioproducts annually by the year 2030. The Renewable Fuels Standard limits the amount of corn grain that can be used in ethanol conversion sold in the U.S, which is already at its maximum. Therefore making the DOE’s vision a reality requires significant growth in the advanced biofuels industry where currently three cellulosic biorefineries convert cellulosic biomass to ethanol. Risk mitigation is central to growing the industry beyond its infancy to a level necessary to achieve the DOE vision. This paper focuses on reducing the supply risk that faces a firm that owns a cellulosic biorefinery. It uses risk theory and simulation modeling to build a risk assessment model based on causal relationships of underlying, uncertain, supply driving variables. Using the model the paper quantifies supply risk reduction achieved by converting the supply chain from a conventional supply system (bales and trucks) to an advanced supply system (depots, pellets, and trains). Results imply that the advanced supply system reduces supply system risk, defined as the probability of a unit cost overrun, from 83% in the conventional system to 4% in the advanced system. Reducing cost risk in this nascent industry improves the odds of realizing desired growth.

  13. Quantifying Supply Risk at a Cellulosic Biorefinery

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Jason K.; Jacobson, Jacob J.; Cafferty, Kara G.; Lamers, Patrick; Roni, Mohammad S.

    2015-07-01

    In order to increase the sustainability and security of the nation’s energy supply, the U.S. Department of Energy through its Bioenergy Technology Office has set a vision for one billion tons of biomass to be processed for renewable energy and bioproducts annually by the year 2030. The Renewable Fuels Standard limits the amount of corn grain that can be used in ethanol conversion sold in the U.S, which is already at its maximum. Therefore making the DOE’s vision a reality requires significant growth in the advanced biofuels industry where currently three cellulosic biorefineries convert cellulosic biomass to ethanol. Risk mitigation is central to growing the industry beyond its infancy to a level necessary to achieve the DOE vision. This paper focuses on reducing the supply risk that faces a firm that owns a cellulosic biorefinery. It uses risk theory and simulation modeling to build a risk assessment model based on causal relationships of underlying, uncertain, supply driving variables. Using the model the paper quantifies supply risk reduction achieved by converting the supply chain from a conventional supply system (bales and trucks) to an advanced supply system (depots, pellets, and trains). Results imply that the advanced supply system reduces supply system risk, defined as the probability of a unit cost overrun, from 83% in the conventional system to 4% in the advanced system. Reducing cost risk in this nascent industry improves the odds of realizing desired growth.

  14. Synthesis and characterization of amorphous cellulose from triacetate of cellulose

    International Nuclear Information System (INIS)

    Vega-Baudrit, Jose; Sibaja, Maria; Nikolaeva, Svetlana; Rivera A, Andrea

    2014-01-01

    It was carried-out a study for the synthesis and characterization of amorphous cellulose starting from cellulose triacetate. X-rays diffraction was used in order to obtain the cellulose crystallinity degree, also infrared spectroscopy FTIR was used. (author)

  15. CELLULOSIC NANOCOMPOSITES: A REVIEW

    Directory of Open Access Journals (Sweden)

    Martin A. Hubbe

    2008-08-01

    Full Text Available Because of their wide abundance, their renewable and environmentally benign nature, and their outstanding mechanical properties, a great deal of attention has been paid recently to cellulosic nanofibrillar structures as components in nanocomposites. A first major challenge has been to find efficient ways to liberate cellulosic fibrils from different source materials, including wood, agricultural residues, or bacterial cellulose. A second major challenge has involved the lack of compatibility of cellulosic surfaces with a variety of plastic materials. The water-swellable nature of cellulose, especially in its non-crystalline regions, also can be a concern in various composite materials. This review of recent work shows that considerable progress has been achieved in addressing these issues and that there is potential to use cellulosic nano-components in a wide range of high-tech applications.

  16. Rewards and Performance Incentives.

    Science.gov (United States)

    Zigon, Jack

    1994-01-01

    Discusses rewards and performance incentives for employees, including types of rewards; how rewards help in managing; dysfunctional awards; selecting the right reward; how to find rewards that fit; and delivering rewards effectively. Examples are included. (three references) (LRW)

  17. Internally plasticised cellulose polymers

    International Nuclear Information System (INIS)

    Burnup, M.; Hayes, G.F.; Fydelor, P.J.

    1981-01-01

    Plasticised cellulose polymers comprise base polymer having a chain of β-anhydroglucose units joined by ether linkages, with at least one of said units carrying at least one chemically unreactive side chain derived from an allylic monomer or a vinyl substituted derivative of ferrocene. The side chains are normally formed by radiation grafting. These internally plasticised celluloses are useful in particular as inhibitor coatings for rocket motor propellants and in general wherever cellulose polymers are employed. (author)

  18. Potential of giant reed (Arundo donax L. for second generation ethanol production

    Directory of Open Access Journals (Sweden)

    Claudia Fernanda Lemons e Silva

    2015-01-01

    Conclusions: The fermentability of the pretreated biomass was performed successfully through the conception of simultaneous saccharification and fermentation resulting in approximately 75 L of ethanol per ton of cellulose.

  19. Versatile High-Performance Regenerated Cellulose Membranes Prepared using Trimethylsilyl Cellulose as a Precursor

    KAUST Repository

    Puspasari, Tiara

    2018-05-01

    with a good compatibility. The cellulose–PDMS membranes demonstrate attractive performance in ethanol-water pervaporation as compared to the commercial PDMS membrane, and allow nanofiltration of a wide range of solvents with different polarity. The cellulose-PEI membranes exhibit anomalous performance improvement in nanofiltration as compared to the corresponding pure membranes. This study has opened up many great opportunities for cellulose to continuously contribute to sustainable and economical membrane processes.

  20. The Canadian Petroleum Products Institute : position on ethanol

    International Nuclear Information System (INIS)

    2002-01-01

    A brief overview of the Canadian Petroleum Products Institute (CPPI), an industry association which represents Canadian Petroleum Refiners and Marketers is provided. It is not against nor for the use of ethanol as a fuel. Ethanol blends are marketed by some CPPI members. It is mentioned that consumers accept ethanol fuels when the price is competitive with the price of non-ethanol fuel. Mandating the use of ethanol in fuels is not an issue supported by the CPPI. A subsidy is required in order for ethanol to be an economically attractive option, and the consumers would be forced to bear subsidy costs if the use of ethanol in fuels were to be mandated. The technology is still some years away for ethanol from cellulose to be an attractive option. It is difficult to finance new plants, and 50 million of the 240 million litres of ethanol blended has to be imported. The advantages of ethanol as a fuel are marginal and not cost effective. Some changes to the gasoline distribution system would be required, as ethanol must be added near the consumer, and it may not be appropriate for some older vehicles and some off-road equipment. The gasoline industry's flexibility would be reduced by provincial mandates. Several questions have not yet been answered, such as what is the real purpose of mandating ethanol in motor fuels? when will new technology be available? The CPPI makes four recommendations: (1) the development of a clear understanding of and the articulation of the objectives of a new ethanol policy, (2) support the development of new cellulose based technology, (3) take a prudent and gradual approach to development of a new policy, and (4) CPPI does not believe that an ethanol mandate is in the best interests of all Canadians

  1. Beyond commonplace biofuels: Social aspects of ethanol

    International Nuclear Information System (INIS)

    Ribeiro, Barbara Esteves

    2013-01-01

    Biofuels policies and projects may lead to environmental, economic and social impacts. A number of studies point out the need to deliver comprehensive sustainability assessments regarding biofuels, with some presenting analytical frameworks that claim to be exhaustive. However, what is often found in the literature is an overexploitation of environmental and economic concerns, by contrast to a limited appraisal of the social aspects of biofuels. Building on a systematic review of the peer-reviewed literature, this paper discusses the social constraints and strengths of ethanol, with regard to the product's lifecycle stages and the actors involved. Its objective is to contribute to the development of social frameworks to be used in assessing the impact of ethanol. Main findings indicate that ethanol developments can increase the levels of social vulnerability, although there is little evidence in the literature regarding the positive and negative social impacts of 1st-generation ethanol and potential impacts of cellulosic ethanol. Further work is needed on the formulation of social criteria and indicators for a comprehensive sustainability assessment of this biofuel. Policy makers need to internalise the social dimension of ethanol in decision-making to prevent public opposition and irreversible social costs in the future. - Highlights: ► The literature lacks evidence on the social impacts of ethanol. ► Further work is needed on social criteria and indicators for assessment. ► Ethanol developments can increase the levels of social vulnerability. ► Decision-making should internalise the social dimension of biofuels sustainability

  2. Effects of Fuel Ethanol Use on Fuel-Cycle Energy and Greenhouse Gas Emissions; TOPICAL

    International Nuclear Information System (INIS)

    C. Saricks; D. Santini; M. Wang

    1999-01-01

    We estimated the effects on per-vehicle-mile fuel-cycle petroleum use, greenhouse gas (GHG) emissions, and energy use of using ethanol blended with gasoline in a mid-size passenger car, compared with the effects of using gasoline in the same car. Our analysis includes petroleum use, energy use, and emissions associated with chemicals manufacturing, farming of corn and biomass, ethanol production, and ethanol combustion for ethanol; and petroleum use, energy use, and emissions associated with petroleum recovery, petroleum refining, and gasoline combustion for gasoline. For corn-based ethanol, the key factors in determining energy and emissions impacts include energy and chemical usage intensity of corn farming, energy intensity of the ethanol plant, and the method used to estimate energy and emissions credits for co-products of corn ethanol. The key factors in determining the impacts of cellulosic ethanol are energy and chemical usage intensity of biomass farming, ethanol yield per dry ton of biomass, and electricity credits in cellulosic ethanol plants. The results of our fuel-cycle analysis for fuel ethanol are listed below. Note that, in the first half of this summary, the reductions cited are per-vehicle-mile traveled using the specified ethanol/gasoline blend instead of conventional (not reformulated) gasoline. The second half of the summary presents estimated changes per gallon of ethanol used in ethanol blends. GHG emissions are global warming potential (GWP)-weighted, carbon dioxide (CO2)-equivalent emissions of CO2, methane (CH4), and nitrous oxide (N2O)

  3. Effects of Fuel Ethanol Use on Fuel-Cycle Energy and Greenhouse Gas Emissions

    International Nuclear Information System (INIS)

    C. Saricks; D. Santini; M. Wang

    1999-01-01

    We estimated the effects on per-vehicle-mile fuel-cycle petroleum use, greenhouse gas (GHG) emissions, and energy use of using ethanol blended with gasoline in a mid-size passenger car, compared with the effects of using gasoline in the same car. Our analysis includes petroleum use, energy use, and emissions associated with chemicals manufacturing, farming of corn and biomass, ethanol production, and ethanol combustion for ethanol; and petroleum use, energy use, and emissions associated with petroleum recovery, petroleum refining, and gasoline combustion for gasoline. For corn-based ethanol, the key factors in determining energy and emissions impacts include energy and chemical usage intensity of corn farming, energy intensity of the ethanol plant, and the method used to estimate energy and emissions credits for co-products of corn ethanol. The key factors in determining the impacts of cellulosic ethanol are energy and chemical usage intensity of biomass farming, ethanol yield per dry ton of biomass, and electricity credits in cellulosic ethanol plants. The results of our fuel-cycle analysis for fuel ethanol are listed below. Note that, in the first half of this summary, the reductions cited are per-vehicle-mile traveled using the specified ethanol/gasoline blend instead of conventional (not reformulated) gasoline. The second half of the summary presents estimated changes per gallon of ethanol used in ethanol blends. GHG emissions are global warming potential (GWP)-weighted, carbon dioxide (CO2)-equivalent emissions of CO2, methane (CH4), and nitrous oxide (N2O)

  4. The Effect of Cellulose Crystal Structure and Solid-State Morphology on the Activity of Cellulases

    Energy Technology Data Exchange (ETDEWEB)

    Stipanovic, Arthur J [SUNY College of Environmental Science and Forestry

    2014-11-17

    Consistent with the US-DOE and USDA “Roadmap” objective of producing ethanol and chemicals from cellulosic feedstocks more efficiently, a three year research project entitled “The Effect of Cellulose Crystal Structure and Solid-State Morphology on the Activity of Cellulases” was initiated in early 2003 under DOE sponsorship (Project Number DE-FG02-02ER15356). A three year continuation was awarded in June 2005 for the period September 15, 2005 through September 14, 2008. The original goal of this project was to determine the effect of cellulose crystal structure, including allomorphic crystalline form (Cellulose I, II, III, IV and sub-allomorphs), relative degree of crystallinity and crystallite size, on the activity of different types of genetically engineered cellulase enzymes to provide insight into the mechanism and kinetics of cellulose digestion by “pure” enzymes rather than complex mixtures. We expected that such information would ultimately help enhance the accessibility of cellulose to enzymatic conversion processes thereby creating a more cost-effective commercial process yielding sugars for fermentation into ethanol and other chemical products. Perhaps the most significant finding of the initial project phase was that conversion of native bacterial cellulose (Cellulose I; BC-I) to the Cellulose II (BC-II) crystal form by aqueous NaOH “pretreatment” provided an increase in cellulase conversion rate approaching 2-4 fold depending on enzyme concentration and temperature, even when initial % crystallinity values were similar for both allomorphs.

  5. Expanded ethanol production: Implications for agriculture, water demand, and water quality

    International Nuclear Information System (INIS)

    De La Torre Ugarte, Daniel G.; He, Lixia; Jensen, Kimberly L.; English, Burton C.

    2010-01-01

    Feedstock production for large scale development of the U.S. ethanol industry and introduction of cellulose-to-ethanol technology will require extensive changes in land use and field management. Hence, this production will likely have significant impact on water demand and quality. This study compares two 'what if' scenarios for attaining a 227.1 hm 3 of ethanol by 2030 and 3.8 hm 3 of biodiesel by 2012. In the first scenario cellulose-to-ethanol technology is introduced in 2012, while in the second scenario the technology is delayed until 2015. Results show that the timing of introduction of cellulose-to-ethanol technology will affect the water use and water quality related input use in primarily in the eastern part of the nation. Results also suggest policy emphasis on reduced and no-till practices needs to be complementary to increased crop residue use. (author)

  6. Ethanol production from wet oxidized corn straw by simultaneous saccharification and fermentation

    DEFF Research Database (Denmark)

    Zhang, Q.; Yin, Y.; Thygesen, Anders

    2010-01-01

    remained in the solid fraction and recovery of cellulose was 95.87% after pretreatment. After 24 h hydrolysis at 50°C using cellulase, the achieved conversion of cellulose to glucose was about 67.6%. After 142 h of SSF with substrate concentration of 8%, ethanol yield of 79.0% of the theoretical...

  7. Fuel ethanol production from wet oxidised corn stover by S. cerevisiae

    DEFF Research Database (Denmark)

    Qiang, zhang; Thomsen, Anne Belinda

    2012-01-01

    of 74.6% were obtained after pretreatment. 86.5% of cellulose was remained in the solid cake. After 24h hydrolysis at 50°C using cellulase (Cellubrix L), the achieved conversion of cellulose to glucose was 64.8%. Ethanol production was evaluated from dried solid cake and the hydrolysate was employed...

  8. Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate

    Energy Technology Data Exchange (ETDEWEB)

    Binder, Thomas [Archer Daniels Midland Company, Decatur, IL (United States); Erpelding, Michael [Archer Daniels Midland Company, Decatur, IL (United States); Schmid, Josef [Archer Daniels Midland Company, Decatur, IL (United States); Chin, Andrew [Archer Daniels Midland Company, Decatur, IL (United States); Sammons, Rhea [Archer Daniels Midland Company, Decatur, IL (United States); Rockafellow, Erin [Archer Daniels Midland Company, Decatur, IL (United States)

    2015-04-10

    Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate. The purpose of Archer Daniels Midlands Integrated Biorefinery (IBR) was to demonstrate a modified acetosolv process on corn stover. It would show the fractionation of crop residue to distinct fractions of cellulose, hemicellulose, and lignin. The cellulose and hemicellulose fractions would be further converted to ethanol as the primary product and a fraction of the sugars would be catalytically converted to acrylic acid, with butyl acrylate the final product. These primary steps have been demonstrated.

  9. Cellulose binding domain proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc; Doi, Roy

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  10. Cellulose Degradation by Cellulose-Clearing and Non-Cellulose-Clearing Brown-Rot Fungi

    OpenAIRE

    Highley, Terry L.

    1980-01-01

    Cellulose degradation by four cellulose-clearing brown-rot fungi in the Coniophoraceae—Coniophora prasinoides, C. puteana, Leucogyrophana arizonica, and L. olivascens—is compared with that of a non-cellulose-clearing brown-rot fungus, Poria placenta. The cellulose- and the non-cellulose-clearing brown-rot fungi apparently employ similar mechanisms to depolymerize cellulose; most likely a nonenzymatic mechanism is involved.

  11. Electrospinning cellulose based nanofibers for sensor applications

    Science.gov (United States)

    Nartker, Steven

    2009-12-01

    Bacterial pathogens have recently become a serious threat to the food and water supply. A biosensor based on an electrochemical immunoassay has been developed for detecting food borne pathogens, such as Escherichia coli (E. coli) O157:H7. These sensors consist of several materials including, cellulose, cellulose nitrate, polyaniline and glass fibers. The current sensors have not been optimized in terms of microscale architecture and materials. The major problem associated with the current sensors is the limited concentration range of pathogens that provides a linear response on the concentration conductivity chart. Electrospinning is a process that can be used to create a patterned fiber mat design that will increase the linear range and lower the detection limit of these sensors by improving the microscale architecture. Using the electrospinning process to produce novel mats of cellulose nitrate will offer improved surface area, and the cellulose nitrate can be treated to further improve chemical interactions required for sensor activity. The macro and micro architecture of the sensor is critical to the performance of the sensors. Electrospinning technology can be used to create patterned architectures of nanofibers that will enhance sensor performance. To date electrospinning of cellulose nitrate has not been performed and optimization of the electrospinning process will provide novel materials suitable for applications such as filtration and sensing. The goal of this research is to identify and elucidate the primary materials and process factors necessary to produce cellulose nitrate nanofibers using the electrospinning process that will improve the performance of biosensors. Cellulose nitrate is readily dissolved in common organic solvents such as acetone, tetrahydrofuran (THF) and N,N dimethylformamide (DMF). These solvents can be mixed with other latent solvents such as ethanol and other alcohols to provide a solvent system with good electrospinning behavior

  12. Ethanol production from biomass. Voorlopig nauwelijks ethanolproduktie uit biomassa

    Energy Technology Data Exchange (ETDEWEB)

    Van der Knijff, A; Wildschut, L R [Haskoning Koninklijk Ingenieurs- en Architectenbureau, Nijmegen (Netherlands); Williams, A [Technische Univ. Twente, Enschede (Netherlands)

    1991-04-01

    Fluid fuels, for instance ethanol and methanol, can be produced from agricultural materials and from waste materials. For 37 waste flows (among which scrap from the oil- and fat industry, waste potatoes, withdrawn vegetables, waste wood, straw, roadside grass, vegetables-, fruits- and garden wastes and beet tails) possibilities to produce fuels have been considered. In general, sacchariferous and farinaceous wastes, which could be used for ethanol production, are used for other purposes. Therefore ethanol production from these materials is expensive. Cellulose wastes (for instance straw, wood wastes and paper sludge) can be suitable in the future for ethanol production. But first a cheap method to decompose and hydrolize cellulose has to be developed. 2 figs., 2 ills., 3 refs.

  13. Drilling contracts and incentives

    International Nuclear Information System (INIS)

    Osmundsen, Petter; Sorenes, Terje; Toft, Anders

    2008-01-01

    Shortages of rigs and personnel have encouraged discussion of designing incentive contracts in the drilling sector. However, for the drilling contracts, there are not a large variety of contract types in use. This article describes and analyses incentives for drilling contractors. These are directly represented by the compensation formats utilised in the present and in the consecutive drilling contracts. Indirectly, incentives are also provided by the evaluation criteria that oil companies use for awarding drilling assignments. Changes in contract format pose a number of relevant questions relating to resource management, and the article takes an in-depth look at some of these. Do evaluation criteria for awarding drilling assignments encourage the development of new technology and solutions? How will a stronger focus on drilling efficiency influence reservoir utilisation?

  14. Cost incentives for doctors

    DEFF Research Database (Denmark)

    Schottmüller, Christoph

    2013-01-01

    If doctors take the costs of treatment into account when prescribing medication, their objectives differ from their patients' objectives because the patients are insured. This misalignment of interests hampers communication between patient and doctor. Giving cost incentives to doctors increases...... welfare if (i) the doctor's examination technology is sufficiently good or (ii) (marginal) costs of treatment are high enough. If the planner can costlessly choose the extent to which doctors take costs into account, he will opt for less than 100%. Optimal health care systems should implement different...... degrees of cost incentives depending on type of disease and/or doctor....

  15. Incentives and Earnings Growth

    DEFF Research Database (Denmark)

    Frederiksen, Anders

    2013-01-01

    The career prospects of newly recruited employees differ substantially within an organization. The stars experience considerable growth in earnings; others can hardly maintain their entry salaries. This article sheds light on the mechanisms generating the observed heterogeneity in earnings growth...... by investigating the effects that explicit short-run incentives and implicit incentives have on earnings growth. The model’s predictions are tested using personnel records from a large bank and are found to be consistent with the observed earnings growth during the first half of the employees’ careers....

  16. Improving ethanol productivity through self-cycling fermentation of yeast: a proof of concept.

    Science.gov (United States)

    Wang, Jie; Chae, Michael; Sauvageau, Dominic; Bressler, David C

    2017-01-01

    The cellulosic ethanol industry has developed efficient strategies for converting sugars obtained from various cellulosic feedstocks to bioethanol. However, any further major improvements in ethanol productivity will require development of novel and innovative fermentation strategies that enhance incumbent technologies in a cost-effective manner. The present study investigates the feasibility of applying self-cycling fermentation (SCF) to cellulosic ethanol production to elevate productivity. SCF is a semi-continuous cycling process that employs the following strategy: once the onset of stationary phase is detected, half of the broth volume is automatically harvested and replaced with fresh medium to initiate the next cycle. SCF has been shown to increase product yield and/or productivity in many types of microbial cultivation. To test whether this cycling process could increase productivity during ethanol fermentations, we mimicked the process by manually cycling the fermentation for five cycles in shake flasks, and then compared the results to batch operation. Mimicking SCF for five cycles resulted in regular patterns with regards to glucose consumption, ethanol titer, pH, and biomass production. Compared to batch fermentation, our cycling strategy displayed improved ethanol volumetric productivity (the titer of ethanol produced in a given cycle per corresponding cycle time) and specific productivity (the amount of ethanol produced per cellular biomass) by 43.1 ± 11.6 and 42.7 ± 9.8%, respectively. Five successive cycles contributed to an improvement of overall productivity (the aggregate amount of ethanol produced at the end of a given cycle per total processing time) and the estimated annual ethanol productivity (the amount of ethanol produced per year) by 64.4 ± 3.3 and 33.1 ± 7.2%, respectively. This study provides proof of concept that applying SCF to ethanol production could significantly increase productivities, which will help strengthen the

  17. Perspectives on fuel ethanol consumption and trade

    International Nuclear Information System (INIS)

    Walter, Arnaldo; Dolzan, Paulo; Piacente, Erik; Borges da Cunha, Kamyla; Rosillo-Calle, Frank

    2008-01-01

    Since the year 2000 or so there has been a rapid growth on fuel ethanol production and consumption, particularly in US and Brazil. Ethanol trade represented about 10% of world consumption in 2005, Brazil being the main exporter. The most important consumer markets - US and European Union (EU) - have trade regimes that constrained the comparative advantages of the most efficient producers, such as Brazil. This paper evaluates the fuel ethanol market up to 2030 together with the potential for international biotrade. Based on forecasts of gasoline consumption and on targets and mandates of fuel ethanol use, it is estimated that demand could reach 272 Gl in 2030, displacing 10% of the estimated demand of gasoline (Scenario 1), or even 566 Gl in the same year, displacing about 20% of the gasoline demand (Scenario 2). The analysis considers fuel ethanol consumption and production in US, EU-25, Japan, China, Brazil and the rest of the world (ROW-BR). Without significant production of ethanol from cellulosic materials in this period, displacing 10% of the gasoline demand in 2030, at reasonable cost, can only be accomplished by fostering fuel ethanol production in developing countries and enhancing ethanol trade. If the US and EU-25 reach their full production potential (based on conventional routes), the minimum amount that could be traded in 2030 would be about 34 Gl. Displacing 20% of the gasoline demand by 2030 will require the combined development of second-generation technologies and large-scale international trade in ethanol fuel. Without second-generation technologies, Scenario 2 could become a reality only with large-scale production of ethanol from sugarcane in developing countries, e.g., Brazil and ROW-BR could be able to export at least 14.5 Gl in 2010, 73.9 Gl in 2020 and 71.8 Gl in 2030. (author)

  18. Tax Incentives : Using Tax Incentives to Attract Foreign Direct Investment

    OpenAIRE

    Morisset, Jacques

    2003-01-01

    The increasing mobility of international firms and the gradual elimination of barriers to global capital flows have stimulated competition among governments to attract foreign direct investment, often through tax incentives. This note reviews the debate about the effectiveness of tax incentives, examining two much-contested questions: can tax incentives attract foreign investment? And what...

  19. Incentives for partitioning, revisited

    International Nuclear Information System (INIS)

    Cloninger, M.O.

    1980-01-01

    The incentives for separating and eliminating various elements from radioactive waste prior to final geologic disposal were investigated. Exposure pathways to humans were defined, and potential radiation doses to an individual living within the region of influence of the underground storage site were calculated. The assumed radionuclide source was 1/5 of the accumulated high-level waste from the US nuclear power economy through the year 2000. The repository containing the waste was assumed to be located in a reference salt site geology. The study required numerous assumptions concerning the transport of radioactivity from the geologic storage site to man. The assumptions used maximized the estimated potential radiation doses, particularly in the case of the intrusion water well scenario, where hydrologic flow field dispersion effects were ignored. Thus, incentives for removing elements from the waste tended to be maximized. Incentives were also maximized by assuming that elements removed from the waste could be eliminated from the earth without risk. The results of the study indicate that for reasonable disposal conditions, incentives for partitioning any elements from the waste in order to minimize the risk to humans are marginal at best

  20. Incentives and moral hazard

    DEFF Research Database (Denmark)

    Wendimu, Mengistu Assefa; Henningsen, Arne; Czekaj, Tomasz Gerard

    2017-01-01

    system and thus, the incentives to the workers. We compare the productivity of these two production schemes using a cross-sectional plot-level data set. As sugarcane production depends on various exogenous factors that are measured as categorical variables (e.g., soil type, cane variety, etc.), we...

  1. Incentives for Recruiters

    Science.gov (United States)

    1992-09-01

    promotions, with prizes for the kids: anything from football ti’kets to trips to Disneyland ." [Ref. 10:p. 68] Any publisher who wants a successful...such as a trip to Disneyland . The latter focuses more on providing an 29 incentive to the carrier to get a certain number of new customers in a short

  2. Dynamic Incentives in Organizations

    DEFF Research Database (Denmark)

    Ruckes, Martin; Rønde, Thomas

    2015-01-01

    to this inertial tendency is either to increase the financial incentives to encourage searching or to accept no searching. The former response increases search efforts and total profits; the latter response has the opposite results. Inertia can be removed by restructuring the firm in period 2, but this may create...

  3. Mergers, managerial incentives, and efficiencies

    OpenAIRE

    Jovanovic, Dragan

    2014-01-01

    We analyze the effects of synergies from horizontal mergers in a Cournot oligopoly where principals provide their agents with incentives to cut marginal costs prior to choosing output. We stress that synergies come at a cost which possibly leads to a countervailing incentive effect: The merged firm's principal may be induced to stifle managerial incentives in order to reduce her agency costs. Whenever this incentive effect dominates the well-known direct synergy effect, synergies actually red...

  4. Incentives Between Firms (and Within)

    OpenAIRE

    Robert Gibbons

    2005-01-01

    This paper reviews the significant progress in Üagency theoryÝ (i.e., the economic theory of incentives) during the 1990s, with an eye toward applications to supply transactions. I emphasize six recent models, in three pairs: (1) new foundations for the theory of incentive contracts, (2) new directions in incentive theory, and (3) new applications to supply transactions. By reviewing these six models, I hope to establish three things. First, the theory of incentive contracts needed and receiv...

  5. Ethanol dehydration

    OpenAIRE

    Ana María Uyazán; Iván Dario Gil; J L Aguilar; Gerardo Rodríguez Niño; Luis Alfonso Caicedo

    2004-01-01

    This review outlines ethanol dehydration processes and their most important characteristics. It also deals with the main operating variables and some criteria used in designing the separation scheme. A differentiation is made between processes involving liquid steam balance in separation operations and those doing it by screening the difference in molecule size. The last part presents a comparison between the three main industrial processes, stressing their stengths and weaknesses from the op...

  6. Ethanol dehydration

    Directory of Open Access Journals (Sweden)

    Ana María Uyazán

    2004-09-01

    Full Text Available This review outlines ethanol dehydration processes and their most important characteristics. It also deals with the main operating variables and some criteria used in designing the separation scheme. A differentiation is made between processes involving liquid steam balance in separation operations and those doing it by screening the difference in molecule size. The last part presents a comparison between the three main industrial processes, stressing their stengths and weaknesses from the operational, energy consumption and industrial services points of view.

  7. Method of saccharifying cellulose

    Science.gov (United States)

    Johnson, E.A.; Demain, A.L.; Madia, A.

    1983-05-13

    A method is disclosed of saccharifying cellulose by incubation with the cellulase of Clostridium thermocellum in a broth containing an efficacious amount of thiol reducing agent. Other incubation parameters which may be advantageously controlled to stimulate saccharification include the concentration of alkaline earth salts, pH, temperature, and duration. By the method of the invention, even native crystalline cellulose such as that found in cotton may be completely saccharified.

  8. Transcriptome profiling of Zymomonas mobilis under ethanol stress

    Directory of Open Access Journals (Sweden)

    He Ming-xiong

    2012-10-01

    Full Text Available Abstract Background High tolerance to ethanol is a desirable characteristics for ethanologenic strains used in industrial ethanol fermentation. A deeper understanding of the molecular mechanisms underlying ethanologenic strains tolerance of ethanol stress may guide the design of rational strategies to increase process performance in industrial alcoholic production. Many extensive studies have been performed in Saccharomyces cerevisiae and Escherichia coli. However, the physiological basis and genetic mechanisms involved in ethanol tolerance for Zymomonas mobilis are poorly understood on genomic level. To identify the genes required for tolerance to ethanol, microarray technology was used to investigate the transcriptome profiling of the ethanologenic Z. mobilis in response to ethanol stress. Results We successfully identified 127 genes which were differentially expressed in response to ethanol. Ethanol up- or down-regulated genes related to cell wall/membrane biogenesis, metabolism, and transcription. These genes were classified as being involved in a wide range of cellular processes including carbohydrate metabolism, cell wall/membrane biogenesis, respiratory chain, terpenoid biosynthesis, DNA replication, DNA recombination, DNA repair, transport, transcriptional regulation, some universal stress response, etc. Conclusion In this study, genome-wide transcriptional responses to ethanol were investigated for the first time in Z. mobilis using microarray analysis.Our results revealed that ethanol had effects on multiple aspects of cellular metabolism at the transcriptional level and that membrane might play important roles in response to ethanol. Although the molecular mechanism involved in tolerance and adaptation of ethanologenic strains to ethanol is still unclear, this research has provided insights into molecular response to ethanol in Z. mobilis. These data will also be helpful to construct more ethanol resistant strains for cellulosic

  9. Ethanol Production from Brewers’ Spent Grain Pretreated by Dilute Phosphoric Acid

    DEFF Research Database (Denmark)

    Rojas-Chamorro, José A.; Cara, Cristóbal; Romero, Inmaculada

    2018-01-01

    of both pretreatment and enzymatic hydrolysis together recovered 92% of total sugars in BSG, mainly solubilized in the prehydrolysate (63%). Escherichia coli SL100 fermented this mixed sugar solution containing hemicellulosic sugars and starchy glucose without previous detoxification with an ethanol yield...... in this work allowed 69% of the total sugars in the BSG to be converted to ethanol....... of 0.40 g/g. Considering also the glucose released from the cellulosic structure and converted to ethanol by a simultaneous saccharification and fermentation process, an overall ethanol yield of 17.9 g of ethanol per 100 g of raw BSG was achieved. Thereby, the process configuration proposed...

  10. The correlation between cellulose allomorphs (I and II) and conversion after removal of hemicellulose and lignin of lignocellulose.

    Science.gov (United States)

    Song, Yanliang; Zhang, Jingzhi; Zhang, Xu; Tan, Tianwei

    2015-10-01

    H2SO4, NaOH and H3PO4 were applied to decompose lignocellulose samples (giant reeds, pennisetum and cotton stalks) to investigate the correlation between cellulose allomorphs (cellulose I and II) and conversion of cellulose. The effect of removal of hemicellulose and lignin on the surface morphology, crystallinity index (CrI), cellulose allomorphs (cellulose I and II), and enzymatic hydrolysis under different pretreatments was also studied. CrI caused by H3PO4 pretreatment reached 11.19%, 24.93% and 8.15% for the three samples, respectively. Corn stalk showed highest conversion of cellulose among three samples, irrespective of the pretreatment used. This accounted for the widely use of corn stalk as the renewable crop substrate to synthesize biofuels like ethanol. CrI of cellulose I (CrI-I) negatively affects cellulose conversion but CrI of cellulose II (CrI-II) positively affects cellulose conversion. It contributes to make the strategy to transform cellulose I to cellulose II and enhancing enzymatic hydrolysis of lignocellulose. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Single-step ethanol production from lignocellulose using novel extremely thermophilic bacteria.

    Science.gov (United States)

    Svetlitchnyi, Vitali A; Kensch, Oliver; Falkenhan, Doris A; Korseska, Svenja G; Lippert, Nadine; Prinz, Melanie; Sassi, Jamaleddine; Schickor, Anke; Curvers, Simon

    2013-02-28

    Consolidated bioprocessing (CBP) of lignocellulosic biomass to ethanol using thermophilic bacteria provides a promising solution for efficient lignocellulose conversion without the need for additional cellulolytic enzymes. Most studies on the thermophilic CBP concentrate on co-cultivation of the thermophilic cellulolytic bacterium Clostridium thermocellum with non-cellulolytic thermophilic anaerobes at temperatures of 55°C-60°C. We have specifically screened for cellulolytic bacteria growing at temperatures >70°C to enable direct conversion of lignocellulosic materials into ethanol. Seven new strains of extremely thermophilic anaerobic cellulolytic bacteria of the genus Caldicellulosiruptor and eight new strains of extremely thermophilic xylanolytic/saccharolytic bacteria of the genus Thermoanaerobacter isolated from environmental samples exhibited fast growth at 72°C, extensive lignocellulose degradation and high yield ethanol production on cellulose and pretreated lignocellulosic biomass. Monocultures of Caldicellulosiruptor strains degraded up to 89-97% of the cellulose and hemicellulose polymers in pretreated biomass and produced up to 72 mM ethanol on cellulose without addition of exogenous enzymes. In dual co-cultures of Caldicellulosiruptor strains with Thermoanaerobacter strains the ethanol concentrations rose 2- to 8.2-fold compared to cellulolytic monocultures. A co-culture of Caldicellulosiruptor DIB 087C and Thermoanaerobacter DIB 097X was particularly effective in the conversion of cellulose to ethanol, ethanol comprising 34.8 mol% of the total organic products. In contrast, a co-culture of Caldicellulosiruptor saccharolyticus DSM 8903 and Thermoanaerobacter mathranii subsp. mathranii DSM 11426 produced only low amounts of ethanol. The newly discovered Caldicellulosiruptor sp. strain DIB 004C was capable of producing unexpectedly large amounts of ethanol from lignocellulose in fermentors. The established co-cultures of new Caldicellulosiruptor

  12. Gasoline, diesel, and ethanol biofuels from grasses and plants

    National Research Council Canada - National Science Library

    Gupta, Ram B; Demirbas, Ayhan

    2010-01-01

    ...-generation biofuels obtained from nonfood biomass, such as forest residue, agricultural residue, switchgrass, corn stover, waste wood, and municipal solid wastes. Various technologies are discussed, including cellulosic ethanol, biomass gasification, synthesis of diesel and gasoline, biocrude by hydrothermal liquefaction, bio-oil by fast pyrolysis, and the...

  13. Engineering microorganisms to increase ethanol production by metabolic redirection

    Science.gov (United States)

    Deng, Yu; Olson, Daniel G.; van Dijken, Johannes Pieter; Shaw, IV, Arthur J.; Argyros, Aaron; Barrett, Trisha; Caiazza, Nicky; Herring, Christopher D.; Rogers, Stephen R.; Agbogbo, Frank

    2017-10-31

    The present invention provides for the manipulation of carbon flux in a recombinant host cell to increase the formation of desirable products. The invention relates to cellulose-digesting organisms that have been genetically modified to allow the production of ethanol at a high yield by redirecting carbon flux at key steps of central metabolism.

  14. Process for fermentation of ethanol. Verfahren zur Aethanolfermentation

    Energy Technology Data Exchange (ETDEWEB)

    Pemberton, M S; Crawford, S D

    1980-06-19

    The invention concerns an improved process for the manufacture of ethanol from cellulose and substrates containing cellulate with cellulase enzymes and yeast (Candida brassicae ATCC 32196). The cellulase and the micro-organisms producing the alcohol are caused to react simultaneously on the same substrate. The yeast is active below and above 40/sup 0/C.

  15. Ethanol production from Sorghum bicolor using both separate and ...

    African Journals Online (AJOL)

    increase the monomeric sugar during enzymatic hydrolysis and it has been observed that the addition of these surfactants contributed significantly in cellulosic conversion but no effect was shown on hemicellulosic hydrolysis. Fermentability of hydrolyzate was tested using Saccharomyces cerevisiae Ethanol RedTM and it ...

  16. Team incentives in relational contracts

    International Nuclear Information System (INIS)

    Kvaloey, Ola

    2003-01-01

    Incentive schemes for teams are compared. I ask: under which conditions are relational incentive contracts based on joint performance evaluation, relative performance evaluation and independent performance evaluation self-enforceable. The framework of Che and Yoo (2001) on team incentives is combined with the framework of Baker, Gibbons and Murphy (2002) on relational contracts. In a repeated game between one principal and two agents, I find that incentives based on relative or independent performance are expected to dominate when the productivity of effort is high, while joint performance evaluation dominates when productivity is low. Incentives based on independent performance are more probable if the agents own critical assets. (author)

  17. Risk management versus incentives

    International Nuclear Information System (INIS)

    Aven, E.; Lovas, K.; Osmundsen, P.

    2006-01-01

    Portfolio theory indicates that risk management should take place at the group level. Hedging at the project level or in the individual business areas may lead to suboptimal results. However, the efficiency of a profit centre depends on its management's being able to influence factors that are crucial to the unit's financial results. Price hedging could be one such factor. In the wider perspective, this constitutes part of the balancing between centralisation and decentralisation. This article covers important elements of risk management and incentive design. It goes on to discuss the balancing of overall risk management at the group level and incentive design in profit centres and corporate units. Throughout the article, the oil industry serves as a case. (author)

  18. Opposing incentives for collaboration

    DEFF Research Database (Denmark)

    Dorch, Bertil F.; Wien, Charlotte; Larsen, Asger Væring

    , and gives a bonus for publications done through inter-institutionary collaboration. Credits given to universities are fractionalized between the participating universities. So far credits are not assigned to the individual authors but only to their institutions. However, it turns out that research...... collaboration is associated with a higher number of citations than single authorship which may present the author with two opposing incentives for research collaboration....

  19. Incentives and Prosocial Behavior

    OpenAIRE

    Roland Bénabou; Jean Tirole

    2005-01-01

    We develop a theory of prosocial behavior that combines heterogeneity in individual altruism and greed with concerns for social reputation or self-respect. Rewards or punishments (whether material or image-related) create doubt about the true motive for which good deeds are performed, and this ?overjustification effect? can induce a partial or even net crowding out of prosocial behavior by extrinsic incentives. We also identify the settings that are conducive to multiple social norms and, mor...

  20. Incentives and Prosocial Behaviour

    OpenAIRE

    Bénabou, Roland; Tirole, Jean

    2004-01-01

    We build a theory of prosocial behaviour that combines heterogeneity in individual altruism and greed with concerns for social reputation or self-respect. The presence of rewards or punishments creates doubt as to the true motive for which good deeds are performed, and this ‘overjustification effect’ can result in a net crowding out of prosocial behaviour by extrinsic incentives. The model also allows us to identify settings that are conducive to multiple social norms of behaviour, and those ...

  1. Alternative Fuels Data Center: Federal Laws and Incentives for Ethanol

    Science.gov (United States)

    the Office of Management and Budget with opportunities to optimize federal fleet performance, reduce improvements, travel demand management strategies, congestion relief efforts (such as high occupancy vehicle advanced vehicles, fuel blends, fuel economy, hybrid vehicles, and idle reduction. Clean Cities provides

  2. Ethanol production from Dekkera bruxellensis in synthetic media with pentose

    Directory of Open Access Journals (Sweden)

    Carolina B. Codato

    Full Text Available Abstract Ethanol is obtained in Brazil from the fermentation of sugarcane, molasses or a mixture of these. Alternatively, it can also be obtained from products composed of cellulose and hemicellulose, called “second generation ethanol - 2G”. The yeast Saccharomyces cerevisiae, commonly applied in industrial ethanol production, is not efficient in the conversion of pentoses, which is present in high amounts in lignocellulosic materials. This study aimed to evaluate the ability of a yeast strain of Dekkera bruxellensis in producing ethanol from synthetic media, containing xylose or arabinose, xylose and glucose as the sole carbon sources. The results indicated that D. bruxellensis was capable of producing ethanol from xylose and arabinose, with ethanol concentration similar for both carbon sources, 1.9 g L-1. For the fermentations performed with xylose and glucose, there was an increase in the concentration of ethanol to 5.9 g L-1, lower than the standard yeast Pichia stipitis (9.3 g L-1, but with similar maximum yield in ethanol (0.9 g g TOC-1. This proves that the yeast D. bruxellensis produced lower amounts of ethanol when compared with P. stipitis, but showed that is capable of fermenting xylose and can be a promising alternative for ethanol conversion from hydrolysates containing glucose and xylose as carbon source.

  3. Ethanol from lignocellulosic biomasses

    International Nuclear Information System (INIS)

    Ricci, E.; Viola, E.; Zimbardi, F.; Braccio, G.; Cuna, D.

    2001-01-01

    In this report are presented results achieved on the process optimisation of bioethanol production from wheat straw, carried out within the ENEA's project of biomass exploitation for renewable energy. The process consists of three main steps: 1) biomass pretreatment by means of steam explosion; 2) enzymatic hydrolysis of the cellulose fraction; 3) fermentation of glucose. To perform the hydrolysis step, two commercial enzymatic mixtures have been employed, mainly composed by β-glucosidase (cellobiase), endo-glucanase and exo-glucanase. The ethanologenic yeast Saccharomyces cerevisiae has been used to ferment the glucose in he hydrolyzates. Hydrolysis yield of 97% has been obtained with steam exploded wheat straw treated at 220 0 C for 3 minutes and an enzyme to substrate ratio of 4%. It has been pointed out the necessity of washing with water the pretreated what straw, in order to remove the biomass degradation products, which have shown an inhibition effect on the yeast. At the best process conditions, a fermentation yield of 95% has been achieved. In the Simultaneous Saccharification and Fermentation process, a global conversion of 92% has been obtained, which corresponds to the production of about 170 grams of ethanol per kilogram of exploded straw [it

  4. Getting to Yes or Bailing on No: The Site Selection Process of Ethanol Plants in Wisconsin

    Science.gov (United States)

    Tigges, Leann M.; Noble, Molly

    2012-01-01

    Prior studies of ethanol location rest on the assumption that ethanol producers are economic free agents--evaluating sites as if all counties are contenders for their business, weighing the availability of feedstocks along with their infrastructure needs, operating without ties to localities, and being subject to enticement from policy incentives.…

  5. Physicochemical analysis of cellulose from microalgae ...

    African Journals Online (AJOL)

    USER

    2016-06-15

    Jun 15, 2016 ... The extraction method of algae cellulose was a modification of ... triplicate. Characterization of cellulose. Analysis of ... The current analysis of the cellulose extracted .... Cellulose nanomaterials review: structure, properties and.

  6. Greenprint on ethanol production in Saskatchewan

    International Nuclear Information System (INIS)

    2002-04-01

    Investment in Saskatchewan's ethanol industry is being actively promoted by the provincial government. This document represents the provincial strategy in support of the ethanol industry, which will result in significant environmental benefits for the province and the residents through the increased use of ethanol as an additive to conventional gasoline. The big advantage offered by ethanol is a more complete fuel combustion, thereby reducing emissions of greenhouse gases by as much as 30 per cent. The production costs of ethanol have decreased in the last twenty years by 50 per cent. The competitiveness of ethanol should increase due to ongoing research and development progress being made. The agricultural sector should benefit through the creation of meaningful jobs in the sector, as well as offering new marketing opportunities to the grain producers of the province and the wood-product companies. A renewable resource, ethanol reduces carbon dioxide exhaust emissions bu up to 20 per cent, reduces the smog-creating compounds up to 15 per cent, and achieves a net reduction of up to 10 per cent in carbon dioxide emissions. The abundance of raw materials and resources required for the production of ethanol, Saskatchewan possesses an obvious advantage for becoming a world leader in the field. The government of Saskatchewan has developed its strategy, outlined in this document. It calls for tax incentives, the mandating of ethanol blend, opening up markets, working with communities. The industry size, economic impact, export potential, and future opportunities were briefly discussed in the last section of the document. 1 tab., 3 figs

  7. MICROBIAL FERMENTATION OF ABUNDANT BIOPOLYMERS: CELLULOSE AND CHITIN

    Energy Technology Data Exchange (ETDEWEB)

    Leschine, Susan

    2009-10-31

    Our research has dealt with seven major areas of investigation: i) characterization of cellulolytic members of microbial consortia, with special attention recently given to Clostridium phytofermentans, a bacterium that decomposes cellulose and produces uncommonly large amounts of ethanol, ii) investigations of the chitinase system of Cellulomonas uda; including the purification and characterization of ChiA, the major component of this enzyme system, iii) molecular cloning, sequence and structural analysis of the gene that encodes ChiA in C. uda, iv) biofilm formation by C. uda on nutritive surfaces, v) investigations of the effects of humic substances on cellulose degradation by anaerobic cellulolytic microbes, vi) studies of nitrogen metabolism in cellulolytic anaerobes, and vii) understanding the molecular architecture of the multicomplex cellulase-xylanase system of Clostridium papyrosolvens. Also, progress toward completing the research of more recent projects is briefly summarized. Major accomplishments include: 1. Characterization of Clostridium phytofermentans, a cellulose-fermenting, ethanol-producing bacterium from forest soil. The characterization of a new cellulolytic species isolated from a cellulose-decomposing microbial consortium from forest soil was completed. This bacterium is remarkable for the high concentrations of ethanol produced during cellulose fermentation, typically more than twice the concentration produced by other species of cellulolytic clostridia. 2. Examination of the use of chitin as a source of carbon and nitrogen by cellulolytic microbes. We discovered that many cellulolytic anaerobes and facultative aerobes are able to use chitin as a source of both carbon and nitrogen. This major discovery expands our understanding of the biology of cellulose-fermenting bacteria and may lead to new applications for these microbes. 3. Comparative studies of the cellulase and chitinase systems of Cellulomonas uda. Results of these studies indicate

  8. On the determination of crystallinity and cellulose content in plant fibres

    DEFF Research Database (Denmark)

    Thygesen, Anders; Oddershede, Jette; Lilholt, Hans

    2005-01-01

    A comparative study of cellulose crystallinity based on the sample crystallinity and the cellulose content in plant fibres was performed for samples of different origin. Strong acid hydrolysis was found superior to agricultural fibre analysis and comprehensive plant fibre analysis for a consistent...... determination of the cellulose content. Crystallinity determinations were based on X-ray powder diffraction methods using side-loaded samples in reflection (Bragg-Brentano) mode. Rietveld refinements based on the recently published crystal structure of cellulose I beta followed by integration of the crystalline...... and 60 - 70 g/ 100 g cellulose in wood based fibres. These findings are significant in relation to strong fibre composites and bio-ethanol production....

  9. Incentives, health promotion and equality.

    Science.gov (United States)

    Voigt, Kristin

    2012-07-01

    The use of incentives to encourage individuals to adopt 'healthier' behaviours is an increasingly popular instrument in health policy. Much of the literature has been critical of 'negative' incentives, often due to concerns about equality; 'positive' incentives, however, have largely been welcomed as an instrument for the improvement of population health and possibly the reduction of health inequalities. The aim of this paper is to provide a more systematic assessment of the use of incentives from the perspective of equality. The paper begins with an overview of existing and proposed incentive schemes. I then suggest that the distinction between 'positive' and 'negative' incentives - or 'carrots' and 'sticks' - is of limited use in distinguishing those incentive schemes that raise concerns of equality from those that do not. The paper assesses incentive schemes with respect to two important considerations of equality: equality of access and equality of outcomes. While our assessment of incentive schemes will, ultimately, depend on various empirical facts, the paper aims to advance the debate by identifying some of the empirical questions we need to ask. The paper concludes by considering a number of trade-offs and caveats relevant to the assessment of incentive schemes.

  10. Ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Kolleurp, F; Daugulis, A J

    1985-05-01

    Extractive fermentation is a technique that can be used to reduce the effect of end-product inhibition through the use of a water-immiscible phase which removes fermentation products in situ. This has the beneficial effect of not only removing inhibitory products as they are formed (thus keeping reaction rates high) but also has the potential for reducing product recovery costs. We have chosen to examine the ethanol fermentation as a model system for end product inhibition and extractive fermentation, and have developed a computer model predicting the productivity enhancement possible with this technique. The model predicts an ethanol productivity of 82.6 g/L-h if a glucose feed of 750 g/L is fermented with a solvent having a distribution coefficient of 0.5 at a dilution rate of 5.0 h . This is more than 10 times higher than for a conventional chemostat fermentation of a 250 g/L glucose feed. In light of this, a systematic approach to extractive fermentation has been undertaken involving the screening of more than 1,000 solvents for their extractive properties. UNIFAC and UNIQUAC estimates of distribution coefficients and selectivities were compiled and ranked in a database, together with other important physical properties, such as density, surface tension and viscosity. Preliminary shake-flask and chemostat biocompatibility studies on the most promising solvents have been undertaken. The previous predictive, data base and experimental results are discussed.

  11. The environmental benefits of cellulosic energy crops at a landscape scale

    International Nuclear Information System (INIS)

    Graham, R.L.; Liu, W.; English, B.C.

    1995-01-01

    The objective of this paper is to present a broad overview of the potential environmental impacts of biomass energy from energy crops--particularly the cellulosic energy crops current under development. For this discussion, the term energy crop refers to a crop grown primarily to create feedstock for either making biofuels such as ethanol or burning in a heat or electricity generation facility. Cellulosic energy crops are designed to be used in cellulose-based ethanol conversion processes (as opposed to starch or sugar-based ethanol conversion processes). As more cellulose can be produced per hectare of land than can sugar or starch, the cellulose-based ethanol conversion process is a more efficient sue of land for ethanol production. Assessing the environmental impacts of biomass energy from energy crops is complex because the environmental impact of using biomass for energy must be considered in the context of alternative energy options while the environmental impact of producing biomass from energy crops must be considered in the context of alternative land-uses. Using biomass-derived energy can reduce greenhouse gas emissions or increase them; growing biomass energy crops can enhance soil fertility or degrade it. Without knowing the context of the biomass energy, one can say little about its specific environmental impacts. The primary focus of this paper is an evaluation of the environmental impacts of growing cellulosic energy crops especially at the landscape or regional scale. However, to set the stage for this discussion, the authors begin by comparing the environmental advantages and disadvantages of biomass-derived energy relative to other energy alternatives such as coal, hydropower, nuclear power, oil/gasoline, natural gas and photovoltaics

  12. Tax incentives in emerging economies

    OpenAIRE

    Brodzka, Alicja

    2013-01-01

    Emerging economies have introduced tax incentives for various reasons. In some countries in transition, such instruments may be seen as a counterweight to the investment disincentives inherent in the general tax system. In other countries, the incentives are intended to offset other disadvantages that investors may face, such as a lack of infrastructure, complicated and antiquated laws, bureaucratic complexities and weak administration. The article brings closer the issue of tax incentives of...

  13. Optimization of Deacetylation Process for Regenerated Cellulose Hollow Fiber Membranes

    Directory of Open Access Journals (Sweden)

    Xuezhong He

    2017-01-01

    Full Text Available Cellulose acetate (CA hollow fibers were spun from a CA+ Polyvinylpyrrolidone (PVP/N-methyl-2-pyrrolidone (NMP/H2O dope solution and regenerated by deacetylation. The complete deacetylation time of 0.5 h was found at a high concentration (0.2 M NaOH ethanol (96% solution. The reaction rate of deacetylation with 0.5 M NaOH was faster in a 50% ethanol compared to a 96 vol.% ethanol. The hydrogen bond between CA and tertiary amide group of PVP was confirmed. The deacetylation parameters of NaOH concentration, reaction time, swelling time, and solution were investigated by orthogonal experimental design (OED method. The degree of cross-linking, the residual acetyl content, and the PVP content in the deacetylated membranes were determined by FTIR analysis. The conjoint analysis in the Statistical Product and Service Solutions (SPSS software was used to analyze the OED results, and the importance of the deacetylation parameters was sorted as Solution > Swelling time > Reaction time > Concentration. The optimal deacetylation condition of 96 vol.% ethanol solution, swelling time 24 h, the concentration of NaOH (0.075 M, and the reaction time (2 h were identified. The regenerated cellulose hollow fibers under the optimal deacetylation condition can be further used as precursors for preparation of hollow fiber carbon membranes.

  14. Optimizing fermentation process miscanthus-to-ethanol biorefinery scale under uncertain conditions

    International Nuclear Information System (INIS)

    Bomberg, Matthew; Sanchez, Daniel L; Lipman, Timothy E

    2014-01-01

    Ethanol produced from cellulosic feedstocks has garnered significant interest for greenhouse gas abatement and energy security promotion. One outstanding question in the development of a mature cellulosic ethanol industry is the optimal scale of biorefining activities. This question is important for companies and entrepreneurs seeking to construct and operate cellulosic ethanol biorefineries as it determines the size of investment needed and the amount of feedstock for which they must contract. The question also has important implications for the nature and location of lifecycle environmental impacts from cellulosic ethanol. We use an optimization framework similar to previous studies, but add richer details by treating many of these critical parameters as random variables and incorporating a stochastic sub-model for land conversion. We then use Monte Carlo simulation to obtain a probability distribution for the optimal scale of a biorefinery using a fermentation process and miscanthus feedstock. We find a bimodal distribution with a high peak at around 10–30 MMgal yr −1 (representing circumstances where a relatively low percentage of farmers elect to participate in miscanthus cultivation) and a lower and flatter peak between 150 and 250 MMgal yr −1 (representing more typically assumed land-conversion conditions). This distribution leads to useful insights; in particular, the asymmetry of the distribution—with significantly more mass on the low side—indicates that developers of cellulosic ethanol biorefineries may wish to exercise caution in scale-up. (letters)

  15. Optimizing fermentation process miscanthus-to-ethanol biorefinery scale under uncertain conditions

    Science.gov (United States)

    Bomberg, Matthew; Sanchez, Daniel L.; Lipman, Timothy E.

    2014-05-01

    Ethanol produced from cellulosic feedstocks has garnered significant interest for greenhouse gas abatement and energy security promotion. One outstanding question in the development of a mature cellulosic ethanol industry is the optimal scale of biorefining activities. This question is important for companies and entrepreneurs seeking to construct and operate cellulosic ethanol biorefineries as it determines the size of investment needed and the amount of feedstock for which they must contract. The question also has important implications for the nature and location of lifecycle environmental impacts from cellulosic ethanol. We use an optimization framework similar to previous studies, but add richer details by treating many of these critical parameters as random variables and incorporating a stochastic sub-model for land conversion. We then use Monte Carlo simulation to obtain a probability distribution for the optimal scale of a biorefinery using a fermentation process and miscanthus feedstock. We find a bimodal distribution with a high peak at around 10-30 MMgal yr-1 (representing circumstances where a relatively low percentage of farmers elect to participate in miscanthus cultivation) and a lower and flatter peak between 150 and 250 MMgal yr-1 (representing more typically assumed land-conversion conditions). This distribution leads to useful insights; in particular, the asymmetry of the distribution—with significantly more mass on the low side—indicates that developers of cellulosic ethanol biorefineries may wish to exercise caution in scale-up.

  16. Ethanol production from alfalfa fiber fractions by saccharification and fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Sreenath, H.K. [University of Wisconsin, Madison, WI (United States). Dept. of Biological Systems Engineering; USDA Forest Service, Madison, WI (United States). Forest Products Lab.; Koegel, R.G. [US Department of Agriculture, Madison, WI (United States). Dairy Forage Research Center; Moldes, A.B. [USDA Forest Service, Madison, WI (United States). Forest Products Lab.; Universidade de Vigo, Ourense (Spain); Jeffries, T.W. [USDA Forest Service, Madison, WI (United States). Forest Products Lab.; Straub, R.J. [University of Wisconsin, Madison, WI (United States). Dept. of Biological Systems Engineering

    2001-07-01

    This work describes ethanol production from alfalfa fiber using separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) with and without liquid hot water (LHW) pretreatment. Candida shehatae FPL-702 produced 5 and 6.4 g/l ethanol with a yield of 0.25 and 0.16 g ethanol/g sugar respectively by SHF and SSF from alfalfa fiber without pretreatment. With LHW pretreatment using SSF, C. shehatae FPL-702 produced 18.0 g/l ethanol, a yield of 0.45 g ethanol/g sugar from cellulosic solids or 'raffinate'. Using SHF, it produced 9.6 g/l ethanol, a yield of 0.47 g ethanol/g sugar from raffinate. However, the soluble extract fraction containing hemicelluloses was poorly fermented in both SHF and SSF due to the presence of inhibitors. Addition of dilute acid during LHW pretreatment of alfalfa fiber resulted in fractions that were poorly saccharified and fermented. These results show that unpretreated alfalfa fiber produced a lower ethanol yield. Although LHW pretreatment can increase ethanol production from raffinate fiber fractions, it does not increase production from the hemicellulosic and pectin fractions. (author)

  17. Mutant alcohol dehydrogenase leads to improved ethanol tolerance in Clostridium thermocellum

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Steven D [ORNL; Guss, Adam M [ORNL; Karpinets, Tatiana V [ORNL; Parks, Jerry M [ORNL; Smolin, Nikolai [ORNL; Yang, Shihui [ORNL; Land, Miriam L [ORNL; Klingeman, Dawn Marie [ORNL; Bhandiwad, Ashwini [Thayer School of Engineering at Dartmouth; Rodriguez, Jr., Miguel [ORNL; Raman, Babu [Dow Chemical Company, The; Shao, Xiongjun [Thayer School of Engineering at Dartmouth; Mielenz, Jonathan R [ORNL; Smith, Jeremy C [ORNL; Keller, Martin [ORNL; Lynd, Lee R [Thayer School of Engineering at Dartmouth

    2011-01-01

    Clostridium thermocellum is a thermophilic, obligately anaerobic, Gram-positive bacterium that is a candidate microorganism for converting cellulosic biomass into ethanol through consolidated bioprocessing. Ethanol intolerance is an important metric in terms of process economics, and tolerance has often been described as a complex and likely multigenic trait for which complex gene interactions come into play. Here, we resequence the genome of an ethanol-tolerant mutant, show that the tolerant phenotype is primarily due to a mutated bifunctional acetaldehyde-CoA/alcohol dehydrogenase gene (adhE), hypothesize based on structural analysis that cofactor specificity may be affected, and confirm this hypothesis using enzyme assays. Biochemical assays confirm a complete loss of NADH-dependent activity with concomitant acquisition of NADPH-dependent activity, which likely affects electron flow in the mutant. The simplicity of the genetic basis for the ethanol-tolerant phenotype observed here informs rational engineering of mutant microbial strains for cellulosic ethanol production.

  18. Enhancement of both salivary protein-enological tannin interactions and astringency perception by ethanol.

    Science.gov (United States)

    Obreque-Slíer, Elías; Peña-Neira, Alvaro; López-Solís, Remigio

    2010-03-24

    Red wine astringency has been associated with interactions of tannins with salivary proteins. Tannins are active protein precipitants. Not much evidence exists demonstrating contribution of other wine components to astringency. We aimed to investigate an eventual role of ethanol both in astringency and salivary protein-enological tannin interactions. A trained sensory panel scored perceived astringency. Salivary protein-tannin interactions were assessed by observing both tannin-dependent changes in salivary protein diffusion on cellulose membranes and tannin-induced salivary protein precipitation. Proanthocyanidins and gallotannins in aqueous and hydroalcoholic solutions were assayed. A biphasic mode of diffusion on cellulose membranes displayed by salivary proteins was unaffected after dilution with water or enological concentrations of ethanol. At those concentrations ethanol was not astringent. In aqueous solution, tannins provoked both restriction of salivary protein diffusion, protein precipitation, and astringency. Those effects were exacerbated by 13% ethanol. In summary, enological concentrations of ethanol exacerbate astringency and salivary protein-tannin interactions.

  19. Incentives for smoking cessation.

    Science.gov (United States)

    Cahill, Kate; Hartmann-Boyce, Jamie; Perera, Rafael

    2015-05-18

    Material or financial incentives are widely used in an attempt to precipitate or reinforce behaviour change, including smoking cessation. They operate in workplaces, in clinics and hospitals, and to a lesser extent within community programmes. In this third update of our review we now include trials conducted in pregnant women, to reflect the increasing activity and resources now targeting this high-risk group of smokers. To determine whether incentives and contingency management programmes lead to higher long-term quit rates. We searched the Cochrane Tobacco Addiction Group Specialised Register, with additional searches of MEDLINE, EMBASE, CINAHL and PsycINFO. The most recent searches were in December 2014, although we also include two trials published in 2015. We considered randomised controlled trials, allocating individuals, workplaces, groups within workplaces, or communities to experimental or control conditions. We also considered controlled studies with baseline and post-intervention measures. We include studies in a mixed-population setting (e.g. community-, work-, institution-based), and also, for this update, trials in pregnant smokers. One author (KC) extracted data and a second (JH-B) checked them. We contacted study authors for additional data where necessary. The main outcome measure in the mixed-population studies was abstinence from smoking at longest follow-up, and at least six months from the start of the intervention. In the trials of pregnant smokers abstinence was measured at the longest follow-up, and at least to the end of the pregnancy. Twenty-one mixed-population studies met our inclusion criteria, covering more than 8400 participants. Ten studies were set in clinics or health centres, one in Thai villages served by community health workers, two in academic institutions, and the rest in worksites. All but six of the trials were run in the USA. The incentives included lottery tickets or prize draws, cash payments, vouchers for goods and

  20. Efficient production of ethanol from waste paper and the biochemical methane potential of stillage eluted from ethanol fermentation.

    Science.gov (United States)

    Nishimura, Hiroto; Tan, Li; Sun, Zhao-Yong; Tang, Yue-Qin; Kida, Kenji; Morimura, Shigeru

    2016-02-01

    Waste paper can serve as a feedstock for ethanol production due to being rich in cellulose and not requiring energy-intensive thermophysical pretreatment. In this study, an efficient process was developed to convert waste paper to ethanol. To accelerate enzymatic saccharification, pH of waste paper slurry was adjusted to 4.5-5.0 with H2SO4. Presaccharification and simultaneous saccharification and fermentation (PSSF) with enzyme loading of 40 FPU/g waste paper achieved an ethanol yield of 91.8% and productivity of 0.53g/(Lh) with an ethanol concentration of 32g/L. Fed-batch PSSF was used to decrease enzyme loading to 13 FPU/g waste paper by feeding two separate batches of waste paper slurry. Feeding with 20% w/w waste paper slurry increased ethanol concentration to 41.8g/L while ethanol yield decreased to 83.8%. To improve the ethanol yield, presaccharification was done prior to feeding and resulted in a higher ethanol concentration of 45.3g/L, a yield of 90.8%, and productivity of 0.54g/(Lh). Ethanol fermentation recovered 33.2% of the energy in waste paper as ethanol. The biochemical methane potential of the stillage eluted from ethanol fermentation was 270.5mL/g VTS and 73.0% of the energy in the stillage was recovered as methane. Integrating ethanol fermentation with methane fermentation, recovered a total of 80.4% of the energy in waste paper as ethanol and methane. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. The cellulose resource matrix

    NARCIS (Netherlands)

    Keijsers, E.R.P.; Yilmaz, G.; Dam, van J.E.G.

    2013-01-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where

  2. Ethanol from wood. Cellulase enzyme production

    Energy Technology Data Exchange (ETDEWEB)

    Szengyel, Zsolt

    2000-03-01

    Conversion of biomass to liquid fuels, such as ethanol, has been investigated during the past decades. First due to the oil crisis of the 1970s and lately because of concerns about greenhouse effect, ethanol has been found to be a suitable substitute for gasoline in transportation. Although ethanol is produced in large quantities from corn starch, the conversion of lignocellulosic biomass to ethanol is rather problematic. However, cellulosic raw materials are important as they are available in large quantities from agriculture and forestry. One of the most extensively investigated processes is the enzymatic process, in which fungal cellulolytic enzymes are used to convert the cellulose content of the biomass to glucose, which is then fermented to ethanol. In order to make the raw material accessible to biological attack, it has to be pretreated first. The most successful method, which has been evaluated for various lignocellulosic materials, is the steam pretreatment. In this thesis the utilization of steam pretreated willow (hardwood) and spruce (softwood) was examined for enzyme production using a filamentous fungus T. reesei RUT C30. Various carbon sources originating from the steam pretreated materials have been investigated. The replacement of the solid carbon source with a liquid carbon source, as well as the effect of pH, was studied. The effect of toxic compounds generated during pretreatment was also examined. Comparative study of softwood and hardwood showed that steam pretreated hardwood is a better carbon source than softwood. The hydrolytic potential of enzyme solutions produced on wood derived carbon sources was better compared to commercial cellulases. Also enzyme solutions produced on steam pretreated spruce showed less sensitivity towards toxic compounds formed during steam pretreatment.

  3. The potential of lignocellulosic ethanol production in the Mediterranean Basin

    Energy Technology Data Exchange (ETDEWEB)

    Faraco, Vincenza [Department of Organic Chemistry and Biochemistry, University of Naples ' ' Federico II' ' , Naples (Italy); School of Biotechnological Sciences, University of Naples ' ' Federico II' ' , Naples (Italy); Hadar, Yitzhak [Department of Microbiology and Plant Pathology, The Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot (Israel)

    2011-01-15

    This review provides an overview of the potential of bioethanol fuel production from lignocellulosic residues in the Mediterranean Basin. Residues from cereal crops, olive trees, and tomato and grape processing are abundant lignocellulosic wastes in France, Italy, Spain, Turkey and Egypt, where their use as raw materials for ethanol production could give rise to a potential production capacity of 13 Mtoe of ethanol. Due to the lack of sufficient amounts of agricultural residues in all of the other Mediterranean countries, use of the cellulosic content of municipal solid waste (MSW) as feedstock for ethanol fuel production is also proposed. A maximum potential production capacity of 30 Mtoe of ethanol could be achieved from 50% of the 180 million tons of waste currently produced annually in the Mediterranean Basin, the management of which has become a subject of serious concern. However, to make large-scale ethanol production from agricultural residues and MSW a medium-term feasible goal in the Mediterranean Basin, huge efforts are needed to achieve the required progress in cellulose ethanol technologies and to overcome several foreseeable constraints. (author)

  4. Bio ethanol production from oil palm empty fruit bunches

    International Nuclear Information System (INIS)

    Loh Soh Kheang; Muhammad Asyraf Kasim; Nasrin Abu Bakar

    2010-01-01

    Full text: The oil palm industry has an abundance of oil palm biomass. The type of biomass generated includes empty fruit bunches (EFB), oil palm trunk (OPT), kernel, shell and fronds. Generally, ligno celluloses biomass derived from oil palm has great potential to be converted into various forms of renewable energy. In this study, EFB in pulverized form was used as a feedstock for bio ethanol production. EFB contains lignin, hemicelluloses and cellulose which can be converted into fermentable sugar and bio ethanol. The EFB was initially pre-treated with 1% NaOH followed by acid hydrolysis with 0.7% sulfuric acid and enzyme prior to fermentation process with Saccharomyces cerevisea. The various process parameters for bio ethanol production was optimized i.e. pH, temperature, rate of agitation and initial feedstock concentration. The fermentation of EFB hydrolysate was at pH 4, 30 degree Celsius and 100 rpm within 72 hours of incubation yielded 10.48 g/L of bio ethanol from 50 g/L of EFB. The bio ethanol production in a 6-L bioreactor showed 36% conversion of fermentable sugar from EFB into bio ethanol. (author)

  5. Network versus Economic Incentives

    DEFF Research Database (Denmark)

    Larsen, Christian Albrekt

    The article supplements the traditional economic line of reasoning with an economic sociological account of the transition from unemployment to employment. The lack of full information is recognised by economic theory while the focus on network within the tradition of economic sociology has...... not been adopted. The article argues that the importance of network actually might be very well understood within recent economic theories that emphasise the lack of full information. The empirical evidence for the importance of network both for employed and unemployed is provided by analysing a best case...... might be an important part of the vicious circles of unemployment. Finally, the article analyse the importance of network versus the importance of economic incentives. The result supports the thesis that economic sociology provides a better account of the transition from unemployment to employment than...

  6. Recycling cellulases for cellulosic ethanol production at industrial relevant conditions

    DEFF Research Database (Denmark)

    Lindedam, Jane; Haven, Mai Østergaard; Chylenski, Piotr

    2013-01-01

    Different versions of two commercial cellulases were tested for their recyclability of enzymatic activity at high dry matter processes (12% or 25% DM). Recyclability was assessed by measuring remaining enzyme activity in fermentation broth and the ability of enzymes to hydrolyse fresh, pretreated...... to preserve enzymatic activity. Best results for enzyme recycling at 25% DM was 59% and 41% of original enzyme load for a Celluclast:Novozyme188 mixture and a modern cellulase preparation, respectively. However, issues with stability of enzymes and their strong adsorption to residual solids still pose...

  7. Anaerobic digestion as final step of a cellulosic ethanol biorefinery:

    DEFF Research Database (Denmark)

    Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2010-01-01

    ) and mesophilic (388C) operation of the UASB reactor was investigated. At an OLR of 3.5 kg- VS/(m3 day) a methane yield of 340 L/kg-VS was achieved for thermophilic operation (538C) while 270 L/kg-VS was obtained under mesophilic conditions (388C). For loading rates higher than 5 kg-VS/(m3 day) the methane yields...... of suspended matter reduced the degradation efficiency. The retention time of the anaerobic system could be reduced from 70 to 7 h by additional removal of suspended matter by clarification. Implementation of the biogas production from the fermentation effluent accounted for about 30% higher carbon utilization...

  8. Utilization of agricultural wastes for production of ethanol. Progress report, October 1979-May 1980

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.

    1980-05-01

    The project proposes to develop methods to utilize agricultural wastes, especially cottonseed hulls and peanut shells to produce ethanol. Initial steps will involve development of methods to break down cellulose to a usable form of substrates for chemical or biological digestion. The process of ethanol production will consist of (a) preparatory step to separate fibrous (cellulose) and non-fibrous (non-cellulosic compounds). The non-cellulosic residues which may include grains, fats or other substrates for alcoholic fermentation. The fibrous residues will be first pre-treated to digest cellulose with acid, alkali, and sulfur dioxide gas or other solvents. (b) The altered cellulose will be digested by suitable micro-organisms and cellulose enzymes before alcoholic fermentation. The digester and fermentative unit will be specially designed to develop a prototype for pilot plant for a continuous process. The first phase of the project will be devoted toward screening of a suitable method for cellulose modification, separation of fibrous and non-fibrous residues, the micro-organism and enzyme preparations. Work is in progress on: the effects of various microorganisms on the degree of saccharification; the effects of higher concentrations of acids, alkali, and EDTA on efficiency of microbial degradation; and the effects of chemicals on enzymatic digestion.

  9. Three-dimensional cellulose sponge: Fabrication, characterization, biomimetic mineralization, and in vitro cell infiltration.

    Science.gov (United States)

    Joshi, Mahesh Kumar; Pant, Hem Raj; Tiwari, Arjun Prasad; Maharjan, Bikendra; Liao, Nina; Kim, Han Joo; Park, Chan Hee; Kim, Cheol Sang

    2016-01-20

    In this study, cellulose based scaffolds were produced by electrospinning of cellulose acetate (CA) solution followed by its saponification with NaOH/ethanol system for 24h. The resulting nonwoven cellulose mat was treated with sodium borohydride (SB) solution. In situ hydrolysis of SB solution into the pores of the membrane produced hydrogen gas resulting a three-dimensional (3D) cellulose sponge. SEM images demonstrated an open porous and loosely packed fibrous mesh compared to the tightly packed single-layered structure of the conventional electrospun membrane. 3D cellulose sponge showed admirable ability to nucleate bioactive calcium phosphate (Ca-P) crystals in simulated body fluid (SBF) solution. SEM-EDX and X-ray diffraction studies revealed that the minerals deposited on the nanofibers have the nonstoichiometric composition similar to that of hydroxyapatite, the mineralized component of the bone. 3D cellulose sponge exhibited the better cell infiltration, spreading and proliferation compared to 2D cellulose mat. Therefore, a facile fabrication of 3D cellulose sponge with improved mineralization represents an innovative strategy for the bone tissue engineering applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Process for producing ethanol from plant biomass using the fungus Paecilomyces sp

    Science.gov (United States)

    Wu, J.F.

    1985-08-08

    A process for producing ethanol from plant biomass is disclosed. The process includes forming a substrate from the biomass with the substrate including hydrolysates of cellulose and hemicellulose. A species of the fungus Paecilomyces which has the ability to ferment both cellobiose and xylose to ethanol is then selected and isolated. The substrate is inoculated with this fungus, and the inoculated substrate is then fermented under conditions favorable for cell viability and conversion of hydrolysates to ethanol. Finally, ethanol is recovered from the fermented substrate. 5 figs., 3 tabs.

  11. Genome-Wide Association Study Reveals Novel Genes Associated with Culm Cellulose Content in Bread Wheat (Triticum aestivum, L.

    Directory of Open Access Journals (Sweden)

    Simerjeet Kaur

    2017-11-01

    Full Text Available Plant cell wall formation is a complex, coordinated and developmentally regulated process. Cellulose is the most dominant constituent of plant cell walls. Because of its paracrystalline structure, cellulose is the main determinant of mechanical strength of plant tissues. As the most abundant polysaccharide on earth, it is also the focus of cellulosic biofuel industry. To reduce culm lodging in wheat and for improved ethanol production, delineation of the variation for stem cellulose content could prove useful. We present results on the analysis of the stem cellulose content of 288 diverse wheat accessions and its genome-wide association study (GWAS. Cellulose concentration ranged from 35 to 52% (w/w. Cellulose content was normally distributed in the accessions around a mean and median of 45% (w/w. Genome-wide marker-trait association study using 21,073 SNPs helped identify nine SNPs that were associated (p < 1E-05 with cellulose content. Four strongly associated (p < 8.17E-05 SNP markers were linked to wheat unigenes, which included β-tubulin, Auxin-induced protein 5NG4, and a putative transmembrane protein of unknown function. These genes may be directly or indirectly involved in the formation of cellulose in wheat culms. GWAS results from this study have the potential for genetic manipulation of cellulose content in bread wheat and other small grain cereals to enhance culm strength and improve biofuel production.

  12. Internal and External Barriers Impacting Non-Food Cellulosic Biofuel Projects in the United States

    Directory of Open Access Journals (Sweden)

    Jeremy Withers

    2015-05-01

    Full Text Available Escalating demand, along with EPAct 2005, has led the United States government to assume a twofold leadership approach of energy security and environmental practices. This has initiated several important issues pertaining to cellulosic biofuel production. However, little is known about what is needed for the U.S. to lead long-term renewable energy security, how the US will develop and implement leading environmental energy practices, what supply capabilities and refining technologies are available to produce renewable fuels, and how funding can be used to adopt available technologies. This article examines geographical aspects, operational status, and barriers tending to prevent the successful commercialization of non-food cellulosic ethanol projects in the U.S. from secondary sources. Outcomes of this research can be used to further understand inhibitors that impact the production and commercialization of ethanol from non-food cellulosic sources.

  13. Ethanol production from rape straw: Part of an oilseed rape biorefinery

    DEFF Research Database (Denmark)

    Arvaniti, Efthalia

    The aim of this study was 1) present an oilseed rape whole crop biorefinery; 2) to investigate the best available experimental conditions for production of cellulosic ethanol from rape straw, and included the processes of thermo-chemical pretreatment, enzymatic hydrolysis, and C6 fermentation......, and 3) to couple cellulosic ethanol production to production of cellulolytic enzymes that are needed for cellulosic ethanol production, inside a rape straw biorefinery. For the first is based less on available experiments, and more on literature review. The second and third study conclusions were drawn...... rapeseed biodiesel plant of Europe to an oilseed rape whole-crop biorefinery by 2020 is envisioned and discussed. The description and discussion of this biorefinery is based partly on literature review, and partly on own experimental data, especially on pretreatment of rape straw, and production...

  14. Synthesis and characterization of cellulose derivatives obtained from bacterial cellulose

    International Nuclear Information System (INIS)

    Oliveira, Rafael L. de; Barud, Hernane; Ribeiro, Sidney J.L.; Messaddeq, Younes

    2011-01-01

    The chemical modification of cellulose leads to production of derivatives with different properties from those observed for the original cellulose, for example, increased solubility in more traditional solvents. In this work we synthesized four derivatives of cellulose: microcrystalline cellulose, cellulose acetate, methylcellulose and carboxymethylcellulose using bacterial cellulose as a source. These were characterized in terms of chemical and structural changes by examining the degree of substitution (DS), infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy - NMR 13 C. The molecular weight and degree of polymerization were evaluated by viscometry. The characterization of the morphology of materials and thermal properties were performed with the techniques of X-ray diffraction, electron microscopy images, differential scanning calorimetry (DSC) and thermogravimetric analysis. (author)

  15. Glucose production for cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, S; Karube, I

    1977-04-16

    Glucose was produced from cellulose by passing a cellulose solution through a column of an immobilized cellulase which was prepared by coating an inorganic carrier such as macadam or stainless steel beads with collagen containing the cellulase. Thus, 4 mL of 5% cellulase T-AP (60,000 units/g) solution was dissolved in 100 g of 0.9% collagen solution and the solution mixed with 60 g of macadam (diam. = 0.5 to 1.5 mm) and stirred for 10 min. The treated beads were dried in air at 10/sup 0/ to yield an immobilized enzyme retaining 64% of its activity. Through a column (0.8 x 20 cm) packed with 3 g of the immobilized enzyme, 100 mL of 0.33% Avicel SF solution was circulated at 26.4 mL/min at 30/sup 0/ for 60 h. The Avicel SF conversion to glucose was 23%.

  16. High Performance Regenerated Cellulose Membranes from Trimethylsilyl Cellulose

    KAUST Repository

    Ali, Ola

    2013-01-01

    Regenerated cellulose (RC) membranes are extensively used in medical and pharmaceutical separation processes due to their biocompatibility, low fouling tendency and solvent resistant properties. They typically possess ultrafiltration

  17. Production of Biofuels from Selected Cellulosic Waste materials

    Directory of Open Access Journals (Sweden)

    Jathwa Abdul Kareem Ibrahim

    2017-08-01

    Full Text Available In this study four types of cellulose-rich municipal solid wastes (residuals of orange, banana peel, corn residues, and saw dust were used as raw materials. These cellulosic substrates usually have a lot of lignin content which prevents the process of saccharification by microorganisms. Thus pretreatment methods of enzymatic, acid or base with enzymatic treatment and dilute acid followed by autoclaving were necessary to dignify these wastes and to obtain higher reducing sugar yields and hence higher ethanol production. Dilute HCl acid of 1% followed by autoclaving at 121℃ for 30 min proved to give good result where significant amounts of reducing sugars were obtained at the end of the saccharification process. Orange peel proved to give the highest glucose concentration of an average of 6000 mg/l on day 4 of the saccharification process. Fermentation was carried out for the hydrolyzed samples using Saccharomyces cerevisiae yeast. The amount of ethanol produced after fermentation was found to be the highest for orange peel having a value of 1300 mg/l after 96h of incubation. As science is proceeding, engineered microorganisms could help to produce sustainable fuels from cellulose-rich municipal solid wastes in the future.

  18. One-pot bioethanol production from cellulose by co-culture of Acremonium cellulolyticus and Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Park Enoch Y

    2012-08-01

    Full Text Available Abstract Background While the ethanol production from biomass by consolidated bioprocess (CBP is considered to be the most ideal process, simultaneous saccharification and fermentation (SSF is the most appropriate strategy in practice. In this study, one-pot bioethanol production, including cellulase production, saccharification of cellulose, and ethanol production, was investigated for the conversion of biomass to biofuel by co-culture of two different microorganisms such as a hyper cellulase producer, Acremonium cellulolyticus C-1 and an ethanol producer Saccharomyces cerevisiae. Furthermore, the operational conditions of the one-pot process were evaluated for maximizing ethanol concentration from cellulose in a single reactor. Results Ethanol production from cellulose was carried out in one-pot bioethanol production process. A. cellulolyticus C-1 and S. cerevisiae were co-cultured in a single reactor. Cellulase producing-medium supplemented with 2.5 g/l of yeast extract was used for productions of both cellulase and ethanol. Cellulase production was achieved by A. cellulolyticus C-1 using Solka-Floc (SF as a cellulase-inducing substrate. Subsequently, ethanol was produced with addition of both 10%(v/v of S. cerevisiae inoculum and SF at the culture time of 60 h. Dissolved oxygen levels were adjusted at higher than 20% during cellulase producing phase and at lower than 10% during ethanol producing phase. Cellulase activity remained 8–12 FPU/ml throughout the one-pot process. When 50–300 g SF/l was used in 500 ml Erlenmeyer flask scale, the ethanol concentration and yield based on initial SF were as 8.7–46.3 g/l and 0.15–0.18 (g ethanol/g SF, respectively. In 3-l fermentor with 50–300 g SF/l, the ethanol concentration and yield were 9.5–35.1 g/l with their yields of 0.12–0.19 (g/g respectively, demonstrating that the one-pot bioethanol production is a reproducible process in a scale-up bioconversion of cellulose to ethanol

  19. PEI detoxification of pretreated spruce for high solids ethanol fermentation

    DEFF Research Database (Denmark)

    Cannella, David; Sveding, Per Viktor; Jørgensen, Henning

    2014-01-01

    .e. spruce) this has been difficult to reach. The main reason behind this difference is the higher recalcitrance of woody substrates which require harsher pretreatment conditions, thus generating higher amounts of inhibitory compounds, ultimately lowering fermentation performances. In this work we studied...... ethanol production from spruce performing the whole process, from pretreatment to hydrolysis and fermentation, at 30% dry matter (equivalent to similar to 20% WIS). Hydrolysis and fermentation was performed in a horizontal free fall mixing reactor enabling efficient mixing at high solids loadings....... In batch simultaneous saccharification and fermentation (SSF), up to 76% cellulose to ethanol conversion was achieved resulting in a concentration of 51 g/kg of ethanol. Key to obtaining this high ethanol yield at these conditions was the use of a detoxification technology based on applying a soluble...

  20. Detoxification and fermentation of pyrolytic sugar for ethanol production.

    Science.gov (United States)

    Wang, Hui; Livingston, Darrell; Srinivasan, Radhakrishnan; Li, Qi; Steele, Philip; Yu, Fei

    2012-11-01

    The sugars present in bio-oil produced by fast pyrolysis can potentially be fermented by microbial organisms to produce cellulosic ethanol. This study shows the potential for microbial digestion of the aqueous fraction of bio-oil in an enrichment medium to consume glucose and produce ethanol. In addition to glucose, inhibitors such as furans and phenols are present in the bio-oil. A pure glucose enrichment medium of 20 g/l was used as a standard to compare with glucose and aqueous fraction mixtures for digestion. Thirty percent by volume of aqueous fraction in media was the maximum additive amount that could be consumed and converted to ethanol. Inhibitors were removed by extraction, activated carbon, air stripping, and microbial methods. After economic analysis, the cost of ethanol using an inexpensive fermentation medium in a large scale plant is approximately $14 per gallon.

  1. U.S. Army Incentive Program: Incentives That Motivate Recruiters

    National Research Council Canada - National Science Library

    Starkey, Benjamin

    1999-01-01

    .... Sixty recruiters and staff personnel at the brigade, battalion and company echelons were randomly selected and interviewed on how the various national and local incentives motivate recruiters to meet...

  2. TECHNOLOGICAL ADVANCES IN THE OBTAINING OF ETHANOL FROM Sweet sorghum (Sorghum bicolor (L. Moench

    Directory of Open Access Journals (Sweden)

    Sandro Pedroso Cunha

    2010-11-01

    Full Text Available ABSTRACT: Replacing the use of gasoline with ethanol in vehicles reduces by 90% CO2 emissions, this justifies the interest in the use of bioethanol as renewable energy. Besides sugar cane, cassava, maize and sugar beet special emphasis is being given to sorghum (Sorghum bicolor L. Moench to produce ethanol for its productivity and resistance. The sorghum is grown in Rio Grande do Sul with a production of about 70,000 tons / year. Embrapa has a program to develop cultivars of sorghum from the time the Pro-Alcohol and currently 25 new varieties of sorghum are being evaluated. Several factors are relevant in the optimization of production such as increased productivity and reduced costs in the production of ethanol. This study aimed to survey recent data that will assess production parameters of ethanol from sorghum. Factors such as reducing the risk of bacterial contamination, the means conducive to fermentation processes or grain sorghum stalk through the use of pretreatment of the sample, have been of great importance because it is basically turning cellulosic biomass into fermentable sugars. Superior genotypes of sweet sorghum for ethanol production are of utmost importance, as well as better ways to convert sugars into ethanol. Lignin, toxic against microorganisms, prevents the conversion of lignocellulose into ethanol. The conversion of lignocellulosic ethanol compounds based on the hydrolysis of cellulose producing simple sugars and fermenting those sugars into ethanol through microbiology.

  3. An Investigation of Cellulose Digesting Bacteria in the Panda Gut Microbiome

    Science.gov (United States)

    Lu, M.; Leung, F. C.

    2014-12-01

    The Giant Panda (Ailuropoda melanoleuca) diet consists primarily of bamboo leaves, stems and shoots. However, the Giant Panda lacks genes for the enzymes needed to digest cellulose, the core component of bamboo. Thus, it is hypothesized that the cellulolytic digestion necessary for maintaining the Giant Panda diet is carried out by microbial symbionts in the panda gut microbiota. Fecal microbiota is used as surrogate index for gut microbiota since the Giant Panda is listed by the World Conservation Union as a Threatened Species. Two bacterial isolates with potential cellulolytic activity were isolated from Giant Panda fecal samples and cultured on selective media CMC (carboxymethyl cellulose) agar and CMC-Congo Red agar using various methods of inoculation. After incubation, clearance zones around colonies were observed and used as qualitative assays for cellulose digestion. Polymerase chain reaction amplification of the 16S rRNA gene was completed and species identification was done based on the BLAST result of 16S rRNA sequence obtained using Sanger sequencing. Once the cellulase activity is confirmed, genomic DNA of the bacteria will be extracted and used for whole genome shotgun sequencing. Illumina next generation sequencing platform will be adopted as it yields high-throughput information, providing a better understanding of cellulose digestion and the molecular genetic pathways to renewable sources of biofuels. Researchers have identified multiple cellulose-digesting microbes in the Giant Panda gut, but few have applied such bacteria in converting cellulose into glucose to create biofuel. Cellulosic ethanol, a biofuel, is produced through the fermentation of lignocellulosic biomasses. This anaerobic process is aided by cellulose-digesting enzymes. Certain microbes, such as those present in the Giant Panda gut, can produce enzymes that cleave the glycosidic bonds of cellulose (C6H10O5) into glucose molecules (C6H12O6), which can then be fermented into ethanol

  4. Wet oxidation pretreatment of rape straw for ethanol production

    International Nuclear Information System (INIS)

    Arvaniti, Efthalia; Bjerre, Anne Belinda; Schmidt, Jens Ejbye

    2012-01-01

    Rape straw can be used for production of second generation bioethanol. In this paper we optimized the pretreatment of rape straw for this purpose using Wet oxidation (WO). The effect of reaction temperature, reaction time, and oxygen gas pressure was investigated for maximum ethanol yield via Simultaneous Saccharification and Fermentation (SSF). To reduce the water use and increase the energy efficiency in WO pretreatment features like recycling liquid (filtrate), presoaking of rape straw in water or recycled filtrate before WO, skip washing pretreated solids (filter cake) after WO, or use of whole slurry (Filter cake + filtrate) in SSF were also tested. Except ethanol yields, pretreatment methods were evaluated based on achieved glucose yields, amount of water used, recovery of cellulose, hemicellulose, and lignin. The highest ethanol yield obtained was 67% after fermenting the whole slurry produced by WO at 205 °C for 3 min with 12 bar of oxygen gas pressure and featured with presoaking in water. At these conditions after pre-treatment, cellulose and hemicellulose was recovered quantitatively (100%) together with 86% of the lignin. WO treatments of 2–3 min at 205–210 °C with 12 bar of oxygen gas produced higher ethanol yields and cellulose, hemicelluloses, and lignin recoveries, than 15 min WO treatment at 195 °C. Also, recycling filtrate and use of higher oxygen gas pressure reduced recovery of materials. The use of filtrate could be inhibitory for the yeast, but also reduced lactic acid formation in SSF. -- Highlights: ► Wet Oxidation pretreatment on rape straw for sugar and ethanol production. ► Variables were reaction time, temperature, and oxygen gas pressure. ► Also, other configurations for increase of water and energy efficiency. ► Short Wet oxidation pretreatment (2–3 min) produced highest ethanol yield. ► After these pretreatment conditions recovery of lignin in solids was 86%.

  5. Premier Hospital Quality Incentive Demonstration

    Data.gov (United States)

    U.S. Department of Health & Human Services — CMS is pursuing a vision to improve the quality of health care by expanding the information available about quality of care and through direct incentives to reward...

  6. Sugar-Based Ethanol Biorefinery: Ethanol, Succinic Acid and By-Product Production

    Energy Technology Data Exchange (ETDEWEB)

    Donal F. Day

    2009-03-31

    The work conducted in this project is an extension of the developments itemized in DE-FG-36-04GO14236. This program is designed to help the development of a biorefinery based around a raw sugar mill, which in Louisiana is an underutilized asset. Some technical questions were answered regarding the addition of a biomass to ethanol facility to existing sugar mills. The focus of this work is on developing technology to produce ethanol and valuable by-products from bagasse. Three major areas are addressed, feedstock storage, potential by-products and the technology for producing ethanol from dilute ammonia pre-treated bagasse. Sugar mills normally store bagasse in a simple pile. During the off season there is a natural degradation of the bagasse, due to the composting action of microorganisms in the pile. This has serious implications if bagasse must be stored to operate a bagasse/biorefinery for a 300+ day operating cycle. Deterioration of the fermentables in bagasse was found to be 6.5% per month, on pile storage. This indicates that long term storage of adequate amounts of bagasse for year-round operation is probably not feasible. Lignin from pretreatment seemed to offer a potential source of valuable by-products. Although a wide range of phenolic compounds were present in the effluent from dilute ammonia pretreatment, the concentrations of each (except for benzoic acid) were too low to consider for extraction. The cellulosic hydrolysis system was modified to produce commercially recoverable quantities of cellobiose, which has a small but growing market in the food process industries. A spin-off of this led to the production of a specific oligosaccharide which appears to have both medical and commercial implications as a fungal growth inhibitor. An alternate use of sugars produced from biomass hydrolysis would be to produce succinic acid as a chemical feedstock for other conversions. An organism was developed which can do this bioconversion, but the economics of

  7. Incentive contracts and time use

    OpenAIRE

    Tor Viking Eriksson; Jaime Ortega

    2011-01-01

    Empirical studies on incentive contracts have primarily been concerned with the effects on employees’ productivity and earnings. The productivity increases associated with such contracts may, however, come at the expense of quality of life at or outside work. In this paper we study the effect on the employees’ non-work activities, testing whether incentive contracts lead to a change in the allocation of time across work and non-work activities. In doing so, we distinguish between two effects,...

  8. Drug-loaded Cellulose Acetate and Cellulose Acetate Butyrate Films ...

    African Journals Online (AJOL)

    The purpose of this research work was to evaluate the contribution of formulation variables on release properties of matrix type ocular films containing chloramphenicol as a model drug. This study investigated the use of cellulose acetate and cellulose acetate butyrate as film-forming agents in development of ocular films.

  9. An Investigation of Cellulose Digesting Bacteria in the Camel Feces Microbiome

    Science.gov (United States)

    Man, V.; Leung, F. C.

    2015-12-01

    Research Question: Is there a bacteria in camel feces that digests cellulose material and can be used for waste to energy projects? Fossil fuels are the current main resource of energy in the modern world. However, as the demand for fuel increases, biofuels have been proposed as an alternative energy source that is a more sustainable form of liquid fuel generation from living things or waste, commonly known as biofuels and ethanol. The Camelus dromedarius', also known as Arabian camel, diet consist of grass, grains, wheat and oats as well desert vegetation in their natural habitat. However, as the Arabian camel lacks the enzymes to degrade cellulose, it is hypothesized that cellulose digestion is performed by microbial symbionts in camel microbiota. Fecal samples were collected from the Camelus dromedarius in United Arab Emirates and diluted 10-7 times. The diluted sample was then streaked onto a Sodium Carboxymethyl Cellulose plate, and inoculated onto CMC and Azure-B plates. Afterwards, Congo Red was used for staining in order to identify clearance zones of single colonies that may potentially be used as a qualitative assays for cellulose digestion. Then the colonies undergo polymerase chain reaction amplification to produce amplified RNA fragments. The 16S ribosomal RNA gene is identified based on BLAST result using Sanger Sequencing. Amongst the three identified microbes: Bacillus, Staphylococcus and Escherichia coli, both Bacillus and Staphylococcus are cellulose-digesting microbes, and through the fermentation of lignocellulosic, biomasses can be converted into cellulosic ethanol (Biofuel). According to the Improvements in Life Cycle Energy Efficiency and Greenhouse Gas Emissions of Corn-Ethanol by Adam J. Liska, ""Ethanol reduces greenhouse gas emissions by 40-50% when compared directly to gasoline." The determination of bacterial communities that are capable of efficiently and effectively digesting cellulose materials requires that the bacteria be first

  10. Microbial fuel cell treatment of ethanol fermentation process water

    Science.gov (United States)

    Borole, Abhijeet P [Knoxville, TN

    2012-06-05

    The present invention relates to a method for removing inhibitor compounds from a cellulosic biomass-to-ethanol process which includes a pretreatment step of raw cellulosic biomass material and the production of fermentation process water after production and removal of ethanol from a fermentation step, the method comprising contacting said fermentation process water with an anode of a microbial fuel cell, said anode containing microbes thereon which oxidatively degrade one or more of said inhibitor compounds while producing electrical energy or hydrogen from said oxidative degradation, and wherein said anode is in electrical communication with a cathode, and a porous material (such as a porous or cation-permeable membrane) separates said anode and cathode.

  11. Ethanol Basics (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2015-01-01

    Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.

  12. Radiation degradation of cellulose

    International Nuclear Information System (INIS)

    Leonhardt, J.; Arnold, G.; Baer, M.; Langguth, H.; Gey, M.; Huebert, S.

    1985-01-01

    The application of straw and other cellulose polymers as feedstuff for ruminants is limited by its low digestibility. During recent decades it was attempted to increase the digestibility of straw by several chemical and physical methods. In this work some results of the degradation of gamma and electron treated wheat straw are reported. Complex methods of treatment are taken into consideration. In vitro-experiments with radiation treated straw show that the digestibility can be increased from 20% up to about 80%. A high pressure liquid chromatography method was used to analyze the hydrolysates. The contents of certain species of carbohydrates in the hydrolysates in dependence on the applied dose are given. (author)

  13. Cellulose gels produced in room temperature ionic liquids by ionizing radiation

    International Nuclear Information System (INIS)

    Kimura, Atsushi; Nagasawa, Naotsugu; Taguchi, Mitsumasa

    2014-01-01

    Cellulose-based gels were produced in room temperature ionic liquids (RTILs) by ionizing radiation. Cellulose was dissolved at the initial concentration of 20 wt% in 1-ethyl-3-methylimidazolium (EMI)-acetate or N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium (DEMA)-formate with a water content of 18 wt%, and irradiated with γ-rays under aerated condition to produce new cellulose gels. The gel fractions of the cellulose gels obtained in EMI-acetate and DEMA-formate at a dose of 10 kGy were 13% and 19%, respectively. The formation of gel fractions was found to depend on the initial concentration of cellulose, water content, and irradiation temperature. The obtained gel readily absorbed water, methanol, ethanol, dichloromethane, N,N-dimethylacetamide, and RTILs. - Highlights: • Cellulose gels were produced in room temperature ionic liquids (RTILs). • Water plays a crucial role in the cross-linking reaction. • Cellulose gels swollen with RTILs show good electronic conductivity (3.0 mS cm −1 )

  14. Cellulose synthase complex organization and cellulose microfibril structure.

    Science.gov (United States)

    Turner, Simon; Kumar, Manoj

    2018-02-13

    Cellulose consists of linear chains of β-1,4-linked glucose units, which are synthesized by the cellulose synthase complex (CSC). In plants, these chains associate in an ordered manner to form the cellulose microfibrils. Both the CSC and the local environment in which the individual chains coalesce to form the cellulose microfibril determine the structure and the unique physical properties of the microfibril. There are several recent reviews that cover many aspects of cellulose biosynthesis, which include trafficking of the complex to the plasma membrane and the relationship between the movement of the CSC and the underlying cortical microtubules (Bringmann et al. 2012 Trends Plant Sci. 17 , 666-674 (doi:10.1016/j.tplants.2012.06.003); Kumar & Turner 2015 Phytochemistry 112 , 91-99 (doi:10.1016/j.phytochem.2014.07.009); Schneider et al. 2016 Curr. Opin. Plant Biol. 34 , 9-16 (doi:10.1016/j.pbi.2016.07.007)). In this review, we will focus on recent advances in cellulose biosynthesis in plants, with an emphasis on our current understanding of the structure of individual catalytic subunits together with the local membrane environment where cellulose synthesis occurs. We will attempt to relate this information to our current knowledge of the structure of the cellulose microfibril and propose a model in which variations in the structure of the CSC have important implications for the structure of the cellulose microfibril produced.This article is part of a discussion meeting issue 'New horizons for cellulose nanotechnology'. © 2017 The Author(s).

  15. Cellulose binding domain fusion proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc A.; Doi, Roy H.

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  16. Production of ethanol from sugars and lignocellulosic biomass by Thermoanaerobacter J1 isolated from a hot spring in Iceland.

    Science.gov (United States)

    Jessen, Jan Eric; Orlygsson, Johann

    2012-01-01

    Thermophilic bacteria have gained increased attention as candidates for bioethanol production from lignocellulosic biomass. This study investigated ethanol production by Thermoanaerobacter strain J1 from hydrolysates made from lignocellulosic biomass in batch cultures. The effect of increased initial glucose concentration and the partial pressure of hydrogen on end product formation were examined. The strain showed a broad substrate spectrum, and high ethanol yields were observed on glucose (1.70 mol/mol) and xylose (1.25 mol/mol). Ethanol yields were, however, dramatically lowered by adding thiosulfate or by cocultivating strain J1 with a hydrogenotrophic methanogen with acetate becoming the major end product. Ethanol production from 4.5 g/L of lignocellulosic biomass hydrolysates (grass, hemp stem, wheat straw, newspaper, and cellulose) pretreated with acid or alkali and the enzymes Celluclast and Novozymes 188 was investigated. The highest ethanol yields were obtained on cellulose (7.5 mM·g(-1)) but the lowest on straw (0.8 mM·g(-1)). Chemical pretreatment increased ethanol yields substantially from lignocellulosic biomass but not from cellulose. The largest increase was on straw hydrolysates where ethanol production increased from 0.8 mM·g(-1) to 3.3 mM·g(-1) using alkali-pretreated biomass. The highest ethanol yields on lignocellulosic hydrolysates were observed with hemp hydrolysates pretreated with acid, 4.2 mM·g(-1).

  17. Production of Ethanol from Sugars and Lignocellulosic Biomass by Thermoanaerobacter J1 Isolated from a Hot Spring in Iceland

    Directory of Open Access Journals (Sweden)

    Jan Eric Jessen

    2012-01-01

    Full Text Available Thermophilic bacteria have gained increased attention as candidates for bioethanol production from lignocellulosic biomass. This study investigated ethanol production by Thermoanaerobacter strain J1 from hydrolysates made from lignocellulosic biomass in batch cultures. The effect of increased initial glucose concentration and the partial pressure of hydrogen on end product formation were examined. The strain showed a broad substrate spectrum, and high ethanol yields were observed on glucose (1.70 mol/mol and xylose (1.25 mol/mol. Ethanol yields were, however, dramatically lowered by adding thiosulfate or by cocultivating strain J1 with a hydrogenotrophic methanogen with acetate becoming the major end product. Ethanol production from 4.5 g/L of lignocellulosic biomass hydrolysates (grass, hemp stem, wheat straw, newspaper, and cellulose pretreated with acid or alkali and the enzymes Celluclast and Novozymes 188 was investigated. The highest ethanol yields were obtained on cellulose (7.5 mM·g−1 but the lowest on straw (0.8 mM·g−1. Chemical pretreatment increased ethanol yields substantially from lignocellulosic biomass but not from cellulose. The largest increase was on straw hydrolysates where ethanol production increased from 0.8 mM·g−1 to 3.3 mM·g−1 using alkali-pretreated biomass. The highest ethanol yields on lignocellulosic hydrolysates were observed with hemp hydrolysates pretreated with acid, 4.2 mM·g−1.

  18. Saccharification of cellulose by acetolysis

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T; Yamanaka, S; Takinami, K

    1978-01-01

    For saccharification of cellulose, an acetolysis method using assimilable acid with a microorganism was applied. Based on this method, a new method which gave totally assimilable products was established. The rigid crystalline structure of cellulose was disrupted by acetolysis with 2-2.5 times as much acetic anhydride as cellulose on a weight basis and 1 N sulfuric acid as a catalyst. Then for cleavage of O-acetyl ester and glycosidic bonds, the resulting amorphous acetolysate of cellulose could easily be hydrolyzed by heating in 1 N sulfuric acid at 120/sup 0/C for 1-1.5 h without over-disruption of glucose. Ninety-eight % of the cellulose used was recovered in the form of hydrolysate having about 30% saccharide concentration. The hydrolysate obtained was composed of 74% glucose, 13% cellobiose and 11% mono-O-acetyl glucose on a weight basis.

  19. The preparation and ethanol fermentation of high-concentration sugars from steam-explosion corn stover.

    Science.gov (United States)

    Xie, Hui; Wang, Fengqin; Yin, Shuangyao; Ren, Tianbao; Song, Andong

    2015-05-01

    In the field of biofuel ethanol, high-concentration- reducing sugars made from cellulosic materials lay the foundation for high-concentration ethanol fermentation. In this study, corn stover was pre-treated in a process combining chemical methods and steam explosion; the cellulosic hydrolyzed sugars obtained by fed-batch saccharification were then used as the carbon source for high-concentration ethanol fermentation. Saccharomyces cerevisiae 1308, Angel yeast, and Issatchenkia orientalis were shake-cultured with Pachysolen tannophilus P-01 for fermentation. Results implied that the ethanol yields from the three types of mixed strains were 4.85 g/100 mL, 4.57 g/100 mL, and 5.02 g/100 mL (separately) at yield rates of 91.6, 89.3, and 92.2%, respectively. Therefore, it was inferred that shock-fermentation using mixed strains achieved a higher ethanol yield at a greater rate in a shorter fermentation period. This study provided a theoretical basis and technical guidance for the fermentation of industrial high-concentrated cellulosic ethanol.

  20. Ethanol production of banana shell and cassava starch

    International Nuclear Information System (INIS)

    Monsalve G, John F; Medina de Perez, Victoria Isabel; Ruiz colorado, Angela Adriana

    2006-01-01

    In this work the acid hydrolysis of the starch was evaluated in cassava and the cellulose shell banana and its later fermentation to ethanol, the means of fermentation were adjusted for the microorganisms saccharomyces cerevisiae nrrl y-2034 and zymomonas mobilis cp4. The banana shell has been characterized, which possesses a content of starch, cellulose and hemicelluloses that represent more than 80% of the shell deserve the study of this as source of carbon. The acid hydrolysis of the banana shell yield 20g/l reducing sugar was obtained as maximum concentration. For the cassava with 170 g/l of starch to ph 0.8 in 5 hours complete conversion is achieved to you reducing sugars and any inhibitory effect is not noticed on the part of the cultivations carried out with banana shell and cassava by the cyanide presence in the cassava and for the formation of toxic compounds in the acid hydrolysis the cellulose in banana shell. For the fermentation carried out with saccharomyces cerevisiae a concentration of ethanol of 7.92± 0.31% it is achieved and a considerable production of ethanol is not appreciated (smaller than 0.1 g/l) for none of the means fermented with zymomonas mobilis

  1. Valuing climate protection through willingness to pay for biomass ethanol

    International Nuclear Information System (INIS)

    Solomon, Barry D.; Johnson, Nicholas H.

    2009-01-01

    This study uses a multi-part, split-sample contingent valuation method (CVM) and fair share (FS) survey to better understand the public's valuation of mitigating global climate change through its willingness to pay for biomass or 'cellulosic' ethanol. In addition to a basic CVM question, a related scenario was developed that asked half of the survey respondents to state their fair share cost to lessen a potential food shortage in the next decade, also through the expanded use of cellulosic ethanol. Three alternative biomass feedstocks were assessed: farming residues, forestry residues and paper mill wastes, and municipal solid wastes. Overall a slightly larger proportion of respondents were WTP extra for cellulosic ethanol in the basic CVM scenario than in the FS scenario, though no significant differences were found in the WTP for the different feedstocks. Bid curve lognormal regression results for the two models were similar, supporting the idea that asking a FS rather than a conventional WTP question may be justifiable in some circumstances, such as in cases of a national emergency. (author)

  2. Approaching zero cellulose loss in cellulose nanocrystal (CNC) production: recovery and characterization of cellulosic solid residues (CSR) and CNC

    Science.gov (United States)

    Q.Q. Wang; J.Y. Zhu; R.S. Reiner; S.P. Verrill; U. Baxa; S.E. McNeil

    2012-01-01

    This study demonstrated the potential of simultaneously recovering cellulosic solid residues (CSR) and producing cellulose nanocrystals (CNCs) by strong sulfuric acid hydrolysis to minimize cellulose loss to near zero. A set of slightly milder acid hydrolysis conditions than that considered as “optimal” were used to significantly minimize the degradation of cellulose...

  3. Incentives to promote family planning.

    Science.gov (United States)

    Heil, Sarah H; Gaalema, Diann E; Herrmann, Evan S

    2012-11-01

    Over the past 60 years, population control has become an increasingly urgent issue worldwide as a growing population strains already limited resources. The use of financial incentives to promote family planning is an innovative approach that has potential to make a contribution to efforts to better manage population growth. This report reviews eight studies that examined the effect of incentives on family planning. Published studies that tested the impact of incentives to promote some aspect of family planning and included an appropriate control or comparison condition were reviewed. Incentives have been used to promote attendance at contraceptive education sessions, adoption and continuation of contraceptive methods, sterilization, and to limit family size. All but one of the eight studies reviewed reported positive outcomes, but weaknesses in study design and execution limit the strength of the conclusions that can be drawn. Review of this literature suggests that family planning behaviors, like other behaviors, are sensitive to incentives. Given the tremendous need for efficacious interventions in global efforts to manage population growth, further research on this topic using more rigorous experimental methods is warranted. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. NREL 2012 Achievement of Ethanol Cost Targets: Biochemical Ethanol Fermentation via Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Tao, L.; Schell, D.; Davis, R.; Tan, E.; Elander, R.; Bratis, A.

    2014-04-01

    For the DOE Bioenergy Technologies Office, the annual State of Technology (SOT) assessment is an essential activity for quantifying the benefits of biochemical platform research. This assessment has historically allowed the impact of research progress achieved through targeted Bioenergy Technologies Office funding to be quantified in terms of economic improvements within the context of a fully integrated cellulosic ethanol production process. As such, progress toward the ultimate 2012 goal of demonstrating cost-competitive cellulosic ethanol technology can be tracked. With an assumed feedstock cost for corn stover of $58.50/ton this target has historically been set at $1.41/gal ethanol for conversion costs only (exclusive of feedstock) and $2.15/gal total production cost (inclusive of feedstock) or minimum ethanol selling price (MESP). This year, fully integrated cellulosic ethanol production data generated by National Renewable Energy Laboratory (NREL) researchers in their Integrated Biorefinery Research Facility (IBRF) successfully demonstrated performance commensurate with both the FY 2012 SOT MESP target of $2.15/gal (2007$, $58.50/ton feedstock cost) and the conversion target of $1.41/gal through core research and process improvements in pretreatment, enzymatic hydrolysis, and fermentation.

  5. Development of efficient, integrated cellulosic biorefineries : LDRD final report.

    Energy Technology Data Exchange (ETDEWEB)

    Teh, Kwee-Yan; Hecht, Ethan S.; Shaddix, Christopher R.; Buffleben, George M.; Dibble, Dean C.; Lutz, Andrew E.

    2010-09-01

    Cellulosic ethanol, generated from lignocellulosic biomass sources such as grasses and trees, is a promising alternative to conventional starch- and sugar-based ethanol production in terms of potential production quantities, CO{sub 2} impact, and economic competitiveness. In addition, cellulosic ethanol can be generated (at least in principle) without competing with food production. However, approximately 1/3 of the lignocellulosic biomass material (including all of the lignin) cannot be converted to ethanol through biochemical means and must be extracted at some point in the biochemical process. In this project we gathered basic information on the prospects for utilizing this lignin residue material in thermochemical conversion processes to improve the overall energy efficiency or liquid fuel production capacity of cellulosic biorefineries. Two existing pretreatment approaches, soaking in aqueous ammonia (SAA) and the Arkenol (strong sulfuric acid) process, were implemented at Sandia and used to generated suitable quantities of residue material from corn stover and eucalyptus feedstocks for subsequent thermochemical research. A third, novel technique, using ionic liquids (IL) was investigated by Sandia researchers at the Joint Bioenergy Institute (JBEI), but was not successful in isolating sufficient lignin residue. Additional residue material for thermochemical research was supplied from the dilute-acid simultaneous saccharification/fermentation (SSF) pilot-scale process at the National Renewable Energy Laboratory (NREL). The high-temperature volatiles yields of the different residues were measured, as were the char combustion reactivities. The residue chars showed slightly lower reactivity than raw biomass char, except for the SSF residue, which had substantially lower reactivity. Exergy analysis was applied to the NREL standard process design model for thermochemical ethanol production and from a prototypical dedicated biochemical process, with process data

  6. North America markets for alcohol and alcohol-derived motor fuels and need for tax incentives

    International Nuclear Information System (INIS)

    Haigwood, B.

    1991-01-01

    The U.S. fuel alcohol and ether industry has grown from its infancy in 1979 to approximately 2.9 billion gallons of production capacity in 1991. With the emphasis on clean air, the uncertainties in the Middle East, and fluctuating oil prices, IRI believes the demand for alcohol-derived motor fuels is poised to begin a second phase of expansion. Historically, the two primary alcohol-derived motor fuels sold in the U.S. have been methyl tertiary butyl ether (MTBE) and ethanol. There is also a limited but growing use of methanol as 85% blendstock for gasoline. Since 1978, fuel ethanol has provided the U.S. petroleum industry with an additional source of supply, octane, and profit. Its price was based on the price of wholesale gasoline plus available federal and state tax incentives. These incentives allowed ethanol, with production costs of $1.00 to $1.25 per gallon, to compete with gasoline at prices of 40 to 65 per gallon. Without the federal and state tax incentives, it would not be economically feasible to sell or manufacture fuel ethanol. On the other hand, the largest consumption of methanol has been as a feedstock for the production of MTBE, the world's fastest growing chemical over the past seven years. MTBE prices are based on the cost of raising the octane level of gasoline, and this commodity does not receive subsidies. Beginning in 1992, IRI predicts the price relationship between ethanol, MTBE, and gasoline will change as U.S. refiners and marketers are required to include oxygenated fuels (alcohol-derived) in their gasoline. In total, over 60 billion gallons of gasoline will need to be reformulated by the year 2000. The increased demand for oxygen will result in a 2.5-billion gallon deficit of MTBE and 1.2-billion gallon deficit of ethanol by the year 2000. 2 tabs

  7. Lignocellulose pretreatment technologies affect the level of enzymatic cellulose oxidation by LPMO

    DEFF Research Database (Denmark)

    Rodríguez-Zúñiga, Ursula Fabiola; Cannella, David; de Campos Giordano, Roberto

    2015-01-01

    of the cellulose oxidizing enzyme lytic polysaccharide monooxygenase (LPMO). The highest activity of LPMO was observed for the hydrothermally pretreated biomasses, which also contained the highest level of lignin. All hydrolysis were done at high dry matter levels, using a commercial enzyme preparation containing......Sugarcane bagasse, corn stover, and wheat straw are among the most available resources for production of cellulosic ethanol. For these biomasses we study the influence of pre-treatment methods on the chemical composition, as well as on the subsequent reactions of enzymatic hydrolysis and oxidation...

  8. DEVELOPMENT OF MICROORGANISMS FOR CELLULOSE-BIOFUEL CONSOLIDATED BIOPROCESSINGS: METABOLIC ENGINEERS' TRICKS

    Directory of Open Access Journals (Sweden)

    Roberto Mazzoli

    2012-10-01

    By starting from the description of natural enzyme systems for plant biomass degradation and natural metabolic pathways for some of the most valuable product (i.e. butanol, ethanol, and hydrogen biosynthesis, this review describes state-of-the-art bottlenecks and solutions for the development of recombinant microbial strains for cellulosic biofuel CBP by metabolic engineering. Complexed cellulases (i.e. cellulosomes benefit from stronger proximity effects and show enhanced synergy on insoluble substrates (i.e. crystalline cellulose with respect to free enzymes. For this reason, special attention was held on strategies involving cellulosome/designer cellulosome-bearing recombinant microorganisms.

  9. Incentives and provider payment methods.

    Science.gov (United States)

    Barnum, H; Kutzin, J; Saxenian, H

    1995-01-01

    The mode of payment creates powerful incentives affecting provider behavior and the efficiency, equity and quality outcomes of health finance reforms. This article examines provider incentives as well as administrative costs, and institutional conditions for successful implementation associated with provider payment alternatives. The alternatives considered are budget reforms, capitation, fee-for-service, and case-based reimbursement. We conclude that competition, whether through a regulated private sector or within a public system, has the potential to improve the performance of any payment method. All methods generate both adverse and beneficial incentives. Systems with mixed forms of provider payment can provide tradeoffs to offset the disadvantages of individual modes. Low-income countries should avoid complex payment systems requiring higher levels of institutional development.

  10. 21 CFR 573.420 - Ethyl cellulose.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ethyl cellulose. 573.420 Section 573.420 Food and... Listing § 573.420 Ethyl cellulose. The food additive ethyl cellulose may be safely used in animal feed in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether containing...

  11. Evaluation of microcrystalline cellulose modifed from alpha ...

    African Journals Online (AJOL)

    Alpha cellulose was obtained from Costus afer and part of it was modified to microcrystalline cellulose (CAMCC). The physicochemical properties of the microcrystalline cellulose were determined and compared with those of commercial microcrystalline cellulose (Avicel 101). The swelling capacity, hydration capacity, loss ...

  12. 21 CFR 172.868 - Ethyl cellulose.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl cellulose. 172.868 Section 172.868 Food and... Multipurpose Additives § 172.868 Ethyl cellulose. The food additive ethyl cellulose may be safely used in food in accordance with the following prescribed conditions: (a) The food additive is a cellulose ether...

  13. Radiation degradation of cellulose

    International Nuclear Information System (INIS)

    Leonhardt, J.W.; Arnold, G.; Baer, M.; Gey, M.; Hubert, S.; Langguth, H.

    1984-01-01

    The application of straw and other cellulose polymers as feedstuff for ruminants is limited by its low digestibility. During recent decades it was attempted to increase the digestibility of straw by several chemical and physical methods. In this work some results of the degradation of gamma and electron treated wheat straw are reported. Complex methods of treatment (e.g. radiation influence and influence of lyes) are taken into consideration. In vitro-experiments with radiation treated straw show that the digestibility can be increased from 20% up to about 80%. A high pressure liquid chromatography method was used to analyze the hydrolysates. The contents of certain species of carbohydrates in the hydrolysates in dependence on the applied dose are given

  14. Preliminary studies on 1-vinyl-2-pyrrolidone grafting onto cellulose by pre-irradiation method

    Energy Technology Data Exchange (ETDEWEB)

    Severich, Patrick; Dutra, Rodrigo da Costa; Kodama, Yasko, E-mail: ykodama@ipen.br, E-mail: patrick.severich@ipen.br, E-mail: rodrigo.dutra@ipen.br [Instituto de Pesquisas Energética s e Nucleares (IPEN-CNEN/SP), São Paulo, SP (Brazil)

    2017-07-01

    Cellulose is considered a renewable biopolymer most abundant in nature. Better functional surfaces can be Obtained by modifying cellulose. On the other hand, poly vinyl pyrrolidone, PVP, is a synthetic nontoxic, water-soluble polymer frequently used in an extensive variety of applications including several pharmaceutical applications. Grafting 1-vinyl-2-pyrrolidone, NVP, onto polymeric cellulose can be obtained by ionizing radiation. Ionizing radiation grafting can be affected by several factors as environment, solvent, monomer concentration, temperature of graft reaction. Grafting by ionizing radiation can be performed by three methods, pre-irradiation, oxidation by peroxide and simultaneous irradiation. In this study, it was used pre-irradiation method of cellulose. Paper filter without ash, NVP without purification was used in this study. Paper samples were exposed to electron beam from Dynamitron Accelerator with radiation absorbed dose of 25 kGy. Influence of NVP concentration, temperature of reaction after irradiation on degree of grafting (DG) was studied. Also, cellulose radicals of grafted paper samples was studied by electron paramagnetic resonance using a Bruker X-band ESR at room temperature just after heating reaction. Small decrease of cellulose radicals was observed with increasing reaction temperature. It was observed DG small increase with increasing concentration of monomer in solution of water ethanol 50-50 v:v and rising temperature of reaction. Further tests using simultaneous method of grafting of NVP in cellulose paper, in water:ethanol 75:25 v:v solution, induced by gamma irradiation were performed. It was observed homopolymerization forming PVP with increasing monomer concentration. (author)

  15. Preliminary studies on 1-vinyl-2-pyrrolidone grafting onto cellulose by pre-irradiation method

    International Nuclear Information System (INIS)

    Severich, Patrick; Dutra, Rodrigo da Costa; Kodama, Yasko

    2017-01-01

    Cellulose is considered a renewable biopolymer most abundant in nature. Better functional surfaces can be Obtained by modifying cellulose. On the other hand, poly vinyl pyrrolidone, PVP, is a synthetic nontoxic, water-soluble polymer frequently used in an extensive variety of applications including several pharmaceutical applications. Grafting 1-vinyl-2-pyrrolidone, NVP, onto polymeric cellulose can be obtained by ionizing radiation. Ionizing radiation grafting can be affected by several factors as environment, solvent, monomer concentration, temperature of graft reaction. Grafting by ionizing radiation can be performed by three methods, pre-irradiation, oxidation by peroxide and simultaneous irradiation. In this study, it was used pre-irradiation method of cellulose. Paper filter without ash, NVP without purification was used in this study. Paper samples were exposed to electron beam from Dynamitron Accelerator with radiation absorbed dose of 25 kGy. Influence of NVP concentration, temperature of reaction after irradiation on degree of grafting (DG) was studied. Also, cellulose radicals of grafted paper samples was studied by electron paramagnetic resonance using a Bruker X-band ESR at room temperature just after heating reaction. Small decrease of cellulose radicals was observed with increasing reaction temperature. It was observed DG small increase with increasing concentration of monomer in solution of water ethanol 50-50 v:v and rising temperature of reaction. Further tests using simultaneous method of grafting of NVP in cellulose paper, in water:ethanol 75:25 v:v solution, induced by gamma irradiation were performed. It was observed homopolymerization forming PVP with increasing monomer concentration. (author)

  16. Surface Photochemistry: Benzophenone as a Probe for the Study of Modified Cellulose Fibres

    Directory of Open Access Journals (Sweden)

    L. F. Vieira Ferreira

    2007-01-01

    Full Text Available This work reports the use of benzophenone, a very well characterized probe, to study new hosts (i.e., modified celluloses grafted with alkyl chains bearing 12 carbon atoms by surface esterification. Laser-induced room temperature luminescence of air-equilibrated or argon-purged solid powdered samples of benzophenone adsorbed onto the two modified celluloses, which will be named C12-1500 and C12-1700, revealed the existence of a vibrationally structured phosphorescence emission of benzophenone in the case where ethanol was used for sample preparation, while a nonstructured emission of benzophenone exists when water was used instead of ethanol. The decay times of the benzophenone emission vary greatly with the solvent used for sample preparation and do not change with the alkylation degree in the range of 1500–1700 micromoles of alkyl chains per gram of cellulose. When water was used as a solvent for sample preparation, the shortest lifetime for the benzophenone emission was observed; this result is similar to the case of benzophenone adsorbed onto the “normal” microcrystalline cellulose surface, with this latter case previously reported by Vieira Ferreira et al. in 1995. This is due to the more efficient hydrogen abstraction reaction from the glycoside rings of cellulose when compared with hydrogen abstraction from the alkyl chains of the modified celluloses. Triplet-triplet transient absorption of benzophenone was obtained in both cases and is the predominant absorption immediately after laser pulse, while benzophenone ketyl radical formation occurs in a microsecond time scale both for normal and modified celluloses.

  17. Use of ethanol in public urban transport: BEST (BioEthanol for Sustainable Transport) Project; Uso de etanol no transporte publico urbano: projeto BEST (Bio Ethanol para o Transporte Sustentavel)

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Jose Roberto; Apolinario, Sandra; Pecora, Vanessa [Universidade de Sao Paulo (CENBIO/USP), SP (Brazil). Inst. de Eletrotecnica e Energia. Centro Nacional de Referencia em Biomassa; Velazquez, Silvia [Universidade Presbiteriana Mackenzie, Sao Paulo, SP (Brazil)

    2008-07-01

    This paper present the BEST project - Bio Ethanol for Sustainable Transport, that aims to promote the ethanol usage, replacing diesel, in the urban public transport in Brazil and worldwide. Apart from Sao Paulo, leading city in the Americas, another eight cities located in Europe and Asia takes part in the project. One of the Brazilian project's goals is to evaluate ethanol usage as diesel fuel replacement in public transport buses by comparatively following the operational output of the experimental fleet, taking as reference an equivalent diesel bus. The utilized test vehicles will be evaluated and monitored to demonstrate ethanol energetic efficiency and, after the results the BEST project and the European Union will set a blue print for public policies to incentive ethanol usage in the urban public transport. The results will allow identifying technical and economical barriers that will eventually overlap the viability process of this technology in the Brazilian public transport. (author)

  18. Use of ethanol in public urban transport: BEST (BioEthanol for Sustainable Transport) Project; Uso de etanol no transporte publico urbano: projeto BEST (Bio Ethanol para o Transporte Sustentavel)

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Jose Roberto; Apolinario, Sandra; Pecora, Vanessa [Universidade de Sao Paulo (CENBIO/USP), SP (Brazil). Inst. de Eletrotecnica e Energia. Centro Nacional de Referencia em Biomassa; Velazquez, Silvia [Universidade Presbiteriana Mackenzie, Sao Paulo, SP (Brazil)

    2008-07-01

    This paper present the BEST project - Bio Ethanol for Sustainable Transport, that aims to promote the ethanol usage, replacing diesel, in the urban public transport in Brazil and worldwide. Apart from Sao Paulo, leading city in the Americas, another eight cities located in Europe and Asia takes part in the project. One of the Brazilian project's goals is to evaluate ethanol usage as diesel fuel replacement in public transport buses by comparatively following the operational output of the experimental fleet, taking as reference an equivalent diesel bus. The utilized test vehicles will be evaluated and monitored to demonstrate ethanol energetic efficiency and, after the results the BEST project and the European Union will set a blue print for public policies to incentive ethanol usage in the urban public transport. The results will allow identifying technical and economical barriers that will eventually overlap the viability process of this technology in the Brazilian public transport. (author)

  19. Acetone-based cellulose solvent.

    Science.gov (United States)

    Kostag, Marc; Liebert, Tim; Heinze, Thomas

    2014-08-01

    Acetone containing tetraalkylammonium chloride is found to be an efficient solvent for cellulose. The addition of an amount of 10 mol% (based on acetone) of well-soluble salt triethyloctylammonium chloride (Et3 OctN Cl) adjusts the solvent's properties (increases the polarity) to promote cellulose dissolution. Cellulose solutions in acetone/Et3 OctN Cl have the lowest viscosity reported for comparable aprotic solutions making it a promising system for shaping processes and homogeneous chemical modification of the biopolymer. Recovery of the polymer and recycling of the solvent components can be easily achieved. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Forage Quality and Composition Measurements as Predictors of Ethanol Yield from Maize (Zea mays L.) Stover

    Science.gov (United States)

    Improvement of biofeedstock quality for cellulosic ethanol production will be facilitated by inexpensive and rapid methods of evaluation, such as those already employed in the field of ruminant nutrition. Our objective was to evaluate whether forage quality and compositional measurements could be u...

  1. Forage crops as substrate for animal feed and ethanol production in ...

    African Journals Online (AJOL)

    The results indicate the effect of harvesting time on their composition, including the contents of cellulose, lignin, and crude protein, thus affecting the ethanol yield and quality of animal feed. Ruzi grass, harvested 45 days after being planted, was shown to be the most suitable substrate for animal feed due to its highest crude ...

  2. Upper Midwestern U.S. consumers and ethanol: Knowledge, beliefs and consumption

    International Nuclear Information System (INIS)

    Johnson, Dana M.; Halvorsen, Kathleen E.; Solomen, Barry D.

    2011-01-01

    This study uses multivariate statistical methods to explore the beliefs of upper Midwestern U.S. residents about global climate change, and possible consumer responses to determine their willingness to pay more for cellulosic ethanol from multiple feedstocks. A mail survey was sent to residents of Michigan, Minnesota, and Wisconsin to determine baseline knowledge, attitudes and beliefs on several aspects of these issues, with a focus on the emerging market for cellulosic ethanol. First, survey responses were compiled and principal components analysis was used to reduce the dimensionality of the data. This resulted in seven factors and a theoretical framework to help understand consumers' beliefs about climate change and possible energy policy responses. Second, these results were combined with insights from previous studies that were used as input for further research hypotheses and multivariate analyses. The factor scores from principal components analysis along with the some of the key control variables (i.e., gender, income, and rural/urban) served as independent variables in three revised multiple regression models of consumer's willingness to pay (WTP) their fair share of any additional cost of cellulosic ethanol, as reported in an earlier study. Four explanatory variables were found to be significant determinants of WTP in every model: environment, energy consumption, and climate change; concerns about climate change impacts; inability to stop climate change; and gasoline prices and consumption. These results suggest strong public support and consumer WTP for cellulosic ethanol production in the region.

  3. Cellulose microfibril structure: inspirations from plant diversity

    Science.gov (United States)

    Roberts, A. W.

    2018-03-01

    Cellulose microfibrils are synthesized at the plasma membrane by cellulose synthase catalytic subunits that associate to form cellulose synthesis complexes. Variation in the organization of these complexes underlies the variation in cellulose microfibril structure among diverse organisms. However, little is known about how the catalytic subunits interact to form complexes with different morphologies. We are using an evolutionary approach to investigate the roles of different catalytic subunit isoforms in organisms that have rosette-type cellulose synthesis complexes.

  4. Lifecycle optimized ethanol-gasoline blends for turbocharged engines

    KAUST Repository

    Zhang, Bo

    2016-08-16

    This study presents a lifecycle (well-to-wheel) analysis to determine the CO2 emissions associated with ethanol blended gasoline in optimized turbocharged engines. This study provides a more accurate assessment on the best-achievable CO2 emission of ethanol blended gasoline mixtures in future engines. The optimal fuel blend (lowest CO2 emitting fuel) is identified. A range of gasoline fuels is studied, containing different ethanol volume percentages (E0–E40), research octane numbers (RON, 92–105), and octane sensitivities (8.5–15.5). Sugarcane-based and cellulosic ethanol-blended gasolines are shown to be effective in reducing lifecycle CO2 emission, while corn-based ethanol is not as effective. A refinery simulation of production emission was utilized, and combined with vehicle fuel consumption modeling to determine the lifecycle CO2 emissions associated with ethanol-blended gasoline in turbocharged engines. The critical parameters studied, and related to blended fuel lifecycle CO2 emissions, are ethanol content, research octane number, and octane sensitivity. The lowest-emitting blended fuel had an ethanol content of 32 vol%, RON of 105, and octane sensitivity of 15.5; resulting in a CO2 reduction of 7.1%, compared to the reference gasoline fuel and engine technology. The advantage of ethanol addition is greatest on a per unit basis at low concentrations. Finally, this study shows that engine-downsizing technology can yield an additional CO2 reduction of up to 25.5% in a two-stage downsized turbocharged engine burning the optimum sugarcane-based fuel blend. The social cost savings in the USA, from the CO2 reduction, is estimated to be as much as $187 billion/year. © 2016 Elsevier Ltd

  5. Optimization of microwave pretreatment on wheat straw for ethanol production

    DEFF Research Database (Denmark)

    Xu, Jian; Chen, Hongzhang; Kádár, Zsófia

    2011-01-01

    An orthogonal design (L9(34)) was used to optimize the microwave pretreatment on wheat straw for ethanol production. The orthogonal analysis was done based on the results obtained from the nine pretreatments. The effect of four factors including the ratio of biomass to NaOH solution, pretreatment...... time, microwave power, and the concentration of NaOH solution with three different levels on the chemical composition, cellulose/hemicellulose recoveries and ethanol concentration was investigated. According to the orthogonal analysis, pretreatment with the ratio of biomass to liquid at 80 g kg−1......, the NaOH concentration of 10 kg m−3, the microwave power of 1000 W for 15 min was confirmed to be the optimal condition. The ethanol yield was 148.93 g kg−1 wheat straw at this condition, much higher than that from the untreated material which was only 26.78 g kg−1....

  6. Ethanol Transportation Backgrounder

    OpenAIRE

    Denicoff, Marina R.

    2007-01-01

    For the first 6 months of 2007, U.S. ethanol production totaled nearly 3 billion gallons—32 percent higher than the same period last year. As of August 29, there were 128 ethanol plants with annual production capacity totaling 6.78 billion gallons, and an additional 85 plants were under construction. U.S. ethanol production capacity is expanding rapidly and is currently expected to exceed 13 billion gallons per year by early 2009, if not sooner. Ethanol demand has increased corn prices and le...

  7. Recent Strategies in Preparation of Cellulose Nanocrystals and Cellulose Nanofibrils Derived from Raw Cellulose Materials

    Directory of Open Access Journals (Sweden)

    Hongxiang Xie

    2018-01-01

    Full Text Available The recent strategies in preparation of cellulose nanocrystals (CNCs and cellulose nanofibrils (CNFs were described. CNCs and CNFs are two types of nanocelluloses (NCs, and they possess various superior properties, such as large specific surface area, high tensile strength and stiffness, low density, and low thermal expansion coefficient. Due to various applications in biomedical engineering, food, sensor, packaging, and so on, there are many studies conducted on CNCs and CNFs. In this review, various methods of preparation of CNCs and CNFs are summarized, including mechanical, chemical, and biological methods. The methods of pretreatment of cellulose are described in view of the benefits to fibrillation.

  8. WOOD CELLULOSE ACETATE MEMBRANE 179

    African Journals Online (AJOL)

    DR. AMINU

    2013-06-01

    Jun 1, 2013 ... 1988), cosmetics and food additives or pharmaceutical applications (Wellisch .... displaced by sample. Determination of percent α-, β- and γ–cellulose ..... addition, the smaller pore diameter would lead to a greater exclusion of ...

  9. Versatile High-Performance Regenerated Cellulose Membranes Prepared using Trimethylsilyl Cellulose as a Precursor

    KAUST Repository

    Puspasari, Tiara

    2018-01-01

    (TMSC), a highly soluble cellulose derivative, as a precursor for the fabrication of cellulose thin film composite membranes. TMSC is an attractive precursor to assemble thin cellulose films with good deposition behavior and film morphology; cumbersome

  10. Legal incentives for minimizing waste

    International Nuclear Information System (INIS)

    Clearwater, S.W.; Scanlon, J.M.

    1991-01-01

    Waste minimization, or pollution prevention, has become an integral component of federal and state environmental regulation. Minimizing waste offers many economic and public relations benefits. In addition, waste minimization efforts can also dramatically reduce potential criminal requirements. This paper addresses the legal incentives for minimizing waste under current and proposed environmental laws and regulations

  11. Incentives in Supply Function Equilibrium

    DEFF Research Database (Denmark)

    Vetter, Henrik

    2015-01-01

    The author analyses delegation in homogenous duopoly under the assumption that firm-managers compete in supply functions. He reverses earlier findings in that owners give managers incentives to act in an accommodating way. That is, optimal delegation reduces per-firm output and increases profits ...

  12. Incentives and regulation in banking

    NARCIS (Netherlands)

    Martynova, N.

    2015-01-01

    The financial crisis of 2007-2008 has unveiled the hidden flaws in the regulatory framework of the financial sector. The rules of the game established by regulators were not stringent enough and provided bankers with wrong incentives to gamble with depositors’ money. There are two major challenges

  13. Offering Incentives from the Outside

    DEFF Research Database (Denmark)

    Emmanuel, Nikolas G.

    2017-01-01

    Incentives offer a good deal of underexplored opportunities to help manage conflict by encouraging political bargaining. This study has two primary objectives. First, it furthers the discussion of how external third parties can help manage conflicts. Second, it offers a typology of the available ...

  14. Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, December 1, 1978-February 28, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Wang, D.I.C.; Cooney, C.L.; Demain, A.L.; Gomez, R.F.; Sinskey, A.J.

    1979-02-01

    The ongoing progress of a coordinated research program aimed at optimizing the biodegradation of cellulosic biomass to ethanol and chemical feedstocks is summarized. Growth requirements and genetic manipulations of clostridium thermocellum for selection of high cellulose producers are reported. The enzymatic activity of the cellulase produced by these organisms was studied. The soluble sugars produced from hydrolysis were analyzed. Increasing the tolerance of C. thermocellum to ethanol during liquid fuel production, increasing the rate of product formation, and directing the catabolism to selectively achieve high ethanol concentrations with respect to other products were studied. Alternative substrates for C. thermocellum were evaluated. Studies on the utilization of xylose were performed. Single stage fermentation of cellulose using mixed cultures of C. thermocellum and C. thermosaccharolyticum were studied. The study of the production of chemical feedstocks focused on acrylic acid, acetone/butanol, acetic acid, and lactic acid.

  15. Ionizing Radiation Conversion of Lignocellulosic Biomass from Sugarcane Bagasse to Production Ethanol Biofuel

    International Nuclear Information System (INIS)

    Duarte, C.L.; Mori, M.N.; Oikawa, H.; Finguerut, J.; Galvão, A.; Nagatomi, H.R.; Célia, M.

    2010-01-01

    Sugarcane bagasse has been considered as a substrate for single cell protein, animal feed, and renewable energy production. Sugarcane bagasse generally contain up to 45% glucose polymer cellulose, 40% hemicelluloses, and 20% lignin. Pure cellulose is readily depolymerised by radiation, but in biomass, the cellulose is intimately bonded with lignin, that protect it from radiation effects. The objective of this study is the evaluation of the electron beam irradiation as a pre-treatment to enzymatic hydrolysis of cellulose in order to facilitate its fermentation and improves the production of ethanol biofuel. Samples of sugarcane bagasse were obtained in sugar/ethanol Iracema Mill sited in Piracicaba, Brazil, and were irradiated using Radiation Dynamics Electron Beam Accelerator with 1.5 MeV energy and 37kW, in batch systems. The applied absorbed doses of the fist sampling, Bagasse A, were 20 kGy, 50 kGy, 100 kGy and 200 kGy. After the evaluation the preliminary obtained results, it was applied lower absorbed doses in the second assay: 5 kGy, 10 kGy, 20 kGy, 30 kGy, 50 kGy, 70 kGy, 100 kGy and 150 kGy. The electron beam processing took to changes in the sugarcane bagasse structure and composition, lignin and cellulose cleavage. The yield of enzymatic hydrolyzes of cellulose increase about 75 % with 30 kGy of absorbed dose. (author)

  16. Bacterial cellulose/boehmite composites

    International Nuclear Information System (INIS)

    Salvi, Denise T.B. de; Barud, Hernane S.; Messaddeq, Younes; Ribeiro, Sidney J.L.; Caiut, Jose Mauricio A.

    2011-01-01

    Composites based on bacterial cellulose membranes and boehmite were obtained. SEM results indicate that the bacterial cellulose (BC) membranes are totally covered by boehmite and obtained XRD patterns suggest structural changes due to this boehmite addition. Thermal stability is accessed through TG curves and is dependent on boehmite content. Transparency is high comparing to pure BC as can be seen through UV-vis absorption spectroscopy. (author)

  17. Calcium carbonate growth in the presence of water soluble cellulose ethers

    International Nuclear Information System (INIS)

    Zhang Fengju; Yang Xinguo; Tian Fei

    2009-01-01

    Calcium carbonate precipitation was performed in the presence of methyl cellulose (MC) and two kinds of hydroxyethyl cellulose (HEC FD-10000, HEC FD-30000). The results demonstrated that the final product morphology and structure of CaCO 3 crystals are highly sensitive to the concentration of the cellulose ethers aqueous solution. By precisely controlling their concentrations, all these three cellulose ethers solutions have the ability of protecting metastable vaterite from thermodynamically transforming into stable calcite. The intermediate products investigation showed to some extent the phase transformation of calcium carbonate in its growing process from metastable vaterite to calcite and indicated that the calcium carbonate crystal growth in HEC solutions occurs through dissolution and reprecipitation process. Calcium carbonate growth in both presence of HEC and ethanol or Mg 2+ was also examined. This work demonstrates the potential of water soluble cellulose ethers in controlling biominerals crystallization and growth. The results are revelatory for biomineralization and fabricating new organic-inorganic hybrids based on cellulose derivatives.

  18. Biotechnological production of ethanol from renewable resources by Neurospora crassa: an alternative to conventional yeast fermentations?

    Science.gov (United States)

    Dogaris, Ioannis; Mamma, Diomi; Kekos, Dimitris

    2013-02-01

    Microbial production of ethanol might be a potential route to replace oil and chemical feedstocks. Bioethanol is by far the most common biofuel in use worldwide. Lignocellulosic biomass is the most promising renewable resource for fuel bioethanol production. Bioconversion of lignocellulosics to ethanol consists of four major unit operations: pretreatment, hydrolysis, fermentation, and product separation/distillation. Conventional bioethanol processes for lignocellulosics apply commercial fungal cellulase enzymes for biomass hydrolysis, followed by yeast fermentation of resulting glucose to ethanol. The fungus Neurospora crassa has been used extensively for genetic, biochemical, and molecular studies as a model organism. However, the strain's potential in biotechnological applications has not been widely investigated and discussed. The fungus N. crassa has the ability to synthesize and secrete all three enzyme types involved in cellulose hydrolysis as well as various enzymes for hemicellulose degradation. In addition, N. crassa has been reported to convert to ethanol hexose and pentose sugars, cellulose polymers, and agro-industrial residues. The combination of these characteristics makes N. crassa a promising alternative candidate for biotechnological production of ethanol from renewable resources. This review consists of an overview of the ethanol process from lignocellulosic biomass, followed by cellulases and hemicellulases production, ethanol fermentations of sugars and lignocellulosics, and industrial application potential of N. crassa.

  19. Ethanol production from banana peels using statistically optimized simultaneous saccharification and fermentation process.

    Science.gov (United States)

    Oberoi, Harinder Singh; Vadlani, Praveen V; Saida, Lavudi; Bansal, Sunil; Hughes, Joshua D

    2011-07-01

    Dried and ground banana peel biomass (BP) after hydrothermal sterilization pretreatment was used for ethanol production using simultaneous saccharification and fermentation (SSF). Central composite design (CCD) was used to optimize concentrations of cellulase and pectinase, temperature and time for ethanol production from BP using SSF. Analysis of variance showed a high coefficient of determination (R(2)) value of 0.92 for ethanol production. On the basis of model graphs and numerical optimization, the validation was done in a laboratory batch fermenter with cellulase, pectinase, temperature and time of nine cellulase filter paper unit/gram cellulose (FPU/g-cellulose), 72 international units/gram pectin (IU/g-pectin), 37 °C and 15 h, respectively. The experiment using optimized parameters in batch fermenter not only resulted in higher ethanol concentration than the one predicted by the model equation, but also saved fermentation time. This study demonstrated that both hydrothermal pretreatment and SSF could be successfully carried out in a single vessel, and use of optimized process parameters helped achieve significant ethanol productivity, indicating commercial potential for the process. To the best of our knowledge, ethanol concentration and ethanol productivity of 28.2 g/l and 2.3 g/l/h, respectively from banana peels have not been reported to date. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Variation in Incentive Effects across Neighbourhoods

    Directory of Open Access Journals (Sweden)

    Mark J Hanly

    2014-03-01

    Full Text Available Small monetary incentives increase survey cooperation rates, however evidence suggests that the appeal of incentives may vary across sample subgroups. Fieldwork budgets can be most effectively distributed by targeting those subgroups where incentives will have the strongest appeal. We examine data from a randomised experiment implemented in the pilot phase of the Irish Longitudinal Study of Ageing, which randomly assigned households to receive a higher (€25 or lower (€10 incentive amount. Using a random effects logistic regression model, we observe a variable effect of the higher incentive across geographic neighbourhoods. The higher incentive has the largest impact in neighbourhoods where baseline cooperation is low, as predicted by Leverage-Saliency theory. Auxiliary neighbourhood-level variables are linked to the sample frame to explore this variation further, however none of these moderate the incentive effect, suggesting that richer information is needed to identify sample subgroups where incentive budgets should be directed.

  1. INFLUENCE OF CELLULOSE POLYMERIZATION DEGREE AND CRYSTALLINITY ON KINETICS OF CELLULOSE DEGRADATION

    OpenAIRE

    Edita Jasiukaitytė-Grojzdek,; Matjaž Kunaver,; Ida Poljanšek

    2012-01-01

    Cellulose was treated in ethylene glycol with p-toluene sulfonic acid monohydrate as a catalyst at different temperatures. At the highest treatment temperature (150 °C) liquefaction of wood pulp cellulose was achieved and was dependant on cellulose polymerization degree (DP). Furthermore, the rate of amorphous cellulose weight loss was found to increase with cellulose degree of polymerization, while the rate of crystalline cellulose weight loss was reciprocal to the size of the crystallites. ...

  2. Cellulose biosynthesis in higher plants

    Directory of Open Access Journals (Sweden)

    Krystyna Kudlicka

    2014-01-01

    Full Text Available Knowledge of the control and regulation of cellulose synthesis is fundamental to an understanding of plant development since cellulose is the primary structural component of plant cell walls. In vivo, the polymerization step requires a coordinated transport of substrates across membranes and relies on delicate orientations of the membrane-associated synthase complexes. Little is known about the properties of the enzyme complexes, and many questions about the biosynthesis of cell wall components at the cell surface still remain unanswered. Attempts to purify cellulose synthase from higher plants have not been successful because of the liability of enzymes upon isolation and lack of reliable in vitro assays. Membrane preparations from higher plant cells incorporate UDP-glucose into a glucan polymer, but this invariably turns out to be predominantly β -1,3-linked rather than β -1,4-linked glucans. Various hypotheses have been advanced to explain this phenomenon. One idea is that callose and cellulose-synthase systems are the same, but cell disruption activates callose synthesis preferentially. A second concept suggests that a regulatory protein as a part of the cellulose-synthase complex is rapidly degraded upon cell disruption. With new methods of enzyme isolation and analysis of the in vitro product, recent advances have been made in the isolation of an active synthase from the plasma membrane whereby cellulose synthase was separated from callose synthase.

  3. Market penetration of ethanol

    International Nuclear Information System (INIS)

    Szulczyk, Kenneth R.; McCarl, Bruce A.; Cornforth, Gerald

    2010-01-01

    This research examines in detail the technology and economics of substituting ethanol for gasoline. This endeavor examines three issues. First, the benefits of ethanol/gasoline blends are examined, and then the technical problems of large-scale implementation of ethanol. Second, ethanol production possibilities are examined in detail from a variety of feedstocks and technologies. The feedstocks are the starch/sugar crops and crop residues, while the technologies are corn wet mill, dry grind, and lignocellulosic fermentation. Examining in detail the production possibilities allows the researchers to identity the extent of technological change, production costs, byproducts, and GHG emissions. Finally, a U.S. agricultural model, FASOMGHG, is updated which predicts the market penetration of ethanol given technological progress, variety of technologies and feedstocks, market interactions, energy prices, and GHG prices. FASOMGHG has several interesting results. First, gasoline prices have a small expansionary impact on the U.S. ethanol industry. Both agricultural producers' income and cost both increase with higher energy prices. If wholesale gasoline is $4 per gallon, the predicted ethanol market penetration attains 53% of U.S. gasoline consumption in 2030. Second, the corn wet mill remains an important industry for ethanol production, because this industry also produces corn oil, which could be converted to biodiesel. Third, GHG prices expand the ethanol industry. However, the GHG price expands the corn wet mill, but has an ambiguous impact on lignocellulosic ethanol. Feedstocks for lignocellulosic fermentation can also be burned with coal to generate electricity. Both industries are quite GHG efficient. Finally, U.S. government subsidies on biofuels have an expansionary impact on ethanol production, but may only increase market penetration by an additional 1% in 2030, which is approximately 6 billion gallons. (author)

  4. Determining the potential of inedible weed biomass for bio-energy and ethanol production

    Directory of Open Access Journals (Sweden)

    Siripong Premjet

    2013-02-01

    Full Text Available Surveys of indigenous weeds in six provinces located in the low northern part of Thailand were undertaken to determine the potential of weed biomass for bio-energy and bio-ethanol. The results reveal that most of the weed samples had low moisture contents and high lower heating values (LHVs. The LHVs at the highest level, ranging from 17.7 to 18.9 Mg/kg, and at the second highest level, ranging from 16.4 to 17.6 Mg/kg, were obtained from 11 and 31 weed species, respectively. It was found that most of the collected weed samples contained high cellulose and low lignin contents. Additionally, an estimate of the theoretical ethanol yields based on the amount of cellulose and hemicellulose in each weed species indicated that a high ethanol yield resulted from weed biomasses with high cellulose and hemicellulose contents. Among the collected weed species, the highest level of ethanol yield, ranging from 478.9 to 548.5 L/ton (substrate, was achieved from 11 weed species. It was demonstrated that most of the collected weed species tested have the potential for thermal conversion and can be used as substrates for ethanol production.

  5. Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1-August 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Wang, D. I.C.

    1980-09-01

    Progress is reported in this coordinated research program to effect the microbiological degradation of cellulosic biomass by anaerobic microorganisms possessing cellulolytic enzymes. Three main areas of research are discussed: increasing enzyme levels through genetics, mutations, and genetic manipulation; the direct conversion of cellulosic biomass to liquid fuel (ethanol); and the production of chemical feedstocks from biomass (acrylic acid, acetone/butanol, and acetic acid). (DMC)

  6. The Effect of Incentives and Meta-incentives on the Evolution of Cooperation.

    Directory of Open Access Journals (Sweden)

    Isamu Okada

    2015-05-01

    Full Text Available Although positive incentives for cooperators and/or negative incentives for free-riders in social dilemmas play an important role in maintaining cooperation, there is still the outstanding issue of who should pay the cost of incentives. The second-order free-rider problem, in which players who do not provide the incentives dominate in a game, is a well-known academic challenge. In order to meet this challenge, we devise and analyze a meta-incentive game that integrates positive incentives (rewards and negative incentives (punishments with second-order incentives, which are incentives for other players' incentives. The critical assumption of our model is that players who tend to provide incentives to other players for their cooperative or non-cooperative behavior also tend to provide incentives to their incentive behaviors. In this paper, we solve the replicator dynamics for a simple version of the game and analytically categorize the game types into four groups. We find that the second-order free-rider problem is completely resolved without any third-order or higher (meta incentive under the assumption. To do so, a second-order costly incentive, which is given individually (peer-to-peer after playing donation games, is needed. The paper concludes that (1 second-order incentives for first-order reward are necessary for cooperative regimes, (2 a system without first-order rewards cannot maintain a cooperative regime, (3 a system with first-order rewards and no incentives for rewards is the worst because it never reaches cooperation, and (4 a system with rewards for incentives is more likely to be a cooperative regime than a system with punishments for incentives when the cost-effect ratio of incentives is sufficiently large. This solution is general and strong in the sense that the game does not need any centralized institution or proactive system for incentives.

  7. The Effect of Incentives and Meta-incentives on the Evolution of Cooperation.

    Science.gov (United States)

    Okada, Isamu; Yamamoto, Hitoshi; Toriumi, Fujio; Sasaki, Tatsuya

    2015-05-01

    Although positive incentives for cooperators and/or negative incentives for free-riders in social dilemmas play an important role in maintaining cooperation, there is still the outstanding issue of who should pay the cost of incentives. The second-order free-rider problem, in which players who do not provide the incentives dominate in a game, is a well-known academic challenge. In order to meet this challenge, we devise and analyze a meta-incentive game that integrates positive incentives (rewards) and negative incentives (punishments) with second-order incentives, which are incentives for other players' incentives. The critical assumption of our model is that players who tend to provide incentives to other players for their cooperative or non-cooperative behavior also tend to provide incentives to their incentive behaviors. In this paper, we solve the replicator dynamics for a simple version of the game and analytically categorize the game types into four groups. We find that the second-order free-rider problem is completely resolved without any third-order or higher (meta) incentive under the assumption. To do so, a second-order costly incentive, which is given individually (peer-to-peer) after playing donation games, is needed. The paper concludes that (1) second-order incentives for first-order reward are necessary for cooperative regimes, (2) a system without first-order rewards cannot maintain a cooperative regime, (3) a system with first-order rewards and no incentives for rewards is the worst because it never reaches cooperation, and (4) a system with rewards for incentives is more likely to be a cooperative regime than a system with punishments for incentives when the cost-effect ratio of incentives is sufficiently large. This solution is general and strong in the sense that the game does not need any centralized institution or proactive system for incentives.

  8. Merger incentives and the failing firm defense

    NARCIS (Netherlands)

    Bouckaert, J.M.C.; Kort, P.M.

    2014-01-01

    The merger incentives between profitable firms differ fundamentally from the incentives of a profitable firm to merge with a failing firm. We investigate these incentives under different modes of price competition and Cournot behavior. Our main finding is that firms strictly prefer exit of the

  9. Effort and Selection Effects of Incentive Contracts

    NARCIS (Netherlands)

    Bouwens, J.F.M.G.; van Lent, L.A.G.M.

    2003-01-01

    We show that the improved effort of employees associated with incentive contracts depends on the properties of the performance measures used in the contract.We also find that the power of incentives in the contract is only indirectly related to any improved employee effort.High powered incentive

  10. Earnings progression, human capital and incentives

    DEFF Research Database (Denmark)

    Frederiksen, Anders

    progression by investigating the effects of on-the-job human capital acquisition, explicit short-run incentives and career concern incentives on earnings progression. The model leads to predictions about the incentive structure and the progression in both cross-sectional and individual earnings which...

  11. Development of Biocomposites with Antioxidant Activity Based on Red Onion Extract and Acetate Cellulose

    Directory of Open Access Journals (Sweden)

    Carol López de Dicastillo

    2015-08-01

    Full Text Available Antioxidant biocomposites have been successfully developed from cellulose acetate, eco-friendly triethyl citrate plasticizer and onion extract as a source of natural antioxidants. First, an onion extraction process was optimized to obtain the extract with highest antioxidant power. Extracts under absolute ethanol and ethanol 85% were the extracts with the highest antioxidant activity, which were the characterized through different methods, DPPH (2,2-diphenyl-1-picrylhydrazyl and ABTS (2,2ʹ-azinobis(3-ethylbenzothiazoline-6-sulphonate, that measure radical scavenger activity, and polyphenolic and flavonoid content. Afterwards, the extract was incorporated in cellulose acetate as polymer matrix owing to develop an active material intended to oxidative sensitive food products packaging. Different concentrations of onion extract and plasticizer were statistically studied by using response surface methodology in order to analyze the influence of both factors on the release of active compounds and therefore the antioxidant activity of these materials.

  12. Bioconversion of plant biomass to ethanol. Annual report and revised research plan, January 1977--January 1978

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, R.E.; Bellamy, W.D.; Su, T.M.

    1978-03-23

    The objective of this research is to demonstrate on a laboratory scale the technical feasibility of the direct microbial conversion of pretreated wood to ethanol. During the first year of this contract, we investigated the feasibility of biologically delignifying wood with C. pruinosum and directly fermenting the pretreated wood to ethanol with a mixed culture. Bench-top fermentations of a thermophilic bacillus growing on glucose and of a mixed culture of thermophilic sporocytophaga (US) and a thermophilic bacillus growing on microcrystalline and amorphous cellulose were evaluated for growth and ethanol production. In the mixed culture fermentation of amorphous and microcrystalline cellulose, the specific rate of substrate depletion was calculated to be 0.087 hr/sup -1/ and 0.0346 hr/sup -1/, respectively. However, defining the growth requirements of C. pruinosum and sporocytophaga (US) proved more difficult than originally anticipated. In order to achieve the program objectives within the contract period, a revised research plan was developed based upon chemical pretreatment and the direct fermentation of pretreated hardwood to ethanol. In place of the biological delignification pretreatment step, we have substituted a chemically supplemented steam pretreatment step to partially delignify wood and to enhance its accessibility to microbial utilization. Clostridium thermocellum, which ferments cellulose directly to ethanol and acetic acid, has replaced the mixed culture fermentation stage for ethanol production. Research on the production of ethanol from xylose by the thermophilic bacillus ZB-B2 is retained as one means of utilizing the hemicellulose fraction of hardwood. Work on the genetic improvement of the ethanol yields of both cultures by suppressing acetic acid production is also retained. The rationale, experimental approach, and economic considerations of this revised research plan are also presented.

  13. Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification

    Science.gov (United States)

    Liu, Xiumei; Xu, Wenjuan; Mao, Liaoyuan; Zhang, Chao; Yan, Peifang; Xu, Zhanwei; Zhang, Z. Conrad

    2016-02-01

    Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simple biomass pretreatment. Here we report an in-situ detoxification strategy by PEG exo-protection of an industrial dry yeast (starch-base). The exo-protected yeast cells displayed remarkably boosted vitality with high tolerance to toxic inhibitory compounds, and with largely improved ethanol productivity from crude hydrolysate derived from a pretreated lignocellulose. The PEG chemical exo-protection makes the industrial S. cerevisiae yeast directly applicable for the production of cellulosic ethanol with substantially improved productivity and yield, without of the need to use genetically modified microorganisms.

  14. The effective use of property tax incentives for economic development

    OpenAIRE

    Daphne A. Kenyon; Adam H. Langley; Bethany P. Paquin

    2013-01-01

    To make property-tax incentives for business more effective, do not approve every incentive request, target use of incentives, avoid incentive wars, cooperate with surrounding localities, and conduct regular evaluations.

  15. Biofuel excision and the viability of ethanol production in the Green Triangle, Australia

    International Nuclear Information System (INIS)

    Rodriguez, Luis C.; May, Barrie; Herr, Alexander; Farine, Damien; O'Connell, Deborah

    2011-01-01

    The promotion and use of renewable energy sources are established priorities worldwide as a way to reduce emissions of Greenhouse Gases and promote energy security. Australia is committed to reach a target of 350 ML of biofuels per year by 2010, and incentives targeted to producers and consumers have been placed. These incentives include zero excise until 2011 for the ethanol produced in Australia and gradual increase of the taxation rates reaching the full excise of 0.125 AUD per litre by 2015. This paper analyses the viability of the second generation ethanol industry in the Green Triangle, one of the most promising Australian regions for biomass production, by comparing the energy adjusted pump prices of petrol and the produced ethanol under different taxation rates and forecasted oil prices. Major findings suggest that under the current conditions of zero fuel excise and oil prices around 80US$ per barrel ethanol production is viable using biomass with a plant gate cost of up to 74 AUD per ton. Moreover, the forecasted increase in oil prices have a higher impact on the price of petrol than the increased ethanol excise on the pump price of the biofuel. Thus, by 2016 feedstock with a plant gate cost of up to 190 AUD per ton might be used for ethanol production, representing a flow of 1.7 million tons of biomass per year potentially mitigating 1.2 million tons of CO 2 by replacing fossil fuels with ethanol. - Research highlights: →We assessed the potential for ethanol production in the Green Triangle. → Despite of increased ethanol taxation, higher oil prices promote ethanol production. → Currently, ethanol from biomass with a plant gate cost of up to 74 AUD/ton is viable. →Forecasted oil prices suggest biomass of 190 AUD/ton might be used by 2016.

  16. Canadian ethanol retailers' directory

    International Nuclear Information System (INIS)

    1998-06-01

    This listing is a directory of all ethanol-blended gasoline retailers in Quebec, Ontario, Manitoba, Saskatchewan, Alberta, British Columbia, and the Yukon. The listing includes the name and address of the retailer. Bulk purchase facilities of ethanol-blended fuels are also included, but in a separate listing

  17. Canada's ethanol retail directory

    International Nuclear Information System (INIS)

    1996-11-01

    A directory was published listing all ethanol-blended gasoline retailers in Quebec, Ontario, Manitoba, Saskatchewan, Alberta, British Columbia, and the Yukon. The listings include the name and address of the retailer. A list of bulk purchase facilities of ethanol-blended fuels is also included

  18. Ionic liquid processing of cellulose.

    Science.gov (United States)

    Wang, Hui; Gurau, Gabriela; Rogers, Robin D

    2012-02-21

    Utilization of natural polymers has attracted increasing attention because of the consumption and over-exploitation of non-renewable resources, such as coal and oil. The development of green processing of cellulose, the most abundant biorenewable material on Earth, is urgent from the viewpoints of both sustainability and environmental protection. The discovery of the dissolution of cellulose in ionic liquids (ILs, salts which melt below 100 °C) provides new opportunities for the processing of this biopolymer, however, many fundamental and practical questions need to be answered in order to determine if this will ultimately be a green or sustainable strategy. In this critical review, the open fundamental questions regarding the interactions of cellulose with both the IL cations and anions in the dissolution process are discussed. Investigations have shown that the interactions between the anion and cellulose play an important role in the solvation of cellulose, however, opinions on the role of the cation are conflicting. Some researchers have concluded that the cations are hydrogen bonding to this biopolymer, while others suggest they are not. Our review of the available data has led us to urge the use of more chemical units of solubility, such as 'g cellulose per mole of IL' or 'mol IL per mol hydroxyl in cellulose' to provide more consistency in data reporting and more insight into the dissolution mechanism. This review will also assess the greenness and sustainability of IL processing of biomass, where it would seem that the choices of cation and anion are critical not only to the science of the dissolution, but to the ultimate 'greenness' of any process (142 references).

  19. IMPROVEMENT OF BIOFUEL ETHANOL RECOVERY USING THE PERVAPORATION SEPARATION TECHNIQUE

    Energy Technology Data Exchange (ETDEWEB)

    Nilufer Durmaz Hilmioglu [Kocaeli University Chemical Engineering Department Veziroglu Campus, Kocaeli (Turkey)

    2008-09-30

    The climatic impact of carbon dioxide emissions from the burning of fossil fuels have become a major problem. The production of renewable biofuels from biomass has received increasing attention. Because of the economic and environmental benefits of fuel ethanol's use it is considered one of the most important renewable fuels. In ethanol fermentations inhibition of the microorganism by ethanol limits the amount of substrate in the feed that can be converted. In a process high feed concentrations are desirable to minimize the flows. Such high feed concentrations can be realized in integrated processes in which ethanol is recovered by pervaporation from the fermentation broth as it is formed. The hybrid process is an attractive process to increase ethanol production economics and to decrease environmental pollution. The separaiton of alcohol from mixtures with ethanol produced by fermentation is usually carried out by distillation and the energy consumption is very high when azeotropic concentration is reached, which corresponds to 5% water in ethanol/water mixture. The pervaporation process provides an economical alternative to the existing distillation technique. A continous recovery of alcohol could be achieved by using the pervaporation process during fermentation, making the process more energy efficient. In this work, for the purposes of membrane material development for pervaporation; zeolite filled and unfilled cellulose acetate membranes were prepared. Zeolite types were 4A, 13X. The effect of incorporation of nano-sized zeolites prepared in a colloidal form in membranes was also investigated. From the sorption tests it is concluded that, ethanol/water azeotropy can be breaked by pervaporation.

  20. Incentives – Effectiveness and efficiency

    Directory of Open Access Journals (Sweden)

    Björn Hinderlich

    2014-03-01

    Full Text Available This paper covers the question if and how incentive schemes work evaluated by their impact on company performance (market capitalization and profit before tax. Based on a unique data set for German executive directors of DAX companies it can be proved that neither short (STI nor long term incentives (LTI plans necessarily support the company success. It rather depends on the efficiency of each plan, i. e. on its design. Special attention has to be paid on target setting. Short term focused objectives often miss their targets, whereas long term oriented objectives significantly support the company success. To solve the prisoner’s dilemma between employers and employees by a quasi-endless game, additional measures may be helpful, such as share ownership guidelines.

  1. Extrinsic incentives and tax compliance

    OpenAIRE

    Sour, Laura; Gutiérrez Andrade, Miguel Ángel

    2011-01-01

    This paper models the impact of extrinsic incentives in a tax compliance model. It also provides experimental evidence that confirms the existence of a positive relationship between rewards and tax compliance. If individuals are audited, rewards for honest taxpayers are effective in increasing the level of tax compliance. These results are particularly relevant in countries where there is little respect for tax law since rewards can contribute to crowding in the intrinsic motivation to comply.

  2. Accounting Conservatism and Managerial Incentives

    OpenAIRE

    Young K. Kwon

    2005-01-01

    There are two sources of agency costs under moral hazard: (1) distortions in incentive contracts and (2) implementation of suboptimal decisions. In the accounting literature, the relation between conservative accounting and agency costs of type (1) has received considerable attention (cf. Watts 2002). However, little appears to be known about the effects of accounting conservatism on agency costs of type (2) or trade-offs between agency costs of types (1) and (2). The purpose of this study is...

  3. An Incentive Theory of Matching

    OpenAIRE

    Brown, Alessio J. G.; Merkl, Christian; Snower, Dennis J.

    2010-01-01

    This paper examines the labour market matching process by distinguishing its two component stages: the contact stage, in which job searchers make contact with employers and the selection stage, in which they decide whether to match. We construct a theoretical model explaining two-sided selection through microeconomic incentives. Firms face adjustment costs in responding to heterogeneous variations in the characteristics of workers and jobs. Matches and separations are described through firms'...

  4. Kinetic modeling and dynamic analysis of simultaneous saccharification and fermentation of cellulose to bioethanol

    International Nuclear Information System (INIS)

    Shadbahr, Jalil; Khan, Faisal; Zhang, Yan

    2017-01-01

    Highlights: • Deeper understanding of saccharification and fermentation process. • A new kinetic model for dynamic analysis of the simultaneous saccharification and fermentation. • Testing and validation of kinetic model. - Abstract: Kinetic modeling and dynamic analysis of the simultaneous saccharification and fermentation (SSF) of cellulose to ethanol was carried out in this study to determine the key reaction kinetics parameters and product inhibition features of the process. To obtain the more reliable kinetic parameters which can be applied for a wide range of operating conditions, batch SSF experiments were carried out at three enzyme loadings (10, 15 and 20 FPU/g cellulose) and two levels of initial concentrations of fermentable sugars (glucose and mannose). Results indicated that the maximum ethanol yield and concentration were achieved at high level of sugar concentrations with intermediate enzyme loading (15 FPU/g cellulose). Dynamic analysis of the acquired experimental results revealed that cellulase inhibition by cellobiose plays the most important role at high level of enzyme loading and low level of initial sugar concentrations. The inhibition of glucose becomes significant when high concentrations of sugars were present in the feedstock. Experimental results of SSF process also reveal that an efficient mixing between the phases helps to improve the ethanol yield significantly.

  5. Electron beam application as pre treatment of sugar cane bagasse to enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    Cardoso, Vanessa Miguel

    2008-01-01

    Due to increasing worldwide shortage of food and energy sources, sugarcane bagasse has been considered as a substrate for single cell protein, animal feed, and renewable energy production. Sugarcane bagasse generally contain up to 45% glucose polymer cellulose, much of which is in a crystalline structure, 40% hemicelluloses, an amorphous polymer usually composed of xylose, arabinose, galactose, glucose, and mannose and 20% lignin, which cannot be easily separated into readily usable components due to their recalcitrant nature. Pure cellulose is readily depolymerised by radiation, but in biomass the cellulose is intimately bonded with lignin, that protect it from radiation effects. The objective of this study was the evaluation of the electron beam irradiation efficiency as a pre-treatment to enzymatic hydrolysis of cellulose in order to facilitate its fermentation and improves the production of ethanol biofuel. Samples of sugarcane bagasse were obtained in sugar/ethanol Mill sited in Piracicaba, Brazil, and were irradiated using Radiation Dynamics Electron Beam Accelerator with 1,5 MeV energy and 37 kW, in batch systems. The applied absorbed doses of the fist sampling, Bagasse A, were 20 kGy, 50 kGy, 10 0 kGy and 200 kGy. After the evaluation the preliminary obtained results, it was applied lower absorbed doses in the second assay: 5 kGy, 10 kGy, 20 kGy, 30 kGy, 50 kGy, 70 kGy, 100 kGy and 150 kGy. The electron beam processing took to changes in the sugarcane bagasse structure and composition, lignin and cellulose cleavage. The yield of enzymatic hydrolyzes of cellulose in. (author)

  6. Incentives for reporting disease outbreaks.

    Directory of Open Access Journals (Sweden)

    Ramanan Laxminarayan

    Full Text Available BACKGROUND: Countries face conflicting incentives to report infectious disease outbreaks. Reports of outbreaks can prompt other countries to impose trade and travel restrictions, which has the potential to discourage reporting. However, reports can also bring medical assistance to contain the outbreak, including access to vaccines. METHODS: We compiled data on reports of meningococcal meningitis to the World Health Organization (WHO from 54 African countries between 1966 and 2002, a period is marked by two events: first, a large outbreak reported from many countries in 1987 associated with the Hajj that resulted in more stringent requirements for meningitis vaccination among pilgrims; and second, another large outbreak in Sub-Saharan Africa in 1996 that led to a new international mechanism to supply vaccines to countries reporting a meningitis outbreak. We used fixed-effects regression modeling to statistically estimate the effect of external forcing events on the number of countries reporting cases of meningitis to WHO. FINDINGS: We find that the Hajj vaccination requirements started in 1988 were associated with reduced reporting, especially among countries with relatively fewer cases reported between 1966 and 1979. After the vaccine provision mechanism was in place in 1996, reporting among countries that had previously not reported meningitis outbreaks increased. INTERPRETATION: These results indicate that countries may respond to changing incentives to report outbreaks when they can do so. In the long term, these incentives are likely to be more important than surveillance assistance in prompt reporting of outbreaks.

  7. The cellulose synthase companion proteins act non-redundantly with CELLULOSE SYNTHASE INTERACTING1/POM2 and CELLULOSE SYNTHASE 6

    OpenAIRE

    Endler, Anne; Schneider, Rene; Kesten, Christopher; Lampugnani, Edwin R.; Persson, Staffan

    2016-01-01

    Cellulose is a cell wall constituent that is essential for plant growth and development, and an important raw material for a range of industrial applications. Cellulose is synthesized at the plasma membrane by massive cellulose synthase (CesA) complexes that track along cortical microtubules in elongating cells of Arabidopsis through the activity of the protein CELLULOSE SYNTHASE INTERACTING1 (CSI1). In a recent study we identified another family of proteins that also are associated with the ...

  8. Technological trends, global market, and challenges of bio-ethanol production.

    Science.gov (United States)

    Mussatto, Solange I; Dragone, Giuliano; Guimarães, Pedro M R; Silva, João Paulo A; Carneiro, Lívia M; Roberto, Inês C; Vicente, António; Domingues, Lucília; Teixeira, José A

    2010-01-01

    Ethanol use as a fuel additive or directly as a fuel source has grown in popularity due to governmental regulations and in some cases economic incentives based on environmental concerns as well as a desire to reduce oil dependency. As a consequence, several countries are interested in developing their internal market for use of this biofuel. Currently, almost all bio-ethanol is produced from grain or sugarcane. However, as this kind of feedstock is essentially food, other efficient and economically viable technologies for ethanol production have been evaluated. This article reviews some current and promising technologies for ethanol production considering aspects related to the raw materials, processes, and engineered strains development. The main producer and consumer nations and future perspectives for the ethanol market are also presented. Finally, technological trends to expand this market are discussed focusing on promising strategies like the use of microalgae and continuous systems with immobilized cells. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. Cellulose nanocrystal properties and their applications

    Directory of Open Access Journals (Sweden)

    mahdi jonoobi

    2015-05-01

    Full Text Available The main purpose of this work is to provide an overview of recent research in the area of cellulose nonmaterials production from different sources. Due to their abundance, their renewability, high strength and stiffness, being eco-friendly, and low weight; numerous studies have been reported on the isolation of cellulose nanomaterials from different cellulosic sources and their use in high performance applications. This work covers an introduction into the nano cellulose definition as well as used methods for isolation of nanomaterials (nanocrystals from various sources. The rod-like cellulose nanocrystals (CNC can be isolated from sources like wood, plant fibers, agriculture and industrial bio residues, tunicates, and bacterial cellulose using acid hydrolysis process. Following this, the paper focused on characterization methods, materials properties and structure. The current review is a comprehensive literature regarding the nano cellulose isolation and demonstrates the potential of cellulose nanomaterials to be used in a wide range of high-tech applications.

  10. Cellulose multilayer Membranes manufacture with Ionic liquid

    KAUST Repository

    Livazovic, Sara; Li, Z.; Behzad, Ali Reza; Peinemann, Klaus-Viktor; Nunes, Suzana Pereira

    2015-01-01

    and ultrafiltration, with thin selective layers of naturally available cellulose has been hampered by the availability of non-aggressive solvents. We propose the manufacture of cellulose membranes based on two approaches: (i) silylation, coating from solutions

  11. Cellulose nanocrystal submonolayers by spin coating

    NARCIS (Netherlands)

    Kontturi, E.J.; Johansson, L.S.; Kontturi, K.S.; Ahonen, P.; Thune, P.C.; Laine, J.

    2007-01-01

    Dilute concentrations of cellulose nanocrystal solutions were spin coated onto different substrates to investigate the effect of the substrate on the nanocrystal submonolayers. Three substrates were probed: silica, titania, and amorphous cellulose. According to atomic force microscopy (AFM) images,

  12. Characterization of Cellulose Synthesis in Plant Cells

    Directory of Open Access Journals (Sweden)

    Samaneh Sadat Maleki

    2016-01-01

    Full Text Available Cellulose is the most significant structural component of plant cell wall. Cellulose, polysaccharide containing repeated unbranched β (1-4 D-glucose units, is synthesized at the plasma membrane by the cellulose synthase complex (CSC from bacteria to plants. The CSC is involved in biosynthesis of cellulose microfibrils containing 18 cellulose synthase (CesA proteins. Macrofibrils can be formed with side by side arrangement of microfibrils. In addition, beside CesA, various proteins like the KORRIGAN, sucrose synthase, cytoskeletal components, and COBRA-like proteins have been involved in cellulose biosynthesis. Understanding the mechanisms of cellulose biosynthesis is of great importance not only for improving wood production in economically important forest trees to mankind but also for plant development. This review article covers the current knowledge about the cellulose biosynthesis-related gene family.

  13. Characterization of Cellulose Synthesis in Plant Cells

    Science.gov (United States)

    Maleki, Samaneh Sadat; Mohammadi, Kourosh; Ji, Kong-shu

    2016-01-01

    Cellulose is the most significant structural component of plant cell wall. Cellulose, polysaccharide containing repeated unbranched β (1-4) D-glucose units, is synthesized at the plasma membrane by the cellulose synthase complex (CSC) from bacteria to plants. The CSC is involved in biosynthesis of cellulose microfibrils containing 18 cellulose synthase (CesA) proteins. Macrofibrils can be formed with side by side arrangement of microfibrils. In addition, beside CesA, various proteins like the KORRIGAN, sucrose synthase, cytoskeletal components, and COBRA-like proteins have been involved in cellulose biosynthesis. Understanding the mechanisms of cellulose biosynthesis is of great importance not only for improving wood production in economically important forest trees to mankind but also for plant development. This review article covers the current knowledge about the cellulose biosynthesis-related gene family. PMID:27314060

  14. A Molecular Description of Cellulose Biosynthesis

    Science.gov (United States)

    McNamara, Joshua T.; Morgan, Jacob L.W.; Zimmer, Jochen

    2016-01-01

    Cellulose is the most abundant biopolymer on Earth, and certain organisms from bacteria to plants and animals synthesize cellulose as an extracellular polymer for various biological functions. Humans have used cellulose for millennia as a material and an energy source, and the advent of a lignocellulosic fuel industry will elevate it to the primary carbon source for the burgeoning renewable energy sector. Despite the biological and societal importance of cellulose, the molecular mechanism by which it is synthesized is now only beginning to emerge. On the basis of recent advances in structural and molecular biology on bacterial cellulose synthases, we review emerging concepts of how the enzymes polymerize glucose molecules, how the nascent polymer is transported across the plasma membrane, and how bacterial cellulose biosynthesis is regulated during biofilm formation. Additionally, we review evolutionary commonalities and differences between cellulose synthases that modulate the nature of the cellulose product formed. PMID:26034894

  15. Raman spectroscopy in the analysis of cellulose nanomaterials

    Science.gov (United States)

    Umesh P. Agarwal

    2017-01-01

    Cellulose nanomaterials (CNs) are new types of materials derived from celluloses and offer unique challenges and opportunities for Raman spectroscopic investigations. CNs can be classified into the categories of cellulose nanocrystals (CNCs, also known as cellulose whisker) and cellulose nanofibrils (CNFs, also known as nanofibrillated cellulose or NFCs) which when...

  16. Consolidated Bio-Processing of Cellulosic Biomass for Efficient Biofuel Production Using Yeast Consortium

    Science.gov (United States)

    Goyal, Garima

    Fossil fuels have been the major source for liquid transportation fuels for ages. However, decline in oil reserves and environmental concerns have raised a lot of interest in alternative and renewable energy sources. One promising alternative is the conversion of plant biomass into ethanol. The primary biomass feed stocks currently being used for the ethanol industry have been food based biomass (corn and sugar cane). However, interest has recently shifted to replace these traditional feed-stocks with more abundant, non-food based cellulosic biomass such as agriculture wastes (corn stover) or crops (switch grass). The use of cellulosic biomass as feed stock for the production of ethanol via bio-chemical routes presents many technical challenges not faced with the use of corn or sugar-cane as feed-stock. Recently, a new process called consolidated Bio-processing (CBP) has been proposed. This process combines simultaneous saccharification of lignocellulose with fermentation of the resulting sugars into a single process step mediated by a single microorganism or microbial consortium. Although there is no natural microorganism that possesses all properties of lignocellulose utilization and ethanol production desired for CBP, some bacteria and fungi exhibit some of the essential traits. The yeast Saccharomyces cerevisiae is the most attractive host organism for the usage of this strategy due to its high ethanol productivity at close to theoretical yields (0.51g ethanol/g glucose consumed), high osmo- and ethanol- tolerance, natural robustness in industrial processes, and ease of genetic manipulation. Introduction of the cellulosome, found naturally in microorganisms, has shown new directions to deal with recalcitrant biomass. In this case enzymes work in synergy in order to hydrolyze biomass more effectively than in case of free enzymes. A microbial consortium has been successfully developed, which ensures the functional assembly of minicellulosome on the yeast surface

  17. Radiation modification of cellulose pulps. Preparation of cellulose derivatives

    International Nuclear Information System (INIS)

    Iller, E.; Zimek, Z.; Stupinska, H.; Mikolajczyk, W; Starostka, P.

    2005-01-01

    One of the most common methods of cellulose pulp modification (activation) applied in the production process of cellulose derivatives is the treatment of the pulp with NaOH solutions leading to the formation of alkalicellulose. The product then undergoes a prolonged process of maturation by its storage under specific conditions. The goal of the process is lowering of the molecular weight of cellulose down to the level resulting from various technological requirements. The process is time-consuming and costly; besides, it requires usage of large-capacity technological vessels and produces considerable amounts of liquid waste. Therefore, many attempts have been made to limit or altogether eliminate the highly disadvantageous stage of cellulose treatment with lye. One of the alternatives proposed so far is the radiation treatment of the cellulose pulp. In the pulp exposed to an electron beam, the bonds between molecules of D-antihydroglucopiranoses loosen and the local crystalline lattice becomes destroyed. This facilitates the access of chemical reagents to the inner structure of the cellulose and, in consequence, eliminates the need for the prolonged maturation of alkalicellulose, thus reducing the consumption of chemicals by the whole process. Research aimed at the application of radiation treatment of cellulose pulp for the production of cellulose derivatives has been conducted by a number of scientific institutions including the Institute of Nuclear Chemistry and Technology, Institute of Biopolymers and Chemical Fibres, and Pulp and Paper Research Institute. For the investigations and assessment of the molecular, hypermolecular, morphologic properties and the chemical reactivity, cellulose pulps used for chemical processing, namely Alicell, Borregaard and Ketchikan, as well as paper pulps made from pine and birch wood were selected. The selected cellulose pulps were exposed to an electron beam with an energy of 10 MeV generated in a linear electron accelerator

  18. Clostridium thermocellum ATCC27405 transcriptomic, metabolomic and proteomic profiles after ethanol stress

    Directory of Open Access Journals (Sweden)

    Yang Shihui

    2012-07-01

    Full Text Available Abstract Background Clostridium thermocellum is a candidate consolidated bioprocessing biocatalyst, which is a microorganism that expresses enzymes for both cellulose hydrolysis and its fermentation to produce fuels such as lignocellulosic ethanol. However, C. thermocellum is relatively sensitive to ethanol compared to ethanologenic microorganisms such as yeast and Zymomonas mobilis that are used in industrial fermentations but do not possess native enzymes for industrial cellulose hydrolysis. Results In this study, C. thermocellum was grown to mid-exponential phase and then treated with ethanol to a final concentration of 3.9 g/L to investigate its physiological and regulatory responses to ethanol stress. Samples were taken pre-shock and 2, 12, 30, 60, 120, and 240 min post-shock, and from untreated control fermentations for systems biology analyses. Cell growth was arrested by ethanol supplementation with intracellular accumulation of carbon sources such as cellobiose, and sugar phosphates, including fructose-6-phosphate and glucose-6-phosphate. The largest response of C. thermocellum to ethanol shock treatment was in genes and proteins related to nitrogen uptake and metabolism, which is likely important for redirecting the cells physiology to overcome inhibition and allow growth to resume. Conclusion This study suggests possible avenues for metabolic engineering and provides comprehensive, integrated systems biology datasets that will be useful for future metabolic modeling and strain development endeavors.

  19. Properties of microcrystalline cellulose obtained from coconut ...

    African Journals Online (AJOL)

    The study revealed that the cellulose material compares favourably with Avicel PH 101 as well as official requirement specified in the British Pharmacopoeia 1993 for microcrystalline cellulose. Keywords: Coconut fruit fibre, microcrystalline cellulose, powder properties. Journal of Pharmacy and Bioresources Vol. 3 (1) 2006: ...

  20. Method of producing thin cellulose nitrate film

    International Nuclear Information System (INIS)

    Lupica, S.B.

    1975-01-01

    An improved method for forming a thin nitrocellulose film of reproducible thickness is described. The film is a cellulose nitrate film, 10 to 20 microns in thickness, cast from a solution of cellulose nitrate in tetrahydrofuran, said solution containing from 7 to 15 percent, by weight, of dioctyl phthalate, said cellulose nitrate having a nitrogen content of from 10 to 13 percent

  1. Bioengineering cellulose-hemicellulose networks in plants

    NARCIS (Netherlands)

    Obembe, O.

    2006-01-01

    The interactions between cellulose and hemicellulose in the cell walls are important in the industrial application of the cellulose (natural) fibres. We strive to modify these interactions (i) by interfering with cellulose biosynthesis and (ii) by direct interference of the

  2. Regioselective Synthesis of Cellulose Ester Homopolymers

    Science.gov (United States)

    Daiqiang Xu; Kristen Voiges; Thomas Elder; Petra Mischnick; Kevin J. Edgar

    2012-01-01

    Regioselective synthesis of cellulose esters is extremely difficult due to the small reactivity differences between cellulose hydroxyl groups, small differences in steric demand between acyl moieties of interest, and the difficulty of attaching and detaching many protecting groups in the presence of cellulose ester moieties without removing the ester groups. Yet the...

  3. 21 CFR 172.870 - Hydroxypropyl cellulose.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Hydroxypropyl cellulose. 172.870 Section 172.870... CONSUMPTION Multipurpose Additives § 172.870 Hydroxypropyl cellulose. The food additive hydroxypropyl cellulose may be safely used in food, except standardized foods that do not provide for such use, in...

  4. Cellulose nanomaterials review: structure, properties and nanocomposites

    Science.gov (United States)

    Robert J. Moon; Ashlie Martini; John Nairn; John Simonsen; Jeff Youngblood

    2011-01-01

    This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The...

  5. The Effect of Incentives and Meta-incentives on the Evolution of Cooperation

    OpenAIRE

    Okada, Isamu; Yamamoto, Hitoshi; Toriumi, Fujio; Sasaki, Tatsuya

    2015-01-01

    Although positive incentives for cooperators and/or negative incentives for free-riders in social dilemmas play an important role in maintaining cooperation, there is still the outstanding issue of who should pay the cost of incentives. The second-order free-rider problem, in which players who do not provide the incentives dominate in a game, is a well-known academic challenge. In order to meet this challenge, we devise and analyze a meta-incentive game that integrates positive incentives (re...

  6. Speichim cuts ethanol energy

    Energy Technology Data Exchange (ETDEWEB)

    1981-05-08

    France's Speichim has reported low-pressure steam consumption of only 0.7kg/l in the production of industrial-grade ethanol. Mechanical compression of distillation vapours can reduce this energy demand even more.

  7. Ionic Liquids and Cellulose: Dissolution, Chemical Modification and Preparation of New Cellulosic Materials

    Science.gov (United States)

    Isik, Mehmet; Sardon, Haritz; Mecerreyes, David

    2014-01-01

    Due to its abundance and a wide range of beneficial physical and chemical properties, cellulose has become very popular in order to produce materials for various applications. This review summarizes the recent advances in the development of new cellulose materials and technologies using ionic liquids. Dissolution of cellulose in ionic liquids has been used to develop new processing technologies, cellulose functionalization methods and new cellulose materials including blends, composites, fibers and ion gels. PMID:25000264

  8. Ionic Liquids and Cellulose: Dissolution, Chemical Modification and Preparation of New Cellulosic Materials

    Directory of Open Access Journals (Sweden)

    Mehmet Isik

    2014-07-01

    Full Text Available Due to its abundance and a wide range of beneficial physical and chemical properties, cellulose has become very popular in order to produce materials for various applications. This review summarizes the recent advances in the development of new cellulose materials and technologies using ionic liquids. Dissolution of cellulose in ionic liquids has been used to develop new processing technologies, cellulose functionalization methods and new cellulose materials including blends, composites, fibers and ion gels.

  9. Net-Immobilization of β-glucosidase on Nonwoven Fabrics to Lower the Cost of “Cellulosic Ethanol” and Increase Cellulose Conversions

    Science.gov (United States)

    Zhu, Xing; He, Bin; Zhao, Changwen; Fan, Rong; Zhang, Lihua; Wang, Guan; Ma, Yuhong; Yang, Wantai

    2016-03-01

    The main limitation preventing the use of enzymatic cellulosic ethanol in industrial production is its higher cost which is mainly due to the elevated price of β-glucosidase (BG). Herein, we report on a simple strategy for the in-situ encapsulation of BG for repeated cellulosic ethanol production. In this strategy, BG was net-immobilized into a poly(ethylene glycol) (PEG) net-cloth layer on a PP nonwoven fabric by way of the visible light-induced surface controlled/living graft cross-linking polymerization. The visible light and mild reaction conditions could ensure the activity retention of BG during immobilization, while the non-swelling uniform net-mesh formed by living cross-linking polymerization could prevent the leakage of BG effectively (at the immobilization rate of more than 98.6% and the leakage rate of only 0.4%). When the BG-loaded fabric was used in combination with free cellulase (CEL), the results of the catalytic reaction demonstrated that these BG-loaded fabrics could not only give a 40% increase in cellulose conversions but also be reused for more than fifteen batches without losing the activity. These BG-loaded fabrics with characteristics including easy separation, excellent operation stability, a low cost of the polymeric matrix and a simple fabrication process are particularly interesting for a future bio-fuel production strategy.

  10. Development of microorganisms for cellulose-biofuel consolidated bioprocessings: metabolic engineers’ tricks

    Directory of Open Access Journals (Sweden)

    Roberto Mazzoli

    2012-10-01

    Full Text Available Cellulose waste biomass is the most abundant and attractive substrate for "biorefinery strategies" that are aimed to produce high-value products (e.g. solvents, fuels, building blocks by economically and environmentally sustainable fermentation processes. However, cellulose is highly recalcitrant to biodegradation and its conversion by biotechnological strategies currently requires economically inefficient multistep industrial processes. The need for dedicated cellulase production continues to be a major constraint to cost-effective processing of cellulosic biomass.Research efforts have been aimed at developing recombinant microorganisms with suitable characteristics for single step biomass fermentation (consolidated bioprocessing, CBP. Two paradigms have been applied for such, so far unsuccessful, attempts: a “native cellulolytic strategies”, aimed at conferring high-value product properties to natural cellulolytic microorganisms; b “recombinant cellulolytic strategies”, aimed to confer cellulolytic ability to microorganisms exhibiting high product yields and titers.By starting from the description of natural enzyme systems for plant biomass degradation and natural metabolic pathways for some of the most valuable product (i.e. butanol, ethanol, and hydrogen biosynthesis, this review describes state-of-the-art bottlenecks and solutions for the development of recombinant microbial strains for cellulosic biofuel CBP by metabolic engineering. Complexed cellulases (i.e. cellulosomes benefit from stronger proximity effects and show enhanced synergy on insoluble substrates (i.e. crystalline cellulose with respect to free enzymes. For this reason, special attention was held on strategies involving cellulosome/designer cellulosome-bearing recombinant microorganisms.

  11. Enzymatic hydrolysis of cellulose dissolved in N-methyl morpholine oxide/water solutions.

    Science.gov (United States)

    Ramakrishnan, S; Collier, J; Oyetunji, R; Stutts, B; Burnett, R

    2010-07-01

    In situ hydrolysis of cellulose (dissolving pulp) in N-methyl morpholine oxide (NMMO) solutions by commercially available Accellerase1000 is carried out. The yield of reducing sugars is followed as a function of time at three different temperatures and four different enzyme loadings to study the effect of system parameters on enzymatic hydrolysis. Initial results show that rates of hydrolysis of cellulose and yields of reducing sugars in the presence of NMMO-water is superior initially (ratio of initial reaction rates approximately 4) and comparable to that of regenerated cellulose (for times greater than 5h) when suspended in aqueous solutions. The usage of Accellerase1000 results predominantly in the formation of glucose with minimal amounts of cellobiose. This study proves the ability of cellulases to remain active in NMMO to carry out an in situ saccharification of cellulose thus eliminating the need to recover regenerated cellulose. Thus this work will form the basis for developing a continuous process for conversion of biomass to hydrogen, ethanol and other hydrocarbons. Copyright 2009 Elsevier Ltd. All rights reserved.

  12. Water Conservation and Economic Incentives

    Science.gov (United States)

    Narayanan, M.

    2016-12-01

    Water has played a vital role in the progress of human civilization throughout history. Both agriculture based economics as well as industry based economics totally rely upon water for survival and prosperity. Water could be a limiting factor in dictating day-to-day human activities and as such one should learn to live within the limits of available natural resources. Most of the water on this earth is either salty or undrinkable. Only one percent of world's water is available for all the needs of human civilization. This includes human personal household needs, community activities, agriculture, industry, plant and animal life sustenance. The supply of usable fresh water is finite and the per capita consumption of fresh water needs to be reduced in particularly in some selected regions of this world. The United States consumes about 450 billion gallons of water every day. The U.S. daily average of water pumped by public water supply systems is 185 gallons per person. The biggest water gobbler in a household is the lawn. Typically, at least 50% of water consumed by households is used outdoors. Even inside a house, bathroom facilities claim nearly 75% of the water used. Here is a short list of economic Incentives that may help water conservation. (1) Providing rebates, refunds or other economic incentives to those consumers that are willing to change to modern technological methods. Examples include, but not limited to energy efficient washing machines, low-flush toilets and improved shower head designs. (2) Communities should provide economic incentives to limit the type and size of landscaping. (3) Need, necessity and nature of outdoor water use could be restricted whenever possible. (4) Sprinkler ban may be deemed appropriate in extreme cases. (5) Set up hotlines that can help penalize those that ignore water conservation guidelines. (6) Incorporating water conservation monitors. References: http://www.nrdc.org/water/http://www.ecy.wa.gov/programs/wr/ws/wtrcnsv.htmlhttp://www.sscwd.org/tips.html

  13. Environmental benefits of ethanol

    International Nuclear Information System (INIS)

    1998-11-01

    The environmental benefits of ethanol blended fuels in helping to reduce harmful emissions into the atmosphere are discussed. The use of oxygenated fuels such as ethanol is one way of addressing air pollution concerns such as ozone formation. The state of California has legislated stringent automobile emissions standards in an effort to reduce emissions that contribute to the formation of ground-level ozone. Several Canadian cities also record similar hazardous exposures to carbon monoxide, particularly in fall and winter. Using oxygenated fuels such as ethanol, is one way of addressing the issue of air pollution. The net effect of ethanol use is an overall decrease in ozone formation. For example, use of a 10 per cent ethanol blend results in a 25-30 per cent reduction in carbon monoxide emissions by promoting a more complete combustion of the fuel. It also results in a 6-10 per cent reduction of carbon dioxide, and a seven per cent overall decrease in exhaust VOCs (volatile organic compounds). The environmental implications of feedstock production associated with the production of ethanol for fuel was also discussed. One of the Canadian government's initiatives to address the climate change challenge is its FleetWise initiative, in which it has agreed to a phased-in acquisition of alternative fuel vehicles by the year 2005. 9 refs

  14. Physicotechnical, spectroscopic and thermogravimetric properties of powdered cellulose and microcrystalline cellulose derived from groundnut shells

    Directory of Open Access Journals (Sweden)

    Chukwuemeka P. Azubuike

    2012-09-01

    Full Text Available α-Cellulose and microcrystalline cellulose powders, derived from agricultural waste products, that have for the pharmaceutical industry, desirable physical (flow properties were investigated. α–Cellulose (GCN was extracted from groundnut shell (an agricultural waste product using a non-dissolving method based on inorganic reagents. Modification of this α -cellulose was carried out by partially hydrolysing it with 2N hydrochloric acid under reflux to obtain microcrystalline cellulose (MCGN. The physical, spectroscopic and thermal properties of the derived α-cellulose and microcrystalline cellulose powders were compared with Avicel® PH 101, a commercial brand of microcrystalline cellulose (MCCA, using standard methods. X-ray diffraction and infrared spectroscopy analysis showed that the α-cellulose had lower crystallinity. This suggested that treatment with 2N hydrochloric acid led to an increase in the crystallinity index. Thermogravimetric analysis showed quite similar thermal behavior for all cellulose samples, although the α-cellulose had a somewhat lower stability. A comparison of the physical properties between the microcrystalline celluloses and the α-cellulose suggests that microcrystalline cellulose (MCGN and MCCA might have better flow properties. In almost all cases, MCGN and MCCA had similar characteristics. Since groundnut shells are agricultural waste products, its utilization as a source of microcrystalline cellulose might be a good low-cost alternative to the more expensive commercial brand.

  15. Incentive Ratios of Fisher Markets

    DEFF Research Database (Denmark)

    Chen, Ning; Deng, Xuaitue; Zhang, Hongyang

    2012-01-01

    In a Fisher market, a market maker sells m items to n potential buyers. The buyers submit their utility functions and money endowments to the market maker, who, upon receiving submitted information, derives market equilibrium prices and allocations of its items. While agents may benefit...... by misreporting their private information, we show that the percentage of improvement by a unilateral strategic play, called incentive ratio, is rather limited—it is less than 2 for linear markets and at most $e^{1/e}\\thickapprox 1.445$ for Cobb-Douglas markets. We further prove that both ratios are tight....

  16. Incentives for improvement of CANDU

    International Nuclear Information System (INIS)

    Hart, R.S.; Dunn, J.T.; Finlay, R.B.

    1988-12-01

    CANDU is a relatively young technology which has demonstrated many achievements as an electrical power generation system. These achievements include an unsurpassed safety record, high annual and lifetime capacity factors, low electricity cost and a broad range of other performance strengths which together indicate that the CANDU technology is fundamentally sound. Known capabilities not yet fully exploited, such as advanced fuel cycle options, indicate that CANDU technology will continue to pay strong dividends on research, development and design investment. This provides a strong incentive for the improvement of CANDU on a continuing basis

  17. Market incentives and pharmaceutical innovation.

    Science.gov (United States)

    Yin, Wesley

    2008-07-01

    I study the impact of the Orphan Drug Act (ODA), which established tax incentives for rare disease drug development. I examine the flow of new clinical drug trials for a large set of rare diseases. Among more prevalent rare diseases, the ODA led to a significant and sustained increase in new trials. The impact for less prevalent rare diseases was limited to an increase in the stock of drugs. Tax credits can stimulate R & D; yet because they leave revenue margins unaffected, tax credits appear to have a more limited impact on private innovation in markets with smaller revenue potential.

  18. Incentives in Supply Function Equilibrium

    DEFF Research Database (Denmark)

    Vetter, Henrik

    2014-01-01

    The author analyses delegation in homogenous duopoly under the assumption that the firm-managers compete in supply functions. In supply function equilibrium, managers’ decisions are strategic complements. This reverses earlier findings in that the author finds that owners give managers incentives...... to act in an accommodating way. As a result, optimal delegation reduces per-firm output and increases profits to above-Cournot profits. Moreover, in supply function equilibrium the mode of competition is endogenous. This means that the author avoids results that are sensitive with respect to assuming...

  19. Goal- and signal-directed incentive: conditioned approach, seeking, and consumption established with unsweetened alcohol in rats.

    Science.gov (United States)

    Krank, Marvin D; O'Neill, Susan; Squarey, Kyna; Jacob, Jackie

    2008-02-01

    Many theories of addictive behavior propose that cues signaling drug administration influence the likelihood of drug-taking and drug-seeking behavior. We investigated the behavioral impact of cues associated with unsweetened ethanol and their interaction with responding maintained by ethanol self-administration. Our goal was to establish the influence of such cues on ethanol seeking. The experiment used a matching contingency and saccharin-fading procedure to establish equal levels of responding to two spatially distinct levers using unsweetened 10% ethanol solution. After ethanol self-administration was established, a brief cue light located alternately over each lever location was either paired or unpaired (control) with the opportunity to consume the same ethanol solution. Finally, self-administration was re-established, and the effect of the cue was measured in a transfer design. The reaction to lights paired with the opportunity to ingest unsweetened ethanol had three main effects: (1) induction of operant behavior reinforced by ethanol, (2) stimulation of ethanol-seeking behavior (drinker entries), and (3) cue-directed approach and contact behavior (i.e. autoshaping or sign-tracking). Cue-directed behavior to the light interacted with choice behavior in a manner predicted by the location of the cue light, enhancing responding only when the approach response did not interfere with the operant response. These findings replicate and extend the effects of Pavlovian conditioning on ethanol-seeking and support-conditioned incentive theories of addictive behavior. Signals for ethanol influence spatial choice behavior and may be relevant to attentional bias shown to alcohol-associated stimuli in humans.

  20. Advancing cellulose-based nanotechnology

    Science.gov (United States)

    Theodore H. Wegner; Philip E. Jones

    2006-01-01

    Nanotechnology has applications across most economic sectors and allows the development of new enabling science with broad commercial potential. Cellulose and lignocellulose have great potential as nanomaterials because they are abundant, renewable, have a nanofibrillar structure, can be made multifunctional, and self-assemble into well-defined architectures. To...

  1. Ignition inhibitors for cellulosic materials

    International Nuclear Information System (INIS)

    Alvares, N.J.

    1976-01-01

    By exposing samples to various irradiance levels from a calibrated thermal radiation source, the ignition responses of blackened alpha-cellulose and cotton cloth with and without fire-retardant additives were compared. Samples treated with retardant compounds which showed the most promise were then isothermally pyrolyzed in air for comparisons between the pyrolysis rates. Alpha-cellulose samples containing a mixture of boric acid, borax, and ammonium di-hydrogen phosphate could not be ignited by irradiances up to 4.0 cal cm -2 s-1 (16.7 W/cm 2 ). At higher irradiances the specimens ignited, but flaming lasted only until the flammable gases were depleted. Cotton cloth containing a polymeric retardant with the designation THPC + MM was found to be ignition-resistant to all irradiances below 7.0 cal cm -2 s -1 (29.3 W/cm 2 ). Comparison of the pyrolysis rates of the retardant-treated alpha-cellulose and the retardant-treated cotton showed that the retardant mechanism is qualitatively the same. Similar ignition-response measurements were also made with specimens exposed to ionizing radiation. It was observed that gamma radiation results in ignition retardance of cellulose, while irradiation by neutrons does not

  2. Polyvinyl alcohol–cellulose composite

    Indian Academy of Sciences (India)

    We have made an attempt to prepare taste sensor material by using functionalized polymer without any lipid. PVA–cellulose composite has been modified to use as the sensor material. The research work covers polymer membrane preparation, morphology study and structural characterization of the membrane and study of ...

  3. On incentives for assurance of petroleum supply

    International Nuclear Information System (INIS)

    Osmundsen, Petter; Aven, Terje; Tomasgard, Asgeir

    2010-01-01

    Assurance of supply is a crucial objective for producers and consumers of oil and gas. A basic requirement to meet this objective is that producers and transmitters have sufficient economic incentives and capabilities to assure a desired degree of supply. The topic of this paper is to evaluate these incentives from a broad perspective. We examine economic trade-offs inherent in a delay of production, including reputational issues, as well as contract incentives for gas sellers, drilling companies, and oil service companies.

  4. Incentives for reducing emissions in Krakow

    International Nuclear Information System (INIS)

    Uberman, R.; Pierce, B.; Lazecki, A.

    1994-01-01

    This effort is identifying, specific incentives that may be used by Krakow city officials to encourage, residents to change the way they heat their homes and businesses in order to reduce pollution. This paper describes the incentives study for converting small coal or coke-fired boilers to gas in the Old Town area. A similar study looked at incentives for expanding the district heating system and future analyses will be performed for home stove options

  5. Incentives and cooperation in firms: Field evidence

    OpenAIRE

    Berger, Johannes; Herbertz, Claus; Sliwka, Dirk

    2011-01-01

    We empirically investigate the impact of incentive scheme structure on the degree of cooperation in firms using a unique and representative data set. Combining employee survey data with detailed firm level information on the relative importance of individual, team, and company performance for compensation, we find a significant positive relation between the intensity of team incentives and several survey measures of cooperation. Moreover, higher powered team incentives are associated with low...

  6. Irradiation effects in wood and cellulose

    International Nuclear Information System (INIS)

    McLaren, K.G.

    1976-01-01

    For cellulosic materials the predominant effect of high energy radiation is depolymerisation and degradation by chain scission, although there is some evidence that crosslinking or cellulose stabilisation can occur under certain conditions. When the cellulose is in the form of a natural product such as wood, where it is intimately associated with other polysaccharides, lignins, resins and gums, the effects of radiation can be significantly modified. Examination of cellulose produced by chemical pulping treatment of wood which had been previously given small doses of radiation, showed significant differences in the extent of cellulose depolymerisation with different wood species. The relevance of this work to the paper pulp industry will also be discussed. (author)

  7. INEQUALITY, INCENTIVES AND THE INTERPERSONAL TEST

    DEFF Research Database (Denmark)

    Lippert-Rasmussen, Kasper

    2008-01-01

    ABSTRACT This article defends three claims: (1) even if Rawls' difference principle permits incentives to induce talented people to be more productive, it does not follow that it permits inequalities; (2) the difference principle, when adequately specified, may in some circumstances permit incent...... incentives and allow that the worst off are not made as well off as they could be; and (3) an argument for incentives might pass Cohen's interpersonal test even if it is unsound and might not pass it even if it is sound. 1...

  8. Pattern of the rational worker incentive system

    Directory of Open Access Journals (Sweden)

    Kopytova A.V.

    2017-01-01

    Full Text Available The article presents a model of rational incentive system with the structure consisting of three blocks. The first block (financial incentives provides monetary compensation to a worker. The second block (stimulating by comfortable living conditions is aimed to regulate the quality of a worker’s life in and outside the place he works. The third block (non-financial incentives takes into account cultural and social worker’s needs. The proposed structure of incentive system provides the most comprehensive coverage to the employee’s needs and organizes them in the way accessible both for specialists of labor economics and human resource management and for ordinary workers.

  9. Incentives and intrinsic motivation in healthcare

    Directory of Open Access Journals (Sweden)

    Mikel Berdud

    2016-11-01

    Conclusions: The conclusions could act as a guide to support the optimal design of incentive policies and schemes within health organisations when healthcare professionals are intrinsically motivated.

  10. The roles of xylan and lignin in oxalic acid pretreated corncob during separate enzymatic hydrolysis and ethanol fermentation

    Science.gov (United States)

    Jae-Won Lee; Rita C.L.B. Rodrigues; Hyun Joo Kim; In-Gyu Choi; Thomas W. Jeffries

    2010-01-01

    High yields of hemicellulosic and cellulosic sugars are critical in obtaining economical conversion of agricultural residues to ethanol. To optimize pretreatment conditions, we evaluated oxalic acid loading rates, treatment temperatures and times in a 23 full factorial design. Response-surface analysis revealed an optimal oxalic acid pretreatment...

  11. Structure and engineering of celluloses.

    Science.gov (United States)

    Pérez, Serge; Samain, Daniel

    2010-01-01

    This chapter collates the developments and conclusions of many of the extensive studies that have been conducted on cellulose, with particular emphasis on the structural and morphological features while not ignoring the most recent results derived from the elucidation of unique biosynthetic pathways. The presentation of structural and morphological data gathered together in this chapter follows the historical development of our knowledge of the different structural levels of cellulose and its various organizational levels. These levels concern features such as chain conformation, chain polarity, chain association, crystal polarity, and microfibril structure and organization. This chapter provides some historical landmarks related to the evolution of concepts in the field of biopolymer science, which parallel the developments of novel methods for characterization of complex macromolecular structures. The elucidation of the different structural levels of organization opens the way to relating structure to function and properties. The chemical and biochemical methods that have been developed to dissolve and further modify cellulose chains are briefly covered. Particular emphasis is given to the facets of topochemistry and topoenzymology where the morphological features play a key role in determining unique physicochemical properties. A final chapter addresses what might be considered tomorrow's goal in amplifying the economic importance of cellulose in the context of sustainable development. Selected examples illustrate the types of result that can be obtained when cellulose fibers are no longer viewed as inert substrates, and when the polyhydroxyl nature of their surfaces, as well as their entire structural complexity, are taken into account. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Energy assessment of second generation (2G) ethanol production from wheat straw in Indian scenario.

    Science.gov (United States)

    Mishra, Archana; Kumar, Akash; Ghosh, Sanjoy

    2018-03-01

    Impact of second-generation ethanol (2G) use in transportation sector mainly depends upon energy efficiency of entire production process. The objective of present study was to determine energy efficiency of a potential lignocellulosic feedstock; wheat straw and its conversion into cellulosic ethanol in Indian scenario. Energy efficiency was determined by calculating Net energy ratio (NER), i.e. ratio of output energy obtained by ethanol and input energy used in ethanol production. Energy consumption and generation at each step is calculated briefly (11,837.35 MJ/ha during Indian dwarf irrigated variety of wheat crop production and 7.1148 MJ/kg straw during ethanol production stage). Total energy consumption is calculated as 8.2988 MJ/kg straw whereas energy generation from ethanol is 15.082 MJ/kg straw; resulting into NER > 1. Major portion of agricultural energy input is contributed by diesel and fertilisers whereas refining process of wheat straw feedstock to ethanol and by-products require mainly in the form of steam and electricity. On an average, 1671.8 kg water free ethanol, 930 kg lignin rich biomass (for combustion), and 561 kg C5-molasses (for fodder) per hectare are produced. Findings of this study, net energy ratio (1.81) and figure of merit (14.8028 MJ/nil kg carbon) proves wheat straw as highest energy efficient lignocellulosic feedstock for the country.

  13. Cellulose Nanomaterials in Water Treatment Technologies

    Science.gov (United States)

    Carpenter, Alexis Wells; de Lannoy, Charles François; Wiesner, Mark R.

    2015-01-01

    Cellulose nanomaterials are naturally occurring with unique structural, mechanical and optical properties. While the paper and packaging, automotive, personal care, construction, and textiles industries have recognized cellulose nanomaterials’ potential, we suggest cellulose nanomaterials have great untapped potential in water treatment technologies. In this review, we gather evidence of cellulose nanomaterials’ beneficial role in environmental remediation and membranes for water filtration, including their high surface area-to-volume ratio, low environmental impact, high strength, functionalizability, and sustainability. We make direct comparison between cellulose nanomaterials and carbon nanotubes (CNTs) in terms of physical and chemical properties, production costs, use and disposal in order to show the potential of cellulose nanomaterials as a sustainable replacement for CNTs in water treatment technologies. Finally, we comment on the need for improved communication and collaboration across the myriad industries invested in cellulose nanomaterials production and development to achieve an efficient means to commercialization. PMID:25837659

  14. Cellulose nanomaterials in water treatment technologies.

    Science.gov (United States)

    Carpenter, Alexis Wells; de Lannoy, Charles-François; Wiesner, Mark R

    2015-05-05

    Cellulose nanomaterials are naturally occurring with unique structural, mechanical and optical properties. While the paper and packaging, automotive, personal care, construction, and textiles industries have recognized cellulose nanomaterials' potential, we suggest cellulose nanomaterials have great untapped potential in water treatment technologies. In this review, we gather evidence of cellulose nanomaterials' beneficial role in environmental remediation and membranes for water filtration, including their high surface area-to-volume ratio, low environmental impact, high strength, functionalizability, and sustainability. We make direct comparison between cellulose nanomaterials and carbon nanotubes (CNTs) in terms of physical and chemical properties, production costs, use and disposal in order to show the potential of cellulose nanomaterials as a sustainable replacement for CNTs in water treatment technologies. Finally, we comment on the need for improved communication and collaboration across the myriad industries invested in cellulose nanomaterials production and development to achieve an efficient means to commercialization.

  15. Polymorphy in native cellulose: recent developments

    International Nuclear Information System (INIS)

    Atalla, R.H.

    1984-01-01

    In a number of earlier studies, the authors developed a model of cellulose structure based on the existence of two stable, linearly ordered conformations of the cellulose chain that are dominant in celluloses I and II, respectively. The model rests on extensive Raman spectral observations together with conformational considerations and solid-state 13 C-NMR studies. More recently, they have proposed, on the basis of high resolution solid-state 13 C-NMR observations, that native celluloses are composites of two distinct crystalline forms that coexist in different proportions in all native celluloses. In the present work, they examine the Raman spectra of the native celluloses, and reconcile their view of conformational differences with the new level of crystalline polymorphy of native celluloses revealed in the solid-state 13 C-NMR investigations

  16. A novel biochemical route for fuels and chemicals production from cellulosic biomass.

    Directory of Open Access Journals (Sweden)

    Zhiliang Fan

    Full Text Available The conventional biochemical platform featuring enzymatic hydrolysis involves five key steps: pretreatment, cellulase production, enzymatic hydrolysis, fermentation, and product recovery. Sugars are produced as reactive intermediates for subsequent fermentation to fuels and chemicals. Herein, an alternative biochemical route is proposed. Pretreatment, enzymatic hydrolysis and cellulase production is consolidated into one single step, referred to as consolidated aerobic processing, and sugar aldonates are produced as the reactive intermediates for biofuels production by fermentation. In this study, we demonstrate the viability of consolidation of the enzymatic hydrolysis and cellulase production steps in the new route using Neurospora crassa as the model microorganism and the conversion of cellulose to ethanol as the model system. We intended to prove the two hypotheses: 1 cellulose can be directed to produce cellobionate by reducing β-glucosidase production and by enhancing cellobiose dehydrogenase production; and 2 both of the two hydrolysis products of cellobionate--glucose and gluconate--can be used as carbon sources for ethanol and other chemical production. Our results showed that knocking out multiple copies of β-glucosidase genes led to cellobionate production from cellulose, without jeopardizing the cellulose hydrolysis rate. Simulating cellobiose dehydrogenase over-expression by addition of exogenous cellobiose dehydrogenase led to more cellobionate production. Both of the two hydrolysis products of cellobionate: glucose and gluconate can be used by Escherichia coli KO 11 for efficient ethanol production. They were utilized simultaneously in glucose and gluconate co-fermentation. Gluconate was used even faster than glucose. The results support the viability of the two hypotheses that lay the foundation for the proposed new route.

  17. A novel biochemical route for fuels and chemicals production from cellulosic biomass.

    Science.gov (United States)

    Fan, Zhiliang; Wu, Weihua; Hildebrand, Amanda; Kasuga, Takao; Zhang, Ruifu; Xiong, Xiaochao

    2012-01-01

    The conventional biochemical platform featuring enzymatic hydrolysis involves five key steps: pretreatment, cellulase production, enzymatic hydrolysis, fermentation, and product recovery. Sugars are produced as reactive intermediates for subsequent fermentation to fuels and chemicals. Herein, an alternative biochemical route is proposed. Pretreatment, enzymatic hydrolysis and cellulase production is consolidated into one single step, referred to as consolidated aerobic processing, and sugar aldonates are produced as the reactive intermediates for biofuels production by fermentation. In this study, we demonstrate the viability of consolidation of the enzymatic hydrolysis and cellulase production steps in the new route using Neurospora crassa as the model microorganism and the conversion of cellulose to ethanol as the model system. We intended to prove the two hypotheses: 1) cellulose can be directed to produce cellobionate by reducing β-glucosidase production and by enhancing cellobiose dehydrogenase production; and 2) both of the two hydrolysis products of cellobionate--glucose and gluconate--can be used as carbon sources for ethanol and other chemical production. Our results showed that knocking out multiple copies of β-glucosidase genes led to cellobionate production from cellulose, without jeopardizing the cellulose hydrolysis rate. Simulating cellobiose dehydrogenase over-expression by addition of exogenous cellobiose dehydrogenase led to more cellobionate production. Both of the two hydrolysis products of cellobionate: glucose and gluconate can be used by Escherichia coli KO 11 for efficient ethanol production. They were utilized simultaneously in glucose and gluconate co-fermentation. Gluconate was used even faster than glucose. The results support the viability of the two hypotheses that lay the foundation for the proposed new route.

  18. Do Tax Incentives Affect Business Location? Evidence from State Film Incentives

    OpenAIRE

    Patrick Button

    2015-01-01

    I provide the first estimates of the impacts of recently-popular U.S. state film incentives on filming location, establishment location, and employment in the film industry. Filming in this industry is relatively insensitive to locational characteristics, and these incentives are numerous and strong, so this is a good case study to bound the effects of tax incentives on business location. I compile a detailed database of incentives across U.S. states, matching this with TV series and feature ...

  19. fA cellular automaton model of crystalline cellulose hydrolysis by cellulases

    Directory of Open Access Journals (Sweden)

    Little Bryce A

    2011-10-01

    Full Text Available Abstract Background Cellulose from plant biomass is an abundant, renewable material which could be a major feedstock for low emissions transport fuels such as cellulosic ethanol. Cellulase enzymes that break down cellulose into fermentable sugars are composed of different types - cellobiohydrolases I and II, endoglucanase and β-glucosidase - with separate functions. They form a complex interacting network between themselves, soluble hydrolysis product molecules, solution and solid phase substrates and inhibitors. There have been many models proposed for enzymatic saccharification however none have yet employed a cellular automaton approach, which allows important phenomena, such as enzyme crowding on the surface of solid substrates, denaturation and substrate inhibition, to be considered in the model. Results The Cellulase 4D model was developed de novo taking into account the size and composition of the substrate and surface-acting enzymes were ascribed behaviors based on their movements, catalytic activities and rates, affinity for, and potential for crowding of, the cellulose surface, substrates and inhibitors, and denaturation rates. A basic case modeled on literature-derived parameters obtained from Trichoderma reesei cellulases resulted in cellulose hydrolysis curves that closely matched curves obtained from published experimental data. Scenarios were tested in the model, which included variation of enzyme loadings, adsorption strengths of surface acting enzymes and reaction periods, and the effect on saccharide production over time was assessed. The model simulations indicated an optimal enzyme loading of between 0.5 and 2 of the base case concentrations where a balance was obtained between enzyme crowding on the cellulose crystal, and that the affinities of enzymes for the cellulose surface had a large effect on cellulose hydrolysis. In addition, improvements to the cellobiohydrolase I activity period substantially improved overall

  20. Cost estimate for the production of ethanol from spent sulphite liquors and wood residues

    International Nuclear Information System (INIS)

    Nguyen, Q.

    1990-03-01

    A Lotus 1-2-3 spreadsheet model for estimating the production cost of 95 wt % ethanol from spent sulfite liquors (SSL) and from a wood hydrolysis front-end is described. The most economically attractive process is the fermentation of softwood SSL (SSSL) by the yeast Saccharomyces cerevisiae, yielding a production cost estimate of $0.47/liter. The cost of producing ethanol from cellulosic waste (clarifier sludge) via acid hydrolysis is approximately $0.55/liter, still below the market price of ca $0.60/liter for industrial ethanol. Neither the fermentation of hardwood SSL nor the conversion of sawdust to ethanol, using current technology, are economically viable. However, these processes can become commercially viable if acetic acid-tolerant xylose-fermenting yeasts can be found. 17 refs., 12 figs., 16 tabs

  1. Process and technoeconomic analysis of leading pretreatment technologies for lignocellulosic ethanol production using switchgrass.

    Science.gov (United States)

    Tao, Ling; Aden, Andy; Elander, Richard T; Pallapolu, Venkata Ramesh; Lee, Y Y; Garlock, Rebecca J; Balan, Venkatesh; Dale, Bruce E; Kim, Youngmi; Mosier, Nathan S; Ladisch, Michael R; Falls, Matthew; Holtzapple, Mark T; Sierra, Rocio; Shi, Jian; Ebrik, Mirvat A; Redmond, Tim; Yang, Bin; Wyman, Charles E; Hames, Bonnie; Thomas, Steve; Warner, Ryan E

    2011-12-01

    Six biomass pretreatment processes to convert switchgrass to fermentable sugars and ultimately to cellulosic ethanol are compared on a consistent basis in this technoeconomic analysis. The six pretreatment processes are ammonia fiber expansion (AFEX), dilute acid (DA), lime, liquid hot water (LHW), soaking in aqueous ammonia (SAA), and sulfur dioxide-impregnated steam explosion (SO(2)). Each pretreatment process is modeled in the framework of an existing biochemical design model so that systematic variations of process-related changes are consistently captured. The pretreatment area process design and simulation are based on the research data generated within the Biomass Refining Consortium for Applied Fundamentals and Innovation (CAFI) 3 project. Overall ethanol production, total capital investment, and minimum ethanol selling price (MESP) are reported along with selected sensitivity analysis. The results show limited differentiation between the projected economic performances of the pretreatment options, except for processes that exhibit significantly lower monomer sugar and resulting ethanol yields. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. High pressure HC1 conversion of cellulose to glucose

    Energy Technology Data Exchange (ETDEWEB)

    Antonoplis, Robert Alexander [Univ. of California, Berkeley, CA (United States); Blanch, Harvey W. [Univ. of California, Berkeley, CA (United States); Wilke, Charles R. [Univ. of California, Berkeley, CA (United States)

    1981-08-01

    The production of ethanol from glucose by means of fermentation represents a potential long-range alternative to oil for use as a transportation fuel. Today's rising oil prices and the dwindling world supply of oil have made other fuels, such as ethanol, attractive alternatives. It has been shown that automobiles can operate, with minor alterations, on a 10% ethanol-gasoline mixture popularly known as gasohol. Wood has long been known as a potential source of glucose. Glucose may be obtained from wood following acid hydrolysis. In this research, it was found that saturating wood particles with HCl gas under pressure was an effective pretreatment before subjecting the wood to dilute acid hydrolysis. The pretreatment is necessary because of the tight lattice structure of cellulose, which inhibits dilute acid hydrolysis. HCl gas makes the cellulose more susceptible to hydrolysis and the glucose yield is doubled when dilute acid hydrolysis is preceded by HCl saturation at high pressure. The saturation was most effectively performed in a fluidized bed reactor, with pure HCl gas fluidizing equal volumes of ground wood and inert particles. The fluidized bed effectively dissipated the large amount of heat released upon HCl absorption into the wood. Batch reaction times of one hour at 314.7 p.s.i.a. gave glucose yields of 80% and xylose yields of 95% after dilute acid hydrolysis. A non-catalytic gas-solid reaction model, with gas diffusing through the solid limiting the reaction rate, was found to describe the HCl-wood reaction in the fluidized bed. HCl was found to form a stable adduct with the lignin residue in the wood, in a ratio of 3.33 moles per mole of lignin monomer. This resulted in a loss of 0.1453 lb. of HCl per pound of wood. The adduct was broken upon the addition of water. A process design and economic evaluation for a plant to produce 214 tons per day of glucose from air-dried ground Populus tristi gave an estimated glucose cost of 15.14 cents per pound

  3. Isolation and structural characterization of sugarcane bagasse lignin after dilute phosphoric acid plus steam explosion pretreatment and its effect on cellulose hydrolysis

    Science.gov (United States)

    Jijiao Zeng; Zhaohui Tong; Letian Wang; J.Y. Zhu; Lonnie Ingram

    2014-01-01

    The structure of lignin after dilute phosphoric acid plus steam explosion pretreatment process of sugarcane bagasse in a pilot scale and the effect of the lignin extracted by ethanol on subsequent cellulose hydrolysis were investigated. The lignin structural changes caused by pretreatment were identified using advanced nondestructive techniques such as gel permeation...

  4. Wet oxidation pretreatment of rape straw for ethanol production

    DEFF Research Database (Denmark)

    Arvaniti, Efthalia; Bjerre, Anne Belinda; Schmidt, Jens Ejbye

    2012-01-01

    Rape straw can be used for production of second generation bioethanol. In this paper we optimized the pretreatment of rape straw for this purpose using Wet oxidation (WO). The effect of reaction temperature, reaction time, and oxygen gas pressure was investigated for maximum ethanol yield via...... Simultaneous Saccharification and Fermentation (SSF). To reduce the water use and increase the energy efficiency in WO pretreatment features like recycling liquid (filtrate), presoaking of rape straw in water or recycled filtrate before WO, skip washing pretreated solids (filter cake) after WO, or use of whole...... gas produced higher ethanol yields and cellulose, hemicelluloses, and lignin recoveries, than 15 min WO treatment at 195 °C. Also, recycling filtrate and use of higher oxygen gas pressure reduced recovery of materials. The use of filtrate could be inhibitory for the yeast, but also reduced lactic acid...

  5. Ethanol fuels in Brazil

    International Nuclear Information System (INIS)

    Trindade, S.C.

    1993-01-01

    The largest alternative transportation fuels program in the world today is Brazil's Proalcool Program. About 6.0 million metric tons of oil equivalent (MTOE) of ethanol, derived mainly from sugar cane, were consumed as transportation fuels in 1991 (equivalent to 127,000 barrels of crude oil per day). Total primary energy consumed by the Brazilian economy in 1991 was 184.1 million MTOE, and approximately 4.3 million vehicles -- about one third of the total vehicle fleet or about 40 percent of the total car population -- run on hydrous or open-quotes neatclose quotes ethanol at the azeotropic composition (96 percent ethanol, 4 percent water, by volume). Additional transportation fuels available in the country are diesel and gasoline, the latter of which is defined by three grades. Gasoline A (regular, leaded gas)d has virtually been replaced by gasoline C, a blend of gasoline and up to 22 percent anhydrous ethanol by volume, and gasoline B (premium gasoline) has been discontinued as a result of neat ethanol market penetration

  6. Cellulose Triacetate Synthesis from Cellulosic Wastes by Heterogeneous Reactions

    Directory of Open Access Journals (Sweden)

    Sherif Shawki Z. Hindi

    2015-06-01

    Full Text Available Cellulosic fibers from cotton fibers (CF, recycled writing papers (RWP, recycled newspapers (RN, and macerated woody fibers of Leucaena leucocephala (MWFL were acetylated by heterogeneous reactions with glacial acetic acid, concentrated H2SO4, and acetic anhydride. The resultant cellulose triacetate (CTA was characterized for yield and solubility as well as by using 1H-NMR spectroscopy and SEM. The acetylated product (AP yields for CF, RWP, RN, and MWFL were 112, 94, 84, and 73%, respectively. After isolation of pure CTA from the AP, the CTA yields were 87, 80, 68, and 54%. The solubility test for the CTA’s showed a clear solubility in chloroform, as well as mixture of chloroform and methanol (9:1v/v and vice versa for acetone. The degree of substitution (DS values for the CTA’s produced were nearly identical and confirmed the presence of CTA. In addition, the pore diameter of the CTA skeleton ranged from 0.072 to 0.239 µm for RWP and RN, and within the dimension scale of the CTA pinholes confirm the synthesis of CTA. Accordingly, pouring of the AP liquor at 25 °C in distilled water at the end of the acetylation and filtration did not hydrolyze the CTA to cellulose diacetate.

  7. Utilization of household food waste for the production of ethanol at high dry material content.

    Science.gov (United States)

    Matsakas, Leonidas; Kekos, Dimitris; Loizidou, Maria; Christakopoulos, Paul

    2014-01-08

    Environmental issues and shortage of fossil fuels have turned the public interest to the utilization of renewable, environmentally friendly fuels, such as ethanol. In order to minimize the competition between fuels and food production, researchers are focusing their efforts to the utilization of wastes and by-products as raw materials for the production of ethanol. household food wastes are being produced in great quantities in European Union and their handling can be a challenge. Moreover, their disposal can cause severe environmental issues (for example emission of greenhouse gasses). On the other hand, they contain significant amounts of sugars (both soluble and insoluble) and they can be used as raw material for the production of ethanol. Household food wastes were utilized as raw material for the production of ethanol at high dry material consistencies. A distinct liquefaction/saccharification step has been included to the process, which rapidly reduced the viscosity of the high solid content substrate, resulting in better mixing of the fermenting microorganism. This step had a positive effect in both ethanol production and productivity, leading to a significant increase in both values, which was up to 40.81% and 4.46 fold, respectively. Remaining solids (residue) after fermentation at 45% w/v dry material (which contained also the unhydrolyzed fraction of cellulose), were subjected to a hydrothermal pretreatment in order to be utilized as raw material for a subsequent ethanol fermentation. This led to an increase of 13.16% in the ethanol production levels achieving a final ethanol yield of 107.58 g/kg dry material. In conclusion, the ability of utilizing household food waste for the production of ethanol at elevated dry material content has been demonstrated. A separate liquefaction/saccharification process can increase both ethanol production and productivity. Finally, subsequent fermentation of the remaining solids could lead to an increase of the overall

  8. Environmental aspects of ethanol-based fuels from Brassica carinata. A case study of second generation ethanol

    International Nuclear Information System (INIS)

    Gonzalez-Garcia, Sara; Moreira, M'a Teresa; Feijoo, Gumersindo; Gasol, Carles M.; Gabarrell, Xavier; Rieradevall, Joan

    2009-01-01

    One of the main challenges faced by mankind in the 21st century is to meet the increasing demand for energy requirements by means of a more sustainable energy supply. In countries that are net fossil fuel importers, expectation about the benefit of using alternative fuels on reducing oil imports is the primary driving force behind efforts to promote its production and use. Spain is scarce in domestic energy sources and more than 50% of the energy used is fossil fuel based. The promotion of renewable energies use is one of the principal vectors in the Spanish energy policy. Selected herbaceous crops such as Brassica carinata are currently under study as potential energy sources. Its biomass can be considered as potential feedstock to ethanol conversion by an enzymatic process due to the characteristics of its composition, rich in cellulose and hemicellulose. This paper aims to analyse the environmental performance of two ethanol-based fuel applications (E10 and E85) in a passenger car (E10 fuel: a mixture of 10% ethanol and 90% gasoline by volume; E85 fuel: a mixture of 85% ethanol and 15% gasoline by volume) as well as their comparison with conventional gasoline as transport fuel. Two types of functional units are applied in this study: ethanol production oriented and travelling distance oriented functional units in order to reflect the availability or not of ethanol supply. E85 seems to be the best alternative when ethanol production based functional unit is considered in terms of greenhouse gas (GHG) emissions and E10 in terms of non-renewable energy resources use. Nevertheless, E85 offers the best environmental performance when travelling distance oriented functional unit is assumed in both impacts. In both functional unit perspectives, the use of ethanol-based fuels reduces the global warming and fossil fuels consumption. However, the contributions to other impact indicators (e.g. acidification, eutrophication and photochemical oxidants formation) were lower

  9. 7 CFR 3560.656 - Incentives offers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Incentives offers. 3560.656 Section 3560.656... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Housing Preservation § 3560.656 Incentives offers. (a) The Agency will offer a borrower, who submits a prepayment request meeting the conditions of § 3560...

  10. Changes in Incentives, Rewards and Sanctions.

    Science.gov (United States)

    Lonsdale, Alan

    1993-01-01

    A review of the literature over the past decade reflects substantial changes in rewards, incentives, and sanctions used with college faculty. These changes parallel changes in the public sector generally. Increasing emphasis on formal evaluation and on use of money as an incentive and reward for performance is noted. (MSE)

  11. Behavioural economics: Cash incentives avert deforestation

    Science.gov (United States)

    Cárdenas, Juan Camilo

    2017-10-01

    There is tension in developing countries between financial incentives to clear forests and climate regulation benefits of preserving trees. Now research shows that paying private forest owners in Uganda reduced deforestation, adding to the debate on the use of monetary incentives in forest conservation.

  12. Incentive theory: IV. Magnitude of reward

    OpenAIRE

    Killeen, Peter R.

    1985-01-01

    Incentive theory is successfully applied to data from experiments in which the amount of food reward is varied. This is accomplished by assuming that incentive value is a negatively accelerated function of reward duration. The interaction of the magnitude of a reward with its delay is confirmed, and the causes and implications of this interaction are discussed.

  13. Incentive contracts for development projects

    Science.gov (United States)

    Finley, David T.; Smith, Byron; DeGroff, B.

    2012-09-01

    Finding a contract vehicle that balances the concerns of the customer and the contractor in a development project can be difficult. The customer wants a low price and an early delivery, with as few surprises as possible as the project progresses. The contractor wants sufficient cost and schedule to cover risk. Both want to clearly define what each party will provide. Many program offices do not want to award cost plus contracts because their funding sources will not allow it, their boards do not want an open ended commitment, and they feel like they lose financial control of the project. A fixed price incentive contract, with a mutually agreed upon target cost, provides the owner with visibility into the project and input into the execution of the project, encourages both parties to save costs, and stimulates a collaborative atmosphere by aligning the respective interests of customers and contractors.

  14. Application of Box-Behnken Design in Optimization of Glucose Production from Oil Palm Empty Fruit Bunch Cellulose

    Directory of Open Access Journals (Sweden)

    Satriani Aga Pasma

    2013-01-01

    Full Text Available Oil palm empty fruit bunch fiber (OPEFB is a lignocellulosic waste from palm oil mills. It contains mainly cellulose from which glucose can be derived to serve as raw materials for valuable chemicals such as succinic acid. A three-level Box-Behnken design combined with the canonical and ridge analysis was employed to optimize the process parameters for glucose production from OPEFB cellulose using enzymatic hydrolysis. Organosolv pretreatment was used to extract cellulose from OPEFB using ethanol and water as the solvents. The extracted cellulose was characterized by thermogravimetric analysis, FTIR spectroscopy, and field emission scanning electron microscopy. Hydrolysis parameters including amount of enzyme, amount of cellulose, and reaction time were investigated. The experimental results were fitted with a second-order polynomial equation by a multiple regression analysis and found that more than 97% of the variations could be predicted by the models. Using the ridge analysis, the optimal conditions reaction time found for the production of glucose was 76 hours and 30 min, whereas the optimum amount of enzyme and cellulose was 0.5 mL and 0.9 g, respectively. Under these optimal conditions, the corresponding response value predicted for glucose concentration was 169.34 g/L, which was confirmed by validation experiments.

  15. Converting Eucalyptus biomass into ethanol: Financial and sensitivity analysis in a co-current dilute acid process. Part II

    International Nuclear Information System (INIS)

    Gonzalez, R.; Treasure, T.; Phillips, R.; Jameel, H.; Saloni, D.; Wright, J.; Abt, R.

    2011-01-01

    The technical and financial performance of high yield Eucalyptus biomass in a co-current dilute acid pretreatment followed by enzymatic hydrolysis process was simulated using WinGEMS registered and Excel registered . Average ethanol yield per dry Mg of Eucalyptus biomass was approximately 347.6 L of ethanol (with average carbohydrate content in the biomass around 66.1%) at a cost of 0.49 L -1 of ethanol, cash cost of ∝0.46 L -1 and CAPEX of 1.03 L -1 of ethanol. The main cost drivers are: biomass, enzyme, tax, fuel (gasoline), depreciation and labor. Profitability of the process is very sensitive to biomass cost, carbohydrate content (%) in biomass and enzyme cost. Biomass delivered cost was simulated and financially evaluated in Part I; here in Part II the conversion of this raw material into cellulosic ethanol using the dilute acid process is evaluated. (author)

  16. Customer response on price incentives

    International Nuclear Information System (INIS)

    Naesje, Paal C.; Andersen, Thale K.; Saele, Hanne

    2005-01-01

    This paper analyses the relation between end-users energy attitudes and their corresponding energy behaviour. It presents empirical findings from analyses of the effects of two-way communication between consumers and power companies. Two-way communication has made available high quality data on energy consumption. In the build-up to the analysis in this paper the a number of aspects thought to influence energy consumption has been looked at; including standard of housing, number and age of residents, as well as socio-economic factors, behaviour and preferences. Here we choose to focus specifically on attitudes and behaviour. These aspects are controlled for price incentives. The combination of very tight peak power balance in the Nordic power system and few investments in extension of power networks has turned the focus towards manual or automatic demand-response which requires hourly metering for documentation. The data are two-fold: Hourly recordings of meter-data of electric consumption of 10,894 customers (nearly half of these had installed technology for remote load control) in two different network areas and survey-data from a questionnaire distributed to consumers that resulted in nearly 550 answers. During the winter 2003/2004 these customers were offered different price incentives. The analyses showed a net reduction in electricity consumption of 1,0 kWh/h at the most in peak load hours. The paper is based on two connected studies, 'End-user flexibility by efficient use of ICT' and 'Improving end-user knowledge for managing energy loads end consumption' conducted in Norway by the SINTEF group

  17. Co-production of bio-ethanol, electricity and heat from biomass residues

    Energy Technology Data Exchange (ETDEWEB)

    Reith, J.H.; Den Uil, H.; Van Veen, H. [ECN Biomass, Petten (Netherlands); De Laat, W.T.A.M.; Niessen, J.J. [Royal Nedalco, Bergen op Zoom (Netherlands); De Jong, E.; Elbersen, H.W.; Weusthuis, R. [Agrotechnological Research Institute ATO, BU Renewable Resources, Wageningen (Netherlands); Van Dijken, J.P.; Raamsdonk, L. [Delft University of Technology, Delft (Netherlands)

    2002-07-01

    The use of lignocellulose biomass residues as a feedstock offers good perspectives for large scale production of fuel ethanol at competitive costs. An evaluation was performed to assess the international status of lignocellulose-to-bioethanol technology and the economical and ecological system performance, to identify RandD approaches for further development. Deriving fermentable sugars from the hemicellulose and cellulose fractions of lignocellulose materials via suitable pretreatment and enzymatic cellulose hydrolysis is a critical RandD issue. Further development of pretreatment via mild, low temperature alkaline extraction or weak acid hydrolysis using CO2, dissolved in pressurized hot water ('carbonic acid process') shows good perspectives. Enzymatic cellulose hydrolysis with the currently available industrial cellulases accounts for 36-45% of ethanol production costs. At least a 10-fold increase of cellulase cost-effectiveness is required. Despite substantial RandD efforts, no suitable fermentation system is currently available for the fermentation of pentoses (mainly xylose) from the hemicellulose fraction. Several strains of anaerobic, thermophilic bacteria are able to convert all (hemi)cellulose components into ethanol. Follow-up RandD will focus on isolation of suitable strain(s) from this group. The system evaluation shows a 40-55% energetic efficiency (LHV basis) for conversion of lignocellulose feedstocks to ethanol. Thermal conversion of non-fermentable residues (mainly lignin) in a Biomass-Integrated-Gasifier/Combined Cycle (BIG/CC) system can provide the total steam and electricity requirement for the production process and an electricity surplus for export to the grid, giving a total system efficiency of 56-68%. Water consumption in the process (28-54 liter water/liter ethanol) is much higher than in current ethanol production (lo-15 l/l ethanol). The large amount of process water (used in the pretreatment and cellulose hydrolysis

  18. Wet oxidation treatment of organic household waste enriched with wheat straw for simultaneous saccharification and fermentation into ethanol

    DEFF Research Database (Denmark)

    Lissens, G.; Klinke, H.B.; Verstraete, W.

    2004-01-01

    Organic municipal solid waste enriched with wheat straw was subjected to wet-oxidation as a pre-treatment for subsequent enzymatic conversion and fermentation into bio-ethanol. The effect of tempera (185-195degrees C), oxygen pressure (3-12) and sodium carbonate (0-2 g l(-1)) addition on enzymatic...... in the treated waste could be converted into respectively hexose and pentose sugars compared to 46% for cellulose and 36% for hemicellulose in the raw waste. For all wet oxidation conditions tested, total carbohydrate recoveries were high (> 89%) and 44-66% of the original lignin could be converted into non......-toxic carboxylic acids mainly (2.2-4.5 % on DS basis). Simultaneous saccharification and fermentation (SSF) of the treated waste at 10% DS by Saccharomyces cerevisae yielded average ethanol concentrations of 16.5 to 22 g l(-1) for enzyme loadings of 5 and 25 FPU g(-1) DS, respectively. The cellulose to ethanol...

  19. Improved ethanol production at high temperature by consolidated bioprocessing using Saccharomyces cerevisiae strain engineered with artificial zinc finger protein.

    Science.gov (United States)

    Khatun, M Mahfuza; Yu, Xinshui; Kondo, Akihiko; Bai, Fengwu; Zhao, Xinqing

    2017-12-01

    In this work, the consolidated bioprocessing (CBP) yeast Saccharomyces cerevisiae MNII/cocδBEC3 was transformed by an artificial zinc finger protein (AZFP) library to improve its thermal tolerance, and the strain MNII-AZFP with superior growth at 42°C was selected. Improved degradation of acid swollen cellulose by 45.9% led to an increase in ethanol production, when compared to the control strain. Moreover, the fermentation of Jerusalem artichoke stalk (JAS) by MNII-AZFP was shortened by 12h at 42°C with a concomitant improvement in ethanol production. Comparative transcriptomics analysis suggested that the AZFP in the mutant exerted beneficial effect by modulating the expression of multiple functional genes. These results provide a feasible strategy for efficient ethanol production from JAS and other cellulosic biomass through CBP based-fermentation at elevated temperatures. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. CELLULOSE DEGRADATION BY OXIDATIVE ENZYMES

    Directory of Open Access Journals (Sweden)

    Maria Dimarogona

    2012-09-01

    Full Text Available Enzymatic degradation of plant biomass has attracted intensive research interest for the production of economically viable biofuels. Here we present an overview of the recent findings on biocatalysts implicated in the oxidative cleavage of cellulose, including polysaccharide monooxygenases (PMOs or LPMOs which stands for lytic PMOs, cellobiose dehydrogenases (CDHs and members of carbohydrate-binding module family 33 (CBM33. PMOs, a novel class of enzymes previously termed GH61s, boost the efficiency of common cellulases resulting in increased hydrolysis yields while lowering the protein loading needed. They act on the crystalline part of cellulose by generating oxidized and non-oxidized chain ends. An external electron donor is required for boosting the activity of PMOs. We discuss recent findings concerning their mechanism of action and identify issues and questions to be addressed in the future.

  1. Glycerine Treated Nanofibrillated Cellulose Composites

    Directory of Open Access Journals (Sweden)

    Esra Erbas Kiziltas

    2016-01-01

    Full Text Available Glycerine treated nanofibrillated cellulose (GNFC was prepared by mixing aqueous nanofibrillated cellulose (NFC suspensions with glycerine. Styrene maleic anhydride (SMA copolymer composites with different loadings of GNFC were prepared by melt compounding followed by injection molding. The incorporation of GNFC increased tensile and flexural modulus of elasticity of the composites. Thermogravimetric analysis showed that as GNFC loading increased, the thermal stability of the composites decreased marginally. The incorporation of GNFC into the SMA copolymer matrix resulted in higher elastic modulus (G′ and shear viscosities than the neat SMA copolymer, especially at low frequencies. The orientation of rigid GNFC particles in the composites induced a strong shear thinning behavior with an increase in GNFC loading. The decrease in the slope of elastic modulus with increasing GNFC loading suggested that the microstructural changes of the polymer matrix can be attributed to the incorporation of GNFC. Scanning electron microscopy (SEM images of fracture surfaces show areas of GNFC agglomerates in the SMA matrix.

  2. Polyimide Cellulose Nanocrystal Composite Aerogels

    Science.gov (United States)

    Nguyen, Baochau N.; Meador, Mary Ann; Rowan, Stuart; Cudjoe, Elvis; Sandberg, Anna

    2014-01-01

    Polyimide (PI) aerogels are highly porous solids having low density, high porosity and low thermal conductivity with good mechanical properties. They are ideal for various applications including use in antenna and insulation such as inflatable decelerators used in entry, decent and landing operations. Recently, attention has been focused on stimuli responsive materials such as cellulose nano crystals (CNCs). CNCs are environmentally friendly, bio-renewable, commonly found in plants and the dermis of sea tunicates, and potentially low cost. This study is to examine the effects of CNC on the polyimide aerogels. The CNC used in this project are extracted from mantle of a sea creature called tunicates. A series of polyimide cellulose nanocrystal composite aerogels has been fabricated having 0-13 wt of CNC. Results will be discussed.

  3. Water consumption in the production of ethanol and petroleum gasoline.

    Science.gov (United States)

    Wu, May; Mintz, Marianne; Wang, Michael; Arora, Salil

    2009-11-01

    We assessed current water consumption during liquid fuel production, evaluating major steps of fuel lifecycle for five fuel pathways: bioethanol from corn, bioethanol from cellulosic feedstocks, gasoline from U.S. conventional crude obtained from onshore wells, gasoline from Saudi Arabian crude, and gasoline from Canadian oil sands. Our analysis revealed that the amount of irrigation water used to grow biofuel feedstocks varies significantly from one region to another and that water consumption for biofuel production varies with processing technology. In oil exploration and production, water consumption depends on the source and location of crude, the recovery technology, and the amount of produced water re-injected for oil recovery. Our results also indicate that crop irrigation is the most important factor determining water consumption in the production of corn ethanol. Nearly 70% of U.S. corn used for ethanol is produced in regions where 10-17 liters of water are consumed to produce one liter of ethanol. Ethanol production plants are less water intensive and there is a downward trend in water consumption. Water requirements for switchgrass ethanol production vary from 1.9 to 9.8 liters for each liter of ethanol produced. We found that water is consumed at a rate of 2.8-6.6 liters for each liter of gasoline produced for more than 90% of crude oil obtained from conventional onshore sources in the U.S. and more than half of crude oil imported from Saudi Arabia. For more than 55% of crude oil from Canadian oil sands, about 5.2 liters of water are consumed for each liter of gasoline produced. Our analysis highlighted the vital importance of water management during the feedstock production and conversion stage of the fuel lifecycle.

  4. Water Consumption in the Production of Ethanol and Petroleum Gasoline

    Science.gov (United States)

    Wu, May; Mintz, Marianne; Wang, Michael; Arora, Salil

    2009-11-01

    We assessed current water consumption during liquid fuel production, evaluating major steps of fuel lifecycle for five fuel pathways: bioethanol from corn, bioethanol from cellulosic feedstocks, gasoline from U.S. conventional crude obtained from onshore wells, gasoline from Saudi Arabian crude, and gasoline from Canadian oil sands. Our analysis revealed that the amount of irrigation water used to grow biofuel feedstocks varies significantly from one region to another and that water consumption for biofuel production varies with processing technology. In oil exploration and production, water consumption depends on the source and location of crude, the recovery technology, and the amount of produced water re-injected for oil recovery. Our results also indicate that crop irrigation is the most important factor determining water consumption in the production of corn ethanol. Nearly 70% of U.S. corn used for ethanol is produced in regions where 10-17 liters of water are consumed to produce one liter of ethanol. Ethanol production plants are less water intensive and there is a downward trend in water consumption. Water requirements for switchgrass ethanol production vary from 1.9 to 9.8 liters for each liter of ethanol produced. We found that water is consumed at a rate of 2.8-6.6 liters for each liter of gasoline produced for more than 90% of crude oil obtained from conventional onshore sources in the U.S. and more than half of crude oil imported from Saudi Arabia. For more than 55% of crude oil from Canadian oil sands, about 5.2 liters of water are consumed for each liter of gasoline produced. Our analysis highlighted the vital importance of water management during the feedstock production and conversion stage of the fuel lifecycle.

  5. Investigation of Pleurotus ostreatus pretreatment on switchgrass for ethanol production

    Science.gov (United States)

    Slavens, Shelyn Gehle

    Fungal pretreatment using the white-rot fungus Pleurotus ostreatus on switchgrass for ethanol production was studied. In a small-scale storage study, small switchgrass bales were inoculated with fungal spawn and automatically watered to maintain moisture. Sampled at 25, 53, and 81 d, the switchgrass composition was determined and liquid hot water (LHW) pretreatment was conducted. Fungal pretreatment significantly decreased the xylan and lignin content; glucan was not significantly affected by fungal loading. The glucan, xylan, and lignin contents significantly decreased with increased fungal pretreatment time. The effects of the fungal pretreatment were not highly evident after the LHW pretreatment, showing only changes based on sampling time. Although other biological activity within the bales increased cellulose degradation, the fungal pretreatment successfully reduced the switchgrass lignin and hemicellulose contents. In a laboratory-scale nutrient supplementation study, copper, manganese, glucose, or water was added to switchgrass to induce production of ligninolytic enzymes by P. ostreatus. After 40 d, ligninolytic enzyme activities and biomass composition were determined and simultaneous saccharification and fermentation (SSF) was conducted to determine ethanol yield. Laccase activity was similar for all supplements and manganese peroxidase (MnP) activity was significantly less in copper-treated samples than in the other fungal-inoculated samples. The fungal pretreatment reduced glucan, xylan, and lignin content, while increasing extractable sugars content. The lowest lignin contents occurred in the water-fungal treated samples and produced the greatest ethanol yields. The greatest lignin contents occurred in the copper-fungal treated samples and produced the lowest ethanol yields. Manganese-fungal and glucose-fungal treated samples had similar, intermediate lignin contents and produced similar, intermediate ethanol yields. Ethanol yields from switchgrass

  6. Immobilization of Saccharomyces Cerevisiae in Rice Hulls for Ethanol Production

    Directory of Open Access Journals (Sweden)

    Edita Martini

    2011-05-01

    Full Text Available The whole cell immobilization in ethanol fermentation can be done by using natural carriers or through synthetic carriers. All of these methods have the same purpose of retaining high cell concentrations within a certain defined region of space which leads to higher ethanol productivity. Lignocellulosic plant substance represents one of highly potential sources in ethanol production. Some studies have found that cellulosic substances substances can also be used as a natural carrier in cell immobilization by re-circulating pre-culture medium into a reactor. In this experiment, rice hulls without any treatment were used to immobilize Saccharomyces cerevisiae through semi solid state incubation combined with re-circulating pre-culture medium. The scanning electron microscopy (SEM pictures of the carrier show that the yeast cells are absorbed and embedded to the rice hull pore. In liquid batch fermentation system with an initial sugar concentration of 50 g/L, nearly 100% total sugar was consumed after 48 hours. This resulted in an ethanol yield of 0.32 g ethanol/g glucose, which is 62.7% of the theoretical value. Ethanol productivity of 0.59 g/(L.h is 2.3 fold higher than that of free cells which is 0.26 g/(L.h. An effort to reuse the immobilized cells in liquid fermentation system showed poor results due to cell desorption in the first batch which led to high sugar concentration inhibitory effect in the second batch fermentation. This might be solved by using semi solid fermentation process in the future work.

  7. The Impact of Lottery Incentives on Student Survey Response Rates.

    Science.gov (United States)

    Porter, Stephen R.; Whitcomb, Michael E.

    2003-01-01

    A controlled experiment tested the effects of lottery incentives using a prospective college applicant Web survey, with emails sent to more than 9,000 high school students. Found minimal effect of postpaid incentives for increasing levels of incentive. (EV)

  8. Process Intensification for Cellulosic Biorefineries.

    Science.gov (United States)

    Sadula, Sunitha; Athaley, Abhay; Zheng, Weiqing; Ierapetritou, Marianthi; Saha, Basudeb

    2017-06-22

    Utilization of renewable carbon source, especially non-food biomass is critical to address the climate change and future energy challenge. Current chemical and enzymatic processes for producing cellulosic sugars are multistep, and energy- and water-intensive. Techno-economic analysis (TEA) suggests that upstream lignocellulose processing is a major hurdle to the economic viability of the cellulosic biorefineries. Process intensification, which integrates processes and uses less water and energy, has the potential to overcome the aforementioned challenges. Here, we demonstrate a one-pot depolymerization and saccharification process of woody biomass, energy crops, and agricultural residues to produce soluble sugars with high yields. Lignin is separated as a solid for selective upgrading. Further integration of our upstream process with a reactive extraction step makes energy-efficient separation of sugars in the form of furans. TEA reveals that the process efficiency and integration enable, for the first time, economic production of feed streams that could profoundly improve process economics for downstream cellulosic bioproducts. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Utilization of agricultural cellulose wastes

    Energy Technology Data Exchange (ETDEWEB)

    Valkanas, G N; Economidis, D G; Koukios, E G; Valkanas, C G

    1977-05-05

    Wastes, example, straw, are prehydrolyzed to convert pentosanes, starches, and hemicelluloses to monosaccharides; the remaining pulp is 50% cellulose. Thus, dry wheat straw 0.8 kg was treated with 10 L of 0.3% aqueous HCl at 5-5.5 atm and 145/sup 0/ and a space velocity of 0.55 L/min, washed with dry steam, followed by water at 120 to 130/sup 0/, and more dry steam, and compressed at 25 kg/cm/sup 2/ to yield a product containing 45 to 50 wt % water. The sugar solution obtained (1394 L) contained 1.34 wt % reducing sugars, a straw hydrolysis of 23 wt %, and comprised xylose 74.3, mannose 5.2, arabinose 11.8, glucose 5.9, galactose 2.9%, and furfural 0.16 g/L. The cellulose residue had a dry weight of 0.545 kg. a yield of 68.2 wt % and contained cellulose 53.1, hemicelluloses 12.6%, lignin 22.1, ash and extractables 12.2%. The degree of polymerization was 805 glucose units.

  10. Xylose isomerase improves growth and ethanol production rates from biomass sugars for both Saccharomyces pastorianus and Saccharomyces cerevisiae.

    Science.gov (United States)

    Miller, Kristen P; Gowtham, Yogender Kumar; Henson, J Michael; Harcum, Sarah W

    2012-01-01

    The demand for biofuel ethanol made from clean, renewable nonfood sources is growing. Cellulosic biomass, such as switch grass (Panicum virgatum L.), is an alternative feedstock for ethanol production; however, cellulosic feedstock hydrolysates contain high levels of xylose, which needs to be converted to ethanol to meet economic feasibility. In this study, the effects of xylose isomerase on cell growth and ethanol production from biomass sugars representative of switch grass were investigated using low cell density cultures. The lager yeast species Saccharomyces pastorianus was grown with immobilized xylose isomerase in the fermentation step to determine the impact of the glucose and xylose concentrations on the ethanol production rates. Ethanol production rates were improved due to xylose isomerase; however, the positive effect was not due solely to the conversion of xylose to xylulose. Xylose isomerase also has glucose isomerase activity, so to better understand the impact of the xylose isomerase on S. pastorianus, growth and ethanol production were examined in cultures provided fructose as the sole carbon. It was observed that growth and ethanol production rates were higher for the fructose cultures with xylose isomerase even in the absence of xylose. To determine whether the positive effects of xylose isomerase extended to other yeast species, a side-by-side comparison of S. pastorianus and Saccharomyces cerevisiae was conducted. These comparisons demonstrated that the xylose isomerase increased ethanol productivity for both the yeast species by increasing the glucose consumption rate. These results suggest that xylose isomerase can contribute to improved ethanol productivity, even without significant xylose conversion. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  11. Comparison of Different Pretreatment Strategies for Ethanol Production of West African Biomass

    DEFF Research Database (Denmark)

    Thomsen, Sune Tjalfe; Gonzalez Londono, Jorge Enrique; Schmidt, Jens Ejbye

    2015-01-01

    husks, cocoa pods, maize cobs, maize stalks, rice straw, groundnut straw and oil palm empty fruit bunches. It was found that four biomass’ (plantain peelings, plantain trunks, maize cobs and maize stalks) were most promising for production of cellulosic ethanol with profitable enzymatic conversion......Pretreating lignocellulosic biomass for cellulosic ethanol production in a West African setting requires smaller scale and less capital expenditure compared to current state of the art. In the present study, three low-tech methods applicable for West African conditions, namely Boiling Pretreatment...... (BP), Soaking in Aqueous Ammonia (SAA) and White Rot Fungi pretreatment (WRF), were compared to the high-tech solution of hydrothermal pretreatment (HTT). The pretreatment methods were tested on 11 West African biomasses, i.e. cassava stalks, plantain peelings, plantain trunks, plantain leaves, cocoa...

  12. Biochemistry of cellulose degradation and cellulose utilization for feeds and for protein

    Energy Technology Data Exchange (ETDEWEB)

    Sadara, J C; Lachke, A H; Shewale, J G

    1979-01-01

    A review discussing production of single-cell protein, fuel, and glucose from cellulose decomposition; surface or solid fermentations of single-cell protein; production of cellulases; and the biochemistry of cellulose degradation was presented.

  13. Cellulose-binding domains: tools for innovation in cellulosic fibre production and modification

    NARCIS (Netherlands)

    Quentin, M.G.E.; Valk, van der H.C.P.M.; Dam, van J.E.G.; Jong, de E.

    2003-01-01

    Plant cell walls are composed of cellulose, nature's most abundant macromolecule, and therefore represent a renewable resource of special technical importance. Cellulose degrading enzymes involved in plant cell wall loosening (expansins), or produced by plant pathogenic microorganisms (cellulases),

  14. High Dehumidification Performance of Amorphous Cellulose Composite Membranes prepared from Trimethylsilyl Cellulose

    KAUST Repository

    Puspasari, Tiara; Akhtar, Faheem Hassan; Ogieglo, Wojciech; Alharbi, Ohoud; Peinemann, Klaus-Viktor

    2018-01-01

    Cellulose is widely regarded as an environmentally friendly, natural and low cost material which can significantly contribute the sustainable economic growth. In this study, cellulose composite membranes were prepared via regeneration

  15. The BEST project - BioEthanol for the Sustainable Transportation - a contribution to the environment of the metropolis; O projeto BEST - BioEtanol para o Transporte Sustentavel - uma contribuicao ao meio ambiente das metropoles

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Velazquez, Silvia Maria Stortini; Santos, Sandra Maria Apolinario; Moreira, Jose Roberto; Melo, Euler Hoffmann; Coelho, Suani Teixeira [Centro Nacional de Referencia em Biomassa (CENBIO), Sao Paulo, SP (Brazil)], E-mail: silvia@iee.usp.br

    2010-07-01

    The BEST Project - Bio Ethanol for the Sustainable Transportation was an initiative of the European Union, coordinated by the Stockholm City Hall, at Sweden. This project gave incentives the use of ethanol, replacing the Diesel fuel, at the public transportation in Brazil and in the world. The used vehicles in the tests were monitored and evaluated to demonstrate the efficiency and environmental energy of the ethanol, and after the results, the BEST project and the European Union gave recommendations for the formulation of public politics of incentives to the use of technology.

  16. Implications of increased ethanol production

    International Nuclear Information System (INIS)

    1992-06-01

    The implications of increased ethanol production in Canada, assuming a 10% market penetration of a 10% ethanol/gasoline blend, are evaluated. Issues considered in the analysis include the provision of new markets for agricultural products, environmental sustainability, energy security, contribution to global warming, potential government cost (subsidies), alternative options to ethanol, energy efficiency, impacts on soil and water of ethanol crop production, and acceptance by fuel marketers. An economic analysis confirms that ethanol production from a stand-alone plant is not economic at current energy values. However, integration of ethanol production with a feedlot lowers the break-even price of ethanol by about 35 cents/l, and even further reductions could be achieved as technology to utilize lignocellulosic feedstock is commercialized. Ethanol production could have a positive impact on farm income, increasing cash receipts to grain farmers up to $53 million. The environmental impact of ethanol production from grain would be similar to that from crop production in general. Some concerns about ethanol/gasoline blends from the fuel industry have been reduced as those blends are now becoming recommended in some automotive warranties. However, the concerns of the larger fuel distributors are a serious constraint on an expansion of ethanol use. The economics of ethanol use could be improved by extending the federal excise tax exemption now available for pure alcohol fuels to the alcohol portion of alcohol/gasoline blends. 9 refs., 10 tabs

  17. Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, September 1-November 30, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wang, D.I.; Cooney, C.L.; Demain, A.L.; Gomez, R.F.; Sinskey, A.J.

    1978-11-01

    Studies on the accumulation of glucose during the fermentation of cellulose by Clostridium thermocellum are discussed. Production of ethanol and its relationship to growth rate in C. thermocellum is reported. Different biomasses were tested for ethanol yields. These included exploded poplar, sugar cane, bagasse, corn cobs, sweet gum, rice straw, and wheat straw. Thermophilic bacteria were tested to determine relationship of temperature to yield of ethanol. A preliminary report on isolating plaque forming emits derived from C. thermocellum is presented as well as the utilization of carbohydrates in nutrition. A cellulose enzyme is being purified from C. thermocellum. The production of chemical feedstocks by fermentation is reported. Acrylic acid, acetone/butanol, and acetic acid, produced by C. propionicum, C. acetobutylicum, and C. thermoaceticum, are discussed. (DC)

  18. Steam reforming of ethanol

    DEFF Research Database (Denmark)

    Trane-Restrup, Rasmus; Dahl, Søren; Jensen, Anker Degn

    2013-01-01

    Steam reforming (SR) of oxygenated species like bio-oil or ethanol can be used to produce hydrogen or synthesis gas from renewable resources. However, deactivation due to carbon deposition is a major challenge for these processes. In this study, different strategies to minimize carbon deposition...

  19. Ethanol Forensic Toxicology.

    Science.gov (United States)

    Perry, Paul J; Doroudgar, Shadi; Van Dyke, Priscilla

    2017-12-01

    Ethanol abuse can lead to negative consequences that oftentimes result in criminal charges and civil lawsuits. When an individual is suspected of driving under the influence, law enforcement agents can determine the extent of intoxication by measuring the blood alcohol concentration (BAC) and performing a standardized field sobriety test. The BAC is dependent on rates of absorption, distribution, and elimination, which are influenced mostly by the dose of ethanol ingested and rate of consumption. Other factors contributing to BAC are gender, body mass and composition, food effects, type of alcohol, and chronic alcohol exposure. Because of individual variability in ethanol pharmacology and toxicology, careful extrapolation and interpretation of the BAC is needed, to justify an arrest and assignment of criminal liability. This review provides a summary of the pharmacokinetic properties of ethanol and the clinical effects of acute intoxication as they relate to common forensic questions. Concerns regarding the extrapolation of BAC and the implications of impaired memory caused by alcohol-induced blackouts are discussed. © 2017 American Academy of Psychiatry and the Law.

  20. Bio-ethanol

    DEFF Research Database (Denmark)

    Wenzel, Henrik

    2007-01-01

    , there is not enough biomass for 'everyone', not physically and not in terms of money to promote its use. This leads to the conclusion that any use of biomass for energy purposes will have to compare to the lost opportunity of using it for something else. In this perspective, the choice to use biomass for bio......-ethanol production will not lead to reduction but to increase in CO2 emission and fossil fuel dependency. Both first and second generation bio-ethanol suffer from a biomass-to-ethanol energy conversion efficiency as low as 30-40 %, and moreover external fossil fuels are used to run the conversion. There is only......, but they do not improve the energy balance enough for bio-ethanol to compete with alternative uses of the biomass. When using biomass to substitute fossil fuels in heat & power production, a close to 100% substitution efficiency is achieved. The best alternative for CO2 reduction and oil saving is, therefore...

  1. Alexa Fluor-labeled Fluorescent Cellulose Nanocrystals for Bioimaging Solid Cellulose in Spatially Structured Microenvironments

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.; Mo, Kai-For; Shin, Yongsoon; Vasdekis, Andreas; Warner, Marvin G.; Kelly, Ryan T.; Orr, Galya; Hu, Dehong; Dehoff, Karl J.; Brockman, Fred J.; Wilkins, Michael J.

    2015-03-18

    Cellulose nanocrystal materials have been labeled with modern Alexa Fluor dyes in a process that first links the dye to a cyanuric chloride molecule. Subsequent reaction with cellulose nanocrystals provides dyed solid microcrystalline cellulose material that can be used for bioimaging and suitable for deposition in films and spatially structured microenvironments. It is demonstrated with single molecular fluorescence microscopy that these films are subject to hydrolysis by cellulose enzymes.

  2. Cellulose powder from Cladophora sp. algae.

    Science.gov (United States)

    Ek, R; Gustafsson, C; Nutt, A; Iversen, T; Nyström, C

    1998-01-01

    The surface are and crystallinity was measured on a cellulose powder made from Cladophora sp. algae. The algae cellulose powder was found to have a very high surface area (63.4 m2/g, N2 gas adsorption) and build up of cellulose with a high crystallinity (approximately 100%, solid state NMR). The high surface area was confirmed by calculations from atomic force microscope imaging of microfibrils from Cladophora sp. algae.

  3. Alpha autoradiography by cellulose nitrate layer

    International Nuclear Information System (INIS)

    Simonovic, J.; Vukovic, J.; Antanasijevic, R.

    1977-01-01

    From domestic cellulose nitrate bulk material thin layers for α-particle autoradiography were prepared. An artificial test specimen of a uniformly alpha labelled grid source was used. The efficiency of autoradiography by cellulose nitrate was calculated comparing with data from an Ilford K2 nuclear emulsion exposed under the same conditions as the cellulose nitrate film. The resolution was determined as the distance from grid pitch edge at which the track density fell considerably. (Auth.)

  4. Alpha autoradiography by cellulose nitrate layer

    International Nuclear Information System (INIS)

    Simonovic, J.; Vukovic, J.; Antanasijevic, R.

    1976-01-01

    From domestic cellulose nitrate bulk material thin layers for α-particle autoradiography were prepared. An artifical test specimen of a uniformly alpha labelled grid source was used. The efficiency of autoradiographs by cellulose nitrate was calculated comparing with data from an Ilford K2 nuclear emulsion exposed under the same conditions as the cellulose nitrate film. The resolution was determined as the distance from grid pitch edge at which the track density fell considerably. (orig.) [de

  5. Sorghum to Ethanol Research

    Energy Technology Data Exchange (ETDEWEB)

    Dahlberg, Jeffrey A. [Univ. of California, Parlier, CA (United States). Kearney Research and Extension Center; Wolfrum, Edward J. [National Renewable Energy Lab. (NREL), Golden, CO (United States). Process and Analytical Engineering Group

    2010-09-28

    The development of a robust source of renewable transportation fuel will require a large amount of biomass feedstocks. It is generally accepted that in addition to agricultural and forestry residues, we will need crops grown specifically for subsequent conversion into fuels. There has been a lot of research on several of these so-called "dedicated bioenergy crops" including switchgrass, miscanthus, sugarcane, and poplar. It is likely that all of these crops will end up playing a role as feedstocks, depending on local environmental and market conditions. Many different types of sorghum have been grown to produce syrup, grain, and animal feed for many years. It has several features that may make it as compelling as other crops mentioned above as a renewable, sustainable biomass feedstock; however, very little work has been done to investigate sorghum as a dedicated bioenergy crop. The goal of this project was to investigate the feasibility of using sorghum biomass to produce ethanol. The work performed included a detailed examination of the agronomics and composition of a large number of sorghum varieties, laboratory experiments to convert sorghum to ethanol, and economic and life-cycle analyses of the sorghum-to-ethanol process. This work showed that sorghum has a very wide range of composition, which depended on the specific sorghum cultivar as well as the growing conditions. The results of laboratory- and pilot-scale experiments indicated that a typical high-biomass sorghum variety performed very similarly to corn stover during the multi-step process required to convert biomass feedstocks to ethanol; yields of ethanol for sorghum were very similar to the corn stover used as a control in these experiments. Based on multi-year agronomic data and theoretical ethanol production, sorghum can achieve more than 1,300 gallons of ethanol per acre given the correct genetics and environment. In summary, sorghum may be a compelling dedicated bioenergy crop that could help

  6. Monetary value of the environmental and health externalities associated with production of ethanol from biomass feedstocks

    International Nuclear Information System (INIS)

    Kusiima, Jamil M.; Powers, Susan E.

    2010-01-01

    This research is aimed at monetizing the life cycle environmental and health externalities associated with production of ethanol from corn, corn stover, switchgrass, and forest residue. The results of this study reveal current average external costs for the production of 1 l of ethanol ranged from $0.07 for forest residue to $0.57 for ethanol production from corn. Among the various feedstocks, the external costs of PM 10 , NO X , and PM 2.5 are among the greatest contributors to these costs. The combustion of fossil fuels in upstream fertilizer and energy production processes is the primary source of these emissions and their costs, especially for corn ethanol. The combined costs of emissions associated with the production and use of nitrogen fertilizer also contribute substantially to the net external costs. For cellulosic ethanol production, the combustion of waste lignin to generate heat and power helps to keep the external costs lower than corn ethanol. Credits both for the biogenic carbon combustion and displacement of grid electricity by exporting excess electricity substantially negate many of the emissions and external costs. External costs associated with greenhouse gas emissions were not significant. However, adding estimates of indirect GHG emissions from land use changes would nearly double corn ethanol cost estimates.

  7. Effects of alternative energy sources on bacterial cellulose characteristics produced by Komagataeibacter medellinensis.

    Science.gov (United States)

    Molina-Ramírez, Carlos; Enciso, Carla; Torres-Taborda, Mabel; Zuluaga, Robin; Gañán, Piedad; Rojas, Orlando J; Castro, Cristina

    2018-05-27

    Bacterial cellulose (BC) was produced by Komagataeibacter medellinensis using Hestrin and Schramm modified medium in the presence of alternative energy sources (AES), such as ethanol and acetic acid, to explore the effect of AES on the characteristics and properties of the resulting BC. In this study, the physicochemical and structural characteristics of the obtained BC were determined using Fourier-transform infrared spectroscopy, X-ray diffraction spectrometry, thermogravimetric analysis, and mechanical testing analysis. Ethanol and acetic acid (at 0.1 wt%) were proven to improve the BC yield by K. medellinensis by 279% and 222%, respectively. However, the crystallinity index (%), the degree of polymerization, and maximum rate of degradation temperatures decreased by 9.2%, 36%, and 4.96%, respectively, by the addition of ethanol and by 7.2%, 27%, and 4.21%, respectively, by the addition of acetic acid. The significance of this work, lies on the fact that there is not any report about how BC properties change when substances like ethanol or acetic acid are added to culture medium, and which is the mechanism that provokes those changes, that in our case we could demonstrate the relationship of a higher BC production rate (provoked by ethanol and acetic acid adding) and changes in BC properties. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Chemo-catalytic valorization of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Palkovits, R. [RWTH Aachen Univ. (Germany). Inst. fuer Technische und Makromolekulare Chemie

    2012-07-01

    Cellulose can be utilized as carbon source for the production of novel platform molecules as well as fuel motifs. Promising transformation strategies cover the hydrolytic hydrogenation or hydrogenolysis of cellulose to sugar alcohols, the hydrolysis of cellulose to glucose followed by dehydration to 5-hydroxymethylfurfural or levulinic acid and the further hydrogenation of levulinic acid to {gamma}-valerolactone. Main challenges result from the high degree of functionalization of cellulosic feedstocks. In line, processes are carried out in liquid phase utilizing rather polar solvents and aiming for a tailored defunctionalisation of these oxygen rich compounds. Consequently, such transformations require novel strategies concerning the development of suitable catalysts and appropriate process concepts. (orig.)

  9. Cellulose accessibility limits the effectiveness of minimum cellulase loading on the efficient hydrolysis of pretreated lignocellulosic substrates

    Directory of Open Access Journals (Sweden)

    Saddler Jack N

    2011-02-01

    Full Text Available Abstract A range of lignocellulosic feedstocks (including agricultural, softwood and hardwood substrates were pretreated with either sulfur dioxide-catalyzed steam or an ethanol organosolv procedure to try to establish a reliable assessment of the factors governing the minimum protein loading that could be used to achieve efficient hydrolysis. A statistical design approach was first used to define what might constitute the minimum protein loading (cellulases and β-glucosidase that could be used to achieve efficient saccharification (defined as at least 70% glucan conversion of the pretreated substrates after 72 hours of hydrolysis. The likely substrate factors that limit cellulose availability/accessibility were assessed, and then compared with the optimized minimum amounts of protein used to obtain effective hydrolysis. The optimized minimum protein loadings to achieve efficient hydrolysis of seven pretreated substrates ranged between 18 and 63 mg protein per gram of glucan. Within the similarly pretreated group of lignocellulosic feedstocks, the agricultural residues (corn stover and corn fiber required significantly lower protein loadings to achieve efficient hydrolysis than did the pretreated woody biomass (poplar, douglas fir and lodgepole pine. Regardless of the substantial differences in the source, structure and chemical composition of the feedstocks, and the difference in the pretreatment technology used, the protein loading required to achieve efficient hydrolysis of lignocellulosic substrates was strongly dependent on the accessibility of the cellulosic component of each of the substrates. We found that cellulose-rich substrates with highly accessible cellulose, as assessed by the Simons' stain method, required a lower protein loading per gram of glucan to obtain efficient hydrolysis compared with substrates containing less accessible cellulose. These results suggest that the rate-limiting step during hydrolysis is not the catalytic

  10. Potentiality of Yeasts in the Direct Conversion of Starchy Materials to Ethanol and Its Relevance in the New Millennium

    Science.gov (United States)

    Reddy, L. V. A.; Reddy, O. V. S.; Basappa, S. C.

    In recent years, the use of renewable and abundantly available starchy and cellulosic materials for industrial production of ethanol is gaining importance, in view of the fact, that ethanol is one of the most prospective future motor fuels, that can be expected to replace fossil fuels, which are fast depleting in the world scenario. Although, the starch and the starchy substrates could be converted successfully to ethanol on industrial scales by the use of commercial amylolytic enzymes and yeast fermentation, the cost of production is rather very high. This is mainly due to the non-enzymatic and enzymatic conversion (gelatinization, liquefaction and saccharification) of starch to sugars, which costs around 20 % of the cost of production of ethanol from starch. In this context, the use of amylolytic yeasts, that can directly convert starch to ethanol by a single step, are potentially suited to reduce the cost of production of ethanol from starch. Research advances made in this direction have shown encouraging results, both in terms of identifying the potentially suited yeasts for the purpose and also their economic ethanol yields. This chapter focuses on the types of starch and starchy substrates and their digestion to fermentable sugars, optimization of fermentation conditions to ethanol from starch, factors that affect starch fermentation, potential amylolytic yeasts which can directly convert starch to ethanol, genetic improvement of these yeasts for better conversion efficiency and their future economic prospects in the new millennium.

  11. Liquid crystalline solutions of cellulose in phosphoric acid for preparing cellulose yarns

    NARCIS (Netherlands)

    Boerstoel, H.

    2006-01-01

    The presen thesis describes a new process for manufacturing high tenacity and high modulus cellulose yarns. A new direct solvent for cellulose has been discovered, leading to liquid crystalline solutions. This new solvent, superphosphoric acid, rapidly dissolves cellulose. These liquid crystalline

  12. Incentives of Health Care Expenditure

    Directory of Open Access Journals (Sweden)

    Eero Siljander

    2012-12-01

    Full Text Available The incentives of health care expenditure (HCE have been a topic of discussion in the USA (Obama reforms and in Europe (adjustment to debt crisis. There are competing views of institutional versus GDP (unit income elasticity and productivity related factors of growth of expenditure. However ageing of populations, technology change and economic incentives related to institutions are also key drivers of growth according to the OECD and EU’s AWG committee. Simulation models have been developed to forecast the growth of social expenditure (including HCEs to 2050. In this article we take a historical perspective to look at the institutional structures and their relationship to HCE growth. When controlling for age structure, price developments, doctor density and in-patient and public shares of expenditures, we find that fee-for-service in primary care, is according to the results, in at least 20 percent more costly than capitation or salary remuneration. Capitation and salary (or wage remuneration are at same cost levels in primary care. However we did not find the cost lowering effect for gatekeeping which could have been expected based on previous literature. Global budgeting 30 (partly DRG based percent less costly in specialized care than other reimbursement schemes like open contracting or volume based reimbursement. However the public integration of purchaser and provider cost seems to result to about 20 higher than public reimbursement or public contracting. Increasing the number of doctors or public financing share results in increased HCEs. Therefore expanding public reimbursement share of health services seems to lead to higher HCE. On the contrary, the in-patient share reduced expenditures. Compared to the previous literature, the finding on institutional dummies is in line with similar modeling papers. However the results for public expansion of services is a contrary one to previous works on the subject. The median lag length of

  13. High Performance Regenerated Cellulose Membranes from Trimethylsilyl Cellulose

    KAUST Repository

    Ali, Ola

    2013-05-01

    Regenerated cellulose (RC) membranes are extensively used in medical and pharmaceutical separation processes due to their biocompatibility, low fouling tendency and solvent resistant properties. They typically possess ultrafiltration and microfiltration separation characteristics, but recently, there have been attempts to widen their pool of applications in nanofiltration processes. In this work, a novel method for preparing high performance composite RC membranes was developed. These membranes reveal molecular weight cut-offs (MWCO) of less than 250 daltons, which possibly put them ahead of all commercial RC membranes and in competition with high performance nanofiltration membranes. The membranes were prepared by acidic hydrolysis of dip-coated trimethylsilyl cellulose (TMSC) films. TMSC, with a degree of silylation (DS) of 2.8, was prepared from microcrystalline cellulose by reaction with hexamethyldisilazane under the homogeneous conditions of LiCl/DMAC solvent system. Effects of parameters, such as coating solution concentration and drying rates, were investigated. It was concluded that higher TMSC concentrations as well as higher solvent evaporation rates favor better MWCOs, mainly due to increase in the selective layer thickness. Successful cross-linking of prepared membranes with glyoxal solutions, in the presence of boric acid as a catalyst, resulted in MWCOs less than 250 daltons. The suitability of this crosslinking reaction for large scale productions was already proven in the manufacturing of durable-press fabrics. For us, the inexpensive raw materials as well as the low reaction times and temperatures were of interest. Moreover, the non-toxic nature of glyoxal is a key advantage in medical and pharmaceutical applications. The membranes prepared in this work are strong candidates for separation of small organic solutes from organic solvents streams in pharmaceutical industries. Their hydrophilicity, compared to typical nanofiltration membranes, offer

  14. An Update on Ethanol Production and Utilization in Thailand, 2014

    Energy Technology Data Exchange (ETDEWEB)

    Bloyd, Cary N.; Foster, Nikolas A.F.

    2014-09-01

    In spite of the recent political turmoil, Thailand has continued to develop its ethanol based alternative fuel supply and demand infrastructure. Its support of production and sales of ethanol contributed to more than doubling the production over the past five years alone. In April 2014, average consumption stood at 3.18 million liter per day- more than a third on its way to its domestic consumption goal of 9 million liters per day by 2021. Strong government incentives and the phasing out of non-blended gasoline contributed substantially. Concurrently, exports dropped significantly to their lowest level since 2011, increasing the pressure on Thai policy makers to best balance energy independency goals with other priorities, such as Thailand’s trade balance and environmental aspirations. Utilization of second generation biofuels might have the potential to further expand Thailand’s growing ethanol market. Thailand has also dramatically increased its higher ethanol blend vehicle fleet, with all new vehicles sold in the Thai market now being E20 capable and the number of E85 vehicles increasing three fold in the last year from 100,000 in 2013 to 300,000 in 2014.

  15. Bioconversion of different sizes of microcrystalline cellulose pretreated by microwave irradiation with/without NaOH

    International Nuclear Information System (INIS)

    Peng, Huadong; Chen, Hongzhang; Qu, Yongshui; Li, Hongqiang; Xu, Jian

    2014-01-01

    Highlights: • High concentration of alkali or temperature was necessary in cellulose degradation. • Effects of alkali pretreatment could be enhanced with the addition of microwave irradiation. • The structures diversities of microcrystalline cellulose were eliminated in the fermentation. • The significance of particle size and treat condition varied with reaction time. - Abstract: The process of microwave irradiation (MWI) pretreatment on microcrystalline cellulose (MCC) with different sizes with/without NaOH was investigated on the variation of the ratio of degradated solid residue (R DS ), particle size, crystallinity index (CrI), crystallite size (Sc) and specific surface area (SSA). High concentration of alkali or high temperature was necessary in dissolving or decomposing the cellulose. Appropriate pretreatment severity eliminated the effects of structural diversities in feedstocks, which led to convergence in the ethanol fermentation. After the reaction proceeded to 120 h, the samples could be converted to glucose completely and the highest ethanol yield of the theoretical was 58.91% for all the samples pretreated by the combined treatment of MWI and NaOH. In addition, the statistical analysis implied that when reaction time got to 24 h, particle size and pretreatment condition affected much more significant than other factors

  16. The food v. fuel debate. A nuanced view of incentive structures

    International Nuclear Information System (INIS)

    Srinivasan, Sunderasan

    2009-01-01

    The rapid rise in crude oil prices and the geo-political uncertainty associated with ensuring uninterrupted supplies have compelled researchers, economists and politicians to look for indigenous substitutes. Liquid biofuels - ethanol and biodiesel - are widely recognized, technically feasible alternatives. Even as the jury is out to determine the environmental footprint of biofuels, the surrounding frenzy has often led to the announcement of unsustainable support prices for feedstock and unviable procurement prices for the finished product. This paper makes a detailed assessment of incentive structures facing the agriculturists, refiners and the consumers. Data from the Indian market are employed to illustrate. (author)

  17. Cellulose-Hemicellulose Interactions at Elevated Temperatures Increase Cellulose Recalcitrance to Biological Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Mittal, Ashutosh [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Himmel, Michael E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kumar, Rajeev [University of California, Riverside; Oak Ridge National Laboratory; ; Smith, Micholas Dean [Oak Ridge National Laboratory; University of Tennessee; Petridis, Loukas [Oak Ridge National Laboratory; University of Tennessee; Ong, Rebecca G. [Michigan Technological University; Cai, Charles M. [University of California, Riverside; Oak Ridge National Laboratory; Balan, Venkatesh [University of Houston; Dale, Bruce E. [Michigan State University; Ragauskas, Arthur J. [Oak Ridge National Laboratory; University of Tennessee; Smith, Jeremy C. [Oak Ridge National Laboratory; University of Tennessee; Wyman, Charles E. [University of California, Riverside; Oak Ridge National Laboratory

    2018-01-23

    It has been previously shown that cellulose-lignin droplets' strong interactions, resulting from lignin coalescence and redisposition on cellulose surface during thermochemical pretreatments, increase cellulose recalcitrance to biological conversion, especially at commercially viable low enzyme loadings. However, information on the impact of cellulose-hemicellulose interactions on cellulose recalcitrance following relevant pretreatment conditions are scarce. Here, to investigate the effects of plausible hemicellulose precipitation and re-association with cellulose on cellulose conversion, different pretreatments were applied to pure Avicel(R) PH101 cellulose alone and Avicel mixed with model hemicellulose compounds followed by enzymatic hydrolysis of resulting solids at both low and high enzyme loadings. Solids produced by pretreatment of Avicel mixed with hemicelluloses (AMH) were found to contain about 2 to 14.6% of exogenous, precipitated hemicelluloses and showed a remarkably much lower digestibility (up to 60%) than their respective controls. However, the exogenous hemicellulosic residues that associated with Avicel following high temperature pretreatments resulted in greater losses in cellulose conversion than those formed at low temperatures, suggesting that temperature plays a strong role in the strength of cellulose-hemicellulose association. Molecular dynamics simulations of hemicellulosic xylan and cellulose were found to further support this temperature effect as the xylan-cellulose interactions were found to substantially increase at elevated temperatures. Furthermore, exogenous, precipitated hemicelluloses in pretreated AMH solids resulted in a larger drop in cellulose conversion than the delignified lignocellulosic biomass containing comparably much higher natural hemicellulose amounts. Increased cellulase loadings or supplementation of cellulase with xylanases enhanced cellulose conversion for most pretreated AMH solids; however, this approach

  18. Pyrolytic sugars from cellulosic biomass

    Science.gov (United States)

    Kuzhiyil, Najeeb

    Sugars are the feedstocks for many promising advanced cellulosic biofuels. Traditional sugars derived from starch and sugar crops are limited in their availability. In principle, more plentiful supply of sugars can be obtained from depolymerization of cellulose, the most abundant form of biomass in the world. Breaking the glycosidic bonds between the pyranose rings in the cellulose chain to liberate glucose has usually been pursued by enzymatic hydrolysis although a purely thermal depolymerization route to sugars is also possible. Fast pyrolysis of pure cellulose yields primarily levoglucosan, an anhydrosugar that can be hydrolyzed to glucose. However, naturally occurring alkali and alkaline earth metals (AAEM) in biomass are strongly catalytic toward ring-breaking reactions that favor formation of light oxygenates over anhydrosugars. Removing the AAEM by washing was shown to be effective in increasing the yield of anhydrosugars; but this process involves removal of large amount of water from biomass that renders it energy intensive and thereby impractical. In this work passivation of the AAEM (making them less active or inactive) using mineral acid infusion was explored that will increase the yield of anhydrosugars from fast pyrolysis of biomass. Mineral acid infusion was tried by previous researchers, but the possibility of chemical reactions between infused acid and AAEM in the biomass appears to have been overlooked, possibly because metal cations might be expected to already be substantially complexed to chlorine or other strong anions that are found in biomass. Likewise, it appears that previous researchers assumed that as long as AAEM cations were in the biomass, they would be catalytically active regardless of the nature of their complexion with anions. On the contrary, we hypothesized that AAEM can be converted to inactive or less active salts using mineral acids. Various biomass feedstocks were infused with mineral (hydrochloric, nitric, sulfuric and

  19. Value-added biotransformation of cellulosic sugars by engineered Saccharomyces cerevisiae.

    Science.gov (United States)

    Lane, Stephan; Dong, Jia; Jin, Yong-Su

    2018-07-01

    The substantial research efforts into lignocellulosic biofuels have generated an abundance of valuable knowledge and technologies for metabolic engineering. In particular, these investments have led to a vast growth in proficiency of engineering the yeast Saccharomyces cerevisiae for consuming lignocellulosic sugars, enabling the simultaneous assimilation of multiple carbon sources, and producing a large variety of value-added products by introduction of heterologous metabolic pathways. While microbial conversion of cellulosic sugars into large-volume low-value biofuels is not currently economically feasible, there may still be opportunities to produce other value-added chemicals as regulation of cellulosic sugar metabolism is quite different from glucose metabolism. This review summarizes these recent advances with an emphasis on employing engineered yeast for the bioconversion of lignocellulosic sugars into a variety of non-ethanol value-added products. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Evaluation of Potential Fungal Species for the in situ Simultaneous Saccharification and Fermentation (SSF of Cellulosic Material

    Directory of Open Access Journals (Sweden)

    Leeuwen, J.

    2011-01-01

    Full Text Available Three fungal species were evaluated for their abilities to saccharify pure cellulose. The three species chosen represented three major wood-rot molds; brown rot (Gloeophyllum trabeum, white rot (Phanerochaete chrysosporium and soft rot (Trichoderma reesei. After solid state fermentation of the fungi on the filter paper for four days, the saccharified cellulose was then fermented to ethanol by using Saccharomyces cerevisiae. The efficiency of the fungal species in saccharifying the filter paper was compared against a low dose (25 FPU/g cellulose of a commercial cellulase. Total sugar, cellobiose and glucose were monitored during the fermentation period, along with ethanol, acetic acid and lactic acid. Results indicated that the most efficient fungal species in saccharifying the filter paper was T. reesei with 5.13 g/100 g filter paper of ethanol being produced at days 5, followed by P. chrysosporium at 1.79 g/100 g filter paper. No ethanol was detected for the filter paper treated with G. trabeum throughout the five day fermentation stage. Acetic acid was only produced in the sample treated with T. reesei and the commercial enzyme, with concentration 0.95 and 2.57 g/100 g filter paper, respectively at day 5. Lactic acid production was not detected for all the fungal treated filter paper after day 5. Our study indicated that there is potential in utilizing in situ enzymatic saccharification of biomass by using T. reesei and P. chrysosporium that may lead to an economical simultaneous saccharification and fermentation process for the production of fuel ethanol.