WorldWideScience

Sample records for cellulosic ethanol securing

  1. Cellulosic Ethanol: Securing the Planet Future Energy Needs

    Directory of Open Access Journals (Sweden)

    Hannah Uckelmann

    2008-05-01

    Full Text Available Bioenergy is fairly recognized as not only a necessity, but an inevitable path to secure the planet future energy needs. There is however a global consensus that the overall feasibility of bioenergy will require an integrated approach based on diversified feedstocks and conversion processes. As illustrated in the Brazilian experience, the thrust of any bioenergy program should be centered on the principles and criteria of sustainable production. In general the trends are towards exploiting low value cellulosic materials to obtain high-end value energy products. To this end, it is expected that scientific or technical innovation will come to play a critical role on the future prospects and potential of any bioenergy initiative.

  2. 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...... differences in removal of hemicellulose, accumulation of ash and particle-size distribution introduced by the pretreatment. --------------------------------------------------------------------------------...

  3. [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. PMID:25212000

  4. 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.

  5. 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.

  6. Prospects for Irradiation in Cellulosic Ethanol Production

    Directory of Open Access Journals (Sweden)

    Anita Saini

    2015-01-01

    Full Text Available Second generation bioethanol production technology relies on lignocellulosic biomass composed of hemicelluloses, celluloses, and lignin components. Cellulose and hemicellulose are sources of fermentable sugars. But the structural characteristics of lignocelluloses pose hindrance to the conversion of these sugar polysaccharides into ethanol. The process of ethanol production, therefore, involves an expensive and energy intensive step of pretreatment, which reduces the recalcitrance of lignocellulose and makes feedstock more susceptible to saccharification. Various physical, chemical, biological, or combined methods are employed to pretreat lignocelluloses. Irradiation is one of the common and promising physical methods of pretreatment, which involves ultrasonic waves, microwaves, γ-rays, and electron beam. Irradiation is also known to enhance the effect of saccharification. This review explains the role of different radiations in the production of cellulosic ethanol.

  7. Prospects for Irradiation in Cellulosic Ethanol Production.

    Science.gov (United States)

    Saini, Anita; Aggarwal, Neeraj K; Sharma, Anuja; Yadav, Anita

    2015-01-01

    Second generation bioethanol production technology relies on lignocellulosic biomass composed of hemicelluloses, celluloses, and lignin components. Cellulose and hemicellulose are sources of fermentable sugars. But the structural characteristics of lignocelluloses pose hindrance to the conversion of these sugar polysaccharides into ethanol. The process of ethanol production, therefore, involves an expensive and energy intensive step of pretreatment, which reduces the recalcitrance of lignocellulose and makes feedstock more susceptible to saccharification. Various physical, chemical, biological, or combined methods are employed to pretreat lignocelluloses. Irradiation is one of the common and promising physical methods of pretreatment, which involves ultrasonic waves, microwaves, γ-rays, and electron beam. Irradiation is also known to enhance the effect of saccharification. This review explains the role of different radiations in the production of cellulosic ethanol. PMID:26839707

  8. 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 ...

  9. Effects of Ethanol Pulping on the Length of Bamboo Cellulose

    Institute of Scientific and Technical Information of China (English)

    Tao Yang; Liao Junhe; Luo Xuegang

    2006-01-01

    On the conditions of different ethanol concentration, acids and catalyzers, the effects of ethanol pulping on the cellulose length of bamboo were studied. The results indicates that ethanol pulping has remarkable effects on the length of cellulose, which is clearly reduced with adding ethanol and acid. The margin of length of cellulose become smaller with the increase of the catalyzer. When the ethanol concentration was 70%, the concentration of acid was 0.3% and some NaOH was used as catalyzer, the length of cellulose was the longest.

  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. NREL Proves Cellulosic Ethanol Can Be Cost Competitive (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2013-11-01

    Ethanol from non-food sources - known as "cellulosic ethanol" - is a near-perfect transportation fuel: it is clean, domestic, abundant, and renewable, and it can potentially replace 30% of the petroleum consumed in the United States, but its relatively high cost has limited its market. That changed in 2012, when the National Renewable Energy Laboratory (NREL) demonstrated the technical advances needed to produce cellulosic ethanol at a minimum ethanol selling price of $2.15/gallon (in 2007 dollars). Through a multi-year research project involving private industry, NREL has proven that cellulosic ethanol can be cost competitive with other transportation fuels.

  12. 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.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  15. ethanol production from cellulosic wastes using irradiated microorganisms

    International Nuclear Information System (INIS)

    saccharomyces cerevisiae, y10 was selected as the most potent isolate for fermentation process in this study, maximum ethanol production was recorder from NH4-pretreated bagasse, followed by HCl-pretreated CHW (cellulosic hospital wastes), while rice straw pretreated with H2O2 recorded reasonable production under simultaneous saccharification and fermentation (SSF) process which was found to be the preferable tested technique (technique I). hemicellulose of the three mentioned pretreated cellulosic substrates was more easily broken than cellulose and lignin . the ethanol productivity was maximal at substrate concentration of 4 ,8 and 5% (w/v) for rice straw, bagasse and CHIW respectively . the maximum ethanol yield was represented at a ratio 1:4 for (rice straw : H2O2 and bagasse : NH4) and 1:2 for (CHIW:HCl) . pretreated cellulosic substrates recorded maximum production at 8 N H2O2, 0.5 N NH4 and 4 N HCl for rice straw,bagasse and CHIW respectively . 40% filtrate overliming detoxification achieved the highest ethanol productivity from chemically pretreated rice straw, while tween 60 at 0.5 % (w/v) achieved maximum production from both pretreated bagasse and CHIW

  16. Biofuel Food Disasters and Cellulosic Ethanol Problems

    Science.gov (United States)

    Pimentel, David

    2009-01-01

    As shortages of fossil energy, especially oil and natural gas, become evident, the United States has moved to convert corn grain into ethanol with the goal to make the nation oil independent. Using more than 20% of all U.S. corn on 15 million acres in 2007 was providing the nation with less than 1% of U.S. oil consumption. Because the corn ethanol…

  17. 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

  18. CELLULOSIC ETHANOL VIA BIOCHEMICAL PROCESSING POSES A CHALLENGE FOR DEVELOPERS AND IMPLEMENTORS

    Directory of Open Access Journals (Sweden)

    Ilkka Virkajärvi

    2009-11-01

    Full Text Available In the future liquid biofuels will need to be renewable, sustainable, as well as technically and economically viable. This paper provides an overview of the challenges that the biochemical production of cellulosic ethanol process still faces. The main emphasis of the paper is on challenges that emerge from the scale of liquid biofuel production. These challenges include raw material availability, other consumables, and side stream handling. The pretreatment, C5 fermentation, and concentration of sugars in processing need improvements, too. Sustainability issues and greenhouse gas reduction also pose a challenge for implementation and require development of internationally recognized sustainability principles and standards, and certification of sustainable operation. Economics of cellulosic ethanol processes are still also an area under development and debate. Yet, the Energy Independence and Security Act mandate together with the European Union Renewable Energy Directive and other local targets are driving the development and implementation forward towards more significant contribution of biofuels in the transportation sector.

  19. Extraction of cellulose with subcritical and supercritical ethanol

    Institute of Scientific and Technical Information of China (English)

    Qian Xueren; Li Jian

    1999-01-01

    Cotton cellulose was extracted with ethanol in sub-and supercritical states dynamically. The degree of conversion was 95.4% and the extract yield was 55.2% when cotton cellulose was non-isothermally extracted with ethanol from 20℃ to 400℃. From an engineering standpoint, in the temperature range from 200℃ to 320℃,the rate of extract formation could adequately be described by a second-order reaction kinetics equation with the activation energy of 105.3 k J/mol and the pre-exponential factor of 3.53 × 107 s-1. With the non-isothermal experimental technique, it was possible to determine the kinetic parameters; conversion degree and extract yield by one experiment.

  20. 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.

  1. Review: Continuous hydrolysis and fermentation for cellulosic ethanol production.

    Science.gov (United States)

    Brethauer, Simone; Wyman, Charles E

    2010-07-01

    Ethanol made biologically from a variety of cellulosic biomass sources such as agricultural and forestry residues, grasses, and fast growing wood is widely recognized as a unique sustainable liquid transportation fuel with powerful economic, environmental, and strategic attributes, but production costs must be competitive for these benefits to be realized. Continuous hydrolysis and fermentation processes offer important potential advantages in reducing costs, but little has been done on continuous processing of cellulosic biomass to ethanol. As shown in this review, some continuous fermentations are now employed for commercial ethanol production from cane sugar and corn to take advantage of higher volumetric productivity, reduced labor costs, and reduced vessel down time for cleaning and filling. On the other hand, these systems are more susceptible to microbial contamination and require more sophisticated operations. Despite the latter challenges, continuous processes could be even more important to reducing the costs of overcoming the recalcitrance of cellulosic biomass, the primary obstacle to low cost fuels, through improving the effectiveness of utilizing expensive enzymes. In addition, continuous processing could be very beneficial in adapting fermentative organisms to the wide range of inhibitors generated during biomass pretreatment or its acid catalyzed hydrolysis. If sugar generation rates can be increased, the high cell densities in a continuous system could enable higher productivities and yields than in batch fermentations. PMID:20006926

  2. 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."

  3. 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.

  4. Simultaneous saccharification and fermentation of cellulose to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Shea, P.T.

    1981-01-01

    Simultaneous saccharification and fermentation (SSF) of cullulose (untreated BW-200 Solka Floc) to ethanol utilizing the cellulase enzyme complex of Trichoderma reesei Rut C-30 and the yeast Saccharomyces cerevisiae QM 8226, has resulted in increased rates and longer times of hydrolysis when compared to simple saccharifications. Additionally, two schemes for ethanol removal during hydrolysis, nitrogen sparging and vacuum operation, have also shown increased rates and longer times of saccharification of cellulose when compared to the simple SSF. Both early and delayed yeast additions, different lengths of SSF operations, and different sparging techniques were investigated. The beta-glucosidase fraction of the T. ressei Rut C-30 cellulase enzyme system was able to convert cellobiose to glucose in the presence of ethyl alcohol eliminating the strong inhibition of celloboise on cellulase while the yeast converted glucose to ethanol by glucolysis eliminating the inhibition of glucose on beta-glucosidase. The hydrolysis curves did not fit either simple or competitive product inhibition Michaelis-Menten type kinetic analysis. An enzyme deactivation-inhibition model seems necessary to fit the data. The yield parameter for ethanol/substrate (Yp/s) varied from .42g/g to .47g/g (theoretical .51g/g) with the majority of glucose being converted to ethanol in less than 15 hours.

  5. Using Cellulosic Ethanol to ‘Go Green’: What Price for Carbon?

    OpenAIRE

    Miranowski, John A.; Rosburg, Alicia

    2010-01-01

    The revised Renewable Fuels Standard (RFS2) mandates that cellulosic biofuels be part of the liquid transportation fuel mix and contribute to reducing our carbon footprint. Unfortunately, since no commercial cellulosic biorefinery exists and cellulosic biomass production is typically smaller scale than conventional crop production, limited knowledge exists of the actual costs of producing cellulosic biomass and converting it to cellulosic ethanol. Understanding of the implications of RFS2 req...

  6. 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. PMID:26966011

  7. The potential of cellulosic ethanol production from grasses in Thailand.

    Science.gov (United States)

    Wongwatanapaiboon, Jinaporn; Kangvansaichol, Kunn; Burapatana, Vorakan; Inochanon, Ratanavalee; Winayanuwattikun, Pakorn; Yongvanich, Tikamporn; Chulalaksananukul, Warawut

    2012-01-01

    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). PMID:23097596

  8. 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...

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

    OpenAIRE

    Qiong Song; William T. Winter; Biljana M. Bujanovic; Thomas E. Amidon

    2014-01-01

    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 e...

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

    International Nuclear Information System (INIS)

    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

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

    DEFF Research Database (Denmark)

    Cannella, David

    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...

  12. Cellulosic ethanol production from agricultural residues in Nigeria

    International Nuclear Information System (INIS)

    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 km3 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 km3 per annum respectively. - Highlights: • Nigeria′s Biofuels Policy mandates a 10% blend of bioethanol with gasoline. • Total bioethanol production from agricultural residues was 7556 km3 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

  13. 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.

  14. 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 ...

  15. Determining the Optimal Location for Collocating a Louisiana Sugar Mill and a New Cellulosic Ethanol Plant

    OpenAIRE

    Darby, Paul M.; Mark, Tyler B.

    2012-01-01

    This paper examines the possibility of collocating a cellulosic ethanol processing plant with certain Louisiana sugar mills, chosen based on their strategic locations and cane grinding capacity. The prospective plants are compared based on transportation costs and overall economic performance.

  16. 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

  17. Challenges of cellulosic ethanol production from xylose-extracted corncob residues

    Science.gov (United States)

    Xylose production using corncobs is an established industrial practice. The cellulose-rich xylose-extracted corncob residue (X-ER), as a byproduct, is a potential energy resource. Efforts to convert the cellulose fraction of X-ER to ethanol have been unsatisfactory due to a lack of understanding of ...

  18. Stochastic molecular model of enzymatic hydrolysis of cellulose for ethanol production

    OpenAIRE

    Kumar, Deepak; Murthy, Ganti S.

    2013-01-01

    Background During cellulosic ethanol production, cellulose hydrolysis is achieved by synergistic action of cellulase enzyme complex consisting of multiple enzymes with different mode of actions. Enzymatic hydrolysis of cellulose is one of the bottlenecks in the commercialization of the process due to low hydrolysis rates and high cost of enzymes. A robust hydrolysis model that can predict hydrolysis profile under various scenarios can act as an important forecasting tool to improve the hydrol...

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

    International Nuclear Information System (INIS)

    There is mounting concern about the buildup of carbon dioxide (CO2) 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

  20. Lower-cost cellulosic ethanol production using cellobiose fermenting yeast Clavispora NRRL Y-50464

    Science.gov (United States)

    For ethanol production from cellulosic materials, there are generally two major steps needed including enzymatic hydrolysis to break down biomass sugars and microbial fermentation to convert available simple sugars into ethanol. It often requires two different kinds of microorganisms since ethanolog...

  1. 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.

  2. Preliminary Economics for the Production of Pyrolysis Oil from Lignin in a Cellulosic Ethanol Biorefinery

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Susanne B.; Zhu, Yunhua

    2009-04-01

    Cellulosic ethanol biorefinery economics can be potentially improved by converting by-product lignin into high valued products. Cellulosic biomass is composed mainly of cellulose, hemicellulose and lignin. In a cellulosic ethanol biorefinery, cellulose and hemicellullose are converted to ethanol via fermentation. The raw lignin portion is the partially dewatered stream that is separated from the product ethanol and contains lignin, unconverted feed and other by-products. It can be burned as fuel for the plant or can be diverted into higher-value products. One such higher-valued product is pyrolysis oil, a fuel that can be further upgraded into motor gasoline fuels. While pyrolysis of pure lignin is not a good source of pyrolysis liquids, raw lignin containing unconverted feed and by-products may have potential as a feedstock. This report considers only the production of the pyrolysis oil and does not estimate the cost of upgrading that oil into synthetic crude oil or finished gasoline and diesel. A techno-economic analysis for the production of pyrolysis oil from raw lignin was conducted. comparing two cellulosic ethanol fermentation based biorefineries. The base case is the NREL 2002 cellulosic ethanol design report case where 2000 MTPD of corn stover is fermented to ethanol (NREL 2002). In the base case, lignin is separated from the ethanol product, dewatered, and burned to produce steam and power. The alternate case considered in this report dries the lignin, and then uses fast pyrolysis to generate a bio-oil product. Steam and power are generated in this alternate case by burning some of the corn stover feed, rather than fermenting it. This reduces the annual ethanol production rate from 69 to 54 million gallons/year. Assuming a pyrolysis oil value similar to Btu-adjusted residual oil, the estimated ethanol selling price ranges from $1.40 to $1.48 (2007 $) depending upon the yield of pyrolysis oil. This is considerably above the target minimum ethanol selling

  3. Air Emissions and Health Benefits from Using Sugarcane Waste as a Cellulosic Ethanol Feedstock

    Science.gov (United States)

    Tsao, C.; Campbell, E.; Chen, Y.; Carmichael, G.; Mena-Carrasco, M.; Spak, S.

    2010-12-01

    Brazil, as the largest ethanol exporter in the world, faces rapid expansion of ethanol production due to the increase of global biofuels demand. Current production of Brazilian sugarcane ethanol causes significant air emissions mainly from the open burning phase of agriculture wastes (i.e. sugarcane straws and leaves) resulting in potential health impacts. One possible measure to avoid undesired burning practices is to increase the utilization of unburned sugarcane residues as a feedstock for cellulosic ethanol. To explore the benefits of this substitution, here we first apply a bottom-up approach combining agronomic data and life-cycle models to investigate spatially and temporally explicit emissions from sugarcane waste burning. We further quantify the health benefits from preventing burning practices using the CMAQ regional air quality model and the BenMAP health benefit analysis tool adapted for Brazilian applications. Furthermore, the health impacts will be converted into monetary values which provide policymakers useful information for the development of cellulosic ethanol.

  4. 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.

  5. 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. PMID:19412687

  6. 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. PMID:27103854

  7. Quantitative Trait Loci and Trait Correlations for Maize Stover Cell Wall Composition and Glucose Release for Cellulosic Ethanol

    Science.gov (United States)

    In cellulosic ethanol production, the efficiency of converting maize (Zea mays L.) stover into fermentable sugars partly depends on the stover cell wall structure. Breeding for improved stover quality for cellulosic ethanol may benefit from the use of molecular markers. However, limited quantitative...

  8. 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).

  9. SYNTHESIS AND CHARACTERIZATION OF CELLULOSE-SILICA COMPOSITE FIBER IN ETHANOL/WATER MIXED SOLVENTS

    Directory of Open Access Journals (Sweden)

    Ning Jia

    2011-04-01

    Full Text Available Cellulose-silica composite fiber samples have been successfully synthesized using cellulose solution, tetraethoxysilane, and NH3•H2O in ethanol/water mixed solvents at room temperature for 24 h. The cellulose solution was previously prepared by the dissolution of microcrystalline cellulose in a solvent mixture of N,N-dimethylacetamide (DMAc/lithium chloride (LiCl. The effect of the tetraethoxysilane concentration on the product was investigated. The products were characterized by X-ray powder diffraction (XRD, thermogravimetric analysis (TG, differential scanning calorimetric analysis (DSC, scanning electron microscopy (SEM, Fourier transform infrared spectrometry (FT-IR, energy-dispersive X-ray spectrum (EDS, and cross polarization magic angle spinning (CP/MAS solid state 13C-NMR. The morphology of the cellulose-silica composite fiber was investigated by SEM, while their composition was established from EDS measurements combined with the results of FT-IR spectral analysis and XRD patterns. The XRD, FT-IR and EDS results indicated that the obtained product was cellulose-silica composite fiber. The SEM micrographs showed that the silica particles were homogeneously dispersed in the cellulose fiber. The CP/MAS solid state 13C-NMR results indicated that the silica concentration had an influence on the crystallinity of the cellulose. This method is simple for preparation of cellulose-based composites.

  10. Study of bio-ethanol production from cellulosic waste (rice straw)

    OpenAIRE

    Tadayosi, YOSHIMURA; Marie, HATAKAWA; Fumio, TAKAHASHI; Takatoshi, KAWASHIMA

    2012-01-01

    This basic research was carried out on bio-ethanol derived from cellulosic waste (rice straw). In view of the fact that rice straw is incorporated into the soil after harvesting the grains to increase mineral soil content, we examined the option of using high pressure pretreatment which does not involve chemical treatment, thus allowing residues from bio-ethanol production to be returned to the soil as a liquid fertilizer. Results from this study showed that i) high-pressure treatment enhance...

  11. 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.

  12. Understanding the Growth of the Cellulosic Ethanol Industry

    Energy Technology Data Exchange (ETDEWEB)

    Sandor, D.; Wallace, R.; Peterson, S.

    2008-04-01

    This report identifies, outlines, and documents a set of plausible scenarios for producing significant quantities of lignocellulosic ethanol in 2017. These scenarios can provide guidance for setting government policy and targeting government investment to the areas with greatest potential impact.

  13. Understanding the Growth of the Cellulosic Ethanol Industry

    Energy Technology Data Exchange (ETDEWEB)

    Sandor, D. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wallace, R. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Peterson, S. [Peterson Group, Anchorage, AK (United States)

    2008-04-01

    Report identifies and documents plausible scenarios for producing significant quantities of lignocellulosic ethanol in 2017 as a guide for setting government policy and targeting government investment to areas with greatest potential impact.

  14. Cellulosic Ethanol Production from Sugarcane Baggase without Enzymatic Saccharification

    OpenAIRE

    Raj Boopathy; Letha Dawson

    2008-01-01

    Sugarcane processing generates a large volume of bagasse. Disposal of bagasse is critical for both agricultural profitability and environmental protection. Sugarcane bagasse is a renewable resource that can be used to produce ethanol and many other value added products. In this study, we demonstrate that cane processed bagasse could be used to produce fuel grade ethanol without saccharification. A chemical pre-treatment process using alkaline peroxide and acid hydrolysis was applied to re...

  15. 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.)

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

    International Nuclear Information System (INIS)

    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 CO2. ► 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

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    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...

  18. Life Cycle Assessment of Switchgrass Cellulosic Ethanol Production in the Wisconsin and Michigan Agricultural Contexts

    Energy Technology Data Exchange (ETDEWEB)

    Sinistore, Julie C.; Reinemann, D. J.; Izaurralde, Roberto C.; Cronin, Keith R.; Meier, Paul J.; Runge, Troy M.; Zhang, Xuesong

    2015-04-25

    Spatial variability in yields and greenhouse gas emissions from soils has been identified as a key source of variability in life cycle assessments (LCAs) of agricultural products such as cellulosic ethanol. This study aims to conduct an LCA of cellulosic ethanol production from switchgrass in a way that captures this spatial variability and tests results for sensitivity to using spatially averaged results. The Environment Policy Integrated Climate (EPIC) model was used to calculate switchgrass yields, greenhouse gas (GHG) emissions, and nitrogen and phosphorus emissions from crop production in southern Wisconsin and Michigan at the watershed scale. These data were combined with cellulosic ethanol production data via ammonia fiber expansion and dilute acid pretreatment methods and region-specific electricity production data into an LCA model of eight ethanol production scenarios. Standard deviations from the spatial mean yields and soil emissions were used to test the sensitivity of net energy ratio, global warming potential intensity, and eutrophication and acidification potential metrics to spatial variability. Substantial variation in the eutrophication potential was also observed when nitrogen and phosphorus emissions from soils were varied. This work illustrates the need for spatially explicit agricultural production data in the LCA of biofuels and other agricultural products.

  19. 纤维素乙醇产业进展%Industry Progress of Cellulosic Ethanol

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    燃料乙醇已发展成为世界可再生能源产业之一,在经济、环境、能源等领域发挥着重要作用。利用能量及环境效益更佳的木质纤维素作为原料生产燃料乙醇,已是这一产业可持续发展的基石。自2014年下半年开始剧烈下跌的原油价格虽然带来了一些不确定因素,但在政策性因素引导下,世界燃料乙醇产业有序发展,在年产量创出新高的同时,纤维素乙醇示范装置也在加速建设。2017年纤维素乙醇生产能力有望突破100万吨。本文在综述世界燃料乙醇产业发展现状基础上,详细介绍了纤维素乙醇的产业进展,并对纤维素乙醇的发展趋势作了展望。%Fuel ethanol has become one of the world's renewable energy industries, and plays an important role in areas such as economy, environment and energy. To use lignocellulose with good energy efficient and environment benefit as raw material to produce fuel ethanol has become a footstone for the sustainable development of the fuel ethanol industry. Although sharp decrease of crude oil price has brought some uncertainties in the second half of 2014, the world ethanol industry continued development with positive policies. Not only the annual production set a new record, but also the construction of cellulosic ethanol commercial facilities accelerated. It is expected that the cellulosic ethanol production capacity will exceed 1 million tons in 2017. In this paper, current status of the fuel ethanol industry was introduced, progress of the cellulosic ethanol industry was reviewed, and development trend of the cellulosic ethanol industry is also discussed.

  20. Fuel-cycle fossil energy use and greenhouse gas emissions of corn and cellulosic ethanol

    International Nuclear Information System (INIS)

    The use of corn-based ethanol as an automotive fuel to displace petroleum-based gasoline in an effort to reduce greenhouse gas (GHG) emissions was discussed. Some past studies have shown increased GHG emissions from corn ethanol when energy use and emissions by up-stream production activities for corn ethanol were taken into account. Other studies have shown that the use of ethanol reduces GHG emissions. In this study, a thorough analysis of fuel-cycle energy use and GHG emissions of corn ethanol was conducted. The major issues under study were: (1) energy and chemical use intensity of corn farming, (2) N2O emissions from nitrogen fertilizer in corn fields, (3) energy use intensity at ethanol plants, and (4) energy and emission credits of co-products of corn ethanol. Results showed that the use of E85 from corn reduces fossil energy use by 35 to 40 per cent compared to gasoline and GHG are reduced by 16 to 28 per cent. Fuel-cycle energy and GHG emission impacts of cellulosic ethanol was also examined. It was shown that the use of E85 produced from biomass reduces fossil energy use by 80 per cent and eliminates GHG emissions of petroleum-based gasoline. 1 tab., 11 figs

  1. Cellulosic Ethanol Production by Recombinant Cellulolytic Bacteria Harbouring pdc and adh II Genes of Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    P. Sobana Piriya

    2012-01-01

    Full Text Available The ethanol fermenting genes such as pyruvate decarboxylase (pdc and alcohol dehydrogenase II (adh II were cloned from Zymomonas mobilis and transformed into three different cellulolytic bacteria, namely Enterobacter cloacae JV, Proteus mirabilis JV and Erwinia chrysanthemi and their cellulosic ethanol production capability was studied. Recombinant E. cloacae JV was found to produce 4.5% and 3.5% (v/v ethanol, respectively, when CMC and 4% NaOH pretreated bagasse were used as substrates, whereas recombinant P. mirabilis and E. chrysanthemi with the same substrates could only produce 4%, 3.5%, 1%, and 1.5 % of ethanol, respectively. The recombinant E. cloacae strain produced twofold higher percentage of ethanol than the wild type. The recombinant E. cloacae strain could be improved further by increasing its ethanol tolerance capability through media optimization and also by combining multigene cellulase expression for enhancing ethanol production from various types of lignocellulosic biomass so that it can be used for industrial level ethanol production.

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

    DEFF Research Database (Denmark)

    Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2010-01-01

    In order to lower the costs for second generation bioethanol from lignocellulosic biomass anaerobic digestion of the effluent from ethanol fermentation was implemented using an upflow anaerobic sludge blanket (UASB) reactor system in a pilot-scale biorefinery plant. Both thermophilic (538C......) 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...... were, however, higher under mesophilic conditions compared to thermophilic conditions. The conversion of dissolved organic matter (VSdiss) was between 68% and 91%. The effluent from the ethanol fermentation showed no signs of toxicity to the anaerobic microorganisms. However, a high content...

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

    International Nuclear Information System (INIS)

    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)

  4. Functional genomic studies lead in situ detoxification of fermentation inhibitors for low-cost cellulosic ethanol production

    Science.gov (United States)

    Renewable biomass, including lignocellulosic materials and agricultural residues, are low-cost materials for bioethanol production. However, significant challenges exist for efficient cost-effective conversion of cellulosic ethanol. One technical barrier is the stress conditions caused by toxic co...

  5. Automated Yeast Mating Protocol Using Open Reading Frames from Saccharomyces cerevisiae Genome to Improve Yeast Strains for Cellulosic Ethanol Production

    Science.gov (United States)

    Engineering the industrial ethanologen Saccharomyces cerevisiae to utilize pentose sugars from lignocellulosic biomass is critical for commercializing cellulosic fuel ethanol production. Approaches to engineer pentose-fermenting yeasts have required expression of additional genes. We implemented a...

  6. 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.

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

    OpenAIRE

    Madan Bhawna; Tsai Shen-Long; Goyal Garima; DaSilva Nancy A; Chen Wilfred

    2011-01-01

    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 yeas...

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

    Science.gov (United States)

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

    2016-01-01

    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. PMID:26685114

  9. The Potential of Cellulosic Ethanol Production from Municipal Solid Waste: A Technical and Economic Evaluation

    OpenAIRE

    Shi, Jian; Ebrik, Mirvat; Yang, Bin; Wyman, Charles E

    2009-01-01

    Municipal solid waste (MSW) is an attractive cellulosic resource for sustainable production of transportation fuels and chemicals because of its abundance, the need to find uses for this problematic waste, and its low and perhaps negative cost. However, significant heterogeneity and possible toxic contaminants are barriers to biological conversion to ethanol and other products. In this study, we obtained six fractions of sorted MSW from a waste processing facility in Fontana, California: 1) f...

  10. 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

    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 into...

  11. Lower-cost cellulosic ethanol production from corn stover using ß-glucosidase producing yeast Clavispora NRRL Y-50464

    Science.gov (United States)

    For cellulosic ethanol production, decomposition of cellulosic polymers and enzymatic hydrolysis and saccharification are necessary for microbes to efficiently utilize the biomass harbored sugars. The need of additional enzymes and processing steps increase cost of biofuels. To reduce the cost of ce...

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

    International Nuclear Information System (INIS)

    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)

  13. 40 CFR 80.1155 - What are the additional requirements for a producer of cellulosic biomass ethanol or waste...

    Science.gov (United States)

    2010-07-01

    ..., 40 CFR part 32, or the Debarment, Suspension and Ineligibility provisions of the Federal Acquisition Regulations, 48 CFR, part 9, subpart 9.4, shall be deemed noncompliance with the requirements of this section... for a producer of cellulosic biomass ethanol or waste derived ethanol? 80.1155 Section...

  14. Insights into engineering of cellulosic ethanol%纤维素乙醇工程化探讨

    Institute of Scientific and Technical Information of China (English)

    岳国君; 武国庆; 林鑫

    2014-01-01

    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.%出于对能源安全、大气污染的担忧以及促进农村经济发展的考虑,世界许多国家使用乙醇作为含氧添加剂或交通运输燃料来替代汽油.纤维素乙醇生产原料丰富,且具有明显的低碳排放特性而备受关注.随着全球范围内几套大型纤维素乙醇示范装置的相继试车,工程化问题将得到解决,并有望在2015-2016年完成装置的经济性考核,逐步进入商业化阶段.为避免原料“与人争粮,与粮争地”,1代燃料乙醇将逐步向2代纤维素乙醇过渡.本文在综述近期国内外纤维素乙醇产业化概况的基础上,从化学工程和生物工程的角度对预处理、酶制剂及酶解工艺、戊糖/己糖共发酵

  15. Preliminary analysis of cellulose-based ethanol production: pathways and challenges in the Rio Grande do Sul alcohol production

    OpenAIRE

    André Luiz Fialho Blos; Tania Nunes da Silva; Angélica Margarete Magalhães; Roselene de Queiroz Chaves; Omar Inacio Santos Benedetti

    2009-01-01

    The production of ethanol in Brazil has contributed towards the replacement of fossil fuels over the past few years. Among those initiatives, the production of ethanol from cellulose is one of the areas drawing the interest of different research centers in developed countries. Hence, the production of ethanol opens up new perspectives for Brazilian states. In light of this backdrop, this paper aims at characterizing and understanding the state of the art in different technological courses and...

  16. 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

  17. Monitoring of the cellulosic ethanol fermentation process by near-infrared spectroscopy.

    Science.gov (United States)

    Pinto, Ariane S S; Pereira, Sandra C; Ribeiro, Marcelo P A; Farinas, Cristiane S

    2016-03-01

    Rapid, efficient, and low-cost technologies for monitoring the fermentation process during second generation (2G) or cellulosic ethanol production are essential for the successful implementation of this process at the commercial scale. Here, the use of near-infrared (NIR) spectroscopy associated with partial least squares (PLS) regression was investigated as a tool for monitoring the production of 2G ethanol from lignocellulosic sugarcane residues including bagasse, straw, and tops. The spectral data was based on a set of 103 alcoholic fermentation samples. Models based on different pre-processing techniques were evaluated. The best root mean square error of prediction (RMSEP) values obtained in the external validation were around 3.02 g/L for ethanol and 6.60 g/L for glucose. The findings showed that the PLS-NIR methodology was efficient in accurately predicting the glucose and ethanol concentrations during the production of 2G ethanol, demonstrating potential for use in monitoring and control of large-scale industrial processes. PMID:26748047

  18. Conversion of cellulosic feedstocks to ethanol and other chemicals using TVA's dilute sulfuric acid hydrolysis process

    International Nuclear Information System (INIS)

    The Tennessee Valley Authority (TVA) has been involved in the conversion of cellulosic feedstocks to ethanol and other products for over 10 years. Laboratory- and bench-scale research has been conducted to develop a two-stage, dilute sulfuric acid hydrolysis process. The process, based on work previously conducted at the Forest Products Laboratory, Madison, Wisconsin, uses high temperatures and pressures and short retention times to convert the hemicellulose and cellulose in biomass to fermentable sugars. Using hardwoods as the primary feedstock, evaluations of the process have resulted in sugar yields equivalent to 60 gallons of ethanol per ton of feedstock. Based on the results of bench-scale work, a two-ton-per-day pilot plant has been constructed and operated to further develop the process. Hydrolysis yields from the pilot-scale facility have been comparable to those achieved in the laboratory. Preliminary estimates have been prepared to determine capital and production costs for a 10-million-gallon-per-year ethanol-from-hardwoods facility. The effect of coproducts such as furfural, acetic acid, and carbon dioxide on production costs was also examined. This paper presents the results of bench- and pilot-scale research along with preliminary economics of TVA's dilute sulfuric acid hydrolysis process

  19. Cellulosic Ethanol Production from Saccharomyces cerevisiae Engineered for Anaerobic Conversion of Pretreated Lignocellulosic Sugars to Ethanol

    Science.gov (United States)

    Advanced high-throughput screening has resulted in the discovery of several yeast strains that are capable of anaerobically utilizing pentose, as well as hexose sugars. The growth and ethanol production of these developed strains will be described. The paradigm for using genetically engineered Sac...

  20. Preliminary analysis of cellulose-based ethanol production: pathways and challenges in the Rio Grande do Sul alcohol production

    Directory of Open Access Journals (Sweden)

    André Luiz Fialho Blos

    2009-08-01

    Full Text Available The production of ethanol in Brazil has contributed towards the replacement of fossil fuels over the past few years. Among those initiatives, the production of ethanol from cellulose is one of the areas drawing the interest of different research centers in developed countries. Hence, the production of ethanol opens up new perspectives for Brazilian states. In light of this backdrop, this paper aims at characterizing and understanding the state of the art in different technological courses and production configuration alternatives present in different parts of the world regarding cellulose-based ethanol production. To that end, research was conducted at the lumber and industrial companies connected to cellulose-based ethanol production. In other parts of the globe, the ability of planned forests to provide energy is promising, given the positive energy balance and the increase in carbon dioxide sequestering, paramount in times of global warming. The association with other crops may become a source of productive diversity for small farmers residing in degraded areas or those presenting low economic dynamism. There is the need to develop new research efforts and look more deeply into the environmental issues involved, as well as further assessment on the economic and social viability of such projects.Key-words: cellulosic ethanol, biorefinery, biomass, agrienergy, bioenergy.

  1. A pilot plant scale reactor/separator for ethanol from cellulosics. ERIP/DOE quarterly report no. 3 and 4

    Energy Technology Data Exchange (ETDEWEB)

    Dale, M.C.; Moelhman, M.; Butters, R.

    1998-12-01

    The objective of this project is to develop and demonstrate a continuous, low energy process for the conversion of cellulosics to ethanol. This process involves a pretreatment step followed by enzymatic release of sugars and the consecutive simultaneous saccharification/fermentation (SSF) of cellulose (glucans) followed by hemi-cellulose (pentosans) in a multi-stage continuous stirred reactor separator (CSRS). During quarters 3 and 4, we have completed a literature survey on cellulase production, activated one strain of Trichoderma reesei. We continued developing our proprietary Steep Delignification (SD) process for biomass pretreatment. Some problems with fermentations were traces to bad cellulase enzyme. Using commercial cellulase enzymes from Solvay & Genecor, SSF experiments with wheat straw showed 41 g/L ethanol and free xylose of 20 g/L after completion of the fermentation. From corn stover, we noted 36 g/L ethanol production from the cellulose fraction of the biomass, and 4 g/L free xylose at the completion of the SSF. We also began some work with paper mill sludge as a cellulose source, and in some preliminary experiments obtained 23 g/L ethanol during SSF of the sludge. During year 2, a 130 L process scale unit will be operated to demonstrate the process using straw or cornstalks. Co-sponsors of this project include the Indiana Biomass Grants Program, Bio-Process Innovation.

  2. Develop and Demonstrate the Cellulose to Ethanol Process: Executive Summary of the Final Technical Report, 17 September 1980 - 17 March 1982

    Energy Technology Data Exchange (ETDEWEB)

    Emert, George H.; Becker, Dana K.; Bevernitz, Kurt J.; Gracheck, Stephen J.; Kienholz, Eldon W.; Rivers, Dougals B.; Zoldak, Bernadette R.; Woodford, Lindley C.

    1982-01-01

    The Biomass Research Center at the University of Arkansas was contracted by the Solar Energy Research Institute to 'Develop and Demonstrate the Cellulose to Ethanol Process.' The purpose of the contract was to accelerate site selection, site specific engineering, and research and development leading to the determination of the feasibility of economically operating a cellulose to ethanol commercial scale plant.

  3. 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 techni......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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Derr, Dan

    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.

  5. Characterization, Genetic Variation, and Combining Ability of Maize Traits Relevant to the Production of Cellulosic Ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, A. J.; Coors, J. G.; de Leon, N.; Wolfrum, E. J.; Hames, B. R.; Sluiter, A. D.; Weimer, P. J.

    2009-01-01

    Maize (Zea mays L.) stover has been identified as an important feedstock for the production of cellulosic ethanol. Our objectives were to measure hybrid effect and combining ability patterns of traits related to cellulosic ethanol production, determine if germplasm and mutations used for silage production would also be beneficial for feedstock production, and examine relationships between traits that are relevant to selective breeding. We evaluated grain hybrids, germplasm bred for silage production, brown-midrib hybrids, and a leafy hybrid. Yield and composition traits were measured in four environments. There was a 53% difference in stover yield between commercial grain hybrids that were equivalent for other production-related traits. Silage germplasm may be useful for increasing stover yield and reducing lignin concentration. We found much more variation among hybrids than either in vitro ruminal fermentability or polysaccharide concentration. Correlations between traits were mostly favorable or nonexistent. Our results suggest that utilizing standing genetic variation of maize in breeding programs could substantially increase the amount of biofuels produced from stover per unit area of land.

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

    International Nuclear Information System (INIS)

    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)

  7. Heterogeneous Catalysis of C–O Bond Cleavage for Cellulose Deconstruction: A Potential Pathway for Ethanol Production

    OpenAIRE

    Crews, Kristy; Reeves, Crystal; Thomas, Porsha; Abugri, Daniel; Russell, Albert; Michael L. Curry

    2014-01-01

    Due to difficulty deconstructing the linkages between lignin, hemicellulose and cellulose during the conversion of cellulose to sugar, the commercial production of cellulosic ethanol is limited. This can be overcome by using a high surface-area metal catalyst. In this study, high surface-area metal NPs were synthesized using 20 mM of chloroplatinic acid and cobalt chloride prepared in THF with 0.1 mM of generation four poly(amido)amine (PAMAM) terminated dendrimer (G4-NH2) prepared in methano...

  8. Cellulosic ethanol production using a yeast consortium displaying a minicellulosome and β-glucosidase

    Directory of Open Access Journals (Sweden)

    Kim Sujin

    2013-02-01

    Full Text Available Abstract Background Cellulosic biomass is considered as a promising alternative to fossil fuels, but its recalcitrant nature and high cost of cellulase are the major obstacles to utilize this material. Consolidated bioprocessing (CBP, combining cellulase production, saccharification, and fermentation into one step, has been proposed as the most efficient way to reduce the production cost of cellulosic bioethanol. In this study, we developed a cellulolytic yeast consortium for CBP, based on the surface display of cellulosome structure, mimicking the cellulolytic bacterium, Clostridium thermocellum. Results We designed a cellulolytic yeast consortium composed of four different yeast strains capable of either displaying a scaffoldin (mini CipA containing three cohesin domains derived from C. thermocellum, or secreting one of the three types of cellulases, C. thermocellum CelA (endoglucanase containing its own dockerin, Trichoderma reesei CBHII (exoglucanase fused with an exogenous dockerin from C. thermocellum, or Aspergillus aculeatus BGLI (β-glucosidase. The secreted dockerin-containing enzymes, CelA and CBHI, were randomly assembled to the surface-displayed mini CipA via cohesin-dockerin interactions. On the other hand, BGLI was independently assembled to the cell surface since we newly found that it already has a cell adhesion characteristic. We optimized the cellulosome activity and ethanol production by controlling the combination ratio among the four yeast strains. A mixture of cells with the optimized mini CipA:CelA:CBHII:BGLI ratio of 2:3:3:0.53 produced 1.80 g/l ethanol after 94 h, indicating about 20% increase compared with a consortium composed of an equal amount of each cell type (1.48 g/l. Conclusions We produced cellulosic ethanol using a cellulolytic yeast consortium, which is composed of cells displaying mini cellulosomes generated via random assembly of CelA and CBHII to a mini CipA, and cells displaying BGLI independently. One

  9. 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.

  10. 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.

  11. Effect of Yeast Extract and Vitamin B12 on Ethanol Production from Cellulose by Clostridium thermocellum I-1-B

    OpenAIRE

    Sato, Kanji; Goto, Shingo; Yonemura, Sotaro; Sekine, Kenji; Okuma, Emiko; Takagi, Yoshio; Hon-Nami, Koyu; Saiki, Takashi

    1992-01-01

    Addition to media of yeast extract, a vitamin mixture containing vitamin B12, biotin, pyridoxamine, and p-aminobenzoic acid, or vitamin B12 alone enhanced formation of ethanol but decreased lactate production in the fermentation of cellulose by Clostridium thermocellum I-1-B. A similar effect was not observed with C. thermocellum ATCC 27405 and JW20.

  12. Progress of cellulose ethanol research & development%纤维素乙醇研究开发进展

    Institute of Scientific and Technical Information of China (English)

    胡徐腾

    2011-01-01

    Cellulose ethanol has become a priority of research with a bright future. It may become one of the most important renewable energy sources in the future. Cellulose ethanol research &development is reviewed, and the development history and the latest worldwide progress of cellulose ethanol research & development are summarized. The difficulties and problems in current cellulose ethanol commercialization are analyzed. The directions of research & development are presented.%纤维素乙醇是当今的研究热点,具有广阔的发展前景,将成为未来最重要的可再生能源之一.本文介绍了纤维素乙醇的研发概况,综述了国内外研究开发历程与最新进展,分析了目前纤维素乙醇燃料产业化存在的困难和问题,指出了当前和今后的研发方向.

  13. Cellulose

    Science.gov (United States)

    Cellulose properties and structure are reviewed, with a primary focus on crystal structure and polymorphy. This focus highlights the conversion from cellulose I to cellulose II, which converts the molecules to being all parallel to each other in the crystal to being antiparallel. This has been co...

  14. Production of cellulosic ethanol from sugarcane bagasse by steam explosion: Effect of extractives content, acid catalysis and different fermentation technologies.

    Science.gov (United States)

    Neves, P V; Pitarelo, A P; Ramos, L P

    2016-05-01

    The production of cellulosic ethanol was carried out using samples of native (NCB) and ethanol-extracted (EECB) sugarcane bagasse. Autohydrolysis (AH) exhibited the best glucose recovery from both samples, compared to the use of both H3PO4 and H2SO4 catalysis at the same pretreatment time and temperature. All water-insoluble steam-exploded materials (SEB-WI) resulted in high glucose yields by enzymatic hydrolysis. SHF (separate hydrolysis and fermentation) gave ethanol yields higher than those obtained by SSF (simultaneous hydrolysis and fermentation) and pSSF (pre-hydrolysis followed by SSF). For instance, AH gave 25, 18 and 16gL(-1) of ethanol by SHF, SSF and pSSF, respectively. However, when the total processing time was taken into account, pSSF provided the best overall ethanol volumetric productivity of 0.58gL(-1)h(-1). Also, the removal of ethanol-extractable materials from cane bagasse had no influence on the cellulosic ethanol production of SEB-WI, regardless of the fermentation strategy used for conversion. PMID:26943936

  15. Catalytic conversion of sugarcane bagasse to cellulosic ethanol: TiO2 coupled nanocellulose as an effective hydrolysis enhancer.

    Science.gov (United States)

    Jabasingh, S Anuradha; Lalith, D; Prabhu, M Arun; Yimam, Abubekker; Zewdu, Taye

    2016-01-20

    The present study deals with the production of cellulosic ethanol from bagasse using the synthesized TiO2 coupled nanocellulose (NC-TiO2) as catalyst. Aspergillus nidulans AJSU04 cellulase was used for the hydrolysis of bagasse. NC-TiO2 at various concentrations was added to bagasse in order to enhance the yield of reducing sugars. Complex interaction between cellulase, bagasse, NC-TiO2 and the reaction environment is thoroughly studied. A mathematical model was developed to describe the hydrolysis reaction. Ethanol production from enzymatically hydrolyzed sugarcane bagasse catalyzed with NC-TiO2 was carried out using Saccharomyces cerevisiae ATCC 20602. The glucose release rates and ethanol concentrations were determined. Ethanol produced was found to be strongly dependent on pretreatment given, hydrolysis and fermentation conditions. The study confirmed the promising accessibility of NC-TiO2, for enhanced glucose production rates and improved ethanol yield. PMID:26572403

  16. 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.

  17. Combination of enzymatic hydrolysis and ethanol organosolv pretreatments: effect on lignin structures, delignification yields and cellulose-to-glucose conversion.

    Science.gov (United States)

    Obama, Patrick; Ricochon, Guillaume; Muniglia, Lionel; Brosse, Nicolas

    2012-05-01

    Enzymatic pre-hydrolysis using the industrial enzymatic cocktail Cellulyve® was assessed as a first step in a pretreatment process of Miscanthus biomass involving an aqueous-ethanol organosolv treatment. (13)C and (31)P Nuclear Magnetic Resonance and size exclusion chromatography were used to analyze the cellulose and lignin before and after treatment. It was demonstrated that despite a very low impact on the fibre structure (observed by Scanning Electron Microscopy) and composition (in terms of sugars and polyphenolics content), the enzymatic pre-treatment disrupted the lignocellulosic matrix to a considerable extend. This weakening permitted enhanced removal of lignin during organosolv pulping and increased hydrolysability of the residual cellulosic pulp for the production of monomeric glucose. Using this combined treatment, a delignification yield of 93% and an enzymatic cellulose-to-glucose conversion of 75% were obtained. PMID:22424922

  18. A new beta-glucosidase producing yeast for lower-cost cellulosic ethanol production from xylose-extracted corncob residues by simultaneous saccharification and fermentation

    Science.gov (United States)

    Conventional cellulose-to-ethanol conversion by simultaneous saccharification and fermentation (SSF)requires enzymatic saccharification using both cellulase and ß-glucosidase allowing cellulose utilization by common ethanologenic yeast. Here we report a new yeast strain of Clavispora NRRL Y-50464 th...

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  1. Crystalline structure and morphological properties of porous cellulose/clay composites: The effect of water and ethanol as coagulants.

    Science.gov (United States)

    Ahmadzadeh, Safoura; Desobry, Stephane; Keramat, Javad; Nasirpour, Ali

    2016-05-01

    In this study, cellulose foams incorporated with surface-modified montmorillonite (SM-MMT) were prepared following NaOH dissolution and regeneration into water and ethanol. According to the SEM images, the type of coagulating agent significantly affected the morphological properties of composite foams. The crystalline parameters were evaluated using wide-angle X-ray diffraction (WAXD), which showed an increase in crystal size as the effect of SM-MMT; however, the crystal size decreased for the samples treated with ethanol. The distribution of hydrogen bond types was also investigated using Fourier transform infrared (FTIR). Resolving the hydrogen-bonded OH stretching band at around 3340 into five bands indicated that presence of SM-MMT caused the shift of OH-stretching vibration band to lower wave number due to new hydrogen bonds between cellulose and SM-MMT. In general, the results indicated a change in the contents of the intra- and inter-molecular hydrogen bonds when the coagulant was changed or SM-MMT was incorporated. PMID:26877015

  2. 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. PMID:20419480

  3. Application in the Ethanol Fermentation of Immobilized Yeast Cells in Matrix of Alginate/Magnetic Nanoparticles, on Chitosan-Magnetite Microparticles and Cellulose-coated Magnetic Nanoparticles

    CERN Document Server

    Ivanova, Viara; Hristov, Jordan

    2011-01-01

    Saccharomyces cerevisiae cells were entrapped in matrix of alginate and magnetic nanoparticles and covalently immobilized on magnetite-containing chitosan and cellulose-coated magnetic nanoparticles. Cellulose-coated magnetic nanoparticles with covalently immobilized thermostable {\\alpha}-amylase and chitosan particles with immobilized glucoamylase were also prepared. The immobilized cells and enzymes were applied in column reactors - 1/for simultaneous corn starch saccharification with the immobilized glucoamylase and production of ethanol with the entrapped or covalently immobilized yeast cells, 2/ for separate ethanol fermentation of the starch hydrolysates with the fixed yeasts. Hydrolysis of corn starch with the immobilized {\\alpha}-amylase and glucoamylase, and separate hydrolysis with the immobilized {\\alpha}-amylase were also examined. In the first reactor the ethanol yield reached approx. 91% of the theoretical; the yield was approx. 86% in the second. The ethanol fermentation was affected by the typ...

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

    OpenAIRE

    Juliana Q. Albarelli; Adriano V. Ensinas; Silva, Maria 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...

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

    OpenAIRE

    Shah Nilay; Bauen Ausilio; Slade Raphael

    2009-01-01

    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 p...

  6. Sustainable Production of Crop Residue as a Cellulosic Ethanol Feedstock: REAP – Renewable Energy Assessment Project

    Science.gov (United States)

    Domestic ethanol production is a strategy for reducing dependence on imported energy and release of greenhouse gases from use of fossil-energy-derived motor vehicle fuel. Federal and state governments are encouraging the use of ethanol. Initially energy crops, such as switchgrass, willow, and poplar...

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

    International Nuclear Information System (INIS)

    Highlights: • Biorefinery concept for simultaneous recovery of cellulose and phenolic compounds. • Sono-assisted organosolv/H2O2 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

  8. Economic evaluation of United States ethanol production from ligno-cellulosic feedstocks

    Science.gov (United States)

    Choi, Youn-Sang

    This paper evaluates the economic feasibility and economy-wide impacts of the U. S. ethanol production from lignocellulosic feedstocks (LCF) using Tennessee Valley Authority's (TVA's) dilute acid hydrolysis process. A nonlinear mathematical programming model of a single ethanol producer, whose objective is profit maximization, is developed. Because of differences in their chemical composition and production process, lignocellulosic feedstocks are divided into two groups: Biomass feedstocks, which refer to crop residues, energy crops and woody biomass, and municipal solid waste (MSW). Biomass feedstocks are more productive and less costly in producing ethanol and co-products, while MSW generates an additional income to the producer from a tipping fee and recycling. The analysis suggests that, regardless of types of feedstocks used, TVA's conversion process can enhance the economic viability of ethanol production as long as furfural is produced from the hemicellulose fraction of feedstocks as a co-product. The high price of furfural makes it a major factor in determining the economic feasibility of ethanol production. Along with evaluating economic feasibility of LCF-to-ethanol production, the optimal size of a plant producing ethanol using TVA's conversion process is estimated. The larger plant would have the advantage of economies of scale, but also have a disadvantage of increased collection and transportation costs for bulky biomass from more distant locations. We assume that the plant is located in the state of Missouri and utilizes only feedstocks produced in the state. The results indicate that the size of a plant using Biomass feedstocks is much bigger than one using MSW. The difference of plant sizes results from plant location and feedstock availability. One interesting finding is that energy crops are not feasible feedstocks for LCF-to-ethanol production due to their high price. Next, a static CGE model is developed to estimate the U.S. economy

  9. Cellulosic ethanol production via consolidated bioprocessing at 75 °C by engineered Caldicellulosiruptor bescii

    OpenAIRE

    Chung, Daehwan; Cha, Minseok; Snyder, Elise N.; Elkins, James G.; Guss, Adam M.; Westpheling, Janet

    2015-01-01

    Background The C. bescii genome does not encode an acetaldehyde/alcohol dehydrogenase or an acetaldehyde dehydrogenase and no ethanol production is detected in this strain. The recent introduction of an NADH-dependent AdhE from C. thermocellum (Fig. 1a) in an ldh mutant of this strain resulted in production of ethanol from un-pretreated switchgrass, but the thermolability of the C. thermocellum AdhE at the optimum growth temperature of C. bescii (78 °C) meant that ethanol was not produced abo...

  10. Cellulosic Ethanol Production from Xylose-extracted Corncob Residue by SSF Using Inhibitor- and Thermal-tolerant Yeast Clavispora NRRL Y-50339

    Science.gov (United States)

    Xylose-extracted corncob residue, a byproduct of the xylose-producing industry using corncobs, is an abundant potential energy resource for cellulosic ethanol production. Simultaneous saccharification and fermentation (SSF) is considered an ideal one-step process for conversion of lignocellulosic b...

  11. 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.

  12. 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%.

  13. 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

  14. Life Cycle Assessment of the Energy Independence and Security Act of 2007: Ethanol - Global Warming Potential and Environmental Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Heath, G. A.; Hsu, D. D.; Inman, D.; Aden, A.; Mann, M. K.

    2009-07-01

    The objective of this study is to use life cycle assessment (LCA) to evaluate the global warming potential (GWP), water use, and net energy value (NEV) associated with the EISA-mandated 16 bgy cellulosic biofuels target, which is assumed in this study to be met by cellulosic-based ethanol, and the EISA-mandated 15 bgy conventional corn ethanol target. Specifically, this study compares, on a per-kilometer-driven basis, the GWP, water use, and NEV for the year 2022 for several biomass feedstocks.

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

    International Nuclear Information System (INIS)

    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 CO2 eq.), acidification potential (AP = 355.34 kg SO2 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 CO2 eq. was recorded for the whole biorefinery

  16. 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.

  17. The Perspectives for Genetically Modified Cellulosic Ethanol in the Czech Republic

    OpenAIRE

    Blahova, Pavla; Janda, Karel; Kristoufek, Ladislav

    2014-01-01

    This paper connects the biofuels literature with genetic modifications literature by considering the potential of genetic modifications for increasing the efficiency of cellulosic biofuels production. This is done for one particular case through analyzing the effect of genetically modified corn adoption on overall yields of corn for silage. Our econometric model confirms that the use of genetically modified corn with inserted MON810 gene increases the overall corn biomass yield in the product...

  18. PRINCIPLES AND ECONOMICS OF PRETREATING CELLULOSE IN WATER FOR ETHANOL PRODUCTION

    Science.gov (United States)

    The aqueous pretreatment of corn fiber and corn stover at a pH controlled to minimize the hydrolysis of oligosaccharides and formation of monosaccharides during pretreatment has been studied at the laboratory scale, and in the case of corn fiber, in an operational ethanol plant. For corn fiber, the...

  19. Comparative Study of SPORL and Dilute Acid Pretreatments of Spruce for Cellulosic Ethanol Production

    Science.gov (United States)

    The performance of two pretreatment methods, Sulfite Pretreatment to Overcome Recalcitrance of Lignocellulose (SPORL) and Dilute Acid (DA), was compared in pretreating softwood (spruce) for fuel ethanol production under the same conditions of temperature (180°C), time (30 min), sulfuric acid loading...

  20. Security of feedstocks supply for future bio-ethanol production in Thailand

    International Nuclear Information System (INIS)

    This study assesses the security of feedstock supply to satisfy the increased demand for bio-ethanol production based on the recent 15 years biofuels development plan and target (year 2008-2022) of the Thai government. Future bio-ethanol systems are modeled and the feedstock supply potentials analyzed based on three scenarios including low-, moderate- and high-yields improvement. The three scenarios are modeled and key dimensions including availability; diversity; and environmental acceptability of feedstocks supply in terms of GHG reduction are evaluated through indicators such as net feedstock balances, Shannon index and net life cycle GHG emissions. The results show that only the case of high yields improvement scenario can result in a reliable and sufficient supply of feedstocks to satisfy the long-term demands for bio-ethanol and other related industries. Cassava is identified as the critical feedstock and a reduction in cassava export is necessary. The study concludes that to enhance long-term security of feedstocks supply for sustainable bio-ethanol production in Thailand, increasing use of sugarcane juice as feedstock, improved yields of existing feedstocks and promoting production of bio-ethanol derived from agricultural residues are three key recommendations that need to be urgently implemented by the policy makers. (author)

  1. Security of feedstocks supply for future bio-ethanol production in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Silalertruksa, Thapat; Gheewala, Shabbir H. [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 126 Prachauthit Road, Bangkok 10140 (Thailand)

    2010-11-15

    This study assesses the security of feedstock supply to satisfy the increased demand for bio-ethanol production based on the recent 15 years biofuels development plan and target (year 2008-2022) of the Thai government. Future bio-ethanol systems are modeled and the feedstock supply potentials analyzed based on three scenarios including low-, moderate- and high-yields improvement. The three scenarios are modeled and key dimensions including availability; diversity; and environmental acceptability of feedstocks supply in terms of GHG reduction are evaluated through indicators such as net feedstock balances, Shannon index and net life cycle GHG emissions. The results show that only the case of high yields improvement scenario can result in a reliable and sufficient supply of feedstocks to satisfy the long-term demands for bio-ethanol and other related industries. Cassava is identified as the critical feedstock and a reduction in cassava export is necessary. The study concludes that to enhance long-term security of feedstocks supply for sustainable bio-ethanol production in Thailand, increasing use of sugarcane juice as feedstock, improved yields of existing feedstocks and promoting production of bio-ethanol derived from agricultural residues are three key recommendations that need to be urgently implemented by the policy makers. (author)

  2. Security of feedstocks supply for future bio-ethanol production in Thailand

    International Nuclear Information System (INIS)

    This study assesses the security of feedstock supply to satisfy the increased demand for bio-ethanol production based on the recent 15 years biofuels development plan and target (year 2008-2022) of the Thai government. Future bio-ethanol systems are modeled and the feedstock supply potentials analyzed based on three scenarios including low-, moderate- and high-yields improvement. The three scenarios are modeled and key dimensions including availability; diversity; and environmental acceptability of feedstocks supply in terms of GHG reduction are evaluated through indicators such as net feedstock balances, Shannon index and net life cycle GHG emissions. The results show that only the case of high yields improvement scenario can result in a reliable and sufficient supply of feedstocks to satisfy the long-term demands for bio-ethanol and other related industries. Cassava is identified as the critical feedstock and a reduction in cassava export is necessary. The study concludes that to enhance long-term security of feedstocks supply for sustainable bio-ethanol production in Thailand, increasing use of sugarcane juice as feedstock, improved yields of existing feedstocks and promoting production of bio-ethanol derived from agricultural residues are three key recommendations that need to be urgently implemented by the policy makers. - Research highlights: →Bioethanol in Thailand derived from molasses, cassava, sugarcane juice could yield reductions of 64%, 49% and 87% in GHGs when compared to conventional gasoline. →High yields improvement are required for a reliable and sufficient supply of molasses, cassava and sugarcane to satisfy the long-term demands for bio-ethanol and other related industries. →Other factors to enhance long-term security of feedstocks supply for sustainable bioethanol production in Thailand include increasing use of sugarcane juice as feedstock and promoting production of bioethanol derived from agricultural residues.

  3. A new β-glucosidase producing yeast for lower-cost cellulosic ethanol production from xylose-extracted corncob residues by simultaneous saccharification and fermentation.

    Science.gov (United States)

    Liu, Z Lewis; Weber, Scott A; Cotta, Michael A; Li, Shi-Zhong

    2012-01-01

    This study reports a new yeast strain of Clavispora NRRL Y-50464 that is able to utilize cellobiose as sole source of carbon and produce sufficient native β-glucosidase enzyme activity for cellulosic ethanol production using SSF. In addition, this yeast is tolerant to the major inhibitors derived from lignocellulosic biomass pre-treatment such as 2-furaldehyde (furfural) and 5-(hydroxymethyl)-2-furaldehyde (HMF), and converted furfural into furan methanol in less than 12h and HMF into furan-2,5-dimethanol within 24h in the presence of 15 mM each of furfural and HMF. Using xylose-extracted corncob residue as cellulosic feedstock, an ethanol production of 23 g/l was obtained using 25% solids loading at 37 °C by SSF without addition of exogenous β-glucosidase. Development of this yeast aids renewable biofuels development efforts for economic consolidated SSF bio-processing. PMID:22133603

  4. A pilot plant scale reactor/separator for ethanol from cellulosics. Quarterly report No. 1 & 2, October 1, 1997--March 30, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Dale, M.C.

    1998-06-01

    The basic objective of this project is to develop and demonstrate a continuous, low energy process for the conversion of cellulosics to ethanol. This process involves a pretreatment step followed by enzymatic release of sugars and the consecutive saccharification/fermentation of cellulose (glucans) followed by hemi-cellulose (glucans) in a multi-stage continuous stirred reactor separator (CSRS). During year 1, pretreatment and bench scale fermentation trials will be performed to demonstrate and develop the process, and during year 2, a 130 L or larger process scale unit will be operated to demonstrate the process using straw or cornstalks. Co-sponsors of this project include the Indiana Biomass Grants Program, Bio-Process Innovation, Xylan Inc as a possible provider of pretreated biomass.

  5. 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.

  6. 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. PMID:27155264

  7. 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.

  8. 中国纤维素乙醇技术的研究进展%Advancing Cellulosic Ethanol Technology in China

    Institute of Scientific and Technical Information of China (English)

    杨斌; Charles; E.; Wyman

    2007-01-01

    中国面临着严重的能源短缺和环境污染问题,中国政府正在局部几个省份内政策性鼓励燃料乙醇生产和使用.尽管当前主要是用玉米和谷物作为生产乙醇的原料,然而中国具有大量潜在的低成本的纤维素生物质原料,可以极大地扩大乙醇的产量,降低原料成本.近20年来,由于技术的革命性进步,已使得纤维素乙醇的生产成本从4美元/加仑以上,降低至约1.2-1.5美元/加仑.其中,每吨生物质约44美元.因此,目前乙醇掺汽油具有十分强的市场竞争力.已有几个公司正在建造首批商业纤维素乙醇工厂,虽然这些刚起步的小型设施在合理利用和管理上风险较小,但规模经济需要较大型工厂.尽管配送生物质原料的成本会随需求的增加而增加,但在乙醇生产基础上的生物精炼技术的发展,尤其是化工产品和动力的协同生产,将会使全过程的经济可行性大大提高.进一步深入的基础研究,将解决低成本下实现纤维素的完全利用,以确保在无政策性补贴的前提下,真正使纤维素乙醇成为具有市场竞争力的低成本纯液体燃料.%China now faces very serious energy shortages and environmental pollution problems. Thus, the Chinese government is encouraging ethanol use as an alternative transportation fuel by introducing fuel ethanol production and distribution within several provinces. Although the current emphasis is on ethanol production from corn and other grains,China has huge quantities of low cost cellulosic biomass that could significantly expand ethanol production volume and reduce feedstock costs. Over the last 20 years, a number of technical advances have dropped the cost of making cellulosic ethanol from more than $4.00/gallon to only about $1.20-1.50/gallon for biomass costing about $44 per ton. At this cost, ethanol is competitive for blending with gasoline, and several companies are working to build the first commercial

  9. Synthesis and Characterization of Carboxymethyl Cellulose (CMC) from Water Hyacinth Using Ethanol-Isobutyl Alcohol Mixture as the Solvents

    OpenAIRE

    Asep Handaya Saputra; Linnisa Qadhayna; Alia Badra Pitaloka

    2014-01-01

    Water hyacinth, a free-floating aquatic weed originating from South America has become a major floating weed of tropical and subtropical regions of the world. The plant has the tendency to regenerate from seeds and fragment allowing rapid increase in plant population. Water hyacinth is however a fiber that is rich in its cellulosic compounds, which can be derivated into somewhat multifunctional properties. Carboxymethyl Cellulose (CMC) is a derivated cellulose that is used in food products as...

  10. Green high-performance liquid chromatography enantioseparation of lansoprazole using a cellulose-based chiral stationary phase under ethanol/water mode.

    Science.gov (United States)

    Ferretti, Rosella; Zanitti, Leo; Casulli, Adriano; Cirilli, Roberto

    2016-04-01

    A simple and environmentally friendly reversed-phase high-performance liquid chromatography method for the separation of the enantiomers of lansoprazole has been developed. The chromatographic resolution was carried out on the cellulose-based Chiralpak IC-3 chiral stationary phase using a green and low-toxicity ethanol-aqueous mode. The effects of water content in the mobile phase and column temperature on the retention of the enantiomers of lansoprazole and its chiral and achiral related substances have been carefully investigated. A mixed-mode hydrophilic interaction liquid chromatography and reversed-phase retention mechanism operating on the IC-3 chiral stationary phase allowed us to achieve simultaneous enantioselective and chemoselective separations in water-rich conditions. The enantiomers of lansoprazole were baseline resolved with a mobile phase consisting of ethanol/water 50:50 without any interference coming from chiral and achiral impurities within 10 min. PMID:26910378

  11. Well-to-wheels energy use and greenhouse gas emissions of ethanol from corn, sugarcane and cellulosic biomass for US use

    Science.gov (United States)

    Wang, Michael; Han, Jeongwoo; Dunn, Jennifer B.; Cai, Hao; Elgowainy, Amgad

    2012-12-01

    Globally, bioethanol is the largest volume biofuel used in the transportation sector, with corn-based ethanol production occurring mostly in the US and sugarcane-based ethanol production occurring mostly in Brazil. Advances in technology and the resulting improved productivity in corn and sugarcane farming and ethanol conversion, together with biofuel policies, have contributed to the significant expansion of ethanol production in the past 20 years. These improvements have increased the energy and greenhouse gas (GHG) benefits of using bioethanol as opposed to using petroleum gasoline. This article presents results from our most recently updated simulations of energy use and GHG emissions that result from using bioethanol made from several feedstocks. The results were generated with the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model. In particular, based on a consistent and systematic model platform, we estimate life-cycle energy consumption and GHG emissions from using ethanol produced from five feedstocks: corn, sugarcane, corn stover, switchgrass and miscanthus. We quantitatively address the impacts of a few critical factors that affect life-cycle GHG emissions from bioethanol. Even when the highly debated land use change GHG emissions are included, changing from corn to sugarcane and then to cellulosic biomass helps to significantly increase the reductions in energy use and GHG emissions from using bioethanol. Relative to petroleum gasoline, ethanol from corn, sugarcane, corn stover, switchgrass and miscanthus can reduce life-cycle GHG emissions by 19-48%, 40-62%, 90-103%, 77-97% and 101-115%, respectively. Similar trends have been found with regard to fossil energy benefits for the five bioethanol pathways.

  12. Well-to-wheels energy use and greenhouse gas emissions of ethanol from corn, sugarcane and cellulosic biomass for US use

    International Nuclear Information System (INIS)

    Globally, bioethanol is the largest volume biofuel used in the transportation sector, with corn-based ethanol production occurring mostly in the US and sugarcane-based ethanol production occurring mostly in Brazil. Advances in technology and the resulting improved productivity in corn and sugarcane farming and ethanol conversion, together with biofuel policies, have contributed to the significant expansion of ethanol production in the past 20 years. These improvements have increased the energy and greenhouse gas (GHG) benefits of using bioethanol as opposed to using petroleum gasoline. This article presents results from our most recently updated simulations of energy use and GHG emissions that result from using bioethanol made from several feedstocks. The results were generated with the GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation) model. In particular, based on a consistent and systematic model platform, we estimate life-cycle energy consumption and GHG emissions from using ethanol produced from five feedstocks: corn, sugarcane, corn stover, switchgrass and miscanthus. We quantitatively address the impacts of a few critical factors that affect life-cycle GHG emissions from bioethanol. Even when the highly debated land use change GHG emissions are included, changing from corn to sugarcane and then to cellulosic biomass helps to significantly increase the reductions in energy use and GHG emissions from using bioethanol. Relative to petroleum gasoline, ethanol from corn, sugarcane, corn stover, switchgrass and miscanthus can reduce life-cycle GHG emissions by 19–48%, 40–62%, 90–103%, 77–97% and 101–115%, respectively. Similar trends have been found with regard to fossil energy benefits for the five bioethanol pathways. (letter)

  13. 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.

  14. 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. PMID:25351629

  15. Produção conjunta de fibras celulósicas e etanol a partir do bambu Combined production of cellulosic fibers and ethanol from bamboo culm

    Directory of Open Access Journals (Sweden)

    Anisio Azzini

    1987-01-01

    Full Text Available No presente estudo com Bambusa vulgaris Schrad., procurou-se desenvolver um novo processo de utilização do bambu, visando à produção conjunta de etanol e fibras celulósicas para papel. Os rendimentos em fibras celulósicas e etanol foram obtidos em função da idade do colmo (1, 3 e 5 anos e região de amostragem em cada colmo (base, meio e ponta. Esses rendimentos, bem como outros relacionados com a fração fibrosa, glicose e amido, foram determinados com solução diluída de ácido sulfúrico. A densidade básica dos colmos foi determinada em cavacos antes do seu tratamento. Pelos resultados obtidos, é tecnicamente possível a produção conjunta de etanol e fibras celulósicas a partir do bambu. Os rendimentos em fibras celulósicas (46,85 a 56,04% e etanol (12,77 a 14,79 litros/100 kg de cavacos foram mais elevados nas regiões mediana e ponta dos colmos mais velhos. Essa mesma tendência foi observada para a glicose (teores de 22,80 a 26,41% e amido hidrolisado (18,99 a 24,27%. O rendimento em fibras brutas ou fração fibrosa (69,35 a 76,35% foi mais elevado nos cavacos provenientes dos colmos mais novos. A densidade básica dos cavacos não variou em função da idade do colmo (0,573 a 0,628 g/cm³, mas em função da região de amostragem (0,518 a 0,683 g/cm³, sendo mais densos os cavacos das regiões mediana e ponta dos colmos.In this study with Bambusa vulgaris Schrad, a new process of bamboo utilization was established to produce cellulosic fibers for papermaking and ethanol. The yields of ethanol and cellulosic fibers were determined in function of culm age (1, 3 and 5 years and portion of sampling in each culm (base, middle and top. The yields of cellulosic fibers, ethanol and compounds like glucose and starch were determined in shreddered chips after treatment with diluted sulphuric acid solution. The combined production of ethanol and cellulosic fibers was feasible technically. The yields of cellulosic fibers varied from

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

    International Nuclear Information System (INIS)

    Use of ethanol as a transportation fuel in the United States has grown from 76 dam3 in 1980 to over 40.1 hm3 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.

  17. Glucose, stem dry weight variation, principal component and cluster analysis for some agronomic traits among 16 regenerated Crotalaria juncea accessions for potential cellulosic ethanol.

    Science.gov (United States)

    Morris, J Bradley; Antonious, George F

    2013-01-01

    The objectives of this research were to identify candidate sunn hemp accessions having high concentrations of cellulose for use as parents in breeding for cellulose and to determine variability for glucose content and some important agronomic traits among sunn hemp accessions. Since sunn hemp is an under-utilized species, glucose content and agronomic trait variation is essential for the identification of superior sunn hemp accessions for use as potential ethanol for biofuel. Sixteen sunn hemp accessions including the following plant introductions (expressed as glucose concentration) and stem dry weights were studied. "Sixteen sunn hemp accessions including the following plant introductions (expressed as glucose concentration) and stem dry weights were studied." In addition, to verify variability, these traits plus morphological, phenological, and seed reproductive traits were analyzed using multivariate and cluster analysis. The accessions, PI 250487, PI 337080, and PI 219717 produced the highest glucose concentrations (859, 809, and 770 mg g(-1) stem dry weight, respectively), however PI 468956 produced the highest stem dry weight (258 g). Branching significantly correlated with foliage (r(2) = 0.67**) and relative maturity (r(2) = 0.60*), while maturity had a significantly negative correlation with seed number (r(2) = -0.67**) and plant width (r(2) = -0.53*) as well. Seed number significantly correlated with plant width (r(2) = 0.57*). Average linkage cluster analysis grouped the 16 sunn hemp accessions into well-defined phenotypes with four distinct seed-producing groups and one outlier. Based on multivariate and cluster analysis, sufficient variation among these16 sunn hemp accessions exists to support the development of cellulosic ethanol producing cultivars with improved architecture, early maturity, seed yield, glucose concentrations, and stem dry weights. PMID:23356343

  18. 亚临界乙醇条件下的纤维素热化学液化研究%THE INVESTIGATION OF CELLULOSE LIQUEFICATION IN SUBCRITICAL ETHANOL

    Institute of Scientific and Technical Information of China (English)

    戴伟娣; 许玉; 李静; 徐俊明

    2012-01-01

    Iiquefication of cellulose in subcritical ethanol using acid catalyst had been studied. It was found that sulfuric acid could provide efficient catalytic performance. Under the optimum conditions for Iiquefication of mass ratio of cellulose, sulfuric acid, glycerol and ethanol = 1:0. 025: 2. 5: 5 , reaction temperature of 250 °C , reaction time lh, the conversion of cellulose was up to 95. 7%. The physical-chemical properties had been studied. The viscosity of hydrolytic product was 509. 3mmVs, the acid number was 2. 51mgK0H/g and hydroxyl number was 784. 6mgK0H/g. The liquefied product was characterized by IR, GC-MS, !H NMR. The results show the liquefied product has abundant hydroxy radicals, which could be used to make rigid polyurethane foam. The mechanism for cellulose was also discussed.%以甘油为液化促进剂,在酸性催化剂条件下对微晶纤维素的亚临界液化工艺进行考察.实验结果表明:浓硫酸是较好的酸性催化剂,在微晶纤维素、浓硫酸、甘油和乙醇的质量比为1∶0.025∶2.5∶5,反应温度250℃,反应时间1h的条件下,转化率可达95.7%.对液化产物的理化性能进行分析,粘度509.3mm2/s、酸值2.51 mgKOH/g和羟值784.6mgKOH/g.通过红外光谱(IR)、GC-MS、1H NMR等技术手段对产物进行分析表征.结果表明,产物含有丰富的羟基基团,粘度适宜,适用于聚氨酯发泡体系.对液化机理进行探讨.

  19. Opportunity for profitable investments in cellulosic biofuels

    International Nuclear Information System (INIS)

    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. - Research highlights: → The likelihood of a significant cellulosic ethanol industry in the US looks dim. → Drop-in biofuels made from cellulosic feedstocks have a more promising future. → The spatial dimension of markets for cellulosic feedstocks will be limited. → Corn ethanol will be a tough competitor for cellulosic ethanol.

  20. 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)

  1. 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

  2. Managing Multiple Mandates: A System of Systems Model to Analyze Strategies for Producing Cellulosic Ethanol and Reducing Riverine Nitrate Loads in the Upper Mississippi River Basin.

    Science.gov (United States)

    Housh, Mashor; Yaeger, Mary A; Cai, Ximing; McIsaac, Gregory F; Khanna, Madhu; Sivapalan, Murugesu; Ouyang, Yanfeng; Al-Qadi, Imad; Jain, Atul K

    2015-10-01

    Implementing public policies often involves navigating an array of choices that have economic and environmental consequences that are difficult to quantify due to the complexity of multiple system interactions. Implementing the mandate for cellulosic biofuel production in the Renewable Fuel Standard (RFS) and reducing hypoxia in the northern Gulf of Mexico by reducing riverine nitrate-N loads represent two such cases that overlap in the Mississippi River Basin. To quantify the consequences of these interactions, a system of systems (SoS) model was developed that incorporates interdependencies among the various subsystems, including biofuel refineries, transportation, agriculture, water resources and crop/ethanol markets. The model allows examination of the impact of imposing riverine nitrate-N load limits on the biofuel production system as a whole, including land use change and infrastructure needs. The synergies of crop choice (first versus second generation biofuel crops), infrastructure development, and environmental impacts (streamflow and nitrate-N load) were analyzed to determine the complementarities and trade-offs between environmental protection and biofuel development objectives. For example, the results show that meeting the cellulosic biofuel target in the RFS using Miscanthus x giganteus reduces system profits by 8% and reduces nitrate-N loads by 12% compared to the scenario without a mandate. However, greater water consumption by Miscanthus is likely to reduce streamflow with potentially adverse environmental consequences that need to be considered in future decision making. PMID:26348783

  3. Effects of the pretreatment method on high solids enzymatic hydrolysis and ethanol fermentation of the cellulosic fraction of sugarcane bagasse.

    Science.gov (United States)

    Martins, Luiza Helena da Silva; Rabelo, Sarita Cândida; da Costa, Aline Carvalho

    2015-09-01

    This work evaluated ethanol production from sugarcane bagasse at high solids loadings in the pretreatment (20-40% w/v) and hydrolysis (10-20% w/v) stages. The best conditions for diluted sulfuric acid, AHP and Ox-B pretreatments were determined and mass balances including pretreatment, hydrolysis and fermentation were calculated. From a technical point of view, the best pretreatment was AHP, which enabled the production of glucose concentrations near 8% with high productivity (3.27 g/Lh), as well as ethanol production from 100.9 to 135.4 kg ethanol/ton raw bagasse. However, reagent consumption for acid pretreatment was much lower. Furthermore, for processes that use pentoses and hexoses separately, this pretreatment produces the most desirable pentoses liquor, with higher xylose concentration in the monomeric form. PMID:26004382

  4. Air quality impacts of increased use of ethanol under the United States’ Energy Independence and Security Act

    Science.gov (United States)

    Cook, Rich; Phillips, Sharon; Houyoux, Marc; Dolwick, Pat; Mason, Rich; Yanca, Catherine; Zawacki, Margaret; Davidson, Ken; Michaels, Harvey; Harvey, Craig; Somers, Joseph; Luecken, Deborah

    2011-12-01

    Increased use of ethanol in the United States fuel supply will impact emissions and ambient concentrations of greenhouse gases, "criteria" pollutants for which the U. S. EPA sets ambient air quality standards, and a variety of air toxic compounds. This paper focuses on impacts of increased ethanol use on ozone and air toxics under a potential implementation scenario resulting from mandates in the U. S. Energy Independence and Security Act (EISA) of 2007. The assessment of impacts was done for calendar year 2022, when 36 billion gallons of renewable fuels must be used. Impacts were assessed relative to a baseline which assumed ethanol volumes mandated by the first renewable fuels standard promulgated by U. S. EPA in early 2007. This assessment addresses both impacts of increased ethanol use on vehicle and other engine emissions, referred to as "downstream" emissions, and "upstream" impacts, i.e., those connected with fuel production and distribution. Air quality modeling was performed for the continental United States using the Community Multi-scale Air Quality Model (CMAQ), version 4.7. Pollutants included in the assessment were ozone, acetaldehyde, ethanol, formaldehyde, acrolein, benzene, and 1,3-butadiene. Results suggest that increased ethanol use due to EISA in 2022 will adversely increase ozone concentrations over much of the U.S., by as much as 1 ppb. However, EISA is projected to improve ozone air quality in a few highly-populated areas that currently have poor air quality. Most of the ozone improvements are due to our assumption of increases in nitrogen oxides (NO x) in volatile organic compound (VOC)-limited areas. While there are some localized impacts, the EISA renewable fuel standards have relatively little impact on national average ambient concentrations of most air toxics, although ethanol concentrations increase substantially. Significant uncertainties are associated with all results, due to limitations in available data. These uncertainties are

  5. 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.

  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. Construction Cost Sensitivity of a Lignocellulosic Ethanol Biorefinery

    OpenAIRE

    Busby, David P.; Philips, Andrew L.; Herndon, Cary W., Jr.

    2008-01-01

    The technology has been developed to convert feedstock with cellulose content into ethanol. However, ethanol produced from cellulosic feedstock is the same as ethanol distilled from grain. The objective of research is to determine the price per gallon of ethanol needed so that producing lignocellulosic based ethanol become economically feasible.

  8. Fuel Ethanol Production from Pretreated Wheat Straw Using a Recombinant Bacterium

    Science.gov (United States)

    In 2008, about 9 billion gallons of ethanol were produced from corn starch in the U.S. The Energy Independence and Security Act of 2007 requires that 36 billion gallons of renewable fuel be produced in 2022 of which cellulosic biofuel is to contribute 16 billion gallons. Currently, there is no com...

  9. 木薯纤维素乙醇发酵的纤维素酶成本评价%Evaluation of the cellulase cost during the cassava cellulose ethanol fermentation process

    Institute of Scientific and Technical Information of China (English)

    方镇宏; 邓红波; 张小希; 张建; 鲍杰

    2013-01-01

    木薯中的纤维素成分约占木薯干重的10%(W/W).文中以木薯燃料乙醇生产的木薯纤维素酒渣为原料,从纤维素酶成本角度评估了三种利用木薯纤维素组分发酵生产乙醇的方法,包括木薯纤维素酒渣的直接糖化和乙醇发酵、木薯纤维素酒渣预处理后的糖化与乙醇发酵、木薯乙醇发酵中同步淀粉与纤维素糖化以及乙醇发酵.结果表明,前两种方法的纤维素利用效率不高,酶成本分别达到13602、11659元/吨乙醇.第三种方法,即在木薯乙醇发酵过程同时加入糖化酶和纤维素酶,进行同步淀粉与纤维素糖化,进而进行乙醇发酵,木薯纤维素乙醇的收益最高.发酵结束时的乙醇浓度从101.5g/L提高到107.0g/L,纤维素酶成本为3 589元/吨乙醇.此方法利用木薯纤维素与木薯淀粉同时进行,不会带来额外的设备及操作投入,酶成本低于产品乙醇价格,可实现盈利,因此第三种方法为木薯纤维用于乙醇发酵的最适方法,本研究结果将为木薯乙醇产业深度利用木薯纤维提供依据.%Cellulose takes nearly 10% (W/W) dry weight of cassava tubers. In this study, the cellulase cost of different ethanol fermentation from cassava cellulose was evaluated. The processes include the direct saccharification and fermentation of original cassava cellulose residues, the direct saccharification and fermentation of pretreated cassava cellulose residues, and the simultaneous co-saccharification and fermentation of cassava starch and cassava cellulose. The results show that the cassava cellulose utilization in the first two processes were low with the enzyme cost of 13 602 and 11 659 RMB Yuan per tone of ethanol, respectively. In the third process, the final ethanol concentration increased from 101.5 g/L to 107.0 g/L when cassava cellulose and cassava starch were saccharified simultaneously. Comparing to the first two processes, the third one demonstrated the lowest enzyme cost at 3

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

    International Nuclear Information System (INIS)

    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)

  11. Production of the Anaerobic GMAX-L Yeast Using High-Throughput Mating and Transformation of Saccharomyces cerevisiae With Identified Genes For Simultaneous Cellulosic Ethanol and Biodiesel Production

    Science.gov (United States)

    Tailored GMAX-L yeast engineering for strains capable of universal ethanol production industrially with coproduction of an expressed lipase catalyst for coproduction of ethyl esters from corn oil and ethanol from the modern dry grind ethanol facility: Production of the stable baseline glucose, mann...

  12. Thermophilic degradation of cellulosic biomass

    Science.gov (United States)

    Ng, T.; Zeikus, J. G.

    1982-12-01

    The conversion of cellulosic biomass to chemical feedstocks and fuel by microbial fermentation is an important objective of developing biotechnology. Direct fermentation of cellulosic derivatives to ethanol by thermophilic bacteria offers a promising approach to this goal. Fermentations at elevated temperatures lowers the energy demand for cooling and also facilitates the recovery of volatile products. In addition, thermophilic microorganisms possess enzymes with greater stability than those from mesophilic microorganisms. Three anaerobic thermophilic cocultures that ferment cellulosic substrate mainly to ethanol have been described: Clostridium thermocellum/Clostriidium thermohydrosulfuricum, C. thermocellum/Clostridium thermosaccharolyticum, and C. thermocellum/Thermoanaerobacter ethanolicus sp. nov. The growth characteristics and metabolic features of these cocultures are reviewed.

  13. 纤维素乙醇的原料预处理方法及工艺流程研究进展%Feedstock pretreatment and technological process of cellulose ethanol production

    Institute of Scientific and Technical Information of China (English)

    杨娟; 滕虎; 刘海军; 徐友海; 吕继萍; 王继艳

    2013-01-01

    木质纤维生物质是储量丰富且最有前景的生产燃料乙醇的可再生生物质资源,利用木质纤维生物质生产乙醇主要包括以下步骤:原料预处理、发酵以及产物分离纯化,其中,原料的预处理工艺是限制纤维素乙醇产业化的一个技术瓶颈.本文对酸法、碱法、蒸汽爆破法、合成气法等7种典型预处理方法进行了介绍并对其工艺流程进行简要的说明,同时对不同的预处理方法的优劣、适用范围和工艺流程转化效率等进行了对比,以期为纤维素乙醇预处理方法的工艺选择和评价提供一些参考.提出了纤维素乙醇的产业化前景:不同预处理技术的合理结合使用会有效提高转化率;较好的过程设计能够降低成本,有利于整个过程的经济性.%Lignocellulose is a promising resource for bioethanol production due to its abundance, renewablility, and low cost. Ethanol production from lignocellulose biomass comprises the following critical steps: feedstock pretreatment, sugar fermentation, separation and purification of the ethanol, among which pretreatment step is identified as technological bottleneck for commercialization of cellulosic ethanol technology. The characteristics and technological processes of typical pretreatment methods are reviewed, such as acid pretreatment, alkali pretreatment, steam explosion, syngas etc., and the advantages and disadvantages, available materials and process efficiency of those methods are compared and discussed to provide guidance for the selection and evaluation of pretreatment process in cellulose ethanol production. Finally, the prospect of commercialization of fuel ethanol production from cellulosic biomass is presented. Reasonable integration of different pretreatment technologies will effectively improve the conversion rate. A preferable process design can help in reducing cost, contributing to the economy of the whole process.

  14. Bioconversion of cellulose. Work progress for FY 1980

    Science.gov (United States)

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

    1981-03-01

    Progress is reported on the following: kinetic and mechanistic studies on cellulose enzymes, yeast nutrition, models of yeast growth and ethanol inhibition, by product inhibition in cell recycle and vacuum fermentation, hollow fiber reactor, thermodynamics of ethanol water systems, novel ethanol water separations, and simultaneous and sequential cellulose fermenting organisms.

  15. Comparative study on processes of simultaneous saccharification and fermentation with high solid concentration for cellulosic ethanol production%高底物浓度纤维乙醇同步糖化发酵工艺的比较

    Institute of Scientific and Technical Information of China (English)

    常春; 王铎; 王林风; 马晓建

    2012-01-01

    The effects of various simultaneous saccharification fermentation (SSF) technologies on ethanol yield from cellulose were investigated. Using steam-exploded corn stalks as raw materials, five SSF technologies, including traditional SSF, SSF combined with preliminary enzymatic hydrolysis, fed-batch SSF coupled with preliminary enzymatic hydrolysis, SSF united with preliminary enzymatic hydrolysis coupling with vacuum separation and fed-batch SSF associated with preliminary enzymatic hydrolysis coupling with vacuum separation, were used for decomposition of the stalks. By comparing the fermentation process with higher solid concentration including 15% (mass) and 30% (mass), it was found that the fed-batch SSF combined with preliminary enzymatic hydrolysis is an effective way for raising substrate concentration. However, higher substrate concentration may lead to decrease of final ethanol yield. Moreover, SSF coupled with vacuum separation can weaken the product inhibition, and increase the ethanol yield. The ethanol productivity by the fed-batch SSF associated with preliminary enzymatic hydrolysis coupling with vacuum separation is 0. 40 g · L-1 · h-1, the highest value obtained, indicating that this technology can be a potential new technology.

  16. Analysis on chemical components changes in preparation process of cellulosic ethanol from poplar wood%杨木制备纤维乙醇过程中化学成分变化的分析

    Institute of Scientific and Technical Information of China (English)

    闫兴伟; 崔琳; 张林; 王芳; 陈茜文

    2015-01-01

    杨树是我国重要的速生树种。以杨木为原料制备生物乙醇是解决当今能源问题的一项新的尝试。对杨木原料蒸汽爆破预处理后以及菌处理后的化学成分及化学性质进行了测定分析。通过对比其化学成分(纤维素、木素、半纤维素、抽出物、灰分及蛋白质)的变化,研究了以杨木为原料制备生物乙醇生产过程中化学成分变化机理,旨在为指导杨木制备木质纤维乙醇的生产,并为发酵后副产物的回收再利用提供理论依据。%Poplar is an important fast-growing species in China. The preparation of bio-ethanol with poplar wood as the raw material is a new attempt to solve today’s energy problems. After steam-exploded pretreatment and then bacteria treatment to the poplar wood raw materials, the materials’ chemical composition and properties were measured and analyzed. Through contrasting the changes of the materials’ chemical composition(cellulose, lignin, hemicelluloses, extracts, ash and protein), the mechanism of chemical change of the tested materials in the bioethanol production process prepared from poplar wood was studied, the surplus product contained 64.07%lignin, 6.78% cellulose and 6.88% hemicellulose. The results provide a theoretical basis for guiding the preparation of poplar wood cellulosic ethanol production, and the subsequent recycling of fermentation by-products.

  17. FRACTIONATION OF LIGNOCELLULOSIC BIOMASS FOR FUEL-GRADE ETHANOL PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    F.D. Guffey; R.C. Wingerson

    2002-10-01

    PureVision Technology, Inc. (PureVision) of Fort Lupton, Colorado is developing a process for the conversion of lignocellulosic biomass into fuel-grade ethanol and specialty chemicals in order to enhance national energy security, rural economies, and environmental quality. Lignocellulosic-containing plants are those types of biomass that include wood, agricultural residues, and paper wastes. Lignocellulose is composed of the biopolymers cellulose, hemicellulose, and lignin. Cellulose, a polymer of glucose, is the component in lignocellulose that has potential for the production of fuel-grade ethanol by direct fermentation of the glucose. However, enzymatic hydrolysis of lignocellulose and raw cellulose into glucose is hindered by the presence of lignin. The cellulase enzyme, which hydrolyzes cellulose to glucose, becomes irreversibly bound to lignin. This requires using the enzyme in reagent quantities rather than in catalytic concentration. The extensive use of this enzyme is expensive and adversely affects the economics of ethanol production. PureVision has approached this problem by developing a biomass fractionator to pretreat the lignocellulose to yield a highly pure cellulose fraction. The biomass fractionator is based on sequentially treating the biomass with hot water, hot alkaline solutions, and polishing the cellulose fraction with a wet alkaline oxidation step. In September 2001 PureVision and Western Research Institute (WRI) initiated a jointly sponsored research project with the U.S. Department of Energy (DOE) to evaluate their pretreatment technology, develop an understanding of the chemistry, and provide the data required to design and fabricate a one- to two-ton/day pilot-scale unit. The efforts during the first year of this program completed the design, fabrication, and shakedown of a bench-scale reactor system and evaluated the fractionation of corn stover. The results from the evaluation of corn stover have shown that water hydrolysis prior to

  18. 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 ...

  19. 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...

  20. GMAX Yeast Background Strain Made from Industrial Tolerant Saccharomyces Cerevisiae Engineered to Convert Pretreated Lignocellulosic Starch and Cellulosic Sugars Universally to Ethanol Anaerobically

    Science.gov (United States)

    Tailored GMAX yeast background strain technology for universal ethanol production industrially: Production of the stable baseline glucose, mannose, arabinose, xylose-utilizing (GMAX) yeast will be evaluated by taking the genes identified in high-throughput screening for a plasmid-based yeast to util...

  1. Continuous Cellulosic Bioethanol Fermentation by Cyclic Fed-Batch Cocultivation

    OpenAIRE

    Jiang, He-Long; He, Qiang; He, Zhili; Hemme, Christopher L.; Wu, Liyou; Zhou, Jizhong

    2013-01-01

    Cocultivation of cellulolytic and saccharolytic microbial populations is a promising strategy to improve bioethanol production from the fermentation of recalcitrant cellulosic materials. Earlier studies have demonstrated the effectiveness of cocultivation in enhancing ethanolic fermentation of cellulose in batch fermentation. To further enhance process efficiency, a semicontinuous cyclic fed-batch fermentor configuration was evaluated for its potential in enhancing the efficiency of cellulose...

  2. 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 b

  3. 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

  4. Achieving the Security, Environmental, and Economic Potential of Bioenergy. Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Riggs, John A

    2006-06-07

    A group of business, government, environmental and academic leaders convened in a dialogue by the Aspen Institute proposed a series of actions to promote the widespread commercialization of both corn and cellulosic ethanol to improve energy security, the environment, and the economy. Co-chaired by Booz Allen Hamilton Vice President and former CIA Director R. James Woolsey and former Congressman Tom Ewing (R. IL), they developed a series of recommendations involving improved crop yields, processing of biomass into ethanol, manufacture of more cars that can burn either ethanol or gasoline, and the provision of ethanol pumps at more filling stations. Their report, "A High Growth Strategy for Ethanol, includes a discussion of the potential of ethanol, the group's recommendations, and a series of discussion papers commissioned for the dialogue.

  5. 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.

  6. ACCESSIBILITY AND CRYSTALLINITY OF CELLULOSE

    Directory of Open Access Journals (Sweden)

    Michael Ioelovich

    2009-08-01

    Full Text Available The accessibility of cellulose samples having various degrees of crystallinity was studied with respect to molecules of water, lower primary alcohols, and lower organic acids. It was found that small water molecules have full access to non-crystalline domains of cellulose (accessibility coefficient α = 1. Molecules of the lowest polar organic liquids (methanol, ethanol, and formic acid have partial access into the non-crystalline domains (α<1, and with increasing diameter of the organic molecules their accessibility to cellulose structure decreases. Accessibility of cellulose samples to molecules of various substances is a linear function of the coefficient α and the content of non-crystalline domains. The relationship between crystallinity (X and accessibility (A of cellulose to molecules of some liquids has been established as A = α (1-X. The water molecules were found to have greater access to cellulose samples than the molecules of the investigated organic liquids. The obtained results permit use of accessibility data to estimate the crystallinity of cellulose, to examine the structural state of non-crystalline domains, and to predict the reactivity of cellulose samples toward some reagents.

  7. Engineering of a novel cellulose-adherent cellulolytic Saccharomyces cerevisiae for cellulosic biofuel production.

    Science.gov (United States)

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

    2016-01-01

    Cellulosic biofuel is the subject of increasing attention. The main obstacle toward its economic feasibility is the recalcitrance of lignocellulose requiring large amount of enzyme to break. Several engineered yeast strains have been developed with cellulolytic activities to reduce the need for enzyme addition, but exhibiting limited effect. Here, we report the successful engineering of a cellulose-adherent Saccharomyces cerevisiae displaying four different synergistic cellulases on the cell surface. The cellulase-displaying yeast strain exhibited clear cell-to-cellulose adhesion and a "tearing" cellulose degradation pattern; the adhesion ability correlated with enhanced surface area and roughness of the target cellulose fibers, resulting in higher hydrolysis efficiency. The engineered yeast directly produced ethanol from rice straw despite a more than 40% decrease in the required enzyme dosage for high-density fermentation. Thus, improved cell-to-cellulose interactions provided a novel strategy for increasing cellulose hydrolysis, suggesting a mechanism for promoting the feasibility of cellulosic biofuel production. PMID:27079382

  8. Ethanol production from paper sludge using Kluyveromyces marxianus

    International Nuclear Information System (INIS)

    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.

  9. Comparing the fermentation performance of Escherichia coli KO11, Saccharomyces cerevisiae 424A(LNH-ST) and Zymomonas mobilis AX101 for cellulosic ethanol production

    OpenAIRE

    Dale Bruce E; Balan Venkatesh; Gunawan Christa; Lau Ming W

    2010-01-01

    Abstract Background Fermentations using Escherichia coli KO11, Saccharomyces cerevisiae 424A(LNH-ST), and Zymomonas mobilis AX101 are compared side-by-side on corn steep liquor (CSL) media and the water extract and enzymatic hydrolysate from ammonia fiber expansion (AFEX)-pretreated corn stover. Results The three ethanologens are able produce ethanol from a CSL-supplemented co-fermentation at a metabolic yield, final concentration and rate greater than 0.42 g/g consumed sugars, 40 g/L and 0.7...

  10. Ethanol production in China: Potential and technologies

    International Nuclear Information System (INIS)

    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)

  11. A techno-economic evaluation of the effects of centralized cellulosic ethanol and co-products refinery options with sugarcane mill clustering

    International Nuclear Information System (INIS)

    This work compares the calculated techno-economic performance for thermochemical and biochemical conversion of sugarcane residues, considering future conversion plants adjacent to sugarcane mills in Brazil. Process models developed by the National Renewable Energy Laboratory were adapted to reflect the Brazilian feedstock composition and used to estimate the cost and performance of these two conversion technologies. Models assumed that surplus bagasse from the mill would be used as the feedstock for conversion, while cane trash collected from the field would be used as supplementary fuel at the mill. The integration of the conversion technology to the mill enabled an additional ethanol production of 0.033 m3 per tonne of cane for the biochemical process and 0.025 m3 t-1 of cane plus 0.004 m3 t-1 of cane of higher alcohols for the thermochemical process. For both cases, electricity is an important co-product for the biorefinery, but especially for biochemical conversion, with surpluses of about 50 kWh t-1 of cane. The economic performance of the two technologies is quite similar in terms of the minimum ethanol selling price (MESP), at 318 $ m-3 (United States 2007 dollars) for biochemical conversion and 329 $ m-3 for thermochemical conversion. (author)

  12. Air Quality Impacts of Increased Use of Ethanol under the United States' Energy Independence and Security Act

    Science.gov (United States)

    Increased use of ethanol in the United States fuel supply will impact emissions and ambient concentrations of greenhouse gases, “criteria” pollutants for which the U. S. EPA sets ambient air quality standards, and a variety of air toxic compounds. This paper focuses on impacts of...

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

    Science.gov (United States)

    Guzzo de Carli Poelking, Viviane; Giordano, Andrea; Ricci-Silva, Maria Esther; Rhys Williams, Thomas Christopher; Alves Peçanha, Diego; Contin Ventrella, Marília; Rencoret, Jorge; Ralph, John; Pereira Barbosa, Márcio Henrique; Loureiro, Marcelo

    2015-01-01

    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. PMID:26252208

  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. Method and apparatus for treating a cellulosic feedstock

    Science.gov (United States)

    Nguyen, Quang A.; Burke, Murray J.; Hillier, Sunalie N.

    2015-09-08

    Methods and apparatus for treating, pre-treating, preparing and conveying a cellulosic feedstock, such as for ethanol production, are disclosed. More specifically, the invention relates to methods and apparatus for treating a cellulosic feedstock by mixing and heating the cellulosic feedstock and/or by moistening and heating the cellulosic feedstock. The invention also relates to a holding tank, and a method of utilizing the holding tank whereby bridging may be reduced or eliminated and may result in a product stream from autohydrolysis or hydrolysis having an improved yield. The invention further relates to methods and apparatus for obtaining and conveying a cellulosic feedstock, which may be used for the subsequent production of a fermentable sugar stream from the cellulose and hemicellulose in the cellulosic feedstock wherein the fermentable sugar stream may be used for subsequent ethanol production. The invention also relates to a method and apparatus for withdrawing one or more feedstock stream from a holding tank.

  16. Ethanol from biomass - The quest for efficiency

    Science.gov (United States)

    Deyoung, H. G.

    1982-02-01

    Methods for the production of ethanol to be used as an energy source from readily renewable biomass, natural materials based largely on cellulose, are reviewed. Current procedures for ethanol production utilize energy-inefficient processes and costly materials, such as corn, and thus are highly impractical for the large-scale ethanol production which is envisioned as a partial solution for US energy needs. The use of cellulosic raw materials is at the center of present research efforts, but no reliable and high-yielding conversion technique has yet been demonstrated. Methods of ethanol production are discussed and attention is focused on new fermentation technologies which potentially could overcome the problems associated with the use of cellulosic raw materials. For example, a strain of yeast is being developed which has the capability to convert up to twice as much of our agricultural wastes to ethanol than was thought possible just a year ago

  17. Comparing the fermentation performance of Escherichia coli KO11, Saccharomyces cerevisiae 424A(LNH-ST and Zymomonas mobilis AX101 for cellulosic ethanol production

    Directory of Open Access Journals (Sweden)

    Dale Bruce E

    2010-05-01

    Full Text Available Abstract Background Fermentations using Escherichia coli KO11, Saccharomyces cerevisiae 424A(LNH-ST, and Zymomonas mobilis AX101 are compared side-by-side on corn steep liquor (CSL media and the water extract and enzymatic hydrolysate from ammonia fiber expansion (AFEX-pretreated corn stover. Results The three ethanologens are able produce ethanol from a CSL-supplemented co-fermentation at a metabolic yield, final concentration and rate greater than 0.42 g/g consumed sugars, 40 g/L and 0.7 g/L/h (0-48 h, respectively. Xylose-only fermentation of the tested ethanologenic bacteria are five to eight times faster than 424A(LNH-ST in the CSL fermentation. All tested strains grow and co-ferment sugars at 15% w/v solids loading equivalent of ammonia fiber explosion (AFEX-pretreated corn stover water extract. However, both KO11 and 424A(LNH-ST exhibit higher growth robustness than AX101. In 18% w/w solids loading lignocellulosic hydrolysate from AFEX pretreatment, complete glucose fermentations can be achieved at a rate greater than 0.77 g/L/h. In contrast to results from fermentation in CSL, S. cerevisiae 424A(LNH-ST consumed xylose at the greatest extent and rate in the hydrolysate compared to the bacteria tested. Conclusions Our results confirm that glucose fermentations among the tested strains are effective even at high solids loading (18% by weight. However, xylose consumption in the lignocellulosic hydrolysate is the major bottleneck affecting overall yield, titer or rate of the process. In comparison, Saccharomyces cerevisiae 424A(LNH-ST is the most relevant strains for industrial production for its ability to ferment both glucose and xylose from undetoxified and unsupplemented hydrolysate from AFEX-pretreated corn stover at high yield.

  18. Cellulose is not just cellulose

    DEFF Research Database (Denmark)

    Hidayat, Budi Juliman; Felby, Claus; Johansen, Katja S.;

    2012-01-01

    Most secondary plant cell walls contain irregular regions known as dislocations or slip planes. Under industrial biorefining conditions dislocations have recently been shown to play a key role during the initial phase of the enzymatic hydrolysis of cellulose in plant cell walls. In this review we...... 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...

  19. Ethanol production from modern biorefinery: Robotic platform for production of Saccharomyces cerevisiae engineered to convert pretreated lignocellulosic sugars to ethanol anaerobically

    Science.gov (United States)

    Biorefineries to produce ethanol are becoming abundant but the future of ethanol requires that cellulosic ethanol paradigms are researched. A discussion of the existing ethanol production and biorefinery capacity will be made. The USDA, ARS, NCAUR, BBC group has developed a robotic platform to scr...

  20. Extraction and characterization of enzymatic hydrolysis lignin from cellulosic ethanol fermentation residue%纤维乙醇发酵残渣中酶解木质素的提取与表征

    Institute of Scientific and Technical Information of China (English)

    潘奇; 陈介南; 张新民; 詹鹏; 张林

    2015-01-01

    The resource of the wastes from cellulosic ethanol production gets more and more attention. Enzymatic hydrolysis lignin (EHL) was extracted and characterized from the residue of bioethanol fermentation using enzymatic poplar fiber. The single factor experiment analysis was conducted to study the effect of alkali concentration , solid-liquid ratio , reaction temperature and time on extraction of EHL. Reaction conditions were optimized by orthogonal analysis. The structure of EHL was characterized using ultraviolet (UV),Fourier Transform-Infrared Spectroscopy (FT-IR). The optimum EHL extraction conditions were NaOH 40g/L , solid-liquid ratio 1∶30 , reaction temperature 60℃ and reaction time 2.5h. UV and FT-IR spectra showed that the EHL retained intact lignin structure,mainly with syringyl lignin,holding high chemical activities.%近年来,将纤维素乙醇生产过程中所产生的废物进行资源化利用已越来越受重视。本研究利用杨木纤维酶解发酵产纤维素乙醇的残渣进行木质素的提取与表征,采用单因素试验分析碱浓度、料液比、反应温度、反应时间对酶解木质素提取效果的影响,并对反应条件进行正交优化,应用UV、FT-IR光谱仪对分离出的酶解木质素结构进行表征。结果表明:酶解木质素最佳的提取工艺条件为NaOH浓度40g/L、料液比1∶30、反应温度60℃、反应时间2.5h。紫外和红外光谱显示酶解木质素保留了完好的木质素结构,以紫丁香基木质素为主,有良好的化学活性。

  1. Security

    Science.gov (United States)

    Technology & Learning, 2008

    2008-01-01

    Anytime, anywhere, learning provides opportunities to create digital learning environments for new teaching styles and personalized learning. As part of making sure the program is effective, the safety and security of students and assets are essential--and mandated by law. The Children's Internet Protection Act (CIPA) addresses Internet content…

  2. Which biofuel market does the ethanol tariff protect? Implications for social welfare and GHG emissions

    OpenAIRE

    Crago, Christine Lasco; Khanna, Madhu

    2011-01-01

    The ethanol tariff is one of the instruments used by the government to encourage domestic ethanol production. Existing literature analyzing the market and welfare effects of the US ethanol tariff has concluded that removing the tariff would increase social surplus and reduce greenhouse gas (GHG) emissions, due to the replacement of corn ethanol with lower cost and lower GHG intensive sugarcane ethanol. This paper re-examines these findings in the presence of a domestic cellulosic ethanol indu...

  3. Analysis of Enzymatic Degradation of Cellulose Microfibrils using Quantitative Surface Plasmon Resonance Imaging

    Science.gov (United States)

    Reiter, Kyle; Raegen, Adam; Allen, Scott; Quirk, Amanda; Clarke, Anthony; Lipkowski, Jacek; Dutcher, John

    2013-03-01

    Cellulose is the largest component of biomass on Earth and, as a result, is a significant potential energy source. The production of cellulosic ethanol as a fuel source requires conversion of cellulose fibers into fermentable sugars. Increasing our understanding of the action of cellulose enzymes (cellulases) on cellulose microfibrils is an important step in developing more efficient industrial processes for the production of cellulosic ethanol. We have used a custom designed Surface Plasmon Resonance imaging (SPRi) device to study the action of cellulases from the Hypocrea jecorinasecretome on bacterial cellulose microfibrils. This has allowed us to determine the rates of action and extent of degradation of cellulose microfibrils on exposure to both individual cellulases and combinations of different classes of cellulases, which has allowed us to investigate synergistic interactions between the cellulases.

  4. Preliminary study for optimization of enzymatic hydrolysis of waste cellulosic materials

    OpenAIRE

    LUMINITA GEORGESCU; IULIANA LEUŞTEAN; GABRIELA BAHRIM

    2011-01-01

    Lignocellulose is a generic term describing the main constituents in most plants, namely cellulose, hemicelluloses, and lignin. Cellulose is a glucose polysaccharide, hemicelluloses are polysaccharides with a backbone of different hexoses (glucose, mannose, galactose) and pentoses (xylan, arabinose), and lignin is a complex network of different phenyl propane units. The cellulosic materials are potential sources of ethanol. Steps of this process are saccharification of cellulose to reduce sug...

  5. Implications of increased ethanol production

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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.

  7. Continuous cellulosic bioethanol fermentation by cyclic fed-batch cocultivation.

    Science.gov (United States)

    Jiang, He-Long; He, Qiang; He, Zhili; Hemme, Christopher L; Wu, Liyou; Zhou, Jizhong

    2013-03-01

    Cocultivation of cellulolytic and saccharolytic microbial populations is a promising strategy to improve bioethanol production from the fermentation of recalcitrant cellulosic materials. Earlier studies have demonstrated the effectiveness of cocultivation in enhancing ethanolic fermentation of cellulose in batch fermentation. To further enhance process efficiency, a semicontinuous cyclic fed-batch fermentor configuration was evaluated for its potential in enhancing the efficiency of cellulose fermentation using cocultivation. Cocultures of cellulolytic Clostridium thermocellum LQRI and saccharolytic Thermoanaerobacter pseudethanolicus strain X514 were tested in the semicontinuous fermentor as a model system. Initial cellulose concentration and pH were identified as the key process parameters controlling cellulose fermentation performance in the fixed-volume cyclic fed-batch coculture system. At an initial cellulose concentration of 40 g liter(-1), the concentration of ethanol produced with pH control was 4.5-fold higher than that without pH control. It was also found that efficient cellulosic bioethanol production by cocultivation was sustained in the semicontinuous configuration, with bioethanol production reaching 474 mM in 96 h with an initial cellulose concentration of 80 g liter(-1) and pH controlled at 6.5 to 6.8. These results suggested the advantages of the cyclic fed-batch process for cellulosic bioethanol fermentation by the cocultures. PMID:23275517

  8. ETHANOL ORGANOSOLV PRETREATMENT OF BAMBOO FOR EFFICIENT ENZYMATIC SACCHARIFICATION

    OpenAIRE

    Zhiqiang Li; Benhua Fei; Zehui Jiang; Xuejun Pan,; Zhiyong Cai; Xing'e Liu,; Yan Yu

    2012-01-01

    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 t...

  9. Ethanol poisoning

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002644.htm Ethanol poisoning To use the sharing features on this page, please enable JavaScript. Ethanol poisoning is caused by drinking too much alcohol. ...

  10. Engineering of a novel cellulose-adherent cellulolytic Saccharomyces cerevisiae for cellulosic biofuel production

    Science.gov (United States)

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

    2016-01-01

    Cellulosic biofuel is the subject of increasing attention. The main obstacle toward its economic feasibility is the recalcitrance of lignocellulose requiring large amount of enzyme to break. Several engineered yeast strains have been developed with cellulolytic activities to reduce the need for enzyme addition, but exhibiting limited effect. Here, we report the successful engineering of a cellulose-adherent Saccharomyces cerevisiae displaying four different synergistic cellulases on the cell surface. The cellulase-displaying yeast strain exhibited clear cell-to-cellulose adhesion and a “tearing” cellulose degradation pattern; the adhesion ability correlated with enhanced surface area and roughness of the target cellulose fibers, resulting in higher hydrolysis efficiency. The engineered yeast directly produced ethanol from rice straw despite a more than 40% decrease in the required enzyme dosage for high-density fermentation. Thus, improved cell-to-cellulose interactions provided a novel strategy for increasing cellulose hydrolysis, suggesting a mechanism for promoting the feasibility of cellulosic biofuel production. PMID:27079382

  11. 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.

  12. Automated Yeast Transformation Protocol to Engineer S. cerevisiae Strains for Cellulosic Ethanol Production with Open Reading Frames that Express Proteins Binding to Xylose Isomerase Identified using Robotic Two-hybrid Screen

    Science.gov (United States)

    Commercialization of fuel ethanol production from lignocellulosic biomass has focused on engineering the glucose-fermenting industrial yeast Saccharomyces cerevisiae to utilize pentose sugars. Since S. cerevisiae naturally metabolizes xylulose, one approach involves introducing xylose isomerase (XI...

  13. Cellulose-Based Membranes for Solutes Fractionation

    Science.gov (United States)

    Anokhina, T. S.; Yushkin, A. A.; Volkov, V. V.; Antonov, S. V.; Volkov, A. V.

    This work was focused on investigation of industrial cellophane film as a membrane material for solvent nanofiltration. The effect of conditioning of cellophane membranes by stepwise changing of composition of ethanol-water binary mixtures (from ethanol to water and from water to ethanol) was studied. It was shown that such treatment leads to an increase of ethanol permeability more than two orders of magnitude over initial untreated film samples. Treated cellophane membranes possess the ethanol permeability coefficient comparable with the values for highly permeability glassy polymers. Investigation of cellophane swelling in water ethanol solutions allowed to conclude that during the treatment formation of porous in the film takes place due to increase of inter chain distances. Observed high ethanol permeability connected with the fact that formed porous structure remains after the replacement of water with ethanol. Also it was shown that rejection coefficients of a number of dyes (MW 350) were in good agreement with the degree of hydrophobicity/hydrophilicity and ability of the solvent to form hydrogen bonding with the solute molecules. It was demonstrated that cellulose-based membranes can be complimentary for other type of the membranes in fractionation of multi-components solutions.

  14. 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.

  15. Cellulose based conductive polymers

    OpenAIRE

    Lin, Haishu

    2015-01-01

    Conductive fibers show potential applications in different areas. In this thesis, cellulose and its derivatives, including carboxymethyl cellulose, cellulose acetate as well as methyl cellulose were used to produce fibers via wet spinning. Different conductive materials were also introduced in an attempt to obtain cellulose-derived conductive fibers. Different conductive fillers (Zelec, carbon black, conductive polymers) were evaluated. Among them, PEDOT and PPy conductive polymers showed...

  16. Soil Carbon and Nitrogen Dynamics Across the Hillslope-Riparian Interface in Adjacent Watersheds with Contrasting Cellulosic Biofuel Systems

    OpenAIRE

    Neal, Andrew Wilson

    2014-01-01

    Climate change resulting from emissions of fossil fuel combustion has sparked considerable interest in renewable energy and fuel production research, particularly energy derived from cellulosic ethanol, which is derived from biomass such as wood and grass. Cellulosic ethanol demonstrates a more promising future as a global energy source than corn-derived ethanol because it does not displace food crops, irrigation is not required, and chemical application rates are much lower than for annual c...

  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. Preliminary process engineering evaluation of ethanol production from vegetative crops

    Science.gov (United States)

    Moreira, A. R.; Linden, J. C.; Smith, D. H.; Villet, R. H.

    1982-12-01

    Vegetative crops show good potential as feedstock for ethanol production via cellulose hydrolysis and yeast fermentation. The low levels of lignin encountered in young plant tissues show an inverse relationship with the high cellulose digestibility during hydrolysis with cellulose enzymes. Ensiled sorghum species and brown midrib mutants of sorghum exhibit high glucose yields after enzyme hydrolysis as well. Vegetative crop materials as candidate feedstocks for ethanol manufacture should continue to be studied. The species studied so far are high value cash crops and result in relatively high costs for the final ethanol product. Unconventional crops, such as pigweed, kochia, and Russian thistle, which can use water efficiently and grow on relatively arid land under conditions not ideal for food production, should be carefully evaluated with regard to their cultivation requirements, photosynthesis rates, and cellulose digestibility. Such crops should result in more favorable process economics for alcohol production.

  19. 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)

  20. Can ethanol alone meet California's low carbon fuel standard? An evaluation of feedstock and conversion alternatives

    Science.gov (United States)

    Zhang, Yimin; Joshi, Satish; MacLean, Heather L.

    2010-01-01

    The feasibility of meeting California's low carbon fuel standard (LCFS) using ethanol from various feedstocks is assessed. Lifecycle greenhouse gas (GHG) emissions, direct agricultural land use, petroleum displacement directly due to ethanol blending, and production costs for a number of conventional and lignocellulosic ethanol pathways are estimated under various supply scenarios. The results indicate that after considering indirect land use effects, all sources of ethanol examined, except Midwest corn ethanol, are viable options to meet the LCFS. However, the required ethanol quantity depends on the GHG emissions performance and ethanol availability. The quantity of ethanol that can be produced from lignocellulosic biomass resources within California is insufficient to meet the year 2020 LCFS target. Utilizing lignocellulosic ethanol to meet the LCFS is more attractive than utilizing Brazilian sugarcane ethanol due to projected lower direct agricultural land use, dependence on imported energy, ethanol cost, required refueling infrastructure modifications and penetration of flexible fuel E85 vehicles. However, advances in cellulosic ethanol technology and commercial production capacity are required to support moderate- to large-scale introduction of low carbon intensity cellulosic ethanol. Current cellulosic ethanol production cost estimates suffer from relatively high uncertainty and need to be refined based on commercial scale production data when available.

  1. Ethanol fermentation

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    The inulin of chicory slices was hydrolyzed enzymically and fermented to ethanol. Maximum ethanol yield was achieved with fermentation combined with saccharification, using cellulase and inulinase for saccharification. The fermenting organism was Saccharomyces cerevisiae. Kluyveromyces fragilis, containing endogenous inulinase, was also used, but with lower yield.

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

    OpenAIRE

    Rodríguez-Zúñiga, Ursula Fabiola; Cannella, David; de Campos Giordano, Roberto; de Lima Camargo Giordano, Raquel; Jørgensen, Henning; Felby, Claus

    2015-01-01

    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 of cellulose. The applied pre-treatment methods are organosolv, hydrothermal, and alkaline. Hydrothermally pretreated wheat straw gave the highest cellulose conversion with 80% glucose yield and 0.8...

  3. Proteome-wide systems analysis of a cellulosic biofuel-producing microbe

    OpenAIRE

    Chilaka, Amanda C; Tolonen, Andrew; Haas, Wilhelm; Aach, John Dennis; Gygi, Steven P.; Church, George McDonald

    2011-01-01

    Cellulose is the world's most abundant renewable, biological energy source (Leschine, 1995). Microbial fermentation of cellulosic biomass could sustainably provide enough ethanol for 65% of US ground transportation fuel at current levels (Somerville, 2006). However, cellulose in plant biomass is packaged into a crystalline matrix, making biomass deconstruction a key roadblock to using it as a feedstock (Houghton et al, 2006). A promising strategy to overcome biomass recalcitrance is consolida...

  4. 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......-based fibres 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....

  5. Essays concerning the cellulosic biofuel industry

    Science.gov (United States)

    Rosburg, Alicia Sue

    Despite market-based incentives and mandated production, the U.S. cellulosic biofuel industry has been slow to develop. This dissertation explores the economic factors that have limited industry development along with important economic tradeoffs that will be encountered with commercial-scale production. The first essay provides an overview of the policies, potential, and challenges of the biofuel industry, with a focus on cellulosic biofuel. The second essay considers the economics of cellulosic biofuel production. Breakeven models of the local feedstock supply system and biofuel refining process are constructed to develop the Biofuel Breakeven (BioBreak) program, a stochastic, Excel-based program that evaluates the feasibility of local biofuel and biomass markets under various policy and market scenarios. An application of the BioBreak program is presented using expected market conditions for 14 local cellulosic biofuel markets that vary by feedstock and location. The economic costs of biofuel production identified from the BioBreak application are higher than frequently anticipated and raise questions about the potential of cellulosic ethanol as a sustainable and economical substitute for conventional fuels. Program results also are extended using life-cycle analysis to evaluate the cost of reducing GHG emissions by substituting cellulosic ethanol for conventional fuel. The third essay takes a closer look at the economic trade-offs within the biorefinery industry and feedstock production processes. A long-run biomass production through bioenergy conversion cost model is developed that incorporates heterogeneity of biomass suppliers within and between local markets. The model builds on previous literature by treating biomass as a non-commoditized feedstock and relaxes the common assumption of fixed biomass density and price within local markets. An empirical application is provided for switchgrass-based ethanol production within U.S. crop reporting districts

  6. 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.

  7. Cellulose synthase interacting protein: A new factor in cellulose synthesis

    OpenAIRE

    Gu, Ying; Somerville, Chris

    2010-01-01

    Cellulose is the most abundant biopolymer on earth. The great abundance of cellulose places it at the forefront as a primary source of biomass for renewable biofuels. However, the knowledge of how plant cells make cellulose remains very rudimentary. Cellulose microfibrils are synthesized at the plasma membrane by hexameric protein complexes, also known as cellulose synthase complexes. The only known components of cellulose synthase complexes are cellulose synthase (CESA) proteins until the re...

  8. Comparative Ethanol Productivities of Two Different Recombinant Fermenting Strains on Source-Separated Organic Waste

    Directory of Open Access Journals (Sweden)

    Valeriy Bekmuradov

    2014-10-01

    Full Text Available Production of biofuel such as ethanol from lignocellulosic biomass is a beneficial way to meet sustainability and energy security in the future. The main challenge in bioethanol conversion is the high cost of processing, in which enzymatic hydrolysis and fermentation are the major steps. Among the strategies to lower processing costs are utilizing both glucose and xylose sugars present in biomass for conversion. An approach featuring enzymatic hydrolysis and fermentation steps, identified as separate hydrolysis and fermentation (SHF was used in this work. Proposed solution is to use "pre-processing" technologies, including the thermal screw press (TSP and cellulose-organic-solvent based lignocellulose fractionation (COSLIF pretreatments. Such treatments were conducted on a widely available feedstock such as source separated organic waste (SSO to liberate all sugars to be used in the fermentation process. Enzymatic hydrolysis was featured with addition of commercial available enzyme, Accellerase 1500, to mediate enzymatic hydrolysis process. On average, the sugar yield from the TSP and COSLIF pretreatments followed by enzymatic hydrolysis was remarkable at 90%. In this work, evaluation of the SSO hydrolysate obtained from COSLIF and enzymatic hydrolysis pretreaments on ethanol yields was compared by fermentation results with two different recombinant strains: Zymomonas mobilis 8b and Saccharomyces cerevisiae DA2416. At 48 hours of fermentation, ethanol yield was equivalent to 0.48g of ethanol produced per gram of SSO biomass by Z.mobilis 8b and 0.50g of ethanol produced per gram of SSO biomass by S. cerevisiae DA2416. This study provides important insights for investigation of the source-separated organic (SSO waste on ethanol production by different strains and becomes a useful tool to facilitate future process optimization for pilot scale facilities.

  9. 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.

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

    International Nuclear Information System (INIS)

    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. PEI detoxification of pretreated spruce for high solids ethanol fermentation

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...

  12. Kinetics of SO2-ethanol-water (AVAP®) fractionation of sugarcane straw.

    Science.gov (United States)

    You, Xiang; van Heiningen, Adriaan; Sixta, Herbert; Iakovlev, Mikhail

    2016-07-01

    Kinetics of SO2-ethanol-water (AVAP®) fractionation was determined for sugarcane (SC) straw in terms of pulp composition (non-carbohydrate components, cellulose, hemicelluloses) and properties (kappa number, pulp intrinsic viscosity in CED and cellulose degree of polymerization). Effect of temperature (135-165°C) and time (18-118min) was studied at fixed liquor composition (SO2/ethanol/water=12:22.5:65.5, w/w) and a liquor-to-solid ratio (4Lkg(-1)). Interpretation is given in terms of major fractionation reactions, removal of non-carbohydrate components and xylan, as well as acid hydrolysis of cellulose, and is compared to other lignocellulosic substrates (beech, spruce and wheat straw). Overall, SO2-ethanol-water process efficiently fractionates SC straw by separating cellulose from both non-carbohydrate components and xylan while reducing cellulose DP. PMID:27089426

  13. Tolerant yeast in situ detoxifies major class of toxic chemicals while producing ethanol

    Science.gov (United States)

    Renewable lignocellulosic materials contain abundant sugar source and biofuels conversion including cellulosic ethanol production from lignocellulosic biomass provides a sustainable alternative energy resource for a cleaner environment. In order to release the biomass sugars from the complex cellulo...

  14. The Canadian Petroleum Products Institute : position on ethanol

    International Nuclear Information System (INIS)

    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

  15. Beyond commonplace biofuels: Social aspects of ethanol

    International Nuclear Information System (INIS)

    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

  16. Product inhibition of enzymatic hydrolysis of cellulose: are we running the reactions all wrong?

    DEFF Research Database (Denmark)

    Meyer, Anne S.

    2012-01-01

    Enzyme catalyzed deconstruction of cellulose to glucose is an important technology step in lignocellulose-to-ethanol processing as well as in the future biorefinery based production of novel products to replace fossil oil based chemistry. The main goals of the enzymatic biomass saccharification i....... Based on cellulose inhibition kinetics the talk will illustrate the suitability of membrane reactor technology for improving cellulose substrate conversion efficiency.......Enzyme catalyzed deconstruction of cellulose to glucose is an important technology step in lignocellulose-to-ethanol processing as well as in the future biorefinery based production of novel products to replace fossil oil based chemistry. The main goals of the enzymatic biomass saccharification...... include high substrate conversion (maximal yields), maximal enzyme efficiency, maximal volumetric reactor productivity, minimal equipment investment, minimal size, and short reaction time. The classic batch type STR reactions used for enzymatic cellulose hydrolysis prevent these goals to be fulfilled...

  17. 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.

  18. Cellulose-silica aerogels.

    Science.gov (United States)

    Demilecamps, Arnaud; Beauger, Christian; Hildenbrand, Claudia; Rigacci, Arnaud; Budtova, Tatiana

    2015-05-20

    Aerogels based on interpenetrated cellulose-silica networks were prepared and characterised. Wet coagulated cellulose was impregnated with silica phase, polyethoxydisiloxane, using two methods: (i) molecular diffusion and (ii) forced flow induced by pressure difference. The latter allowed an enormous decrease in the impregnation times, by almost three orders of magnitude, for a sample with the same geometry. In both cases, nanostructured silica gel was in situ formed inside cellulose matrix. Nitrogen adsorption analysis revealed an almost threefold increase in pores specific surface area, from cellulose aerogel alone to organic-inorganic composite. Morphology, thermal conductivity and mechanical properties under uniaxial compression were investigated. Thermal conductivity of composite aerogels was lower than that of cellulose aerogel due to the formation of superinsulating mesoporous silica inside cellulose pores. Furthermore, composite aerogels were stiffer than each of reference aerogels. PMID:25817671

  19. Evaluating possible cap and trade legislation on cellulosic feedstock availability

    Energy Technology Data Exchange (ETDEWEB)

    Hellwinckel, Chad [Agricultural Policy Analysis Center, University of Tennessee; de la Torre Ugarte, Daniel [University of Tennessee; Perlack, Robert D [ORNL; West, T. O. [University of Maryland

    2010-11-01

    An integrated, socioeconomic biogeophysical model is used to analyze the interactions of cap-and-trade legislation and the Renewable Fuels Standard. Five alternative policy scenarios were considered with the purpose of identifying policies that act in a synergistic manner to reduce carbon emissions, increase economic returns to agriculture, and adequately meet ethanol mandates. We conclude that climate and energy policies can best be implemented together by offering carbon offset payments to conservation tillage, herbaceous grasses for biomass, and by constraining crop residue removal for ethanol feedstocks to carbon neutral level. When comparing this scenario to the Baseline scenario, the agricultural sector realizes an economic benefit of US$156 billion by 2030 and emissions are reduced by 135 Tg C-equivalent (Eq) yr 1. Results also indicate that geographic location of cellulosic feedstocks could shift significantly depending on the final policies implemented in cap and trade legislation. Placement of cellulosic ethanol facilities should consider these possible shifts when determining site location.

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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)

  2. Clostridium thermocellum ATCC27405 transcriptomic, metabolomic and proteomic profiles after ethanol stress

    OpenAIRE

    Yang Shihui; Giannone Richard J; Dice Lezlee; Yang Zamin K; Engle Nancy L; Tschaplinski Timothy J; Hettich Robert L; Brown Steven D

    2012-01-01

    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...

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

    International Nuclear Information System (INIS)

    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 hm3 of ethanol by 2030 and 3.8 hm3 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    De La Torre Ugarte, Daniel G.; He, Lixia; Jensen, Kimberly L.; English, Burton C. [Department of Agricultural and Resource Economics, University of Tennessee, 302 Morgan Hall, Knoxville, TN 37996-4518 (United States)

    2010-11-15

    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{sup 3} of ethanol by 2030 and 3.8 hm{sup 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)

  5. 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.

  6. 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.

  7. 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...... 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...... 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...

  8. Fuel ethanol production from mixed office paper using recombinant Klebsiella oxytoca P2 containing the Zymomonas mobilis ethanol pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ingram, L.O.; Brooks, T.A. [Univ. of Florida, Gainesville, FL (United States)

    1995-12-01

    Mixed Office Waste Paper (MOWP) is an excellent substrate for repulsing or for conversion into fuel ethanol. We have developed a recombinant strain of K. oxytoca which ferments cellobiose and cellotriose to ethanol at near theoretical yield (pH 5-5.2, 35{degrees}C), eliminating the need for external {beta}-glucosidase. This organism was tested with commercial fungal cellulose in optimized simultaneous saccharification and fermentation experiments using autoclaved MOWP and dilute acid hydrolyzed-MOWT (hydrolyzes hemicellulose and starch) as substrates. Essentially identical rates and yields were obtained with both substrates on a dry weight basis, although initial mixing was easier after acid pretreatment. Under optimal conditions, 5 % ethanol (v/v) was produced in 72 h with low levels of cellulose (5 FPU cellulose average/g paper) during 4 successive fermentations in which cellulose enzymes were recycled. The estimated yield for this process is 0.42 g ethanol/gram dry wt of paper, 538 liters ethanol/ metric ton, 125 gallons/U.S. ton. An adaptation of this process may also be useful as a treatment for sludges from paper recycling.

  9. Ethanol production from potato peel waste (PPW).

    Science.gov (United States)

    Arapoglou, D; Varzakas, Th; Vlyssides, A; Israilides, C

    2010-10-01

    Considerable concern is caused by the problem of potato peel waste (PPW) to potato industries in Europe. An integrated, environmentally-friendly solution is yet to be found and is currently undergoing investigation. Potato peel is a zero value waste produced by potato processing plants. However, bio-ethanol produced from potato wastes has a large potential market. If Federal Government regulations are adopted in light of the Kyoto agreement, the mandatory blending of bio-ethanol with traditional gasoline in amounts up to 10% will result in a demand for large quantities of bio-ethanol. PPW contain sufficient quantities of starch, cellulose, hemicellulose and fermentable sugars to warrant use as an ethanol feedstock. In the present study, a number of batches of PPW were hydrolyzed with various enzymes and/or acid, and fermented by Saccharomyces cerevisae var. bayanus to determine fermentability and ethanol production. Enzymatic hydrolysis with a combination of three enzymes, released 18.5 g L(-1) reducing sugar and produced 7.6 g L(-1) of ethanol after fermentation. The results demonstrate that PPW, a by-product of the potato industry features a high potential for ethanol production. PMID:20471817

  10. Perspectives on fuel ethanol consumption and trade

    International Nuclear Information System (INIS)

    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)

  11. Effects of Pithecellobium Jiringa Ethanol Extract against Ethanol-Induced Gastric Mucosal Injuries in Sprague-Dawley Rats

    OpenAIRE

    Fouad Hussain AL-Bayaty; Siddig Ibrahim Abdelwahab; Nimir, Amal R.; Suhailah Wasmn Qader; Mahmood Ameen Abdulla; Ibrahim Abdel Aziz Ibrahim

    2012-01-01

    Current anti-gastric ulcer agents have side effects, despite the progression and expansion of advances in treatment. This study aimed to investigate the gastroprotective mechanisms of Pithecellobium jiringa ethanol extract against ethanol-induced gastric mucosal ulcers in rats. For this purpose, Sprague Dawley rats were randomly divided into five groups: Group 1 (normal control) rats were orally administered with vehicle (carboxymethyl cellulose), Group 2 (ulcer control) rats were also orally...

  12. Net-Immobilization of β-glucosidase on Nonwoven Fabrics to Lower the Cost of “Cellulosic Ethanol” and Increase Cellulose Conversions

    OpenAIRE

    Xing Zhu; Bin He; Changwen Zhao; Rong Fan; Lihua Zhang; Guan Wang; Yuhong Ma; Wantai Yang

    2016-01-01

    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 ...

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

    DEFF Research Database (Denmark)

    Qiang, zhang; Thomsen, Anne Belinda

    2012-01-01

    In order to find out appropriate process for ethanol production from corn stover, wet oxidation (195°C, 15 minutes) and simultaneous saccharification and fermentation (SSF) was carried out to produce ethanol. The results showed that the cellulose recovery of 92.9% and the hemicellulose recovery of...

  14. Ethanol production from lignocellulosic biomass; Production d`ethanol a partir de biomasse lignocellulosique

    Energy Technology Data Exchange (ETDEWEB)

    Ogier, J.C.; Leygue, J.P. [Cerealiers de France, 75 - Paris (France); Ballerini, D. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France); Rigal, L. [Ecole Nationale Superieure de Chimie, 31 - Toulouse (France). Institut National polytechnique; Pourquie, J. [Institut National Agronomique, 78 - Thiverval-Grignon (France)

    1999-10-01

    The reported study intends to describe the state of the art in the domain of ethanol production from lignocellulosic biomass. Its first goal was to pinpoint the main technical and economical bottlenecks of the processes which are today under consideration, and to identify which research and development efforts could be implemented to overcome them (in the short or middle term). Lignocellulosic biomass is a complex substrate, and essentially made of cellulose, hemi-cellulose and lignin. The processes which have been considered, attempt to recover a maximum amount of sugars from the hydrolysis of cellulose and hemi-cellulose, and to ferment them into ethanol. The hydrolysis processes used in the past are essentially chemical processes, but the acid recovery costs and the formation of toxic products make them uncompetitive. They are now substituted by enzymatic processes, which are more specific and allow higher hydrolysis yields under less severe conditions. However, the cellulose that is the target of the enzymatic hydrolysis, is not directly accessible to the enzymes. It is the reason why a pretreatment step has to precede the enzymatic hydrolysis. Different types of pretreatment have been studied, but three methods appear more efficient: dilute acid hydrolysis, steam explosion with catalyst addition and thermo-hydrolysis. These pretreatments could result in high hydrolysis yields of the cellulose fraction (close to 100 %), and in a maximum recovery of the sugars from the hemi-cellulosic fraction. Enzymatic hydrolysis has yet to be improved in order to reduce the cost of consumption of the enzymes. Research works will have to focus upon the enzyme specific activity, in order to achieve higher efficiencies such as those obtained with amylases. The SSF (Saccharification and Simultaneous Fermentation) process improves the enzyme efficiency by reducing the feed-back inhibition from the hydrolysis products. The screening of efficient fermentative microorganisms under

  15. National Geo-Database for Biofuel Simulations and Regional Analysis of Biorefinery Siting Based on Cellulosic Feedstock Grown on Marginal Lands

    Energy Technology Data Exchange (ETDEWEB)

    Izaurralde, Roberto C.; Zhang, Xuesong; Sahajpal, Ritvik; Manowitz, David H.

    2012-04-01

    The goal of this project undertaken by GLBRC (Great Lakes Bioenergy Research Center) Area 4 (Sustainability) modelers is to develop a national capability to model feedstock supply, ethanol production, and biogeochemical impacts of cellulosic biofuels. The results of this project contribute to sustainability goals of the GLBRC; i.e. to contribute to developing a sustainable bioenergy economy: one that is profitable to farmers and refiners, acceptable to society, and environmentally sound. A sustainable bioenergy economy will also contribute, in a fundamental way, to meeting national objectives on energy security and climate mitigation. The specific objectives of this study are to: (1) develop a spatially explicit national geodatabase for conducting biofuel simulation studies and (4) locate possible sites for the establishment of cellulosic ethanol biorefineries. To address the first objective, we developed SENGBEM (Spatially Explicit National Geodatabase for Biofuel and Environmental Modeling), a 60-m resolution geodatabase of the conterminous USA containing data on: (1) climate, (2) soils, (3) topography, (4) hydrography, (5) land cover/ land use (LCLU), and (6) ancillary data (e.g., road networks, federal and state lands, national and state parks, etc.). A unique feature of SENGBEM is its 2008-2010 crop rotation data, a crucially important component for simulating productivity and biogeochemical cycles as well as land-use changes associated with biofuel cropping. ARRA support for this project and to the PNNL Joint Global Change Research Institute enabled us to create an advanced computing infrastructure to execute millions of simulations, conduct post-processing calculations, store input and output data, and visualize results. These computing resources included two components installed at the Research Data Center of the University of Maryland. The first resource was 'deltac': an 8-core Linux server, dedicated to county-level and state-level simulations

  16. Statistical analysis of optimal culture conditions for Gluconacetobacter hansenii cellulose production

    Energy Technology Data Exchange (ETDEWEB)

    Hutchens, Stacy A [ORNL; Leon, R. V. [University of Tennessee, Knoxville (UTK); O' Neill, Hugh Michael [ORNL; Evans, Barbara R [ORNL

    2007-01-01

    The purpose of this study was to analyze the effects of different culture parameters on Gluconacetobacter hansenii (ATCC 10821) to determine which conditions provided optimum cellulose growth. Five culture factors were investigated: carbon source, addition of ethanol, inoculation ratio, pH and temperature. JMP Software (SAS, Cary, NC, USA) was used to design this experiment using a fractional factorial design. After 22 days of static culture, the cellulose produced by the bacteria was harvested, purified and dried to compare the cellulose yields. The results were analyzed by fitting the data to a first-order model with two-factor interactions. The study confirmed that carbon source, addition of ethanol, and temperature were significant factors in the production of cellulose of this G. hansenii strain. While pH alone does not significantly affect average cellulose production, cellulose yields are affected by pH interaction with the carbon source. Culturing the bacteria on glucose at pH 6-5 produces more cellulose than at pH 5-5, while using mannitol at pH 5-5 produces more cellulose than at pH 6-5. The bacteria produced the most cellulose when cultured on mannitol, at pH 5-5, without ethanol, at 20 C. Inoculation ratio was not found to be a significant factor or involved in any significant two-factor interaction. These findings give insight into the conditions necessary to maximize cellulose production from this G. hansenii strain. In addition, this work demonstrates how the fractional factorial design can be used to test a large number of factors using an abbreviated set of experiments. Fitting a statistical model determined the significant factors as well as the significant two-factor interactions.

  17. Technology and economics of conversion of cellulose (wood) and corn starch to sugars, alcohol and yeast. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wolnak, B.

    1978-08-01

    The present status of the technology and economics for the production of glucose, alcohol, and yeast from cellulose (wood), corn starch, and molasses is analyzed. The basic processes for producing glucose and the factors affecting the economics of its production are reviewed. The costs of producing ethanol and yeast from the glucose are derived. Market availability of glucose, ethanol, and yeast is surveyed. (JSR)

  18. What Do We Know About Ethanol and Alkylates as Pollutants?

    Energy Technology Data Exchange (ETDEWEB)

    Rich, D W; Marchetti, A A; Buscheck, T; Layton, D W

    2001-05-11

    Gov. Davis issued Executive Order D-5-99 in March 1999 calling for removal of methyl tertiary butyl ether (MTBE) from gasoline no later than December 31, 2002. The Executive Order required the California Air Board, State Water Resources Control Board (SWRCB) and Office of Environmental Health Hazard Assessment (OEHHA) to prepare an analysis of potential impacts and health risks that may be associated with the use of ethanol as a fuel oxygenate. The SWRCB contracted with the Lawrence Livermore National Laboratory (LLNL) to lead a team of researchers, including scientists from Clarkson University, University of Iowa, and University of California, Davis, in evaluating the potential ground and surface water impacts that may occur if ethanol is used to replace MTBE. These findings are reported in the document entitled Health and Environmental Assessment of the Use of Ethanol as a Fuel Oxygenate. This document has been peer reviewed and presented to the California Environmental Policy Council and may be viewed at: http://www-erd.llnl.gov/ethanol/. Ethanol used for fuels is made primarily from grains, but any feed stock containing sugar, starch, or cellulose can be fermented to ethanol. Ethanol contains 34.7% oxygen by weight. It is less dense than water, but infinitely soluble in water. Ethanol vapors are denser than air. One and a half gallons of ethanol have the same energy as one gallon of gasoline. Pure fuel ethanol, and gasoline with ethanol, conducts electricity, while gasoline without ethanol is an insulator. Corrosion and compatibility of materials is an issue with the storage of pure ethanol and gasoline with high percentages of ethanol, but these issues are less important if gasoline with less than 10% ethanol is used.

  19. Cellulose Synthesis and Its Regulation

    OpenAIRE

    Li, Shundai; Bashline, Logan; Lei, Lei; Gu, Ying

    2014-01-01

    Cellulose, the most abundant biopolymer synthesized on land, is made of linear chains of ß (1–4) linked D-glucose. As a major structural component of the cell wall, cellulose is important not only for industrial use but also for plant growth and development. Cellulose microfibrils are tethered by other cell wall polysaccharides such as hemicellulose, pectin, and lignin. In higher plants, cellulose is synthesized by plasma membrane-localized rosette cellulose synthase complexes. Despite the re...

  20. Fuel ethanol production using nuclear-plant steam

    International Nuclear Information System (INIS)

    In the United States, the production of fuel ethanol from corn for cars and light trucks has increased from about 6 billion liters per year in 2000 to 19 billion liters per year in 2006. A third of the world's liquid fuel demands could ultimately be obtained from biomass. The production of fuel ethanol from biomass requires large quantities of steam. For a large ethanol plant producing 380 million liters of fuel ethanol from corn per year, about 80 MW(t) of 1-MPa (∼180 deg. C) steam is required. Within several decades, the steam demand for ethanol plants in the United States is projected to be tens of gigawatts, with the worldwide demand being several times larger. This market may become the largest market for cogeneration of steam from nuclear electric power plants. There are strong incentives to use steam from nuclear power plants to meet this requirement. The cost of low-pressure steam from nuclear power plants is less than that of natural gas, which is now used to make steam in corn-to-ethanol plants. Steam from nuclear power plants reduces greenhouse gases compared with steam produced from fossil fuels. While ethanol is now produced from sugarcane and corn, the next-generation ethanol plants will use more abundant cellulose feedstocks. It is planned that these plants will burn the lignin in the cellulosic feedstocks to provide the required steam. Lignin is the primary non-sugar-based component in cellulosic biomass that can not be converted to ethanol. Low-cost steam from nuclear plants creates the option of converting the lignin to other liquid fuels and thus increase the liquid fuel production per unit of biomass. Because liquid fuel production from biomass is ultimately limited by the availability of biomass, steam from nuclear plants can ultimately increase the total liquid fuels produced from biomass. (author)

  1. Converting Municipal Waste into Automobile Fuel: Ethanol from Newspaper

    Science.gov (United States)

    Mascal, Mark; Scown, Richard

    2008-01-01

    Waste newspaper is pulped with acid and its cellulose is hydrolyzed. The resulting glucose syrup is fermented with yeast and distilled to give ethanol. The experiment highlights the potential of applied chemistry to confront problems of economic importance, that is, the effective utilization of biomass to reduce dependence on non-renewable…

  2. Fuel ethanol production from alkaline peroxide pretreated corn stover

    Science.gov (United States)

    Corn stover (CS) has the potential to serve as an abundant low-cost feedstock for production of fuel ethanol. Due to heterogeneous complexity and recalcitrance of lignocellulosic feedstocks, pretreatment is required to break the lignin seal and/or disrupt the structure of crystalline cellulose to in...

  3. Ethanol from lignocellulosic biomasses

    International Nuclear Information System (INIS)

    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 2200C 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

  4. Cellulose- and Xylan-Degrading Thermophilic Anaerobic Bacteria from Biocompost ▿ †

    OpenAIRE

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

    2011-01-01

    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 xy...

  5. Access to cellulose limits the efficiency of enzymatic hydrolysis: the role of amorphogenesis

    OpenAIRE

    Saddler Jack N; Arantes Valdeir

    2010-01-01

    Abstract The efficient enzymatic saccharification of cellulose at low cellulase (protein) loadings continues to be a challenge for commercialization of a process for bioconversion of lignocellulose to ethanol. Currently, effective pretreatment followed by high enzyme loading is needed to overcome several substrate and enzyme factors that limit rapid and complete hydrolysis of the cellulosic fraction of biomass substrates. One of the major barriers faced by cellulase enzymes is their limited a...

  6. Cellulosic biomass could help meet California’s transportation fuel needs

    OpenAIRE

    Wyman, Charles E; Yang, Bin

    2009-01-01

    Cellulosic biomass, which includes agricultural and forestry residues and woody and herbaceous plants, is the only low-cost resource that can support the sustainable production of liquid fuels on a large enough scale to significantly address our transportation energy needs. The biological conversion of cellulosic biomass to ethanol could offer high yields at low costs, but only if we can improve the technology for releasing simple sugars from recalcitrant biomass. We review key aspects of cel...

  7. Photoresponsive Cellulose Nanocrystals

    Directory of Open Access Journals (Sweden)

    Dimitris S Argyropoulos

    2011-07-01

    Full Text Available In this communication a method for the creation of fluorescent cellulose nanoparticles using click chemistry and subsequent photodimerization of the installed side‐ chains is demonstrated. In the first step, the primary hydroxyl groups on the surface of the CNCs were converted to carboxylic acids by using TEMPO‐mediated hypohalite oxidation. The alkyne groups, essential for the click reaction, were introduced into the surface of TEMPO‐ oxidized CNCs via carbodiimide‐mediated formation of an amide linkage between monomers carrying an amine functionality and carboxylic acid groups on the surface of the TEMPO‐oxidized CNCs. Finally, the reaction of surface‐modified TEMPO‐oxidized cellulose nanocrystals and azido‐bearing coumarin and anthracene monomers were carried out by means of a click chemistry, i.e., Copper(I‐catalyzed Azide‐Alkyne Cycloaddition (CuAAC to produce highly photo‐responsive and fluorescent cellulose nanoparticles. Most significantly, the installed coumarin and/or anthracene side‐chains were shown to undergo UV‐induced [2+2] and [4+4] cycloaddition reactions, bringing and locking the cellulose nanocrystals together. This effort paves the way towards creating, cellulosic photo responsive nano‐arrays with the potential of photo reversibility since these reactions are known to be reversible at varying wavelengths.

  8. 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

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

    OpenAIRE

    Carol López de Dicastillo; Rosa Navarro (Ilustradora); Abel Guarda; Maria José Galotto

    2015-01-01

    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-a...

  10. Electrochemical synthesis of cellulose mesylate

    Science.gov (United States)

    Khidirov, Sh Sh; Akhmedov, M. A.; Khibiev, H. S.

    2016-04-01

    The article deal with the possibility anode modification of cellulose to form its ester - mesylate by voltametric measurement method and preparative electrosynthesis on a platinum electrode in the system cellulose - dimethyl sulfoxide - methanesulfonic

  11. Structure of cellulose acetobacter xylinum

    International Nuclear Information System (INIS)

    The data are presented on optimization of cellulose synthesis by Acetobacter xylinum (strain VKM V-880) and the structural characteristics of A. xylinum cellulose gel film synthesized during static cultivation. The structural changes caused by the removal of water from gel films are established and the structural organization of macromolecular chains in cellulose A. xylinum is studied

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

    International Nuclear Information System (INIS)

    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

  13. 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.

  14. Cellulose Microfibril Formation by Surface-Tethered Cellulose Synthase Enzymes.

    Science.gov (United States)

    Basu, Snehasish; Omadjela, Okako; Gaddes, David; Tadigadapa, Srinivas; Zimmer, Jochen; Catchmark, Jeffrey M

    2016-02-23

    Cellulose microfibrils are pseudocrystalline arrays of cellulose chains that are synthesized by cellulose synthases. The enzymes are organized into large membrane-embedded complexes in which each enzyme likely synthesizes and secretes a β-(1→4) glucan. The relationship between the organization of the enzymes in these complexes and cellulose crystallization has not been explored. To better understand this relationship, we used atomic force microscopy to visualize cellulose microfibril formation from nickel-film-immobilized bacterial cellulose synthase enzymes (BcsA-Bs), which in standard solution only form amorphous cellulose from monomeric BcsA-B complexes. Fourier transform infrared spectroscopy and X-ray diffraction techniques show that surface-tethered BcsA-Bs synthesize highly crystalline cellulose II in the presence of UDP-Glc, the allosteric activator cyclic-di-GMP, as well as magnesium. The cellulose II cross section/diameter and the crystal size and crystallinity depend on the surface density of tethered enzymes as well as the overall concentration of substrates. Our results provide the correlation between cellulose microfibril formation and the spatial organization of cellulose synthases. PMID:26799780

  15. Bio ethanol production from oil palm empty fruit bunches

    International Nuclear Information System (INIS)

    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)

  16. 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)

  17. CHARACTERIZATION OF REGENERATED CELLULOSE MEMBRANES HYDROLYZED FROM CELLULOSE ACETATE

    Institute of Scientific and Technical Information of China (English)

    Yun Chen; Xiao-peng Xiong; Guang Yang; Li-na Zhang; Sen-lin Lei; Hui Lianga

    2002-01-01

    A series of cellulose acetate membranes were prepared by using formamide as additive, and then were hydrolyzedin 4 wt% aqueous NaOH solution for 8 h to obtain regenerated cellulose membranes. The dependence of degree ofsubstitution, structure, porous properties, solubility and thermal stability on hydrolysis time was studied by chemical titration,Fourier transform infrared spectroscopy, scanning electron microscopy, wide-angle X-ray diffraction, and differentialscanning calorimetry, respectively. The results indicated that the pore size of the regenerated cellulose membranes wasslightly smaller than that of cellulose acetate membrane, while solvent-resistance, crystallinity and thermostability weresignificantly improved. This work provides a simple way to prepare the porous cellulose membranes, which not only kept thegood pore characteristics of cellulose acetate membranes, but also possessed solvent-resistance, high crystallinity andthermostability. Therefore, the application range of cellulose acetate membranes can be expanded.

  18. Degradation of cellulose in irradiated wood and purified celluloses

    International Nuclear Information System (INIS)

    The degradation of cellulose chains in Pinus radiata and Eucalyptus regnans given small gamma-radiation doses has been studied. Scission yields showed marked dose-dependency effects, of which some appear to be due to an inherent dose-dependency exhibited by cellulose itself, and others indicate a protective action of some natural wood constituents. A uniform treatment of viscometry data reported by various workers who have studied radiation-induced degradation of purified cellulose materials, has been used to enable their scission results to be compared with each other and with those for natural wood cellulose of various dose levels. Generally, cellulose in wood is less degraded by radiation than is purified cellulose. However, with Eucalyptus regnans remarkably high scission yields, significantly higher than expected for purified cellulose, were observed at dose levels of 0.5-1.0 x 104Gy. The relevance of these results to changes in pulp yield following irradiation of wood chips, is briefly discussed. (author)

  19. Ultrasound stimulated release of mimosa medicine from cellulose hydrogel matrix.

    Science.gov (United States)

    Jiang, Huixin; Tovar-Carrillo, Karla; Kobayashi, Takaomi

    2016-09-01

    Ultrasound (US) drug release system using cellulose based hydrogel films was developed as triggered to mimosa. Here, the mimosa, a fascinating drug to cure injured skin, was employed as the loading drug in cellulose hydrogel films prepared with phase inversion method. The mimosa hydrogels were fabricated from dimethylacetamide (DMAc)/LiCl solution in the presence of mimosa, when the solution was exposed to ethanol vapor. The US triggered release of the mimosa from the hydrogel matrix was carried out under following conditions of US powers (0-30W) and frequencies (23, 43 and 96kHz) for different mimosa hydrogel matrix from 0.5wt% to 2wt% cellulose solution. To release the drug by US trigger from the matrix, the better medicine release was observed in the matrix prepared from the 0.5wt% cellulose solution when the 43kHz US was exposed to the aqueous solution with the hydrogel matrix. The release efficiency increased with the increase of the US power from 5 to 30W at 43kHz. Viscoelasticity of the hydrogel matrix showed that the hydrogel became somewhat rigid after the US exposure. FT-IR analysis of the mimosa hydrogel matrixes showed that during the US exposure, hydrogen bonds in the structure of mimosa-water and mimosa-cellulose were broken. This suggested that the enhancement of the mimosa release was caused by the US exposure. PMID:27150786

  20. 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

  1. Cysticercosis cellulose cutis

    Directory of Open Access Journals (Sweden)

    Inamadar Arun

    2001-01-01

    Full Text Available A woman aged 30 years with solitary lesion of cysticercosis cellulose cutis is reported. Cutaneous cysticerci are often a pointer to the involvement of internal organs. Our patient was a pure vegetarian so, probable mode of infection may be ingestion of contaminated vegetables, where the practice of using pig feces as manure is prevalent.

  2. Derivatives of Oxidized Cellulose

    Czech Academy of Sciences Publication Activity Database

    Taubner, T.; Sobek, Jiří; Havelka, P.; Kvasnička, F.; Synytsya, A.; Čopíková, J.

    Praha : Česká společnost chemická, 2009, s. 777. ISSN 0009-2770. [International Conference on Polysaccharides-Glycoscience 2009 /5./. Praha (CZ), 11.11.2009-13.11.2009] Institutional research plan: CEZ:AV0Z40720504 Keywords : cellulose * reaction progress * chromatography Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  3. Nonrenewable energy cost of corn-ethanol in China

    International Nuclear Information System (INIS)

    Nonrenewable energy cost is accounted for the believed renewable biofuel of corn-ethanol in China. By a process-based energy analysis, nonrenewable energy cost in the corn-ethanol production process incorporating agricultural crop production, industrial conversion and wastewater treatment is conservatively estimated as 1.70 times that of the ethanol energy produced, corresponding to a negative energy return in contrast to the positive ones previously reported. Nonrenewable energy cost associated with wastewater treatment usually ignored in previous researches is shown important in the energy balance. Denoting the heavy nonrenewability of the produced corn-ethanol, the calculated nonrenewable energy cost would rise to 3.64 folds when part of the nonrenewable energy cost associated with water consumption, transportation and environmental remediation is included. Due to the coal dominated nonrenewable energy structure in China, corn-ethanol processes in China are mostly a conversion of coal to ethanol. Validations and discussions are also presented to reveal policy implications against corn based ethanol as an alternative energy in long term energy security planning. - Highlights: ► Nonrenewable energy (NE) cost is conservatively accounted for corn-ethanol in China. ► Corn cultivation, ethanol conversion and wastewater treatment are included. ► NE cost is estimated as 1.70 times that of the ethanol energy produced. ► Corn-ethanol processes in China are mostly a conversion of coal to ethanol.

  4. 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

    In order to find out the appropriate process for ethanol production from corn straw, alkaline wet-oxidation pretreatment (195°C, 15 min, Na2CO3 2 g/L, O2 1200 kPa) and simultaneous saccharification and fermentation (SSF) were adopted to produce ethanol. The results showed that 90% of cellulose...... obtained. The estimated total ethanol production was 262.7 kg/t raw material by assuming the consumption of both C-6 and C-5. No obvious inhibition effect occurred during SSF. These offered experiment evidences for ethanol production from corn straw....

  5. 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.

  6. 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

    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 oxidatio...

  7. Pre-treatment of ligno-cellulose with biological acid recycling (the Biosulfurol process)

    NARCIS (Netherlands)

    Groenestijn, van J.W.; Hazewinkel, J.H.O.; Bakker, R.R.

    2008-01-01

    A biomass pretreatment process is being developed based on contacting ligno-cellulosic biomass with 70% sulphuric acid and subsequent hydrolysis by adding water. In this process, the hydrolysate can be fermented yielding ethanol, while the sulphuric acid is partly recovered by anion-selective membra

  8. Hairy cellulose nanocrystalloids: a novel class of nanocellulose.

    Science.gov (United States)

    van de Ven, Theo G M; Sheikhi, Amir

    2016-08-18

    Nanomaterials have secured such a promising role in today's life that imagining the modern world without them is almost impossible. A large fraction of nanomaterials is synthesized from environmentally-dangerous elements such as heavy metals, which have posed serious side-effects to ecosystems. Despite numerous advantages of synthetic nanomaterials, issues such as renewability, sustainability, biocompatibility, and cost efficiency have drawn significant attention towards natural products such as cellulose-based nanomaterials. Within the past decade, nanocelluloses, most remarkably nanocrystalline cellulose (NCC) and nanofibrillated cellulose (NFC), have successfully been used for a wide spectrum of applications spanning from nanocomposites, packaging, and mechanical and rheological property modifications, to chemical catalysis and organic templating. Yet, there has been little effort to introduce fundamentally new polysaccharide-based nanomaterials. We have been able to develop the first kind of cellulose-based nanoparticles bearing both crystalline and amorphous regions. These nanoparticles comprise a crystalline body, similar to conventional NCC, but with polymer chains protruding from both ends; therefore, these particles are called hairy cellulose nanocrystalloids (HCNC). In this article, we touch on the philosophy of HCNC synthesis, the striking superiority over existing nanocelluloses, and applications of this novel class of nanocelluloses. We hope that the emergence of hairy cellulose nanocrystalloids extends the frontiers of sustainable, green nanotechnology. PMID:27453347

  9. High solid simultaneous saccharification and fermentation of wet oxidized corn stover to ethanol

    DEFF Research Database (Denmark)

    Varga, E.; Klinke, H.B.; Reczey, K.;

    2004-01-01

    In this study ethanol was produced from corn stover pretreated by alkaline and acidic wet oxidation (WO) (195 degreesC, 15 min, 12 bar oxygen) followed by nonisothermal simultaneous saccharification and fermentation (SSF). In the first step of the SSF, small amounts of cellulases were added at 50....../L) were present in the hemicellulose rich hydrolyzate at subinhibitory levels, thus no detoxification was needed prior to SSF of the whole slurry. Based on the cellulose available in the WO corn stover 83% of the theoretical ethanol yield was obtained under optimized SSF conditions. This was achieved with...... a substrate concentration of 12% dry matter (DM) acidic WO corn stover at 30 FPU/g DM (43.5 FPU/g cellulose) enzyme loading. Even with 20 and 15 FPU/g DM (corresponding to 29 and 22 FPU/g cellulose) enzyme loading, ethanol yields of 76 and 73%, respectively, were obtained. After 120 h of SSF the...

  10. 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 of...

  11. 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. PMID:26572341

  12. Increase in ethanol yield via elimination of lactate production in an ethanol-tolerant mutant of Clostridium thermocellum.

    Directory of Open Access Journals (Sweden)

    Ranjita Biswas

    Full Text Available Large-scale production of lignocellulosic biofuel is a potential solution to sustainably meet global energy needs. One-step consolidated bioprocessing (CBP is a potentially advantageous approach for the production of biofuels, but requires an organism capable of hydrolyzing biomass to sugars and fermenting the sugars to ethanol at commercially viable titers and yields. Clostridium thermocellum, a thermophilic anaerobe, can ferment cellulosic biomass to ethanol and organic acids, but low yield, low titer, and ethanol sensitivity remain barriers to industrial production. Here, we deleted the hypoxanthine phosphoribosyltransferase gene in ethanol tolerant strain of C. thermocellum adhE*(EA in order to allow use of previously developed gene deletion tools, then deleted lactate dehydrogenase (ldh to redirect carbon flux towards ethanol. Upon deletion of ldh, the adhE*(EA Δldh strain produced 30% more ethanol than wild type on minimal medium. The adhE*(EA Δldh strain retained tolerance to 5% v/v ethanol, resulting in an ethanol tolerant platform strain of C. thermocellum for future metabolic engineering efforts.

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

    International Nuclear Information System (INIS)

    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 13C. 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)

  14. ENZYME-BASED HYDROLYSIS PROCESSES FOR ETHANOL

    Directory of Open Access Journals (Sweden)

    Keikhosro Karimi

    2007-11-01

    Full Text Available This article reviews developments in the technology for ethanol produc-tion from lignocellulosic materials by “enzymatic” processes. Several methods of pretreatment of lignocelluloses are discussed, where the crystalline structure of lignocelluloses is opened up, making them more accessible to the cellulase enzymes. The characteristics of these enzymes and important factors in enzymatic hydrolysis of the cellulose and hemicellulose to cellobiose, glucose, and other sugars are discussed. Different strategies are then described for enzymatic hydrolysis and fermentation, including separate enzymatic hydrolysis and fermentation (SHF, simultaneous saccharification and fermentation (SSF, non-isothermal simultaneous saccharification and fermentation (NSSF, simultaneous saccharification and co-fermentation (SSCF, and consolidated bioprocessing (CBP. Furthermore, the by-products in ethanol from lignocellulosic materials, wastewater treatment, commercial status, and energy production and integration are reviewed.

  15. Preliminary study for optimization of enzymatic hydrolysis of waste cellulosic materials

    Directory of Open Access Journals (Sweden)

    LUMINITA GEORGESCU

    2011-07-01

    Full Text Available Lignocellulose is a generic term describing the main constituents in most plants, namely cellulose, hemicelluloses, and lignin. Cellulose is a glucose polysaccharide, hemicelluloses are polysaccharides with a backbone of different hexoses (glucose, mannose, galactose and pentoses (xylan, arabinose, and lignin is a complex network of different phenyl propane units. The cellulosic materials are potential sources of ethanol. Steps of this process are saccharification of cellulose to reduce sugars, under enzymes action and to reduce sugars fermentation by yeast to obtain ethanol.The aim of this study is to examine the influence of substrateconcentration, temperature and pH upon enzymatic saccharification ofwaste cellulosic materials, based on office paper, newspaper andcardboard, in ratio of 1:1:1 (w/w and reducing sugar accumulationdynamics in optimised conditions. The study has established optimalparameters: the ratio of enzyme:substrate as 0.5 EU/g substrate,temperature 48°C, pH 4.8 and addition of surfactant Tween 80 inproportion of 0.3 %, reported to the total volume of liquid. The reducing sugar yield was 35 mg reducing sugars/ g dry weight cellulosic waste.

  16. PRELIMINARY FEASIBILITY ANALYSIS FOR AN INTEGRATED BIOMATERIALS AND ETHANOL BIOREFINERY USING WHEAT STRAW FEEDSTOCK

    OpenAIRE

    Leistritz, F. Larry; Senechal, Donald M.; Stowers, Mark D.; McDonald, William F.; Saffron, Chris M.; Hodur, Nancy M.

    2006-01-01

    Biobased products and fuels appear to have a very bright future. A consortium led by NDSU is currently engaged in a project that would use cellulose nanofibers derived from wheat straw to make a product that could substitute for fiberglass and plastics in many applications, including automotive parts. The work described here analyzes the economic value of producing cellulose nanowhiskers (CNW) as a co-product in an ethanol biorefinery. An ASPEN Plus-based process model was developed to evalua...

  17. SACCHARIFICATION BY FUNGI AND ETHANOL PRODUCTION BY BACTERIA USING LIGNOCELLULOSIC MATERIALS

    OpenAIRE

    Srivastava Ajeet Kumar; Agrawal Pushpa

    2012-01-01

    Lignocellulosic material is one of the most abundant, renewable and inexpensive energy resources for bioethanol production. These materials are mainly composed of three groups of polymers namely cellulose, hemicellulose and lignin. Cellulose and hemicellulose are sugar rich fractions of interest for use in fermentation processes such as ethanol production. Cellulase production by the different fungi like Trichoderma reesei (MTCC-4876), Phanerochaete chrysosporium (MTCC-787) and Aspergillus aw...

  18. Interactions of microfibrillated cellulose and cellulosic fines with cationic polyelectrolytes

    OpenAIRE

    Taipale, Tero

    2010-01-01

    The overall aim of this work was to produce and characterize different types of cellulosic fines and microfibrillated cellulose; to study their interactions with high molar mass cationic polyelectrolytes; and to demonstrate novel examples of their utilization. The work was performed, and its results discussed mainly from papermaking point of view, but the results are also well applicable in other fields of industry. Cellulosic fines are an essential component of papermaking fiber suspens...

  19. Nitrogen fertilization challenges the climate benefit of cellulosic biofuels

    Science.gov (United States)

    Ruan, Leilei; Bhardwaj, Ajay K.; Hamilton, Stephen K.; Robertson, G. Philip

    2016-06-01

    Cellulosic biofuels are intended to improve future energy and climate security. Nitrogen (N) fertilizer is commonly recommended to stimulate yields but can increase losses of the greenhouse gas nitrous oxide (N2O) and other forms of reactive N, including nitrate. We measured soil N2O emissions and nitrate leaching along a switchgrass (Panicum virgatum) high resolution N-fertilizer gradient for three years post-establishment. Results revealed an exponential increase in annual N2O emissions that each year became stronger (R 2 > 0.9, P strategy for fully realizing the climate benefits of cellulosic biofuel production.

  20. Wet oxidation pretreatment of rape straw for ethanol production

    International Nuclear Information System (INIS)

    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%.

  1. Evaluation of Potential Fungal Species for the in situ Simultaneous Saccharification and Fermentation (SSF) of Cellulosic Material

    OpenAIRE

    van Leeuwen, J.; Vincent, M; Pometto III, A. L.

    2011-01-01

    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 p...

  2. Ethanol: No Free Lunch

    OpenAIRE

    Schmitz Andrew; Moss Charles B.; Schmitz Troy G.

    2007-01-01

    The sharp rise in energy prices in the 1980s triggered a strong interest in the production of ethanol as an additional energy component. Economists are divided as to the payoffs from ethanol derived corn in part because of the complex interrelationship between energy produced from ethanol and energy from fossil fuels. Using a welfare economic framework, we calculate that there can be treasury savings from ethanol using tax credits as these subsidies can be smaller than direct payments to corn...

  3. Energy Integration by Fuel Ethanol Production

    Energy Technology Data Exchange (ETDEWEB)

    Frosterud, Daniel [Christian Berner AB, Partille (Sweden); Geest, Jan de [GEA Wiegand GmbH, Ettlingen (Germany)

    2006-07-15

    The presentation gives an overview of 3 different concepts for energy integration by fuel ethanol production; for a typical wheat and rye based bio ethanol plant, for the ethanol plants with corn as basic material, and for products on cellulose or sugar basis, such as sugar cane. For the latter, the Ecostill concept is presented, consisting of a combination of a mash evaporator heated by the rectification column.The differences between the rye and the corn based plants is in the temperature tolerance of the stillage, giving different options for energy integration. For the wheat, rye and corn based processes the stillage evaporation is explained, using an MVR driven pre-evaporator and a finisher on drier vapours. The ecostill concept for sugar and celloluse based feedstock is a combination of beer or molasses concentration in combination with ethanol rectification, without any drying of the vinasses. The rectifier supplies the energy for the evaporator. With the 3 vessel ethanol de-hydration system there is always a constant energy stream available which is re-used.Further more operational cost, investment and energy cost figures of a typical up to date 400,000 l/d Bio Ethanol plant on corn are given in the form of pies.These show how important it is the have a low energy consumption and how important it is to generate as much alcohol from the feed material as possible, since 1/2 of the operational cost of a corn based plant is the costs for the feedstock. (Full text of contribution)

  4. 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

  5. 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

  6. 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.

  7. Novel oil resistant cellulosic materials

    OpenAIRE

    Aulin, Christian

    2009-01-01

    The aim of this study has been to prepare and characterise oil resistant cellulosic materials, ranging from model surfaces to papers and aerogels. The cellulosic materials were made oil resistant by chemical and topographic modifications, based on surface energy, surface roughness and barrier approaches. Detailed wetting studies of the prepared cellulosic materials were made using contact angle measurements and standardised penetration tests with different alkanes and oil mixtures. A signific...

  8. Fermentative Conversion of Cellulose to Acetic Acid and Cellulolytic Enzyme Production by a Bacterial Mixed Culture Obtained from Sewage Sludge †

    OpenAIRE

    Khan, A. W.; Wall, Duncan; L. Van Den Berg

    1981-01-01

    A simple procedure that uses a cellulose-enriched culture started from sewage sludge was developed for producing cellulolytic enzymes and converting cellulose to acetic acid rather than CH4 and CO2. In this procedure, the culture which converts cellulose to CH4 and CO2 was mixed with a synthetic medium and cellulose and heated to 80°C for 15 min before incubation. The end products formed were acetic acid, propionic acid, CO2, and traces of ethanol and H2. Supernatants from 6- to 10-day-old cu...

  9. Cellulose biogenesis in Dictyostelium discoideum

    Energy Technology Data Exchange (ETDEWEB)

    Blanton, R.L.

    1993-12-31

    Organisms that synthesize cellulose can be found amongst the bacteria, protistans, fungi, and animals, but it is in plants that the importance of cellulose in function (as the major structural constituent of plant cell walls) and economic use (as wood and fiber) can be best appreciated. The structure of cellulose and its biosynthesis have been the subjects of intense investigation. One of the most important insights gained from these studies is that the synthesis of cellulose by living organisms involves much more than simply the polymerization of glucose into a (1{r_arrow}4)-{beta}-linked polymer. The number of glucoses in a polymer (the degree of polymerization), the crystalline form assumed by the glucan chains when they crystallize to form a microfibril, and the dimensions and orientation of the microfibrils are all subject to cellular control. Instead of cellulose biosynthesis, a more appropriate term might be cellulose biogenesis, to emphasize the involvement of cellular structures and mechanisms in controlling polymerization and directing crystallization and deposition. Dictyostelium discoideum is uniquely suitable for the study of cellulose biogenesis because of its amenability to experimental study and manipulation and the extent of our knowledge of its basic cellular mechanisms (as will be evident from the rest of this volume). In this chapter, I will summarize what is known about cellulose biogenesis in D. discoideum, emphasizing its potential to illuminate our understanding both of D. discoideum development and plant cellulose biogenesis.

  10. Bioconversion of sugarcane biomass into ethanol: an overview about composition, pretreatment methods, detoxification of hydrolysates, enzymatic saccharification, and ethanol fermentation.

    Science.gov (United States)

    Canilha, Larissa; Kumar Chandel, Anuj; dos Santos Milessi, Thais Suzane; Fernandes Antunes, Felipe Antônio; da Costa Freitas, Wagner Luiz; das Graças Almeida Felipe, Maria; da Silva, Silvio Silvério

    2012-01-01

    Depleted supplies of fossil fuel, regular price hikes of gasoline, and environmental damage have necessitated the search for economic and eco-benign alternative of gasoline. Ethanol is produced from food/feed-based substrates (grains, sugars, and molasses), and its application as an energy source does not seem fit for long term due to the increasing fuel, food, feed, and other needs. These concerns have enforced to explore the alternative means of cost competitive and sustainable supply of biofuel. Sugarcane residues, sugarcane bagasse (SB), and straw (SS) could be the ideal feedstock for the second-generation (2G) ethanol production. These raw materials are rich in carbohydrates and renewable and do not compete with food/feed demands. However, the efficient bioconversion of SB/SS (efficient pretreatment technology, depolymerization of cellulose, and fermentation of released sugars) remains challenging to commercialize the cellulosic ethanol. Among the technological challenges, robust pretreatment and development of efficient bioconversion process (implicating suitable ethanol producing strains converting pentose and hexose sugars) have a key role to play. This paper aims to review the compositional profile of SB and SS, pretreatment methods of cane biomass, detoxification methods for the purification of hydrolysates, enzymatic hydrolysis, and the fermentation of released sugars for ethanol production. PMID:23251086

  11. Microbial fuel cell treatment of ethanol fermentation process water

    Science.gov (United States)

    Borole, Abhijeet P.

    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.

  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...... by cellulases more than three times compared to the untreated control. During this wet oxidation, 51.7% of the hemicellulose and 58.3% of the lignin were solubilized, whereas 87.1% of the cellulose remained in the solids. After enzymatic hydrolysis of pretreated fibers from the same treatment, the...

  13. Enzymatic degradation of plutonium-contaminated cellulose products

    Energy Technology Data Exchange (ETDEWEB)

    Heintz, C.E.; Rainwater, K.A.; Swift, L.M. [Texas Tech Univ., Lubbock, TX (United States); Barnes, D.L. [Amarillo National Resource Center for Plutonium, TX (United States); Worl, L.; Avens, L. [Los Alamos National Lab., NM (United States)

    1999-03-01

    Enzyme solutions produced for commercial purposes unrelated to waste management have the potential for reducing the volume of wastes in streams containing cellulose, lipid and protein materials. For example, the authors have shown that cellulases used in denim production and in detergent formulations are able to digest cellulose-containing sorbents and other cellulose-based wastes contaminated either with crude oil or with radionuclides. This presentation describes the use of one such enzyme preparation (Rapidase{trademark}) for the degradation of cotton sorbents intentionally contaminated with low levels of plutonium. This is part of a feasibility study to determine if such treatments have a role in reducing the volume of low level and transuranic wastes to minimize the amount of radionuclide-contaminated waste that must be disposed of in secured storage areas.

  14. Enzymatic degradation of plutonium-contaminated cellulose products

    International Nuclear Information System (INIS)

    Enzyme solutions produced for commercial purposes unrelated to waste management have the potential for reducing the volume of wastes in streams containing cellulose, lipid and protein materials. For example, the authors have shown that cellulases used in denim production and in detergent formulations are able to digest cellulose-containing sorbents and other cellulose-based wastes contaminated either with crude oil or with radionuclides. This presentation describes the use of one such enzyme preparation (Rapidase trademark) for the degradation of cotton sorbents intentionally contaminated with low levels of plutonium. This is part of a feasibility study to determine if such treatments have a role in reducing the volume of low level and transuranic wastes to minimize the amount of radionuclide-contaminated waste that must be disposed of in secured storage areas

  15. 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

  16. Ethanol production from Eucalyptus plantation thinnings.

    Science.gov (United States)

    McIntosh, S; Vancov, T; Palmer, J; Spain, M

    2012-04-01

    Conditions for optimal pretreatment of eucalypt (Eucalyptus dunnii) and spotted gum (Corymbia citriodora) forestry thinning residues for bioethanol production were empirically determined using a 3(3) factorial design. Up to 161mg/g xylose (93% theoretical) was achieved at moderate combined severity factors (CSF) of 1.0-1.6. At CSF>2.0, xylose levels declined, owing to degradation. Moreover at high CSF, depolymerisation of cellulose was evident and corresponded to glucose (155mg/g, ∼33% cellulose) recovery in prehydrolysate. Likewise, efficient saccharification with Cellic® CTec 2 cellulase correlated well with increasing process severity. The best condition yielded 74% of the theoretical conversion and was attained at the height of severity (CSF of 2.48). Saccharomyces cerevisiae efficiently fermented crude E. dunnii hydrolysate within 30h, yielding 18g/L ethanol, representing a glucose to ethanol conversion rate of 0.475g/g (92%). Based on our findings, eucalyptus forest thinnings represent a potential feedstock option for the emerging Australian biofuel industry. PMID:22342086

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

    International Nuclear Information System (INIS)

    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)

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

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, Barry D.; Johnson, Nicholas H. [Environmental Policy Program, Department of Social Sciences, Michigan Technological University, Houghton, MI 49931-1295 (United States)

    2009-05-15

    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)

  19. Ethanol production of banana shell and cassava starch

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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)

  1. TEMPO-oxidized cellulose nanofibers

    Science.gov (United States)

    Isogai, Akira; Saito, Tsuguyuki; Fukuzumi, Hayaka

    2011-01-01

    Native wood celluloses can be converted to individual nanofibers 3-4 nm wide that are at least several microns in length, i.e. with aspect ratios >100, by TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation and successive mild disintegration in water. Preparation methods and fundamental characteristics of TEMPO-oxidized cellulose nanofibers (TOCN) are reviewed in this paper. Significant amounts of C6 carboxylate groups are selectively formed on each cellulose microfibril surface by TEMPO-mediated oxidation without any changes to the original crystallinity (~74%) or crystal width of wood celluloses. Electrostatic repulsion and/or osmotic effects working between anionically-charged cellulose microfibrils, the ζ-potentials of which are approximately -75 mV in water, cause the formation of completely individualized TOCN dispersed in water by gentle mechanical disintegration treatment of TEMPO-oxidized wood cellulose fibers. Self-standing TOCN films are transparent and flexible, with high tensile strengths of 200-300 MPa and elastic moduli of 6-7 GPa. Moreover, TOCN-coated poly(lactic acid) films have extremely low oxygen permeability. The new cellulose-based nanofibers formed by size reduction process of native cellulose fibers by TEMPO-mediated oxidation have potential application as environmentally friendly and new bio-based nanomaterials in high-tech fields.

  2. Ultrasonic dyeing of cellulose nanofibers.

    Science.gov (United States)

    Khatri, Muzamil; Ahmed, Farooq; Jatoi, Abdul Wahab; Mahar, Rasool Bux; Khatri, Zeeshan; Kim, Ick Soo

    2016-07-01

    Textile dyeing assisted by ultrasonic energy has attained a greater interest in recent years. We report ultrasonic dyeing of nanofibers for the very first time. We chose cellulose nanofibers and dyed with two reactive dyes, CI reactive black 5 and CI reactive red 195. The cellulose nanofibers were prepared by electrospinning of cellulose acetate (CA) followed by deacetylation. The FTIR results confirmed complete conversion of CA into cellulose nanofibers. Dyeing parameters optimized were dyeing temperature, dyeing time and dye concentrations for each class of the dye used. Results revealed that the ultrasonic dyeing produced higher color yield (K/S values) than the conventional dyeing. The color fastness test results depicted good dye fixation. SEM analysis evidenced that ultrasonic energy during dyeing do not affect surface morphology of nanofibers. The results conclude successful dyeing of cellulose nanofibers using ultrasonic energy with better color yield and color fastness results than conventional dyeing. PMID:26964959

  3. 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.

  4. Cellulose aerogels prepared from an aqueous zinc chloride salt hydrate melt.

    Science.gov (United States)

    Schestakow, Maria; Karadagli, Ilknur; Ratke, Lorenz

    2016-02-10

    Monolithic cellulose aerogels are prepared using a salt hydrate melt based on cheap zinc chloride tetrahydrate (ZnCl2·4H2O) that can be washed out of the wet gel-body by using common solvents such as water, ethanol, isopropanol or acetone. Cellulose aerogels with concentrations of 1-5 wt.% cellulose were produced. These aerogels are characterized with respect to shrinkage, density and surface area as well as mechanical properties and micro-structure via SEM. Cellulose aerogels regenerated in acetone show a specific surface area of around 340 m(2)g(-1) being 60% higher than those regenerated in water. The onset of irreversible plastic deformation under compressive load is around 0.8 MPa for acetone-regenerated aerogels and thus a factor of two larger compared to ethanol regenerated ones. The Young's modulus depends almost linearly on the cellulose concentration which is observed for all regenerative fluids with the exception of water. The results achieved are presented in light of the polarity and ability of solvation of ZnCl2·4H2O in the regenerative fluids used. PMID:26686174

  5. Ethanol and neuronal metabolism.

    Science.gov (United States)

    Mandel, P; Ledig, M; M'Paria, J R

    1980-01-01

    The effect of ethanol on membrane enzymes (Na+, K+ and Mg2+ ATPases, 5'-nucleotidase, adenylate cyclase) alcohol dehydrogenase, aldehyde dehydrogenase and superoxide dismutase were studied in nerve cells (established cell lines, primary cultures of chick and rat brain) cultured in the presence of 100 mM ethanol, and in total rat brain, following various ethanol treatments of the rats (20% ethanol as the sole liquid source, intraperitoneal injection). The results show a difference between neuronal and glial cells. Most of the observed changes in enzymatic activities returned rapidly to control values when ethanol was withdrawn from the culture medium or from the diet. Alcohol dehydrogenase was more stimulated by ethanol than aldehyde dehydrogenase; therefore acetaldehyde may be accumulated. The inhibition of superoxide dismutase activity may allow an accumulation of cytotoxic O2- radicals in nervous tissue and may explain the polymorphism of lesions brought about by alcohol intoxication. PMID:6264495

  6. Fermentation method producing ethanol

    Science.gov (United States)

    Wang, Daniel I. C.; Dalal, Rajen

    1986-01-01

    Ethanol is the major end product of an anaerobic, thermophilic fermentation process using a mutant strain of bacterium Clostridium thermosaccharolyticum. This organism is capable of converting hexose and pentose carbohydrates to ethanol, acetic and lactic acids. Mutants of Clostridium thermosaccharolyticum are capable of converting these substrates to ethanol in exceptionally high yield and with increased productivity. Both the mutant organism and the technique for its isolation are provided.

  7. 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

  8. Integrated production of cellulosic bioethanol and succinic acid from industrial hemp in a biorefinery concept

    DEFF Research Database (Denmark)

    Kuglarz, Mariusz; Alvarado-Morales, Merlin; Karakashev, Dimitar Borisov;

    2016-01-01

    The aim of this study was to develop integrated biofuel (cellulosic bioethanol) and biochemical (succinic acid) production from industrial hemp (Cannabis sativa L.) in a biorefinery concept. Two types of pretreatments were studied (dilute-acid and alkaline oxidative method). High cellulose recovery...... (> 95%) as well as significant hemicelluloses solubilization (49-59%) after acid-based method and lignin solubilization (35-41%) after alkaline H2O2 method were registered. Alkaline pretreatment showed to be superior over the acid-based method with respect to the rate of enzymatic hydrolysis and ethanol...

  9. Cellulose Derivatives for Water Repellent Properties

    Science.gov (United States)

    In this poster presentation, we will discuss the synthesis and structural characterizations of nitro-benzyl cellulose (1), amino-benzyl cellulose (2) and pentafluoro –benzyl cellulose (3). All cellulose derivatives are synthesized by etherification process in lithium chloride/N,N-dimethylacetamide h...

  10. Cellulose nanocrystals: synthesis, functional properties, and applications

    OpenAIRE

    George J.; Sabapathi SN

    2015-01-01

    Johnsy George, SN Sabapathi Food Engineering and Packaging Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, India Abstract: Cellulose nanocrystals are unique nanomaterials derived from the most abundant and almost inexhaustible natural polymer, cellulose. These nanomaterials have received significant interest due to their mechanical, optical, chemical, and rheological properties. Cellulose nanocrystals primarily obtained from naturally occurring cellulose fibers...

  11. Cellulose synthase complexes: structure and regulation

    Directory of Open Access Journals (Sweden)

    Lei eLei

    2012-04-01

    Full Text Available This review is to update the most recent progress on characterization of the composition, regulation, and trafficking of cellulose synthase complexes. We will highlight proteins that interact with cellulose synthases, e.g. cellulose synthase-interactive protein 1 (CSI1. The potential regulation mechanisms by which cellulose synthase interact with cortical microtubules in primary cell walls will be discussed.

  12. Pharmaceutical significance of cellulose: A review

    Directory of Open Access Journals (Sweden)

    2008-11-01

    Full Text Available The amalgamation of polymer and pharmaceutical sciences led to the introduction of polymer in the design and development of drug delivery systems. Polymeric delivery systems are mainly intended to achieve controlled or sustained drug delivery. Polysaccharides fabricated into hydrophilic matrices remain popular biomaterials for controlled-release dosage forms and the most abundant naturally occurring biopolymer is cellulose; so hdroxypropylmethyl cellulose, hydroxypropyl cellulose, microcrystalline cellulose and hydroxyethyl cellulose can be used for production of time controlled delivery systems. Additionally microcrystalline cellulose, sodium carboxymethyl cellulose, hydroxypropylmethyl cellulose, hydroxyethyl cellulose as well as hydroxypropyl cellulose are used to coat tablets. Cellulose acetate phthalate and hydroxymethyl cellulose phthalate are also used for enteric coating of tablets. Targeting of drugs to the colon following oral administration has also been accomplished by using polysaccharides such as hdroxypropylmethyl cellulose and hydroxypropyl cellulose in hydrated form; also they act as binders that swell when hydrated by gastric media and delay absorption. This paper assembles the current knowledge on the structure and chemistry of cellulose, and in the development of innovative cellulose esters and ethers for pharmaceuticals.

  13. Radiation degradation of cellulose

    International Nuclear Information System (INIS)

    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. 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 of...

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

    International Nuclear Information System (INIS)

    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.

  16. 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....

  17. Composition and ethanol production potential of cotton gin residues.

    Science.gov (United States)

    Agblevor, Foster A; Batz, Sandra; Trumbo, Jessica

    2003-01-01

    Cotton gin residue (CGR) collected from five cotton gins was fractionated and characterized for summative composition. The major fractions of the CGR varied widely between cotton gins and consisted of clean lint (5-12%),hulls (16-48%), seeds (6-24%), motes (16-24%), and leaves (14-30%). The summative composition varied within and between cotton gins and consisted of ash (7.9-14.6%), acid-insoluble material (18-26%), xylan (4-15%),and cellulose (20-38%). Overlimed steam-exploded cotton gin waste was readily fermented to ethanol by Escherichia coli KO11. Ethanol yields were feedstock and severity dependent and ranged from 58 to 92.5% of the theoretical yields. The highest ethanol yield was 191 L (50 gal)/t, and the lowest was 120 L (32 gal)/t. PMID:12721487

  18. BIOCONVERSION OF WATER HYACINTH HYDROLYSATE INTO ETHANOL

    Directory of Open Access Journals (Sweden)

    Sunita Bandopadhyay Mukhopadhyay

    2010-04-01

    Full Text Available The fast growing aquatic weed water hyacinth, which is available almost year-round in the tropics and subtropics, was utilized as the chief source of cellulose for production of fuel ethanol via enzymatic hydrolysis and fermentation. Fungal cellulases produced on-site by utilizing acid-alkali pretreated water hyacinth as the substrate were used as the crude enzyme source for hydrolysis of identically pretreated biomass. Four different modes of enzymatic hydrolysis and fermentation were trialed in the present study for optimization of the yield of ethanol. Two common yeasts viz., Saccharomyces cerevisiae and Pachysolen tannophilus, were used for fermentation of hexose and pentose sugars in the hydrolysate. Significant enhancement of concentration (8.3 g/L and yield (0.21 g/g of ethanol was obtained through a prefermentation hydrolysis-simultaneous saccharification and fermentation (PH-SSF process, over the other three processes viz., separate hydrolysis and fermentation (SHF, simultaneous saccharification and fermentation (SSF, and single batch bioconversion (SBB by utilizing fungal culture broth with and without filtration as crude enzyme source.

  19. 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.

  20. Market penetration of ethanol

    International Nuclear Information System (INIS)

    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)

  1. Thermophilic Gram-Positive Biocatalysts for Biomass Conversion to Ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Shanmugam, K.T.; Ingram, L.O.; Maupin-Furlow, J.A.; Preston, J.F.; Aldrich, H.C.

    2003-12-01

    Production of energy from renewable sources is receiving increased attention due to the finite nature of fossil fuels and the environmental impact associated with the continued large scale use of fossil energy sources. Biomass, a CO2-neutral abundant resource, is an attractive alternate source of energy. Biomass-derived sugars, such as glucose, xylose, and other minor sugars, can be readily fermented to fuel ethanol and commodity chemicals. Extracellular cellulases produced by fungi are commercially developed for depolymerization of cellulose in biomass to glucose for fermentation by appropriate biocatalysts in a simultaneous saccharification and fermentation (SSF) process. Due to the differences in the optimum conditions for the activity of the fungal cellulases and the growth and fermentation characteristics of the current industrial biocatalysts, SSF of cellulose is envisioned at conditions that are not optimal for the fungal cellulase activity leading to higher than required cost of cellulase in SSF. We have isolated bacterial biocatalysts whose growth and fermentation requirements match the optimum conditions for commercial fungal cellulase activity (pH 5.0 and 50 deg. C). These isolates fermented both glucose and xylose, major components of cellulose and hemicellulose, respectively, to L(+)-lactic acid. Xylose was metabolized through the pentose-phosphate pathway by these organisms as evidenced by the fermentation profile and analysis of the fermentation products of 13C1-xylose by NMR. As expected for the metabolism of xylose by the pentose-phosphate pathway, 13C-lactate accounted for more than 90% of the total 13C-labeled products. All three strains fermented crystalline cellulose to lactic acid with the addition of fungal cellulase (Spezyme CE) (SSF) at an optimum of about 10 FPU/g cellulose. These isolates also fermented cellulose and sugar cane bagasse hemicellulose acid hydrolysate simultaneously. Based on fatty acid profile and 16S rRNA sequence, these

  2. Increasing cellulose production and transgenic plant growth in forest tree species

    Institute of Scientific and Technical Information of China (English)

    TANG Wei; Aaron Nelson; Emmanuel Johnson

    2005-01-01

    Cellulose is one of many important polymers in plants. Cellulose is made of repeat units of the monomer glucose. Cellulose is a major industrial biopolymer in the forest products, textile, and chemical industries. It also forms a large portion of the biomass useful in the generation of energy. Moreover, cellulose-based biomass is a renewable energy source that can be used for the generation of ethanol as a fuel. Cellulose is synthesized by a variety of living organisms such as plants and algae. It is the major component of plant cell walls with secondary cell walls having a much higher content of cellulose. The relationship between cellulose and lignin biosynthesis is complicated, but it is confirmed that inhibition of lignin biosynthesis in transgenic trees will increase cellulose biosynthesis and plant growth. Cellulose accumulation may be increased by down-regulating 4-coumarate:coenzyme A ligase (4CL, EC 6.2.1.12) as shown in transgenic aspen. There is no similar reports on down-regulating 4CL in transgenic conifers. Based on our established Agrobacterium tumefaciens-mediated transformation system in loblolly pine, we are able to produce antisense 4-CL transgenic loblolly pine which is predicted to have increasing cellulose accumulation. The overall objective of this project is to genetically engineer forest tree species such as loblolly pine with reduced amount of lignin and increased cellulose content. The research strategy includes: (1) isolate the 4-coumarate:coenzyme A ligase gene from loblolly pine seedlings by reverse transcription-polymerase chain reaction (RT-PCR) and Rapid Amplification of cDNA Ends-Polymerase Chain Reaction (RACE-PCR) techniques from the cDNA library; (2) construct binary expression vectors with antisense 4CL coding sequences and introduce antisense constructs of the 4-coumarate:coenzyme A ligase gene cloned from loblolly pine into the loblolly pine to down regulate the 4-coumarate:coenzyme A ligase gene expression; (3) study the

  3. Characterization of Cellulose Synthesis in Plant Cells

    OpenAIRE

    Samaneh Sadat Maleki; Kourosh Mohammadi; Kong-shu Ji

    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...

  4. The sustainability of ethanol production from sugarcane

    International Nuclear Information System (INIS)

    The rapid expansion of ethanol production from sugarcane in Brazil has raised a number of questions regarding its negative consequences and sustainability. Positive impacts are the elimination of lead compounds from gasoline and the reduction of noxious emissions. There is also the reduction of CO2 emissions, since sugarcane ethanol requires only a small amount of fossil fuels for its production, being thus a renewable fuel. These positive impacts are particularly noticeable in the air quality improvement of metropolitan areas but also in rural areas where mechanized harvesting of green cane is being introduced, eliminating the burning of sugarcane. Negative impacts such as future large-scale ethanol production from sugarcane might lead to the destruction or damage of high-biodiversity areas, deforestation, degradation or damaging of soils through the use of chemicals and soil decarbonization, water resources contamination or depletion, competition between food and fuel production decreasing food security and a worsening of labor conditions on the fields. These questions are discussed here, with the purpose of clarifying the sustainability aspects of ethanol production from sugarcane mainly in Sao Paulo State, where more than 60% of Brazil's sugarcane plantations are located and are responsible for 62% of ethanol production. (author)

  5. The sustainability of ethanol production from sugarcane

    International Nuclear Information System (INIS)

    The rapid expansion of ethanol production from sugarcane in Brazil has raised a number of questions regarding its negative consequences and sustainability. Positive impacts are the elimination of lead compounds from gasoline and the reduction of noxious emissions. There is also the reduction of CO2 emissions, since sugarcane ethanol requires only a small amount of fossil fuels for its production, being thus a renewable fuel. These positive impacts are particularly noticeable in the air quality improvement of metropolitan areas but also in rural areas where mechanized harvesting of green cane is being introduced, eliminating the burning of sugarcane. Negative impacts such as future large-scale ethanol production from sugarcane might lead to the destruction or damage of high-biodiversity areas, deforestation, degradation or damaging of soils through the use of chemicals and soil decarbonization, water resources contamination or depletion, competition between food and fuel production decreasing food security and a worsening of labor conditions on the fields. These questions are discussed here, with the purpose of clarifying the sustainability aspects of ethanol production from sugarcane mainly in Sao Paulo State, where more than 60% of Brazil's sugarcane plantations are located and are responsible for 62% of ethanol production

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

    International Nuclear Information System (INIS)

    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)

  7. 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. PMID:23318834

  8. Utilization of Soft Wood Wastes as a Feed Stock to Produce Fuel Ethanol

    Directory of Open Access Journals (Sweden)

    Adnan M. Khalil

    2009-01-01

    Full Text Available Problem statement: The current research investigated the utilization of soft wood waste as a feedstock to produce a value-added product-fuel ethanol. Approach: The main issue in converting soft wood waste to fuel ethanol is the accessibility of the polysaccharides for breaking down into monosaccharides. This study focused on the use of steam as the pretreatment method. The governing factors for the effectiveness of steam pretreatment are steam temperature and retention times. Following steam pretreatment, soft wood waste was subjected to acid hydrolysis. The sugars released by acid hydrolysis were fermented in series chemical reactions that convert sugars to ethanol. The fermentation reaction was caused by yeast, which feed on the sugars. Results: Steam pretreatment was able to improve both glucose yields from acid hydrolysis and ethanol yields from fermentation. The results obtained from this study showed that steam pretreated soft wood waste are a heterogeneous material. So biomass goes through a size-reduction step to make it easier to handle and to make the ethanol production process more efficient. Steam treatment on soft wood waste increased the hydrolysis of cellulose by acid hydrolysis. Following 24 h of diluted or concentrated acid hydrolysis, a maximum cellulose conversion of 20.5% was obtained. Similarly, sugars to ethanol conversions were improved by steam treatment. Maximum sugar to ethanol conversion of 40.7% was observed. Conclusion: It was recommended that the hydrolysis process be done for 40 min to obtain the maximum sugars yield in a reasonable period of time.

  9. Observational constraints on the global atmospheric budget of ethanol

    Directory of Open Access Journals (Sweden)

    V. Naik

    2010-06-01

    Full Text Available Energy security and climate change concerns have led to the promotion of biomass-derived ethanol, an oxygenated volatile organic compound (OVOC, as a substitute for fossil fuels. Although ethanol is ubiquitous in the troposphere, our knowledge of its current atmospheric budget and distribution is limited. Here, for the first time we use a global chemical transport model in conjunction with atmospheric observations to place constraints on the ethanol budget, noting that additional measurements of ethanol (and its precursors are still needed to enhance confidence in our estimated budget. Global sources of ethanol in the model include 5.0 Tg yr−1 from industrial sources and biofuels, 9.2 Tg yr−1 from terrestrial plants, ~0.5 Tg yr−1 from biomass burning, and 0.05 Tg yr−1 from atmospheric reactions of the ethyl peroxy radical (C2H5O2 with itself and with the methyl peroxy radical (CH3O2. The resulting atmospheric lifetime of ethanol in the model is 2.8 days. Gas-phase oxidation by the hydroxyl radical (OH is the primary global sink of ethanol in the model (65%, followed by dry deposition (25%, and wet deposition (10%. Over continental areas, ethanol concentrations predominantly reflect direct anthropogenic and biogenic emission sources. Uncertainty in the biogenic ethanol emissions, estimated at a factor of three, may contribute to the 50% model underestimate of observations in the North American boundary layer. Current levels of ethanol measured in remote regions are an order of magnitude larger than those in the model, suggesting a major gap in understanding. Stronger constraints on the budget and distribution of ethanol and OVOCs are a critical step towards assessing the impacts of increasing the use of ethanol as a fuel.

  10. Canada's ethanol retail directory

    International Nuclear Information System (INIS)

    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

  11. Canadian ethanol retailers' directory

    International Nuclear Information System (INIS)

    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

  12. Water dispersible microbicidal cellulose acetate phthalate film

    Directory of Open Access Journals (Sweden)

    Li Yun-Yao

    2003-11-01

    Full Text Available Abstract Background Cellulose acetate phthalate (CAP has been used for several decades in the pharmaceutical industry for enteric film coating of oral tablets and capsules. Micronized CAP, available commercially as "Aquateric" and containing additional ingredients required for micronization, used for tablet coating from water dispersions, was shown to adsorb and inactivate the human immunodeficiency virus (HIV-1, herpesviruses (HSV and other sexually transmitted disease (STD pathogens. Earlier studies indicate that a gel formulation of micronized CAP has a potential as a topical microbicide for prevention of STDs including the acquired immunodeficiency syndrome (AIDS. The objective of endeavors described here was to develop a water dispersible CAP film amenable to inexpensive industrial mass production. Methods CAP and hydroxypropyl cellulose (HPC were dissolved in different organic solvent mixtures, poured into dishes, and the solvents evaporated. Graded quantities of a resulting selected film were mixed for 5 min at 37°C with HIV-1, HSV and other STD pathogens, respectively. Residual infectivity of the treated viruses and bacteria was determined. Results The prerequisites for producing CAP films which are soft, flexible and dispersible in water, resulting in smooth gels, are combining CAP with HPC (other cellulose derivatives are unsuitable, and casting from organic solvent mixtures containing ≈50 to ≈65% ethanol (EtOH. The films are ≈100 µ thick and have a textured surface with alternating protrusions and depressions revealed by scanning electron microscopy. The films, before complete conversion into a gel, rapidly inactivated HIV-1 and HSV and reduced the infectivity of non-viral STD pathogens >1,000-fold. Conclusions Soft pliable CAP-HPC composite films can be generated by casting from organic solvent mixtures containing EtOH. The films rapidly reduce the infectivity of several STD pathogens, including HIV-1. They are converted into

  13. Chromophores in lignin-free cellulosic materials belong to three compound classes. Chromophores in cellulosics, XII

    Science.gov (United States)

    The CRI (chromophore release and identification) method isolates well-defined chromophoric substances from different cellulosic matrices, such as highly bleached pulps, cotton linters, bacterial cellulose, viscose or lyocell fibers, and cellulose acetates. The chromophores are present only in extrem...

  14. Bacterial cellulose/boehmite composites

    Energy Technology Data Exchange (ETDEWEB)

    Salvi, Denise T.B. de; Barud, Hernane S.; Messaddeq, Younes; Ribeiro, Sidney J.L. [Universidade Estadual Paulista Julio de Mesquita Filho. UNESP. Instituto de Quimica de Araraquara, SP (Brazil); Caiut, Jose Mauricio A. [Universidade de Sao Paulo. Departamento de Quimica - FFCLRP/USP, Ribeirao Preto, SP (Brazil)

    2011-07-01

    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)

  15. Bacterial cellulose/boehmite composites

    International Nuclear Information System (INIS)

    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)

  16. 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.

  17. 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.

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

    International Nuclear Information System (INIS)

    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 CaCO3 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 Mg2+ 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.

  19. Cellulose biosynthesis in Acetobacter xylinum

    International Nuclear Information System (INIS)

    Time-lapse video microscopy has shown periodic reversals during the synthesis of cellulose. In the presence of Congo Red, Acetobacter produces a band of fine fibrils. The direction of cell movement is perpendicular to the longitudinal axis of cell, and the rate of movement was decreased. A linear row of particles, presumably the cellulose synthesizing complexes, was found on the outer membrane by freeze-fracture technique. During the cell cycle, the increase of particles in linear row, the differentiation to four linear rows and the separation of the linear rows have been observed. A digitonin-solubilized cellulose synthase was prepared from A. xylinum, and incubated under conditions known to lead to active in vitro synthesis of 1,4-β-D-glucan polymer. Electron microscopy revealed that clusters of fibrils were assembled within minutes. Individual fibrils are 17 ± 2 angstroms in diameter. Evidence for the cellulosic composition of newly synthesized fibrils was based on incorporation of tritium from UDP-[3H] glucose binding of gold-labeled cellobiohydrolase, and an electron diffraction pattern identified as cellulose II polymorph instead of cellulose I

  20. 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.

  1. Ethanol Demand in United States Regional Production of Oxygenate-limited Gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Hadder, G.R.

    2000-08-01

    The Energy Policy Act of 1992 (the Act) outlined a national energy strategy that called for reducing the nation's dependency on petroleum imports. The Act directed the Secretary of Energy to establish a program to promote and expand the use of renewable fuels. The Office of Transportation Technologies (OTT) within the U.S. Department of Energy (DOE) has evaluated a wide range of potential fuels and has concluded that cellulosic ethanol is one of the most promising near-term prospects. Ethanol is widely recognized as a clean fuel that helps reduce emissions of toxic air pollutants. Furthermore, cellulosic ethanol produces less greenhouse gas emissions than gasoline or any of the other alternative transportation fuels being considered by DOE.

  2. 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

    2016-01-01

    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. PMID:26837707

  3. 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.

  4. Influence of Culture Conditions and Medium Composition on the Production of Cellulose by Shiga Toxin-Producing Escherichia coli Cells ▿

    OpenAIRE

    Yoo, Byong Kwon; Chen, Jinru

    2009-01-01

    Culture conditions favoring cellulose production by Shiga toxin-producing Escherichia coli included a 28°C incubation temperature, an aerobic atmosphere, and the presence of 2% ethanol in Luria-Bertani no-salt agar with pH 6.0 and a water activity of 0.99. These findings will assist in formulating microbiological media useful for cellulose and biofilm research.

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

    Science.gov (United States)

    de Dicastillo, Carol López; Navarro, Rosa; Guarda, Abel; Galotto, Maria José

    2015-01-01

    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 (2,2'-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. PMID:26783842

  6. 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.

  7. Enzymatic Cellulose Hydrolysis: Enzyme Reusability and Visualization of beta-Glucosidase Immobilized in Calcium Alginate

    DEFF Research Database (Denmark)

    Tsai, Chien Tai; Meyer, Anne S.

    2014-01-01

    The high cellulase enzyme dosages required for hydrolysis of cellulose is a major cost challenge in lignocellulosic ethanol production. One method to decrease the enzyme dosage and increase biocatalytic productivity is to re-use beta-glucosidase (BG) via immobilization. In the present research, g...... by one round of enzymatic hydrolysis of hydrothermally pretreated barley straw during a 72 h reaction with immobilized BG and free BG.......The high cellulase enzyme dosages required for hydrolysis of cellulose is a major cost challenge in lignocellulosic ethanol production. One method to decrease the enzyme dosage and increase biocatalytic productivity is to re-use beta-glucosidase (BG) via immobilization. In the present research...... BG were recycled for cellulase catalyzed hydrolysis of Avicel. No significant loss in BG activity was observed for up to 20 rounds of reaction recycle steps of the BG particles of 48 h each, verifying a significant stabilization of the BG by immobilization. Similar high glucose yields were obtained...

  8. A thermodynamic investigation of the cellulose allomorphs: Cellulose(am), cellulose Iβ(cr), cellulose II(cr), and cellulose III(cr)

    International Nuclear Information System (INIS)

    Highlights: • Cellulose allomorphs were prepared and carefully characterized. • Measurements by oxygen bomb calorimetry, solution calorimetry, and by PPMS. • Thermodynamic properties for interconversion reactions of the cellulose allomorphs. • Review of the earlier literature with recalculation of property values. • Standard thermodynamic formation properties. - Abstract: The thermochemistry of samples of amorphous cellulose, cellulose I, cellulose II, and cellulose III was studied by using oxygen bomb calorimetry, solution calorimetry in which the solvent was cadoxen (a cadmium ethylenediamine solvent), and with a Physical Property Measurement System (PPMS) in zero magnetic field to measure standard massic heat capacities Cp,w∘ over the temperature range T = (2 to 302) K. The samples used in this study were prepared so as to have different values of crystallinity indexes CI and were characterized by X-ray diffraction, by Karl Fischer moisture determination, and by using gel permeation chromatography to determine the weight average degree of polymerization DPw. NMR measurements on solutions containing the samples dissolved in cadoxen were also performed in an attempt to resolve the issue of the equivalency or non-equivalency of the nuclei in the different forms of cellulose that were dissolved in cadoxen. While large differences in the NMR spectra for the various cellulose samples in cadoxen were not observed, one cannot be absolutely certain that these cellulose samples are chemically equivalent in cadoxen. Equations were derived which allow one to adjust measured property values of cellulose samples having a mass fraction of water wH2O to a reference value of the mass fraction of water wref. The measured thermodynamic properties (standard massic enthalpy of combustion ΔcHw∘, standard massic enthalpy of solution ΔsolHw∘, and Cp,w∘) were used in conjunction with the measured CI values to calculate values of the changes in the standard massic

  9. Alternative security

    International Nuclear Information System (INIS)

    This book contains the following chapters: The Military and Alternative Security: New Missions for Stable Conventional Security; Technology and Alternative Security: A Cherished Myth Expires; Law and Alternative Security: Toward a Just World Peace; Politics and Alternative Security: Toward a More Democratic, Therefore More Peaceful, World; Economics and Alternative Security: Toward a Peacekeeping International Economy; Psychology and Alternative Security: Needs, Perceptions, and Misperceptions; Religion and Alternative Security: A Prophetic Vision; and Toward Post-Nuclear Global Security: An Overview

  10. Estimating the net energy value of corn-ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Shapouri, H.; Duffield, J. [Department of Agriculture, Washington, DC (United States); Graboski, M.S. [Colorado School of Mines, Golden, CO (United States)

    1995-11-01

    Potential air quality benefits and a desire to improve domestic energy security has prompted researchers to investigate the net energy value (NEV) of corn-ethanol. Studies have been conducted in recent years in an attempt to quantify the energy used in growing and converting corn to ethanol. However, variations in data and assumptions among the studies have resulted in a wide range of NEV estimates. The purpose of this study is to identify the factors causing this wide variation and to develop a more consistent NEV estimate. We conclude that the NEV of corn-ethanol is positive when fertilizers are produced by modern processing plants, corn is converted in modern ethanol facilities, farmers achieve normal corn yields and energy credits are allocated to basic coproducts. Our estimate of 16,193 BTU/gal can be considered conservative, since it does not include energy credits for those plants that sell carbon dioxide. Corn ethanol is energy efficient as indicated by an energy ratio of 1.24, i.e., for every BTU dedicated to producing ethanol there is a 24 percent energy gain. Moreover, producing ethanol from domestic corn stocks achieves a net gain in a more desirable form of energy. Ethanol production utilizes abundant domestic feedstocks of coal and natural gas to convert corn into a premium liquid fuel that can replace petroleum imports by a factor of 7 to 1.

  11. Competitiveness of Brazilian Sugarcane Ethanol Compared to US Corn Ethanol

    OpenAIRE

    Crago, Christine Lasco; 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 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 this competitiveness and compares the greenhouse gas intensity of...

  12. Electron beam application as pre treatment of sugar cane bagasse to enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    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)

  13. The effect of ethanol-gasoline blends on SI engine energy balance and heat transfer characteristics

    OpenAIRE

    Alrayyes, Taleb

    2011-01-01

    Ethanol is one of a group of hydrocarbon fuels produced from bio-mass which is attracting interest as an alternative fuel for spark ignition engines. Major producers of ethanol include Brazil, from sugar cane, and the USA, from com. Reasons for the growing interest in ethanol include economic development, security of fuel supply and the reduction of net emissions of carbon dioxide relative to levels associated with the use of fossil fuels. Unlike gasoline, which is a mixture of hydrocarbon co...

  14. Microfibrillated cellulose: morphology and accessibility

    Energy Technology Data Exchange (ETDEWEB)

    Herrick, F.W.; Casebier, R.L.; Hamilton, J.K.; Sandberg, K.R.

    1983-01-01

    Microfibrillated cellulose (MFC) is prepared by subjecting dilute slurries of cellulose fibers to repeated high-pressure homogenizing action. A highly microfibrillated product will have a gel-like appearance at 2% concentration in water. Such gels have pseudoplastic viscosity properties and are very fluid when stirred at high shear rate. The relative viscosity of 2% MFC dispersions may be used as a measure of the degree of homogenization or microfibrillation of a given wood cellulose pulp. The water retention value of an MFC product can also be used as an indicator for degree of homogenization. Structurally, MFC appears to be a web of interconnected fibrils and microfibrils, the latter having diameters in the range 10-100 nm as observed in scanning and transmission electron micrographs. Chemical studies have revealed that MFC is only moderately degraded, while being greatly expanded in surface area. The accessibility of cellulose in MFC is only moderately degraded, while being greatly expanded in surface area. The accessibility of cellulose in MFC toward chemical reagents is greatly increased. Higher reactivity was demonstrated in dilute cupriethylenediamine solubility, triphenylmethylation, acetylation, periodate oxidation, and mineral acid and cellulase enzyme hydrolysis rates. 16 references, 8 figures, 7 tables.

  15. Ethanol and oxidative stress.

    Science.gov (United States)

    Sun, A Y; Ingelman-Sundberg, M; Neve, E; Matsumoto, H; Nishitani, Y; Minowa, Y; Fukui, Y; Bailey, S M; Patel, V B; Cunningham, C C; Zima, T; Fialova, L; Mikulikova, L; Popov, P; Malbohan, I; Janebova, M; Nespor, K; Sun, G Y

    2001-05-01

    This article represents the proceedings of a workshop at the 2000 ISBRA Meeting in Yokohama, Japan. The chair was Albert Y. Sun. The presentations were (1) Ethanol-inducible cytochrome P-4502E1 in alcoholic liver disease, by Magnus Ingelman-Sundberg and Etienne Neve; (2) Regulation of NF-kappaB by ethanol, by H. Matsumoto, Y. Nishitani, Y. Minowa, and Y. Fukui; (3) Chronic ethanol consumption increases concentration of oxidized proteins in rat liver, by Shannon M. Bailey, Vinood B. Patel, and Carol C. Cunningham; (4) Antiphospholipids antibodies and oxidized modified low-density lipoprotein in chronic alcoholic patients, by Tomas Zima, Lenka Fialova, Ludmila Mikulikova, Ptr Popov, Ivan Malbohan, Marta Janebova, and Karel Nespor; and (5) Amelioration of ethanol-induced damage by polyphenols, by Albert Y. Sun and Grace Y. Sun. PMID:11391077

  16. The cellulose synthase companion proteins act non-redundantly with CELLULOSE SYNTHASE INTERACTING1/POM2 and CELLULOSE SYNTHASE 6

    OpenAIRE

    Endler, Anne; Schneider, Rene; Kesten, Christopher; Edwin R Lampugnani; Persson, Staffan

    2016-01-01

    ABSTRACT 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 ...

  17. Hydrothermal treatment and ethanol pulping of sunflower stalks.

    Science.gov (United States)

    Caparrós, S; Ariza, J; López, F; Nacimiento, J A; Garrote, G; Jiménez, L

    2008-03-01

    The influence of temperature in the hydrothermal treatment of sunflower stalks on the composition of the liquid fraction obtained was examined. The remaining solid fraction was subjected to ethanol pulping in order to obtain pulp that was used to produce paper sheets. The pulp was characterized in terms of yield, kappa index, viscosity, and cellulose, hemicellulose and lignin contents; and the paper sheets in terms of breaking length, stretch, burst index and tear index. Hydrothermal treatment of the raw material at 190 degrees C provided a liquid phase with maximal hemicellulose-derived oligomers and monosaccharide (glucose, xylose and arabinose) contents (26.9 and 4.2 g/L, respectively). Pulping the solid fraction obtained by hydrothermal treatment at 180 degrees C, with 70% ethanol at a liquid/solid ratio of 8:1 at 170 degrees C for 120 min provided pulp with properties on a par with those of soda pulp from the sunflower stalks, namely: 36.3% yield, 69.1% cellulose, 12.6% hemicellulose, 18.2% lignin and 551 ml/g viscosity. Also, paper sheets obtained from the ethanol pulp were similar in breaking length (3.8 km), stretch (1.23%), burst index (1.15 kN/g) and tear index (2.04 m Nm(2)/g) to those provided by soda pulp. PMID:17369038

  18. Ethanol production from lignocellulose

    Science.gov (United States)

    Ingram, Lonnie O.; Wood, Brent E.

    2001-01-01

    This invention presents a method of improving enzymatic degradation of lignocellulose, as in the production of ethanol from lignocellulosic material, through the use of ultrasonic treatment. The invention shows that ultrasonic treatment reduces cellulase requirements by 1/3 to 1/2. With the cost of enzymes being a major problem in the cost-effective production of ethanol from lignocellulosic material, this invention presents a significant improvement over presently available methods.

  19. 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.

  20. Forage quality and composition measurements as predictors of ethanol yield from maize (Zea mays L. stover

    Directory of Open Access Journals (Sweden)

    de Leon Natalia

    2009-03-01

    Full Text Available Abstract Background 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 used to estimate ethanol yield of maize stover as measured by a simplified pretreatment and simultaneous saccharification and fermentation assay. Twelve maize varieties selected to be diverse for stover digestibility and composition were evaluated. Results Variation in ethanol yield was driven by glucan convertibility rather than by glucan content. Convertibility was highly correlated with ruminal digestibility and lignin content. There was no relationship between structural carbohydrate content (glucan and neutral detergent fiber and ethanol yield. However, when these variables were included in multiple regression equations including convertibility or neutral detergent fiber digestibility, their partial regression coefficients were significant and positive. A regression model including both neutral detergent fiber and its ruminal digestibility explained 95% of the variation in ethanol yield. Conclusion Forage quality and composition measurements may be used to predict cellulosic ethanol yield to guide biofeedstock improvement through agronomic research and plant breeding.

  1. Clostridium thermocellum ATCC27405 transcriptomic, metabolomic and proteomic profiles after ethanol stress

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shihui [ORNL; Giannone, Richard J [ORNL; Dice, Lezlee T [ORNL; Yang, Zamin Koo [ORNL; Engle, Nancy L [ORNL; Tschaplinski, Timothy J [ORNL; Hettich, Robert {Bob} L [ORNL; Brown, Steven D [ORNL

    2012-01-01

    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. 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. 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.

  2. Set-asides can be better climate investment than corn ethanol.

    Science.gov (United States)

    Piñeiro, Gervasio; Jobbágy, Esteban G; Baker, Justin; Murray, Brian C; Jackson, Robert B

    2009-03-01

    Although various studies have shown that corn ethanol reduces greenhouse gas (GHG) emissions by displacing fossil fuel use, many of these studies fail to include how land-use history affects the net carbon balance through changes in soil carbon content. We evaluated the effectiveness and economic value of corn and cellulosic ethanol production for reducing net GHG emissions when produced on lands with different land-use histories, comparing these strategies with reductions achieved by set-aside programs such as the Conservation Reserve Program (CRP). Depending on prior land use, our analysis shows that C releases from the soil after planting corn for ethanol may in some cases completely offset C gains attributed to biofuel generation for at least 50 years. More surprisingly, based on our comprehensive analysis of 142 soil studies, soil C sequestered by setting aside former agricultural land was greater than the C credits generated by planting corn for ethanol on the same land for 40 years and had equal or greater economic net present value. Once commercially available, cellulosic ethanol produced in set-aside grasslands should provide the most efficient tool for GHG reduction of any scenario we examined. Our results suggest that conversion of CRP lands or other set-aside programs to corn ethanol production should not be encouraged through greenhouse gas policies. PMID:19323189

  3. Transcriptomic analysis of Clostridium thermocellum ATCC 27405 cellulose fermentation

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, Catherine K [ORNL; Brown, Steven D [ORNL

    2011-01-01

    The ability of Clostridium thermocellum ATCC 27405 wild-type strain to hydrolyze cellulose and ferment the degradation products directly to ethanol and other metabolic byproducts makes it an attractive candidate for consolidated bioprocessing of cellulosic biomass to biofuels. In this study, whole-genome microarrays were used to investigate the expression of C. thermocellum mRNA during growth on crystalline cellulose in controlled replicate batch fermentations. A time-series analysis of gene expression revealed changes in transcript levels of {approx}40% of genes ({approx}1300 out of 3198 ORFs encoded in the genome) during transition from early-exponential to late-stationary phase. K-means clustering of genes with statistically significant changes in transcript levels identified six distinct clusters of temporal expression. Broadly, genes involved in energy production, translation, glycolysis and amino acid, nucleotide and coenzyme metabolism displayed a decreasing trend in gene expression as cells entered stationary phase. In comparison, genes involved in cell structure and motility, chemotaxis, signal transduction and transcription showed an increasing trend in gene expression. Hierarchical clustering of cellulosome-related genes highlighted temporal changes in composition of this multi-enzyme complex during batch growth on crystalline cellulose, with increased expression of several genes encoding hydrolytic enzymes involved in degradation of non-cellulosic substrates in stationary phase. Overall, the results suggest that under low substrate availability, growth slows due to decreased metabolic potential and C. thermocellum alters its gene expression to (i) modulate the composition of cellulosomes that are released into the environment with an increased proportion of enzymes than can efficiently degrade plant polysaccharides other than cellulose, (ii) enhance signal transduction and chemotaxis mechanisms perhaps to sense the oligosaccharide hydrolysis products

  4. Environmental benefits of ethanol

    International Nuclear Information System (INIS)

    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

  5. Microbial Cellulose Assembly in Microgravity

    Science.gov (United States)

    Brown, R. Malcolm, Jr.

    1998-01-01

    Based on evidence indicating a possible correlation between hypo-gravity conditions and alteration of cellulose production by the gram negative bacterium, Acetobacter xylinum, a ground-based study for a possible long term Space Shuttle flight has been conducted. The proposed experiment for A. xylinum aboard the Shuttle is the BRIC (Biological Research in a Canister), a metal container containing spaces for nine Petri plates. Using a common experimental design, the cellulose production capability as well as the survivability of the A. xylinum strains NQ5 and AY201 have been described. It should now be possible to use the BRIC for the first long term microgravity experiments involving the biosynthesis of cellulose.

  6. 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.

  7. 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

  8. A Global Model for Agriculture and Bioenergy: Application to Biofuel and Food Security in Peru and Tanzania

    OpenAIRE

    Elbehri, Aziz; McDougall, Robert; Horridge, Mark

    2009-01-01

    This paper describes a global model for agriculture and bioenergy (GLOMAB) that incorporates biomass, biofuels and bioelectricity sectors into the GTAP-Energy model by expanding the global GTAP database, production and consumption structures. Biofuels are separated between first- generation (sugar ethanol, starch ethanol) and second- generation (cellulosic ethanol) biofuels and associated biomass feedstocks (maize, sugar cane, crop residues, woody biomass). Beside biofuels, the model also inc...

  9. 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

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

    International Nuclear Information System (INIS)

    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 CO2 is needed to affect competitiveness. (author)

  11. Chemical modification of cellulose for electrospinning applications

    OpenAIRE

    Martín Ferrer, Elena

    2013-01-01

    The aim of the thesis is to develop technology for producing cellulose fatty acid esters that later will be used to produce fibrous materials by means of electrospinning. Main material of the study is cellulose-stearate which is a polymer synthesised by reaction between stearoyl chloride and cellulose. The experimental part consists of synthesis of it by chemical modification of cellulose using ionic liquid as a reaction media. In addition, ionic liquid is also synthesised from the beginning....

  12. Filtration properties of bacterial cellulose membranes

    OpenAIRE

    Lehtonen, Janika

    2015-01-01

    Bacterial cellulose has the same molecular formula as cellulose from plant origin, but it is characterized by several unique properties including high purity, crystallinity and mechanical strength. These properties are dependent on parameters such as the bacterial strain used, the cultivation conditions and post-growth processing. The possibility to achieve bacterial cellulose membranes with different properties by varying these parameters could make bacterial cellulose an interesting materi...

  13. Biocompatibility of Bacterial Cellulose Based Biomaterials

    OpenAIRE

    Omar P. Troncoso; Solene Commeaux; Torres, Fernando G.

    2012-01-01

    Some bacteria can synthesize cellulose when they are cultivated under adequate conditions. These bacteria produce a mat of cellulose on the top of the culture medium, which is formed by a three-dimensional coherent network of pure cellulose nanofibers. Bacterial cellulose (BC) has been widely used in different fields, such as the paper industry, electronics and tissue engineering due to its remarkable mechanical properties, conformability and porosity. Nanocomposites based on BC have received...

  14. A Molecular Description of Cellulose Biosynthesis

    OpenAIRE

    McNamara, Joshua T.; Morgan, Jacob L.W.; Zimmer, Jochen

    2015-01-01

    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 ...

  15. Ethanol from lignocellulosic crops

    Science.gov (United States)

    Wood, grasses, and most of the plant litter represent the major part of the biomass in nature and are collectively called lignocellulose. Regardless of the source, lignocellulosic materials are mainly composed of cellulose, hemicellulose, and lignin. Over 150 billion tonne of organic substances are ...

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

    International Nuclear Information System (INIS)

    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 US$1=R$2.15 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 CO2 is needed to affect competitiveness. - Research highlights: →The relative cost of ethanol produced in the US and imported from Brazil is shown to depend on currency exchange rate, feedstock costs, and co-product credits. →In 2006-2008, the cost of corn ethanol is estimated to be 15% lower than the cost of imported sugarcane ethanol at US ports. →A carbon pricing policy could affect relative costs in favor of sugarcane ethanol, but only at a high carbon price.

  17. The trafficking and behavior of cellulose synthase and a glimpse of potential cellulose synthesis regulators

    Institute of Scientific and Technical Information of China (English)

    Logan BASHLINE; Juan DU; Ying GU

    2011-01-01

    Cellulose biosynthesis is a topic of intensive research not only due to the significance of cellulose in the integrity of plant cell walls,but also due to the potential of using cellulose,a natural carbon source,in the production ot biofuels.Characterization of the composition,regulation,and trafficking of cellulose synthase complexes (CSCs) is critical to an understanding of cellulose biosynthesis as well as the characterization of additional proteins that contribute to the production of cellulose either through direct interactions with CSCs or through indirect mechanisms.In this review,a highlight of a few proteins that appear to affect cellulose biosynthesis,which includes:KORRIGAN (KOR),Cellulose Synthase-Interactive Protein 1 (CSI1),and the poplar microtubule-associated protein,PttMAP20,will accompany a description of cellulose synthase (CESA) behavior and a discussion of CESA trafficking compartments that might act in the regulation of cellulose biosynthesis.

  18. Adsorption and desorption of cellulose derivatives.

    NARCIS (Netherlands)

    Hoogendam, C.W.

    1998-01-01

    Cellulose derivatives, in particular carboxymethyl cellulose (CMC) are used in many (industrial) applications. The aim of this work is to obtain insight into the adsorption mechanism of cellulose derivatives on solid-liquid interfaces.In chapter 1 of this thesis we discuss some appl

  19. Iodine catalyzed acetylation of starch and cellulose

    Science.gov (United States)

    Starch and cellulose, earth's most abundant biopolymers, are of tremendous economic importance. Over 90% of cotton and 50% of wood are made of cellulose. Wood and cotton are the major resources for all cellulose products such as paper, textiles, construction materials, cardboard, as well as such c...

  20. 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

  1. 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.

  2. Impact of Biofield Treatment on Chemical and Thermal Properties of Cellulose and Cellulose Acetate

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    Cellulose being an excellent biopolymer has cemented its place firmly in many industries as a coating material, textile, composites, and biomaterial applications. In the present study, we have investigated the effect of biofield treatment on physicochemical properties of cellulose and cellulose acetate. The cellulose and cellulose acetate were exposed to biofield and further the chemical and thermal properties were investigated. X-ray diffraction study asserted that the biofield treatment did...

  3. 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.

  4. Combined Application of Microbial Cellulose and Papaver macrostomum Extract on Bedsore Microorganisms

    Directory of Open Access Journals (Sweden)

    Anita Khanafari,

    2013-05-01

    Full Text Available Background: Bedsore is one of the major problems in all the societies as patients are confined to bed. Due to antibiotic resistant strains being a significant obstacle for cure, many plants and herbs are being used by researchers as medicinal compounds..Objectives: The investigation of synergistic effect of cellulose biopolymer and Papaver macrostomum extract on bedsores bacterial community..Materials and Methods: Acetobacter xylinum PTTC 1734 was cultured in Schramm-Hestrin (SH medium and incubated at 30°C for 24-48 hours. NaOH treatment and absolute ethanol were used to extract cellulose biopolymer and plant antimicrobial substance, respectively. The Biopolymer structure was scanned by a Scanning electron microscope (SEM. Antimicrobial activities, minimum inhibitory concentration (MIC, and minimum bactericidal concentration (MBC of these extracts were all determined separately. The effective concentration of each extract's alone, combined, and synergistic effects were evaluated. Biopolymer absorption efficiency was assayed as the absorbent bed..Results: Pesudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus were the dominate bacteria isolated from bedsore samples. Antimicrobial effects of cellulose, P. macrostomum extract, and the combination of both were determined on the isolated bacteria as 1, 10, and 15 mm respectively. 100-1000μl/mL of flower ethanol extract concentrations of P. macrostomum indicated the maximum effect on mixed bedsore's bacteria rather than leaf and mixed extraction. Concentrations 500-1000μl/mL decreased the bacterial bedsore's growth and completely inhibited it. 3.5g/L of cellulose biopolymer was obtained from A. xylinum broth culture medium. Scanning electron microscopy analysis confirmed the branched structure of this polymer. Cellulose absorption efficiency was evaluated to be 14.5ml/g in this investigation. Because of high-absorbance of bio-cellulose, combined plant extraction with this biopolymer

  5. High performance cellulose nanocomposites: comparing the reinforcing ability of bacterial cellulose and nanofibrillated cellulose

    OpenAIRE

    Lee, K. Y.; Tammelin, T.; Schulfter, K.; Kiiskinen, H.; Samela, J.; Bismarck, A.

    2012-01-01

    This work investigates the surface and bulk properties of nanofibrillated cellulose (NFC) and bacterial cellulose (BC), as well as their reinforcing ability in polymer nanocomposites. BC possesses higher critical surface tension of 57 mN m(-1) compared to NFC (41 mN m(-1)). The thermal degradation temperature in both nitrogen and air atmosphere of BC was also found to be higher than that of NFC. These results are in good agreement with the higher crystallinity of BC as determined by XRD, meas...

  6. 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.; Ahring, Birgitte Kiær; Thomsen, Anne Belinda

    2004-01-01

    -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...... conversion efficiency during SSF was 50, 62 65 and 70% for a total enzyme loading of 5, 10, 15 and 25 FPU g(-1) DS, respectively. Hence, this study shows that wet oxidation is a suitable pre-treatment for the conversion of organic waste carbohydrates into ethanol and that compatible conversion yields (60...

  7. Ethanol fuels in Brazil

    International Nuclear Information System (INIS)

    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

  8. Ethanol production with simultaneous utilization of raw materials containing starch and lignocellulose-containing; Ethanolproduktion mit simultanem Einsatz von staerke- und lignocellulosehaltigen Rohstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Fleischer, Sven; Buck, Michael; Senn, Thomas [Hohenheim Univ., Stuttgart (Germany). Fachgebiet Gaerungstechnologie

    2010-07-01

    Ethanol production from cellulose-rich raw materials has again been the subject of much discussion during the past few years. Some new processes were developed during that time, all of which are more or less based on the acid hydrolysis process developed in the thirties of the past century. This technology is not suited for biogas plants because of the sulphuric acid involved. However, ethanol production combined with biogas production offers a chance in principle to make use of the cellulose and hemicellulose that are not converted in the ethanol process; these could be converted into biogas in the biogas plant. This would also ensure energetic utilization of pentoses from lignocellulose. The authors describe a process for utilization of cellulose-rich material which works without acid and requires very moderate hydrothermal process conditions (70 minutes at 150 degC). With straw, efficiencies up to 15 percent were achieved; with maize, efficiencies were up to 21.5 percent.

  9. Biotechnological processes for conversion of corn into ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Bothast, R.J.; Schlicher, M.A. [National Corn-To-Ethanol Research Center, Southern Illinois Univ. Edwardsville, Edwardsville, IL (United States)

    2005-04-01

    Ethanol has been utilized as a fuel source in the United States since the turn of the century. However, it has repeatedly faced significant commercial viability obstacles relative to petroleum. Renewed interest exists in ethanol as a fuel source today owing to its positive impact on rural America, the environment and United States energy security. Today, most fuel ethanol is produced by either the dry grind or the wet mill process. Current technologies allow for 2.5 gallons (wet mill process) to 2.8 gallons (dry grind process) of ethanol (1 gallon = 3.7851) per bushel of corn. Valuable co-products, distillers dried grains with solubles (dry grind) and corn gluten meal and feed (wet mill), are also generated in the production of ethanol. While current supplies are generated from both processes, the majority of the growth in the industry is from dry grind plant construction in rural communities across the corn belt. While fuel ethanol production is an energy-efficient process today, additional research is occurring to improve its long-term economic viability. Three of the most significant areas of research are in the production of hybrids with a higher starch content or a higher extractable starch content, in the conversion of the corn kernel fiber fraction to ethanol, and in the identification and development of new and higher-value co-products. (orig.)

  10. Plasma-Assisted Pretreatment of Wheat Straw for Ethanol Production

    DEFF Research Database (Denmark)

    Schultz-Jensen, Nadja; Kádár, Zsófia; Thomsen, Anne Belinda;

    2011-01-01

    The potential of wheat straw for ethanol production after pretreatment with O3 generated in a plasma at atmospheric pressure and room temperature followed by fermentation was investigated. We found that cellulose and hemicellulose remained unaltered after ozonisation and a subsequent washing step...... carboxylic acids and phenolic compounds were found, e.g., vanillic acid, acetic acid, and formic acid. Some components had the highest concentration at the beginning of the ozonisation process (0.5, 1 h), e.g., 4-hydroxybenzladehyde, while the concentration of others increased during the entire pretreatment...

  11. Production of bacterial cellulose from alternate feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    D. N. Thompson; M. A. Hamilton

    2000-05-07

    Production of bacterial cellulose by Acetobacter xylinum ATCC 10821 and 23770 in static cultures was tested from unamended food process effluents. Effluents included low- and high-solids potato effluents (LS and HS), cheese whey permeate (CW), and sugar beet raffinate (CSB). Strain 23770 produced 10% less cellulose from glucose than did 10821, and diverted more glucose to gluconate. Unamended HS, CW, and CSB were unsuitable for cellulose production by either strain, while LS was unsuitable for production by 10821. However, 23770 produced 17% more cellulose from LS than from glucose, indicating unamended LS could serve as a feedstock for bacterial cellulose.

  12. Production of Bacterial Cellulose from Alternate Feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, David Neil; Hamilton, Melinda Ann

    2000-05-01

    Production of bacterial cellulose by Acetobacter xylinum ATCC 10821 and 23770 in static cultures was tested from unamended food process effluents. Effluents included low- and high-solids potato effluents (LS & HS), cheese whey permeate (CW), and sugar beet raffinate (CSB). Strain 23770 produced 10% less cellulose from glucose than did 10821, and diverted more glucose to gluconate. Unamended HS, CW, and CSB were unsuitable for cellulose production by either strain, while LS was unsuitable for production by 10821. However, 23770 produced 17% more cellulose from LS than from glucose, indicating unamended LS could serve as a feedstock for bacterial cellulose.

  13. Cost estimate for the production of ethanol from spent sulphite liquors and wood residues

    International Nuclear Information System (INIS)

    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

  14. Microwave-irradiation of lignocellulosic materials, 10: Conversion of microwave-irradiated agricultural wastes into ethanol

    International Nuclear Information System (INIS)

    Agricultural wastes, including rice straw, rice hulls and sugarcane bagasse, pretreated by continuous microwave irradiation, were converted into ethanol. Almost all hemicelluloses were autohydrolysed during the pretreatment at 210-220°C. Addition of acetic acid (0.5% concn) into irradiation medium permitted lowering temp. by 10-30°. Most of the cellulose in pretreated samples of rice straw and bagasse was more effectively digested by cellulases because of the increase in their enzymatic susceptibility. Removal of hemicelluloses had, however, no direct connection with the increase in digestibility. Glucose produced by enzymatic saccharification was completely converted into ethanol. Yields of ethanol produced/kg DW of the pretreated samples of rice straw and bagasse were 378 ml and 285 ml, respectively. Since the severe conditions of pretreatment to increase the enzymatic susceptibility required a considerable amount of electric power, the milder conditions reduced the energy consumption for ethanol production

  15. Cellulose nanomaterials in water treatment technologies.

    Science.gov (United States)

    Carpenter, Alexis Wells; de Lannoy, Charles-François; Wiesner, Mark R

    2015-05-01

    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

  16. Polymorphy in native cellulose: recent developments

    International Nuclear Information System (INIS)

    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 13C-NMR studies. More recently, they have proposed, on the basis of high resolution solid-state 13C-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 13C-NMR investigations

  17. Operant Ethanol Self-Administration in Ethanol Dependent Mice

    OpenAIRE

    Lopez, Marcelo F; Howard C Becker

    2014-01-01

    While rats have been predominantly used to study operant ethanol self-administration behavior in the context of dependence, several studies have employed operant conditioning procedures to examine changes in ethanol self-administration behavior as a function of chronic ethanol exposure and withdrawal experience in mice. This review highlights some of the advantages of using operant conditioning procedures for examining the motivational effects of ethanol in animals with a history of dependenc...

  18. 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.

  19. Allocation of Energy Use in the Biomass-based Fuel Ethanol System and Its Use in Decision Making

    Institute of Scientific and Technical Information of China (English)

    LENG Ru-bo; YU Sui-ran; FANG Fang; DAI Du; WANG Cheng-tao

    2005-01-01

    The Chinese government is developing biomass ethanol as one of its automobile fuels for energy security and environmental improvement reasons. The energy efficiency of the biomass-based fuel ethanol is critical issue. To investigate the energy use in the three biomass-base ethanol fuel systems, energy content approach, Market value approach and Product displacement approach methods were used to allocate the energy use based on life cycle energy assessment. The results shows that the net energy of corn based, wheat based, and cassava-based ethanol fuel are 12543MJ, 10299MJ and 13112MJ when get one ton biomassbased ethanol, respectively, and they do produce positive net energy.

  20. High pressure HC1 conversion of cellulose to glucose

    Energy Technology Data Exchange (ETDEWEB)

    Antonoplis, Robert Alexander; Blanch, Harvey W.; Wilke, Charles R.

    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

  1. Environmental aspects of ethanol-based fuels from Brassica carinata. A case study of second generation ethanol

    International Nuclear Information System (INIS)

    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

  2. Ethanol production via fungal decomposition and fermentation of biomass. Phase II (FY 1981) annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Antonopoulos, A. A.; Wene, E. G.

    1981-10-01

    This program has as its main goal the isolation and development of Fusarium strains that can efficiently and economically decompose plant polysaccharides to pentoses and hexoses and ferment them to ethanol for fuel purposes. During Phase II (FY 1981) of this program, more than 800 new Fusarium isolates were isolated and screened. All showed cellulolytic activity. The Fusarium mutant ANL 3-72181 (derived after uv exposure of ANL 22 isolate) produced 2.45 iu cellulase after 14 days. This cellulase activity was achieved in the presence of 0.7 mg/mL extracellular protein. In separate tests, the use of both proteose peptone and yeast extract with 1% cellulose increased the production of extracellular protein three times over that on cellulose alone. Initial fermentation by Fusarium strains on 1% glucose produced up to 4.2 mg/mL ethanol in 48 hours. All Fusarium isolates and mutants found during this period were screened for xylose fermentation. Ethanol production during early experimentation required from 120 to 144 hours to yield 4.0 to 4.5 mg/mL ethanol from 1% xylose solutions. Through continuous selection of isolates, this time was reduced to 66 hours. By recycling Fusarium cell mass, fermentations of 1% xylose yielded 4.0 to 4.3 mg/mL ethanol in 48 hours. Consecutive fermentations of 2% xylose produced an average of 8.1 mg/mL ethanol in 48 hours. Fermentation of a 4.5% xylose + 2% glucose solution produced 21 mg/mL ethanol and 0.8 mg/mL acetic acid, while fermentation of a 7% xylose + 2% glucose solution yielded 25.5 mg/mL ethanol and 0.85 mg/mL acetic acid; these fermentations were aerated at a rate of 0.03 v/v-min.

  3. 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

  4. Ethanol: economic gain or drain?

    OpenAIRE

    Joshua A. Byrge; Kevin L. Kliesen

    2008-01-01

    Corn-based ethanol can make a dent in demand for oil, but at what price? Food costs go up. Environmental damage worsens. If oil prices fall, ethanol production will probably collapse-as it did 20 years ago.

  5. Compatibility between cellulose and hydrophobic polymer provided by microfibrillated lignocellulose.

    Science.gov (United States)

    Gindl-Altmutter, Wolfgang; Obersriebnig, Michael; Veigel, Stefan; Liebner, Falk

    2015-01-01

    Microfibrillated lignocellulose (MFLC) was produced from wood subjected to partial lignin extraction using an ethanol/water mixture. After homogenization, the average fibril diameter of MFLC was in the same range as conventional microfibrillated cellulose (MFC). Although MFLC exhibited higher wettability with water compared to MFC, AFM adhesion force measurements revealed high variability in surface polarity of MFLC compared to MFC. Specifically, domains of higher polarity than in MFC but also domains of lower polarity than in MFC were observed in MFLC. This tendency towards amphiphilic behavior of MFLC was used to provide enhanced compatibility with polycaprolactone and polystyrene matrices. With both polymers, a significantly more homogeneous distribution of fibrils was achieved using MFLC compared to MFC. In line with better dispersion of the fibrils, significantly more efficient mechanical reinforcement of polymers was obtained using MFLC compared to MFC. PMID:25348210

  6. Ethanol toxicity and oxidative stress

    OpenAIRE

    Bondy, SC

    1992-01-01

    The mechanisms underlying the toxicity of ethanol have been the subject of much study, but are not well understood. Unlike many selective pharmacological agents, ethanol clearly has several major loci of action. One deleterious factor in ethanol metabolism is the potential for generation of excess amounts of free radicals. The extent to which this activity accounts for the overall toxicity of ethanol is unknown. This review outlines the enzymic steps that have the capacity to generate reactiv...

  7. Hepatotoxicity of ethanol in mice.

    OpenAIRE

    Goldin, R D; Wickramasinghe, S. N.

    1987-01-01

    Mice continuously exposed to ethanol vapour (for up to 19 days) developed fatty change in the liver (from 2 days onwards) and lesions resembling those of alcoholic hepatitis in man (from 5 days onwards). They also showed biochemical evidence of liver cell damage. Sera from ethanol-treated animals contained immunoglobulins that bound to the hepatocytes of ethanol-treated but not of control animals suggesting that exposure to ethanol was followed by an immunological response to a hepatocyte neo...

  8. 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.

  9. Reactions of ethanol on Ru

    NARCIS (Netherlands)

    Sturm, J. M.; Lee, C. J.; F. Bijkerk,

    2013-01-01

    The adsorption and reactions of ethanol on Ru(0001) were studied with temperature-programmed desorption (TPD) and reflection-absorption infrared spectroscopy (RAIRS). Ethanol was found to adsorb intact onto Ru(0001) below 100 K. From 175 K to 200 K, ethanol is converted into ethoxy groups, which und

  10. Sorghum to Ethanol Research

    Energy Technology Data Exchange (ETDEWEB)

    Jeff Dahlberg, Ph D; Ed Wolfrum, Ph D

    2010-06-30

    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

  11. Sorghum to Ethanol Research

    Energy Technology Data Exchange (ETDEWEB)

    Dahlberg, Jeff; Wolfrum, Ed

    2010-06-30

    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

  12. Sorghum to Ethanol Research

    Energy Technology Data Exchange (ETDEWEB)

    Dahlberg, Jeff; Wolfrum, Ed

    2010-06-30

    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

  13. 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.

  14. Surface modification of cellulose fibres

    Directory of Open Access Journals (Sweden)

    Mohamed Naceur Belgacem

    2005-06-01

    Full Text Available Several approaches to the modification of cellulose fibres are described, namely: (i physical treatments such as corona or plasma treatments under different atmospheres; (ii grafting with hydrophobic molecules using well-known sizing compounds; (iii grafting with bi-functional molecules, leaving one of the functions available for further exploitation; and (iv grafting with organometallic compounds. The modified surfaces were characterized by elemental analysis, contact angle measurements, inverse gas chromatography, X-ray photoelectron and infrared spectroscopy, wettability, etc. These different tools provided clear-cut evidence of the occurrence of chemical reactions between the grafting agent used and the hydroxy functions of the cellulose surface, as well as of the existence of covalent bonding in the ensuing composite materials between the matrix and the fibres through the use of doubly reactive coupling agents.

  15. 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.

  16. Cell adhesion on cellulose nanofibrils

    OpenAIRE

    Liljeström, Anna

    2016-01-01

    Cellulose nanofibrils (CNF) is an emerging biomaterial suitable for medical research. CNF hydrogel has been used as a three dimensional platforms for cell culture. This thesis aims to understand how human liver carcinoma (HepG2) cells interact with CNF. Measurements were performed with Quartz crystal microbalance with dissipation in order to quantify cell adsorption on CNF. Furthermore, the effect of the cell medium on the viscoelastic properties of CNF and on cell-CNF interactions were ...

  17. Lowering costs of microbial cellulose

    OpenAIRE

    Pajuelo, María González; Bungay, Henry; Hogg, Tim; Vasconcelos, Isabel

    1997-01-01

    We have been conducting research with Acetobacter xylinium for microbial conversion of sugars to cellulose. A rotating disk biological contactor should lower costs considerably because its production rates are greater than for the usual method of surface culture. Another major cost saving comes from replacing expensive sugars in the medium with sugars derived from wastes. Extracts of spent grapes from wastes of Portuguese wine factories supply suitable sugars for good production of micr...

  18. The Cellulase KORRIGAN Is Part of the Cellulose Synthase Complex

    NARCIS (Netherlands)

    Vain, T.; Crowell, E.F.; Timpano, H.; Biot, E.; Desprez, T.; Mansoori Zangir, N.; Trindade, L.M.; Pagant, S.; Robert, S.; Hofte, H.; Gonneau, M.; Vernhettes, S.

    2014-01-01

    Plant growth and organ formation depend on the oriented deposition of load-bearing cellulose microfibrils in the cell wall. Cellulose is synthesized by a large relative molecular weight cellulose synthase complex (CSC), which comprises at least three distinct cellulose synthases. Cellulose synthesis

  19. Bioconversion of plant biomass to ethanol. Third quarterly and bimonthly report, July 1--September 30, 1977

    Energy Technology Data Exchange (ETDEWEB)

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

    1977-10-01

    The studies of biological delignification have focused on the adaptation of the lignocellulosic thermophilic mold Chrysosporium pruinosum to growth on maple wood fibers. The addition of trace elements and thiamine hydrochloride to the C. pruinosum growth medium has been found to stimulate culture growth by a factor of about two. The nutritional salt tolerances of C. pruinosum have been determined. Nutrient concentrations below of about 2.5 times that required to support C. pruinosum growth have no significant deleterious inhibitory effects. Work on the design and construction of a bench-top high solids biological delignification bioreactor has been initiated. The mixed culture microbiological studies have focused mainly on nutritional growth requirements and rates of cellulose digestion and ethanol production. In small test tube mixed culture (sporocytophaga (US) + thermophilic bacillus (NW)) fermentations, the rate of cellulose degradation was found to proceed at a very high volumetric efficiency, 2.4 g/l-hr. The yield of ethanol from the mixed culture fermentation of cellulose varied between 24 and 50% of theoretical. The higher yields were obtained in the presence of insoluble calcium carbonate added to retard the rate of pH decline and to increase the CO/sub 2/ tension. Bench-top fermentations at the 1 liter scale have been performed to verify, under controlled pH, agitation, and dissolved oxygen conditions, the results achieved in small scale test tube experiments. The specific growth rate of thermophilic bacillus NW on glucose was calculated to be 0.59 hr/sup -1/. In mixed culture fermentations 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. Ethanol production in these fermentor runs was slower than the rates of acetic acid production. In the fermentation of microcrystalline cellulose, 2,3 butanediol was also produced.

  20. Nanocrystalline cellulose for covert optical encryption

    Science.gov (United States)

    Zhang, Yu Ping; Chodavarapu, Vamsy P.; Kirk, Andrew G.; Andrews, Mark P.

    2012-02-01

    Nanocrystalline cellulose solid films derived from spruce pulp exhibit iridescence when cast from chiral nematic aqueous phase suspensions of the nanocrystals. Iridescence is a color travel phenomenon that might have potential for overt encryption as an anti-counterfeiting measure. The iridescent phase also offers an intrinsic level of covert encryption by virtue of the fact that films of NCC reflect left-circularly polarized light. Addition of TINOPAL, an optical brightening agent (OBA), adds a third level of (covert) encryption potential since the chromophore exhibits strong fluorescence when excited at ultra-violet wavelengths. The overall result is a selectively polarizing fluorescent iridescent film. We study the impact of additions of OBA on NCC iridescence, optical activity, and physical structure variation with polarized optical microscopy, circular dichroism spectropolarimetry and zeta potential analysis. Increasing OBA additions increase the chiral nematic pitch of NCC films, and this in turn alters chiral nematic domain structure in the solid film. Under low concentration conditions defined by our experiments, OBA yields intense UV fluorescence, without compromising the visible light iridescent properties of the film. The potential security offered by NCC and its optical responses can be authenticated using a UV light source such as is commonly used for banknote verification, a circular polarizer in conjunction with an iridescent feature which can be verified by the eye or by chiral spectrometry.

  1. Monetary value of the environmental and health externalities associated with production of ethanol from biomass feedstocks

    International Nuclear Information System (INIS)

    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 PM10, NOX, and PM2.5 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.

  2. Production of Ethanol from Water Hyacinth (Eichhornia crassipes) by Zymomonas mobilis CP4: Optimization Studies

    OpenAIRE

    V. Ponnusami; D. Gowdhaman; T. Kasthuri

    2012-01-01

    Ethanol is produced from water hyacinth, an aquatic weed plant, comprising of cellulose, hemicelluloses and lignin by a two-step method. Water hyacinth was pretreated with different concentration of sulfuric acid, detoxified with CaOH and NaOH and then fermented using Zymomonas mobilis CP4 (a recombinant strain). Batch fermentation and Simultaneous Saccharification and Fermentation (SSF) were performed and the ethanol yields were compared. Central Composite Design (CCD) is conducted to optimi...

  3. Enzymatic digestibility and ethanol fermentability of AFEX-treated starch-rich lignocellulosics such as corn silage and whole corn plant

    OpenAIRE

    Thelen Kurt D; Sousa Leonardo; Bals Bryan; Krishnan Chandraraj; Chundawat Shishir PS; Shao Qianjun; Dale Bruce E; Balan Venkatesh

    2010-01-01

    Abstract Background Corn grain is an important renewable source for bioethanol production in the USA. Corn ethanol is currently produced by steam liquefaction of starch-rich grains followed by enzymatic saccharification and fermentation. Corn stover (the non-grain parts of the plant) is a potential feedstock to produce cellulosic ethanol in second-generation biorefineries. At present, corn grain is harvested by removing the grain from the living plant while leaving the stover behind on the fi...

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

    OpenAIRE

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

    2016-01-01

    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 simpl...

  5. Exergy and CO2 Analyses as Key Tools for the Evaluation of Bio-Ethanol Production

    OpenAIRE

    Qian Kang; Tianwei Tan

    2016-01-01

    The background of bioethanol as an alternative to conventional fuels is analyzed with the aim of examining the efficiency of bioethanol production by first (sugar-based) and second (cellulose-based) generation processes. Energy integration is of paramount importance for a complete recovery of the processes’ exergy potential. Based upon literature data and our own findings, exergy analysis is shown to be an important tool in analyzing integrated ethanol production from an efficiency and cost p...

  6. Production of ethanol from cellobiose using immobilized beta-glucosidase coentrapped with yeast in alginate gels

    Energy Technology Data Exchange (ETDEWEB)

    Kierstan, M.; McHale, A.; Coughlan, M.P.

    1982-06-01

    Enzymatic hydrolysis of cellulose by Talaromyces emersonii is slowed markedly by the accumulation of considerable quantities of cellobiose. This article outlines a novel method for overcoming this problem whereby a culture filtrate containing a complete cellulase system be used in combination with calcium alginate gels containing both yeast and immobilized beta-glucosidase. As a preliminary to a full study, the experimental results of cellobiose conversion to ethanol are reported. (Refs. 13).

  7. A lignocellulosic ethanol strategy via nonenzymatic sugar production: Process synthesis and analysis

    OpenAIRE

    Han, Jeehoon; Luterbacher, Jeremy S.; Alonso, David Martin; Dumesic, James A.; Maravelias, Christos T.

    2015-01-01

    The work develops a strategy for the production of ethanol from lignocellulosic biomass. In this strategy, the cellulose and hemicellulose fractions are simultaneously converted to sugars using a γ-valerolactone (GVL) solvent containing a dilute acid catalyst. To effectively recover GVL for reuse as solvent and biomass-derived lignin for heat and power generation, separation subsystems, including a novel CO2-based extraction for the separation of sugars from GVL, lignin and humins have been d...

  8. 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),

  9. Effects of reaction conditions on cellulose structures synthesized in vitro by bacterial cellulose synthases.

    Science.gov (United States)

    Penttilä, Paavo A; Sugiyama, Junji; Imai, Tomoya

    2016-01-20

    Cellulose was synthesized by cellulose synthases extracted from the Komagataeibacter xylinus (formerly known as Gluconacetobacter xylinus). The effects of temperature and centrifugation of the reaction solution on the synthesis products were investigated. Cellulose with number-average degree of polymerization (DPn) roughly in the range 60-80 and cellulose II crystal structure was produced under all conditions. The amount of cellulose varied with temperature and centrifugation, and the centrifugation at 2000 × g also slightly reduced the DPn. Cellulose production was maximal around the temperature 35 °C and without centrifugation. At higher temperatures and during centrifugation at 2000 × g the proteins started to denature, causing differences also in the morphology of the cellulosic aggregates, as seen with electron microscopy. These observations serve as a basis for discussions about the factors affecting the structure formation and chain length of in vitro synthesized cellulose. PMID:26572398

  10. Micromechanics and poroelasticity of hydrated cellulose networks.

    Science.gov (United States)

    Lopez-Sanchez, P; Rincon, Mauricio; Wang, D; Brulhart, S; Stokes, J R; Gidley, M J

    2014-06-01

    The micromechanics of cellulose hydrogels have been investigated using a new rheological experimental approach, combined with simulation using a poroelastic constitutive model. A series of mechanical compression steps at different strain rates were performed as a function of cellulose hydrogel thickness, combined with small amplitude oscillatory shear after each step to monitor the viscoelasticity of the sample. During compression, bacterial cellulose hydrogels behaved as anisotropic materials with near zero Poisson's ratio. The micromechanics of the hydrogels altered with each compression as water was squeezed out of the structure, and microstructural changes were strain rate-dependent, with increased densification of the cellulose network and increased cellulose fiber aggregation observed for slower compressive strain rates. A transversely isotropic poroelastic model was used to explain the observed micromechanical behavior, showing that the mechanical properties of cellulose networks in aqueous environments are mainly controlled by the rate of water movement within the structure. PMID:24784575

  11. Cellulose Synthases and Synthesis in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Anne Endler; Staffan Persson

    2011-01-01

    Plant cell walls are complex structures composed of high-molecular-weight polysaccharides,proteins,and lignins. Among the wall polysaccharides,cellulose,a hydrogen-bonded β-1,4-linked glucan microfibril,is the main load-bearing wall component and a key precursor for industrial applications. Cellulose is synthesized by large multi-meric cellulose synthase (CesA) complexes,tracking along cortical microtubules at the plasma membrane. The only known components of these complexes are the cellulose synthase proteins. Recent studies have identified tentative interaction partners for the CesAs and shown that the migratory patterns of the CesA complexes depend on phosphorylation status. These advances may become good platforms for expanding our knowledge about cellulose synthesis in the near future. In addition,our current understanding of cellulose chain polymerization in the context of the CesA complex is discussed.

  12. CELLULOSE POWDER FROM OLIVE INDUSTRY SOLID WASTE

    Directory of Open Access Journals (Sweden)

    Othman A. Hamed,

    2012-07-01

    Full Text Available In the present work, a method for extracting cellulose from olive industry solid waste has been developed. The method involves subjecting solid olive waste to kraft pulping, followed by multistep bleaching processes. The totally free chlorine chemical bleaching sequence APEP was the most effective and gave an average cellulose yield of about 35%. The extracted cellulose was extensively characterized using FTIR, EMS, HPLC, and viscometry. Our key finding in this study is that the extracted cellulose was found to have physio-chemical properties that are similar to those of conventional microcrystalline cellulose (MCC. This is important, as our results show how lignocellulosic agricultural wastes can be utilized to produce high value cellulose powder.

  13. 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.

  14. 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)

  15. Transportation impacts of increased ethanol production: A kansas case study

    OpenAIRE

    Babcock, Michael S.

    2010-01-01

    The rapid expansion of the U.S. biofuel industry has driven the Kansas agricultural transportation market into a new era. Nationally, fuel alcohol production rose from 1,630 million gallons in 2000 to 9,239 million in 2008, a 467% increase. The number of ethanol production plants increased from 54 in January 2000 to 170 in January 2009, a 215% increase. Many factors have contributed to the growth of the U.S. ethanol industry. Energy security and energy independence from unstable foreign count...

  16. Size Effects of Nano-crystalline Cellulose

    Institute of Scientific and Technical Information of China (English)

    Guo Kang LI; Xiao Fang LI; Yong JIANG; Mei Zhen ZENG; En Yong DING

    2003-01-01

    Natural cellulose with the crystal form of cellulose Ⅰ, when treated with condensed lye(e.g. 18%NaOH), can change into new crystal form of cellulose Ⅱ. But the nano-crystallinecellulose(NCC) can do it when only treated with dilute lye (e.g. 1%NaOH) at room temperatureand even can dissolve into slightly concentrated lye (e.g. 4%NaOH).

  17. Bulk and interfacial properties of cellulose ethers

    OpenAIRE

    Bodvik, Rasmus

    2012-01-01

    This work summarizes several studies that all concern cellulose ethers of the types methylcellulose (MC) hydroxypropylmethylcellulose (HPMC) and ethyl(hydroxyethyl)cellulose (EHEC). They share the feature of negative temperature response, as they are soluble in water at room temperature but phase separate and sometimes form gels at high temperatures. The different types of viscosity transitions occurring in these three cellulose ethers are well-known. However, earlier studies have not solved ...

  18. Drag Reduction of Bacterial Cellulose Suspensions

    OpenAIRE

    Ogata, Satoshi; Numakawa, Tetsuya; Kubo, Takuya

    2010-01-01

    Drag reduction due to bacterial cellulose suspensions with small environmental loading was investigated. Experiments were carried out by measuring the pressure drop in pipe flow. It was found that bacterial cellulose suspensions give rise to drag reduction in the turbulent flow range. We observed a maximum drag reduction ratio of 11% and found that it increased with the concentration of the bacterial cellulose suspension. However, the drag reduction effect decreased in the presence of mechani...

  19. Drag Reduction of Bacterial Cellulose Suspensions

    OpenAIRE

    Satoshi Ogata; Tetsuya Numakawa; Takuya Kubo

    2011-01-01

    Drag reduction due to bacterial cellulose suspensions with small environmental loading was investigated. Experiments were carried out by measuring the pressure drop in pipe flow. It was found that bacterial cellulose suspensions give rise to drag reduction in the turbulent flow range. We observed a maximum drag reduction ratio of 11% and found that it increased with the concentration of the bacterial cellulose suspension. However, the drag reduction effect decreased in the presence of mechani...

  20. Cellulose biosynthesis and function in bacteria.

    OpenAIRE

    Ross, P; Mayer, R; Benziman, M

    1991-01-01

    The current model of cellulose biogenesis in plants, as well as bacteria, holds that the membranous cellulose synthase complex polymerizes glucose moieties from UDP-Glc into beta-1,4-glucan chains which give rise to rigid crystalline fibrils upon extrusion at the outer surface of the cell. The distinct arrangement and degree of association of the polymerizing enzyme units presumably govern extracellular chain assembly in addition to the pattern and width of cellulose fibril deposition. Most e...

  1. Liquid crystalline cellulose derivatives for mirrorless lasing

    OpenAIRE

    Wenzlik, Daniel

    2013-01-01

    In this thesis cholesteric films made of liquid crystalline cellulose derivatives with improved optical properties were prepared. The choice of the solvent, hydrogen bond influencing additives, the synthetic realization of a very high degree of substitution on the cellulosic polymer and the use of mechanical stirring at the upper concentration limit of the liquid crystalline range were the basis for an improved alignment of the applied cellulose tricarbamates. In combination with a tuned subs...

  2. Lyocell, The New Generation of Regenerated Cellulose

    OpenAIRE

    Éva Borbély

    2008-01-01

    For the majority of the last century, commercial routes to regenerated cellulosefibres have coped with the difficulties of making a good cellulose solution by using an easyto dissolve derivative (e.g. xanthane in the case of viscose rayon) or complex (e.g.cuprammonium rayon). For the purposes of this paper, advanced cellulosic fibres aredefined as those made from a process involving direct dissolution of cellulose. The firstexamples of such fibres have now been generically designaed as lyocel...

  3. 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.

  4. Alteration of in vivo cellulose ribbon assembly by carboxymethylcellulose and other cellulose derivatives

    OpenAIRE

    1982-01-01

    In vivo cellulose ribbon assembly by the Gram-negative bacterium Acetobacter xylinum can be altered by incubation in carboxymethylcellulose (CMC), a negatively charged water-soluble cellulose derivative, and also by incubation in a variety of neutral, water-soluble cellulose derivatives. In the presence of all of these substituted celluloses, normal fasciation of microfibril bundles to form the typical twisting ribbon is prevented. Alteration of ribbon assembly is most extensive in the presen...

  5. Batch and Fed-Batch Fermentation System on Ethanol Production from Whey using Kluyveromyces marxianus

    Directory of Open Access Journals (Sweden)

    H Hadiyanto

    2013-10-01

    Full Text Available Nowadays reserve of fossil fuel has gradually depleted. This condition forces many researchers to  find energy alternatives which is renewable and sustainable in the future. Ethanol derived from cheese industrial waste (whey using fermentation process can be a new perspective in order to secure both energy and environment. The aim of this study was  to compare the operation modes (batch and fed-batch of fermentation system on ethanol production from whey using Kluyveromyces marxianus. The result showed that the fermentation process for ethanol production by fed-batch system was higher at some point of parameters compared with batch system. Growth rate and ethanol yield (YP/S of fed-batch fermentation were 0.122/h and 0.21 gP/gS respectively; growth rate and ethanol yield (YP/S of batch fermentation were 0.107/h, and 0.12 g ethanol/g substrate, respectively. Based on the data of biomass and ethanol concentrations, the fermentation process for ethanol production by fed-batch system were higher at some point of parameters compared to batch system. Periodic substrate addition performed on fed-batch system leads the yeast growth in low substrate concentrations and consequently  increasing their activity and ethanol productivity. Keywords: batch; ethanol; fed-batch; fermentation;Kluyveromyces marxianus, whey

  6. Observational constraints on the global atmospheric budget of ethanol

    Directory of Open Access Journals (Sweden)

    V. Naik

    2010-01-01

    Full Text Available Energy security and climate change concerns have led to the promotion of biomass-derived ethanol, an oxygenated volatile organic compound (OVOC, as a substitute for fossil fuels. Although ethanol is ubiquitous in the troposphere, our knowledge of its current atmospheric budget and distribution is limited. Here, for the first time we use a global chemical transport model in conjunction with atmospheric observations to place constraints on the ethanol budget, noting that additional measurements of ethanol (and its precursors are still needed to enhance confidence in our estimated budget. Global sources of ethanol in the model include 5.0 Tg yr−1 from industrial sources and biofuels, 9.2 Tg yr−1 from terrestrial plants, ~0.5 Tg yr−1 from biomass burning, and 0.05 Tg yr−1 from atmospheric reactions of the ethyl peroxide radical (C2H5O2 with itself and with the methyl peroxide radical (CH3O2. The resulting atmospheric lifetime of ethanol in the model is 2.8 days. Gas-phase oxidation by hydroxyl radical (OH is the primary global sink of ethanol in the model (65%, followed by dry deposition to land (25%, and wet deposition (10%. Over continental areas, ethanol concentrations predominantly reflect direct anthropogenic and biogenic emission sources. Uncertainty in the biogenic ethanol emissions estimated at a factor of three may contribute to the 50% model underestimate of observations in the North American boundary layer. Furthermore, current levels of ethanol measured in remote atmospheres are an order of magnitude larger than those explained by surface sources or by in-situ atmospheric production from observed precursor hydrocarbons in the model, suggesting a major gap in understanding. Stronger constraints on the budget and distribution of ethanol and other VOCs are a critical step towards assessing the impacts of increasing use of ethanol as a

  7. Life cycle cost of ethanol production from cassava in Thailand

    International Nuclear Information System (INIS)

    To increase the security of energy supply, lessen dependence on crude oil import and buffer against the impacts of large change in crude oil prices, the Thai government initiated and officially announced the national ethanol fuel program in year 2000. Since then, domestic ethanol demand has grown rapidly. Presently, all commercial ethanol in Thailand is produced from molasses as Thai law prohibits producing it from sugar cane directly. This is likely to limit ethanol supply in the near future. One possible solution is to supply more ethanol from cassava which is widely cultivated in this country. However, its production cost has not yet been known for certain. The objective of this study is to estimate the life cycle cost of ethanol production from cassava and to assess its economic competitiveness with gasoline in the Thai fuel market. Based on the record of cassava prices during the years 2002-2005, it was found that using it as feedstock would share more than 50% of the ethanol from cassava total production cost. It was also found that a bio-ethanol plant, with a capacity of 150,000 l/day, can produce ethanol from cassava in a range of ex-factory costs from 16.42 to 20.83 baht/l of gasoline equivalent (excluding all taxes), with an average cost of 18.15 baht/l of gasoline equivalent (41, 52 and 45 US cents/l gasoline equivalent respectively, based on 2005 exchange rate). In the same years, the range of 95-octane gasoline prices in Thailand varied from 6.18 baht to 20.86 baht/l, with an average price of 11.50 baht/l (15, 52 and 29 US cents/l respectively, based on 2005 exchange rate) which were much cheaper than the costs of ethanol made from cassava. Thus, we conclude that under the scenario of low to normal crude oil price, ethanol from cassava is not competitive with gasoline. The gasoline price has to rise consistently above 18.15 baht (45 US cents)/l before ethanol made from cassava can be commercially competitive with gasoline. (author)

  8. Life cycle cost of ethanol production from cassava in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Sorapipatana, Chumnong; Yoosin, Suthamma [Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Pracha-Uthit Rd., Tungkru, Bangmod, Bangkok 10140 (Thailand); Center for Energy Technology and Environment, Commission on Higher Education, Ministry of Education, Bangkok (Thailand)

    2011-02-15

    To increase the security of energy supply, lessen dependence on crude oil import and buffer against the impacts of large change in crude oil prices, the Thai government initiated and officially announced the national ethanol fuel program in year 2000. Since then, domestic ethanol demand has grown rapidly. Presently, all commercial ethanol in Thailand is produced from molasses as Thai law prohibits producing it from sugar cane directly. This is likely to limit ethanol supply in the near future. One possible solution is to supply more ethanol from cassava which is widely cultivated in this country. However, its production cost has not yet been known for certain. The objective of this study is to estimate the life cycle cost of ethanol production from cassava and to assess its economic competitiveness with gasoline in the Thai fuel market. Based on the record of cassava prices during the years 2002-2005, it was found that using it as feedstock would share more than 50% of the ethanol from cassava total production cost. It was also found that a bio-ethanol plant, with a capacity of 150,000 l/day, can produce ethanol from cassava in a range of ex-factory costs from 16.42 to 20.83 baht/l of gasoline equivalent (excluding all taxes), with an average cost of 18.15 baht/l of gasoline equivalent (41, 52 and 45 US cents/l gasoline equivalent respectively, based on 2005 exchange rate). In the same years, the range of 95-octane gasoline prices in Thailand varied from 6.18 baht to 20.86 baht/l, with an average price of 11.50 baht/l (15, 52 and 29 US cents/l respectively, based on 2005 exchange rate) which were much cheaper than the costs of ethanol made from cassava. Thus, we conclude that under the scenario of low to normal crude oil price, ethanol from cassava is not competitive with gasoline. The gasoline price has to rise consistently above 18.15 baht (45 US cents)/l before ethanol made from cassava can be commercially competitive with gasoline. (author)

  9. Financial security

    NARCIS (Netherlands)

    M. de Goede

    2010-01-01

    1. Introduction J. Peter Burgess Part 1: New Security Concepts 2. Civilizational Security Brett Bowden 3. Risk Oliver Kessler 4. Small Arms Keith Krause 5. Critical Human Security Taylor Owen 6. Critical Geopolitics Simon Dalby Part 2: New Security Subjects 7. Biopolitics Michael Dillon 8. Gendered

  10. Cyber security

    CERN Document Server

    Voeller, John G

    2014-01-01

    Cyber Security features articles from the Wiley Handbook of Science and Technology for Homeland Security covering topics related to cyber security metrics and measure  and related technologies that meet security needs. Specific applications to web services, the banking and the finance sector, and industrial process control systems are discussed.

  11. Improved Cellulose and Organic-Solvents based Lignocellulosic Fractionation Pre-treatment of Organic Waste for Bioethanol Production

    OpenAIRE

    Valeriy Bekmuradov; Grace Luk; Robin Luong

    2014-01-01

    This study investigates the performance of the Cellulose and Organic-Solvents based Lignocellulosic Fractionation (COSLIF) method for the pretreatment of Source-Separated Organic (SSO) waste. An improvement on the standard method of COSLIF pre-treatment was developed based on lower enzyme loading and using an ethanol washing instead of acetone. It was demonstrated that a much higher glucose yield (90% after 72 hours) was possible with this improvement, as compared to the original method, w...

  12. LTE security

    CERN Document Server

    Forsberg, Dan; Moeller, Wolf-Dietrich

    2010-01-01

    Addressing the security solutions for LTE, a cellular technology from Third Generation Partnership Project (3GPP), this book shows how LTE security substantially extends GSM and 3G security. It also encompasses the architectural aspects, known as SAE, to give a comprehensive resource on the topic. Although the security for SAE/LTE evolved from the security for GSM and 3G, due to different architectural and business requirements of fourth generation systems the SAE/LTE security architecture is substantially different from its predecessors. This book presents in detail the security mechanisms em

  13. Sulfuric Acid Pretreatment and Enzymatic Hydrolysis of Photoperiod Sensitvie Sorghum for Ethanol Production

    Energy Technology Data Exchange (ETDEWEB)

    F Xu; Y Shi; X Wu

    2011-12-31

    Photoperiod sensitive (PS) sorghum, with high soluble sugar content, high mass yield and high drought tolerance in dryland environments, has great potential for bioethanol production. The effect of diluted sulfuric acid pretreatment on enzymatic hydrolysis was investigated. Hydrolysis efficiency increased from 78.9 to 94.4% as the acid concentration increased from 0.5 to 1.5%. However, the highest total glucose yield (80.3%) occurred at the 1.0% acid condition because of the significant cellulose degradation at the 1.5% concentration. Synchrotron wide-angle X-ray diffraction was used to study changes of the degree of crystallinity. With comparison of cellulosic crystallinity and adjusted cellulosic crystallinity, the crystalline cellulose decreased after low acidic concentration (0.5%) applied, but did not change significantly, as the acid concentration increased. Scanning electron microscopy was also employed to understand how the morphological structure of PS sorghum changed after pretreatment. Under current processing conditions, the total ethanol yield is 74.5% (about 0.2 g ethanol from 1 g PS sorghum). A detail mass balance was also provided.

  14. Cytocompatible cellulose hydrogels containing trace lignin.

    Science.gov (United States)

    Nakasone, Kazuki; Kobayashi, Takaomi

    2016-07-01

    Sugarcane bagasse was used as a cellulose resource to prepare transparent and flexible cellulose hydrogel films. On the purification process from bagasse to cellulose, the effect of lignin residues in the cellulose was examined for the properties and cytocompatibility of the resultant hydrogel films. The cellulose was dissolved in lithium chloride/N,N-dimethylacetamide solution and converted to hydrogel films by phase inversion. In the purification process, sodium hydroxide (NaOH) treatment time was changed from 1 to 12h. This resulted in cellulose hydrogel films having small amounts of lignin from 1.62 to 0.68%. The remaining lignin greatly affected hydrogel properties. Water content of the hydrogel films was increased from 1153 to 1525% with a decrease of lignin content. Moreover, lower lignin content caused weakening of tensile strength from 0.80 to 0.43N/mm(2) and elongation from 45.2 to 26.5%. Also, similar tendency was observed in viscoelastic behavior of the cellulose hydrogel films. Evidence was shown that the lignin residue was effective for the high strength of the hydrogel films. In addition, scanning probe microscopy in the morphological observation was suggested that the trace lignin in the cellulose hydrogel affected the cellulose fiber aggregation in the hydrogel network. The trace of lignin in the hydrogels also influenced fibroblast cell culture on the hydrogel films. The hydrogel film containing 1.68% lignin showed better fibroblast compatibility as compared to cell culture polystyrene dish used as reference. PMID:27127053

  15. Carboxymethylation of Cellulose by Microwave irradiation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Cellulose may be readily converted into ethers involving primary and secondary alcohol groups in each monomer unit and the glycosidic bonds. However, these reactions are rather more complicated than with simple substances, because the stereochemistry of the cellulose molecule is such that the vast majority of its hydroxyl groups form intra-chain hydrogen bonds or inter-chain hydrogen bonds with contiguous molecules. Carboxymethylcellulose (CMC) has played an important part in the commercial uses of cellulose derivatives. CMC becomes alkali and water soluble. The polarity can, in fact, be increased by introduction of ionizing groups, ie carboxymethyl group. CMC is generally produced by the reaction of alkali cellulose with chloroacetic acid.

  16. 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.)

  17. Enzymatic Hydrolysis Optimization to Ethanol Production by Simultaneous Saccharification and Fermentation

    Science.gov (United States)

    Vásquez, Mariana Peñuela; da Silva, Juliana Nascimento C.; de Souza, Maurício Bezerra; Pereira, Nei

    There is tremendous interest in using agro-industrial wastes, such as cellulignin, as starting materials for the production of fuels and chemicals. Cellulignin are the solids, which result from the acid hydrolysis of the sugarcane bagasse. The objective of this work was to optimize the enzymatic hydrolysis of the cellulose fraction of cellulignin, and to study its fermentation to ethanol using Saccharomyces cerevisiae. Cellulose conversion was optimized using response surface methods with pH, enzyme loading, solid percentage, and temperature as factor variables. The optimum conditions that maximized the conversion of cellulose to glucose, calculated from the initial dried weight of pretreated cellulignin, (43°C, 2%, and 24.4 FPU/g of pretreated cellulignin) such as the glucose concentration (47°C, 10%, and 25.6 FPU/g of pretreated cellulignin) were found. The desirability function was used to find conditions that optimize both, conversion to glucose and glucose concentration (47°C, 10%, and 25.9 FPU/g of pretreated cellulignin). The resulting enzymatic hydrolyzate was fermented yielding a final ethanol concentration of 30.0 g/L, in only 10 h, and reaching a volumetric productivity of 3.0 g/L·h, which is close to the values obtained in the conventional ethanol fermentation of sugar cane juice (5.0-8.0 g/L·h) in Brazil.

  18. Preparation for commercial demonstration of biomass-to-ethanol conversion technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The objective of this program was to complete the development of a commercially viable process to produce fuel ethanol from renewable cellulosic biomass. The program focused on pretreatment, enzymatic hydrolysis, and fermentation technologies where Amoco has a unique proprietary position. Assured access to low-cost feedstock is a cornerstone of attractive economics for cellulose to ethanol conversion in the 1990s. Most of Amoco`s efforts in converting cellulosic feedstocks to ethanol before 1994 focused on using paper from municipal solid waste as the feed. However, while many municipalities and MSW haulers expressed interest in Amoco`s technology, none were willing to commit funding to process development. In May, 1994 several large agricultural products companies showed interest in Amoco`s technology, particularly for application to corn fiber. Amoco`s initial work with corn fiber was encouraging. The project work plan was designed to provide sufficient data on corn fiber conversion to convince a major agriculture products company to participate in the construction of a commercial demonstration facility.

  19. Simultaneous cellulose conversion and hydrogen production assisted by cellulose decomposition under UV-light photocatalysis

    OpenAIRE

    Zhang, Guan; Ni, Chengsheng; Huang, Xiubing; Welgamage, Aakash; Lawton, Linda A.; Robertson, Peter K. J.; Irvine, John T. S.

    2016-01-01

    Photocatalytic conversion of cellulose to sugars and carbon dioxide with simultaneous production of hydrogen assisted by cellulose decomposition under UV or solar light irradiation was achieved upon immobilization of cellulose onto a TiO2 photocatalyst. This approach enables production of hydrogen from water without using valuable sacrificial agents, and provides the possibility for recovering sugars as liquid fuels.

  20. Simultaneous cellulose conversion and hydrogen production assisted by cellulose decomposition under UV-light photocatalysis.

    Science.gov (United States)

    Zhang, Guan; Ni, Chengsheng; Huang, Xiubing; Welgamage, Aakash; Lawton, Linda A; Robertson, Peter K J; Irvine, John T S

    2016-01-28

    Photocatalytic conversion of cellulose to sugars and carbon dioxide with simultaneous production of hydrogen assisted by cellulose decomposition under UV or solar light irradiation was achieved upon immobilization of cellulose onto a TiO2 photocatalyst. This approach enables production of hydrogen from water without using valuable sacrificial agents, and provides the possibility for recovering sugars as liquid fuels. PMID:26661296

  1. Effect of Organic Acids on Bacterial Cellulose Produced by Acetobacter xylinum

    Directory of Open Access Journals (Sweden)

    Hongmei Lu

    2016-03-01

    Full Text Available Based on the difference of bacterial cellulose production from rice saccharificate medium and chemical medium under static cultivation, effect of organic acids in the process of bacterial cellulose produced by A. xylinum was studied. The results showed that the kinds and contents of organic acids were different in both culture medium, in which accumulated oxalic acid and tartaric acid inhibited A. xylinum producing BC in chemical medium, while pyruvic acid, malic acid, lactic acid, acetic acid, citric acid and succinic acid, as ethanol, promoted A. xylinum to produce BC. Compared to the blank BC production 1.48 g/L, the optimum addition concentrations of pyruvic acid, malic acid, lactic acid, acetic acid, citric acid, succinic acid, and ethanol in chemical medium were 0.15%, 0.1%, 0.3%, 0.4%, 0.1%, 0.2% , 4% and the BC productions were 2.49 g/L, 2.83 g/L, 2.12 g/L, 2.54 g/L, 2.27 g/L, 1.88 g/L , 2.63 g/L, respectively. The co-existence of above organic acids and ethanol increased BC production even further.

  2. 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

  3. 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

  4. An economic comparison of different fermentation configurations to convert corn stover to ethanol using Z. mobilis and Saccharomyces.

    Science.gov (United States)

    Dutta, Abhijit; Dowe, Nancy; Ibsen, Kelly N; Schell, Daniel J; Aden, Andy

    2010-01-01

    Numerous routes are being explored to lower the cost of cellulosic ethanol production and enable large-scale production. One critical area is the development of robust cofermentative organisms to convert the multiple, mixed sugars found in biomass feedstocks to ethanol at high yields and titers without the need for processing to remove inhibitors. Until such microorganisms are commercialized, the challenge is to design processes that exploit the current microorganisms' strengths. This study explored various process configurations tailored to take advantage of the specific capabilities of three microorganisms, Z. mobilis 8b, S. cerevisiae, and S. pastorianus. A technoeconomic study, based on bench-scale experimental data generated by integrated process testing, was completed to understand the resulting costs of the different process configurations. The configurations included whole slurry fermentation with a coculture, and separate cellulose simultaneous saccharification and fermentation (SSF) and xylose fermentations with none, some or all of the water to the SSF replaced with the fermented liquor from the xylose fermentation. The difference between the highest and lowest ethanol cost for the different experimental process configurations studied was $0.27 per gallon ethanol. Separate fermentation of solid and liquor streams with recycle of fermented liquor to dilute the solids gave the lowest ethanol cost, primarily because this option achieved the highest concentrations of ethanol after fermentation. Further studies, using methods similar to ones employed here, can help understand and improve the performance and hence the economics of integrated processes involving enzymes and fermentative microorganisms. PMID:19785041

  5. 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 on...... Ni-based catalysts during SR of ethanol were investigated in a flow reactor. Four different supports for Ni were tested and Ce0.6Zr0.4O2 showed the highest activity, but also suffered from severe carbon deposition at 600 °C or below. Operation at 600 °C or above were needed for full conversion of...... ethanol over the most active catalysts at the applied conditions. At these temperatures the offgas composition was close to the thermodynamical equilibrium. Operation at high temperatures, 700 °C and 750 °C, gave the lowest carbon deposition corresponding to 30–60 ppm of the carbon in the feed ending as...

  6. Xylose fermentation to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    McMillan, J.D.

    1993-01-01

    The past several years have seen tremendous progress in the understanding of xylose metabolism and in the identification, characterization, and development of strains with improved xylose fermentation characteristics. A survey of the numerous microorganisms capable of directly fermenting xylose to ethanol indicates that wild-type yeast and recombinant bacteria offer the best overall performance in terms of high yield, final ethanol concentration, and volumetric productivity. The best performing bacteria, yeast, and fungi can achieve yields greater than 0.4 g/g and final ethanol concentrations approaching 5%. Productivities remain low for most yeast and particularly for fungi, but volumetric productivities exceeding 1.0 g/L-h have been reported for xylose-fermenting bacteria. In terms of wild-type microorganisms, strains of the yeast Pichia stipitis show the most promise in the short term for direct high-yield fermentation of xylose without byproduct formation. Of the recombinant xylose-fermenting microorganisms developed, recombinant E. coli ATTC 11303 (pLOI297) exhibits the most favorable performance characteristics reported to date.

  7. Innovative inexpensive ethanol

    International Nuclear Information System (INIS)

    New Energy Company of Indiana which produces 70 million gallons of ethanol per year, avoids the headaches often associated with organic by-products by creating an efficient and profitable sideline business. This paper reports that stretching across 55 acres in South Bend, Ind., New Energy's plant is the largest in the U.S. built specifically for fuel alcohol. The $186-million complex is a dramatic advance in the art of producing ethanol and its co-products. As the demand grows in the coming years for fuel alcohol-proven as an octane booster and a clean-burning alternative fuel. New Energy looks forward to increase production and profits. At the company's six-year-old plant, fuel alcohol is made from 26 million bushels a year of No. 2 yellow dent corn. Left at the bottom of the first column, after the alcohol has been boiled off, is stillage that contains more than 90% of the corn's protein and fat content, and virtually all of its vitamins and minerals, along with the yeast used to make the ethanol. While technically a waste product of the fuel alcohol process, this material's quantity and organic content not only make it difficult and costly to dispose, but its nutritional quality makes it an excellent candidate to be further processed into animal feed

  8. Bioconversion of different sizes of microcrystalline cellulose pretreated by microwave irradiation with/without NaOH

    International Nuclear Information System (INIS)

    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 (RDS), 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

  9. Development of Cellulose/PVDF-HFP Composite Membranes for Advanced Battery Separators

    Science.gov (United States)

    Castillo, Alejandro; Agubra, Victor; Alcoutlabi, Mataz; Mao, Yuanbing

    Improvements in battery technology are necessary as Li-ion batteries transition from consumer electronic to vehicular and industrial uses. An important bottle-neck in battery efficiency and safety is the quality of the separators, which prevent electric short-circuits between cathode and anode, while allowing an easy flow of ions between them. In this study, cellulose acetate was dissolved in a mixed solvent with poly(vinylpyrrolidone) (PVP), and the mixture was forcespun in a peudo paper making process to yield nanofibrillated nonwoven mats. The mats were soaked in NaOH/Ethanol to strip PVP and regenerate cellulose from its acetate precursor. The cellulose mats were then dipped in poly(vinylidenefluoride-co-hexafluoropropylene) (PVDF-HFP) to yield the cellulose/PVDF-HFP composte membranes. These membranes were characterized chemically through FTIR spectroscopy and solvent-stability tests, thermally through DSC, physically by stress/strain measurements along with weight-based electrolyte uptake, and electrically by AC-impedance spectroscopy combined with capacitative cycling.

  10. 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

  11. Improvement of the ESR detection of irradiated food containing cellulose employing a simple extraction method

    International Nuclear Information System (INIS)

    Fruit may be irradiated at rather low doses, below 1 kGy in combination treatments or for quarantine purposes. To improve the ESR detection sensitivity of irradiated fruit de Jesus et al. (Int. J. Food Sci. Technol. 34 (1999) 173.) proposed extracting the fruit pulp with 80% ethanol and measuring the residue with ESR using low power (0.25 mW) for detection of 'cellulosic' radicals. An improvement in ESR sensitivity using the extraction procedure could be confirmed in this paper for strawberries and papayas. In most cases, a radiation dose of 0.5 kGy could be detected in both fruits even after 2-3 weeks storage. In addition, some herbs and spices were also tested, but only for a few of them the ESR detection of the 'cellulosic' signal was improved by previous alcoholic extraction. As an alternative to ESR measurements, other detection methods like DNA Comet Assay and thermoluminescence were also tested

  12. Security Expertise

    DEFF Research Database (Denmark)

    This volume brings together scholars from different fields to explore the power, consequences and everyday practices of security expertise. Expertise mediates between different forms of knowledge: scientific and technological, legal, economic and political knowledge. This book offers the first...... systematic study of security expertise and opens up a productive dialogue between science and technology studies and security studies to investigate the character and consequences of this expertise. In security theory, the study of expertise is crucial to understanding whose knowledge informs security making...... and to reflect on the impact and responsibility of security analysis. In science and technology studies, the study of security politics adds a challenging new case to the agenda of research on expertise and policy. The contributors investigate cases such as academic security studies, security think...

  13. 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.

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

    International Nuclear Information System (INIS)

    Highlights: • High solids (30% dry matter) pretreatment, enzymatic hydrolysis and fermentation. • Horizontal rotary reactor for hydrolysis and fermentation. • In situ hydrolysates detoxification using inhibitors adsorbing PEI polymer. • 50% of inhibitors recovered as by-product, recyclability of PEI polymer up to 5 times. • 76% of maximum theoretical ethanol was fermented at final concentration of 51 g/kg. - Abstract: Performing the bioethanol production process at high solids loading is a requirement for economic feasibility at industrial scale. So far this has successfully been achieved using wheat straw and other agricultural residues at 30% of water insoluble solids (WIS), but for softwood species (i.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 ∼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 polyelectrolyte polymer (polyethylenimine, PEI) to absorb inhibitory compounds in the material. On average 50% removal and recovery of the main inhibitors (HMF, furfural, acetic acid and formic acid) was achieved dosing 1.5% w/w of soluble PEI. The use of PEI was compatible with operating the process at high solids loadings and enabled fermentation of hydrolysates, which

  15. [Audiometry in the cellulose industry].

    Science.gov (United States)

    Corrao, C R; Milano, L; Pedulla, P; Carlesi, G; Bacaloni, A; Monaco, E

    1993-01-01

    A noise level dosimetry and audiometric testing were conducted in a cellulose factory to determine the hazardous noise level and the prevalence of noise induced hearing loss among the exposed workers. The noise level was recorded up to 90 db (A) in several working areas. 18 workers, potentially exposed to noise injury, evidenced a significant hearing loss. While no evidence of noise injury was recorded in a control group of 100 subjects. This finding suggest a strict relationship between audiometric tests, the noise level recorded in the working place and the working seniority of exposed employers. PMID:7720969

  16. A Sustainable Ethanol Distillation System

    Directory of Open Access Journals (Sweden)

    Yuelei Yang

    2012-01-01

    Full Text Available The discarded fruit and vegetable waste from the consumer and retailer sectors provide a reliable source for ethanol production. In this paper, an ethanol distillation system has been developed to remove the water contents from the original wash that contains only around 15% of the ethanol. The system has an ethanol production capacity of over 100,000 liters per day. It includes an ethanol condenser, a wash pre-heater, a main exhaust heat exchanger as well as a fractionating column. One unique characteristic of this system is that it utilizes the waste heat rejected from a power plant to vaporize the ethanol, thus it saves a significant amount of energy and at the same time reduces the pollution to the environment.

  17. Rheological characterization of microcrystalline cellulose and silicified microcrystalline cellulose wet masses using a mixer torque rheometer.

    Science.gov (United States)

    Luukkonen, P; Schaefer, T; Hellén, L; Juppo, A M; Yliruusi, J

    1999-10-25

    The rheological properties of silicified microcrystalline cellulose (Prosolv 50) were compared with those of standard grades of microcrystalline cellulose (Emcocel 50 and Avicel PH 101). Cellulose samples were analyzed using nitrogen adsorption together with particle size, flowability, density and swelling volume studies. The rheological behaviour of the wet powder masses was studied as a function of mixing time using a mixer torque rheometer (MTR). Silicified microcrystalline cellulose exhibited improved flow characteristics and increased specific surface area compared to standard microcrystalline cellulose grades. Although the silicification process affected the swelling properties and, furthermore, the mixing kinetics of microcrystalline cellulose, the source of the microcrystalline cellulose had a stronger influence than silicification on the liquid requirement at peak torque. PMID:10518674

  18. Effect of rheological properties of dissolved cellulose/microfibrillated cellulose blend suspensions on film forming.

    Science.gov (United States)

    Saarikoski, Eve; Rissanen, Marja; Seppälä, Jukka

    2015-03-30

    Enzymatically treated cellulose was dissolved in a NaOH/ZnO solvent system and mixed together with microfibrillated cellulose (MFC) in order to find the threshold in which MFC fibers form a percolation network within the dissolved cellulose solution and in order to improve the properties of regenerated cellulose films. In the aqueous state, correlations between the rheological properties of dissolved cellulose/MFC blend suspensions and MFC fiber concentrations were investigated and rationalized. In addition, rheological properties of diluted MFC suspensions were characterized and a correlation with NaOH concentration was found, thus partly explaining the flow properties of dissolved cellulose/MFC blend suspensions. Finally, based on results from Dynamic Mechanical Analysis (DMA), MFC addition had strengthening/plasticizing effect on regenerated cellulose films if low concentrations of MFC, below the percolation threshold (5.5-6 wt%, corresponding to 0.16-0.18 wt% of MFC in the blend suspensions), were used. PMID:25563945

  19. Cellulose nanocrystals: synthesis, functional properties, and applications

    Directory of Open Access Journals (Sweden)

    George J

    2015-11-01

    Full Text Available Johnsy George, SN Sabapathi Food Engineering and Packaging Division, Defence Food Research Laboratory, Siddarthanagar, Mysore, Karnataka, India Abstract: Cellulose nanocrystals are unique nanomaterials derived from the most abundant and almost inexhaustible natural polymer, cellulose. These nanomaterials have received significant interest due to their mechanical, optical, chemical, and rheological properties. Cellulose nanocrystals primarily obtained from naturally occurring cellulose fibers are biodegradable and renewable in nature and hence they serve as a sustainable and environmentally friendly material for most applications. These nanocrystals are basically hydrophilic in nature; however, they can be surface functionalized to meet various challenging requirements, such as the development of high-performance nanocomposites, using hydrophobic polymer matrices. Considering the ever-increasing interdisciplinary research being carried out on cellulose nanocrystals, this review aims to collate the knowledge available about the sources, chemical structure, and physical and chemical isolation procedures, as well as describes the mechanical, optical, and rheological properties, of cellulose nanocrystals. Innovative applications in diverse fields such as biomedical engineering, material sciences, electronics, catalysis, etc, wherein these cellulose nanocrystals can be used, are highlighted. Keywords: sources of cellulose, mechanical properties, liquid crystalline nature, surface modification, nanocomposites 

  20. Canada's directory of ethanol retailers

    International Nuclear Information System (INIS)

    This document is a directory 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 by province from west to east. Appendices providing a list of bulk purchase facilities of ethanol-blended fuels was also included, as well as a list of ethanol-blended gasoline retailers

  1. Comparison of different pretreatment strategies for ethanol production of West African biomass.

    Science.gov (United States)

    Thomsen, Sune Tjalfe; Londoño, Jorge Enrique González; Schmidt, Jens Ejbye; Kádár, Zsófia

    2015-03-01

    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 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 of glucan (>30 g glucan per 100 g total solids (TS)). HTT did show better results in both enzymatic convertibility and fermentation, but evaluated on the overall ethanol yield the low-tech pretreatment methods are viable alternatives with similar levels to the HTT (13.4-15.2 g ethanol per 100 g TS raw material). PMID:25542239

  2. Improvement of ethanol production by ethanol-tolerant Saccharomyces cerevisiae UVNR56

    OpenAIRE

    Thammasittirong, Sutticha Na-Ranong; Thirasaktana, Thanawan; Thammasittirong, Anon; Srisodsuk, Malee

    2013-01-01

    Ethanol tolerance is one of the important characteristics of ethanol-producing yeast. This study focused on the improvement of ethanol tolerance of Saccharomyces cerevisiae NR1 for enhancing ethanol production by random UV-C mutagenesis. One ethanol-tolerant mutant, UVNR56, displayed a significantly improved ethanol tolerance in the presence of 15% (v/v) ethanol and showed a considerably higher viability during ethanol fermentation from sugarcane molasses and sugarcane molasses with initial e...

  3. Radiation pretreatment of cellulose for energy production

    Science.gov (United States)

    Dela Rosa, A. M.; Dela Mines, A. S.; Banzon, R. B.; Simbul-Nuguid, Z. F.

    The effect of radiation pretreatment of agricultural cellulosic wastes was investigated through hydrolytic reactions of cellulose. Gamma irradiation significantly increased the acid hydrolysis of rice straw, rice hull and corn husk. The yields of reducing sugar were higher with increasing radiation dose in these materials. The observed radiation effect varied with the cellulosic material but it correlated with neither the cellulose content nor the lignin content. Likewise, the radiation pretreatment accelerated the subsequent enzymatic hydrolysis of rice straw and rice hull by cellulase. The irradiated rice straw appeared to be a better growth medium for the cellulolytic microorganism, Myrothecium verrucaria, than the non-irradiated material. This was attributed to increased digestibility of the cellulose by the microorganism.

  4. Radiation pretreatment of cellulose for energy production

    International Nuclear Information System (INIS)

    The effect of radiation pretreatment of agricultural cellulosic wastes was investigated through hydrolytic reactions of cellulose. Gamma irradiation significantly increased the acid hydrolysis of rice straw, rice hull and corn husk. The yields of reducing sugar were higher with increasing radiation dose in these materials. The observed radiation effect varied with the cellulose material but it correlated with neither the cellulose content nor the lignin content. Likewise, the radiation pretreatment accelerated the subsequent enzymatic hydrolysis of rice straw and rice hull by cellulase. The irradiated rice straw appeared to be a better growth medium for the cellulolytic microorganism, Myrothecium verrucaria, than the non-irradiated material. This was attributed to increased digestibility of the cellulose by the microorganism. (author)

  5. Single-cell protein from waste cellulose

    Science.gov (United States)

    Dunlap, C. E.; Callihan, C. D.

    1973-01-01

    The recycle, reuse, or reclamation of single cell protein from liquid and solid agricultural waste fibers by a fermentation process is reported. It is shown that cellulose comprises the bulk of the fibers at 50% to 55% of the dry weight of the refuse and that its biodegradability is of prime importance in the choice of a substrate. The application of sodium hydroxide followed by heat and pressure serves to de-polymerize and disrupt lignin structure while swelling the cellulose to increase water uptake and pore volume. Some of the lignin, hemi-celluloses, ash, and cellulose of the material is hydrolized and solubilized. Introduction of microorganisms to the substrate fibers mixed with nutrients produces continuous fermentation of cellulose for further protein extraction and purification.

  6. Photophysics of alloxazines on cellulose.

    Science.gov (United States)

    Sikorski, Marek; Sikorska, Ewa; Khmelinskii, Igor V; Gonzalez-Moreno, Rafael; Bourdelande, José L; Siemiarczuk, Aleksander

    2002-09-01

    We report the UV-Vis absorption, fluorescence and transient absorption spectra of selected methylalloxazines adsorbed on cellulose from a polar solvent. The ground-state properties of these probe molecules in the cellulose matrix are similar to those in polar protic solvents. Fluorescence decay data allowed identification of three emitting species for every molecule studied, excluding 1-methyllumichrome which lacks the capacity to rearrange into an isoalloxazinic form. The short-lived emission component was attributed to the neutral form of the molecule, and the two longer-lived components were assigned to the two distinct deprotonated monoanionic forms resulting from dissociation at the respective N(3) and N(1) nitrogen atoms. The two monoanions coexist due to their very similar pKa, values. Transient absorption experiments detected two species created by the laser pulse in these systems. The short-lived species was identified as the triplet excited state, and the long-lived species as the semireduced radical, formed by hydrogen atom or proton transfer from the glycosidic unit to the alloxazine carbonyl group. PMID:12665311

  7. Anaerobic digestion of cellulosic wastes

    International Nuclear Information System (INIS)

    Anaerobic digestion is a potentially attractive technology for volume reduction of low-level radioactive cellulosic wastes. A substantial fraction of the waste is converted to off-gas and a relatively small volume of biologically stabilized sludge is produced. Process development work has been completed using a 75-L digester to verify rates and conversions obtained at the bench scale. Start-up and operating procedures have been developed, and effluent was generated for characterization and disposal studies. Three runs using batch and fed-batch conditions were made lasting 36, 90, and 423 d. Solids solubilization rates and gas production rates averaged approximately 1.8 g cellulose per L of reactor per d and 1.2 L of off-gas per L reactor per d. Greater than 80% destruction of the volatile suspended solids was obtained. A simple dynamic process model was constructed to aid in process design and for use in process monitoring and control of a large-scale digester

  8. Anaerobic digestion of cellulosic wastes

    International Nuclear Information System (INIS)

    Anaerobic digestion is a potentially attractive technology for volume reduction of cellulosic wastes. A substantial fraction of the waste is converted to off-gas and a relatively small volume of biologically stabilized sludge is produced. Process development work is underway using a 75-L digester to verify rates and conversions obtained at the bench scale, to develop start-up and operating procedures, and to generate effluent for characterization and disposal studies. Three runs using batch and batch-fed conditions have been made lasting 36, 90, and over 200 days. Solids solubilization and gas production rates and total solids destruction have met or exceeded the target values of 0.6 g cellulose per L of reactor per day, 0.5 L off-gas per L of reactor per day, and 80% destruction of solids, respectively. Successful start-up procedures have been developed, and preliminary effluent characterization and disposal studies have been done. A simple dynamic process model has been constructed to aid in further process development and for use in process monitoring and control of a large-scale digester. 7 references, 5 figures, 1 table

  9. DESIGN DEVELOPMENT AND EVALUATION OF MODIFIED RELEASE TABLET OF MONTELUKAST SODIUM USING ETHYL CELLULOSE AND TRAGACANTH

    Directory of Open Access Journals (Sweden)

    Patel Krunal M

    2011-01-01

    Full Text Available The purpose of this research was to prepare a modified release tablet of montelukast sodium. Montelukast sodium is Leukotriene antagonist which is rapidly absorbed after the oral administration. The drug was mixed with Ethyl Cellulose and Tragacanth as a dry binder and ethanol was used as solvent to perform the granulation in FBD by the bottom spray method. The granules obtain were mixed with the other ingredients and were compressed using 10 station tablet rotary press. The dissolution was carried out using USP paddle apparatus.

  10. Usage of Cellulose Diacetate as Sorption Material for Fluorescent Analysis of PAH

    Directory of Open Access Journals (Sweden)

    Tamara I. Gubina

    2014-09-01

    Full Text Available Solid-phase matrices made of cellulose diacetate (CDA as films and fibers were prepared. The CDA film matrices were found to be characterized by a negative value of the surface potential (–32 ± 2 mV while the fibers had positive ones (+419 ± 1 mV. The possibility of using these matrices as sorption materials for luminescence analysis of polycyclic hydrocarbons in water-ethanol and micellar media is shown. Modification of such polymeric CDA matrices with surfactants of various natures improves their sorptive capacity and hydrocarbon recovery, and increases the sensitivity of luminescent analysis.

  11. A lignocellulosic ethanol strategy via nonenzymatic sugar production: process synthesis and analysis.

    Science.gov (United States)

    Han, Jeehoon; Luterbacher, Jeremy S; Alonso, David Martin; Dumesic, James A; Maravelias, Christos T

    2015-04-01

    The work develops a strategy for the production of ethanol from lignocellulosic biomass. In this strategy, the cellulose and hemicellulose fractions are simultaneously converted to sugars using a γ-valerolactone (GVL) solvent containing a dilute acid catalyst. To effectively recover GVL for reuse as solvent and biomass-derived lignin for heat and power generation, separation subsystems, including a novel CO2-based extraction for the separation of sugars from GVL, lignin and humins have been designed. The sugars are co-fermented by yeast to produce ethanol. Furthermore, heat integration to reduce utility requirements is performed. It is shown that this strategy leads to high ethanol yields and the total energy requirements could be satisfied by burning the lignin. The integrated strategy using corn stover feedstock leads to a minimum selling price of $5 per gallon of gasoline equivalent, which suggests that it is a promising alternative to current biofuels production approaches. PMID:25704099

  12. Improvement of cellulose catabolism in Clostridium cellulolyticum by sporulation abolishment and carbon alleviation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yongchao [ORNL; Xu, Tao [University of Oklahoma, Norman; Tschaplinski, Timothy J [ORNL; Engle, Nancy L [ORNL; Graham, David E [ORNL; He, Zhili [University of Oklahoma, Norman; Zhou, Jizhong [University of Oklahoma, Norman

    2014-01-01

    Background Clostridium cellulolyticum can degrade lignocellulosic biomass, and ferment the soluble sugars to produce valuable chemicals such as lactate, acetate, ethanol and hydrogen. However, the cellulose utilization efficiency of C. cellulolyticum still remains very low, impeding its application in consolidated bioprocessing for biofuels production. In this study, two metabolic engineering strategies were exploited to improve cellulose utilization efficiency, including sporulation abolishment and carbon overload alleviation. Results The spo0A gene at locus Ccel_1894, which encodes a master sporulation regulator was inactivated. The spo0A mutant abolished the sporulation ability. In a high concentration of cellulose (50 g/l), the performance of the spo0A mutant increased dramatically in terms of maximum growth, final concentrations of three major metabolic products, and cellulose catabolism. The microarray and gas chromatography mass spectrometry (GC-MS) analyses showed that the valine, leucine and isoleucine biosynthesis pathways were up-regulated in the spo0A mutant. Based on this information, a partial isobutanol producing pathway modified from valine biosynthesis was introduced into C. cellulolyticum strains to further increase cellulose consumption by alleviating excessive carbon load. The introduction of this synthetic pathway to the wild-type strain improved cellulose consumption from 17.6 g/l to 28.7 g/l with a production of 0.42 g/l isobutanol in the 50 g/l cellulose medium. However, the spo0A mutant strain did not appreciably benefit from introduction of this synthetic pathway and the cellulose utilization efficiency did not further increase. A technical highlight in this study was that an in vivo promoter strength evaluation protocol was developed using anaerobic fluorescent protein and flow cytometry for C. cellulolyticum. Conclusions In this study, we inactivated the spo0A gene and introduced a heterologous synthetic pathway to manipulate the stress

  13. Potential of thin stillage as a low-cost nutrient source for direct cellulose fermentation by Clostridium thermocellum

    Directory of Open Access Journals (Sweden)

    Rumana Islam

    2015-11-01

    Full Text Available Utilization of thin stillage (TS, derived from grain-based ethanol production, was investigated as an alternative source for microbial growth nutrients during direct conversion of cellulose by Clostridium thermocellum DSM 1237. Fermentation end-products synthesized by C. thermocellum grown on media prepared with various concentrations (50-400 g/L of TS were compared to those synthesized by C. thermocellum grown on reagent grade chemical (reference medium. Cell-growth in TS media, monitored with the aid of quantitative polymerase chain reactions (qPCR technique, showed prolonged growth with increasing TS concentration. Final fermentation end-product concentrations from TS media were comparable with those from the reference medium despite lower growth-rates. The volumetric H2 production generated by C. thermocellum grown with medium containing a low concentration (50 g/L of TS matched the volumetric H2 production by C. thermocellum grown in the reference medium, while higher concentrations (200 g/L of TS resulted in greater synthesis of ethanol. Supplementation of TS-media with Mg++ enhanced ethanol production, while hydrogen production remained unchanged. These results suggest that TS, an attractive source of low-cost nutrients, is capable of supporting the growth of C. thermocellum and that high concentrations of TS favor synthesis of ethanol over hydrogen from cellulose.

  14. System analyse cellulose ethanol in combines - Combustion characterisation of lignin from cellulose based ethanol production; Systemanalys foer cellulosabaserad etanol i kombinat - Foerbraenningskarakterisering av lignin fraan cellulosabaserad etanolproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Lindstedt, Jan; Wingren, Anders; Magnusson, Staffan; Wiinikka, Henrik; Westbom, Urban; Lidman, Marcus; Groenberg, Carola

    2012-02-15

    In this work 3 different hydrolysed lignin fractions produced from Sugarcane Bagasse, Spruce and Wheat Straw were burned in a 150 kW horizontal furnace equipped with a powder burner to assess the combustion behaviour of hydrolysed lignin fuels. The combustion experiments showed that the feeding properties of all three lignin fractions were better compared to ordinary wood powder

  15. Being Secure

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    As the world wrestles with challenges from nontraditional security threats, a new concept of security management is emerging Security has traditionally been seen as the means of defending a territory, primarily through the use of military power. However, as the world evolves through the process of globalization, so too does the concept of security. It now incorporates military, political, economic, societal and environmental issues, as well as the many links that bind them. Yet for most people in the wor...

  16. Watermarking security

    CERN Document Server

    Bas, Patrick; Cayre, François; Doërr, Gwenaël; Mathon, Benjamin

    2016-01-01

    This book explains how to measure the security of a watermarking scheme, how to design secure schemes but also how to attack popular watermarking schemes. This book gathers the most recent achievements in the field of watermarking security by considering both parts of this cat and mouse game. This book is useful to industrial practitioners who would like to increase the security of their watermarking applications and for academics to quickly master this fascinating domain.

  17. Securities lending

    OpenAIRE

    Paul C. Lipson; Sabel, Bradley K.; Frank M. Keane

    2012-01-01

    This paper, originally released in August 1989 as part of a Federal Reserve Bank of New York series on the U.S. securities markets, examines loans of Treasury and agency securities in the domestic market. It highlights some important institutional characteristics of securities loan transactions, in particular the common use of agents to arrange the terms of the loans. While we note that this characteristic sets securities lending apart from most repurchase agreement (repo) transactions, which...

  18. Node security

    CERN Document Server

    Barnes, Dominic

    2013-01-01

    A practical and fast-paced guide that will give you all the information you need to secure your Node applications.If you are a developer who wishes to secure your Node applications, whether you are already using Node Security in production, or are considering using it for your next project, then this book will enable you to ensure security of your applications. An understanding of JavaScript is a prerequisite, and some experience with Node is recommended, though not required.

  19. Recent trends in global production and utilization of bio-ethanol fuel

    International Nuclear Information System (INIS)

    Bio-fuels are important because they replace petroleum fuels. A number of environmental and economic benefits are claimed for bio-fuels. Bio-ethanol is by far the most widely used bio-fuel for transportation worldwide. Production of bio-ethanol from biomass is one way to reduce both consumption of crude oil and environmental pollution. Using bio-ethanol blended gasoline fuel for automobiles can significantly reduce petroleum use and exhaust greenhouse gas emission. Bio-ethanol can be produced from different kinds of raw materials. These raw materials are classified into three categories of agricultural raw materials: simple sugars, starch and lignocellulose. Bio-ethanol from sugar cane, produced under the proper conditions, is essentially a clean fuel and has several clear advantages over petroleum-derived gasoline in reducing greenhouse gas emissions and improving air quality in metropolitan areas. Conversion technologies for producing bio-ethanol from cellulosic biomass resources such as forest materials, agricultural residues and urban wastes are under development and have not yet been demonstrated commercially. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Arvaniti, E.

    2010-12-15

    Agricultural residues from rapeseed biodiesel industry (rapeseed cake, rape straw, crude glycerol), which represent the 82%wt. of the oilseed rape, currently have only low-grade applications in the market. For this, a scenario was built on exploiting qualities of rapeseed biodiesel residues for forming added-value products, and expanding and upgrading an existing biodiesel plant, to an oilseed rape biorefinery by 2020 in European ground. Selection of products was based on a technological feasibility study given the time frame, while priority was given to Low-Value-High-Volume readily marketed products, like production of energy and feed. Products selected except rapeseed biodiesel, were ethanol, biogas, enzymes energy, chemical building blocks, and superior quality animal fodder. The production lines were analyzed and prospects for 2020 were projected on a critical basis. Particular merit was given to two products, ethanol from cellulose, and cellulolytic enzymes from rape straw. Cellulosic ethanol from rape straw was optimized for all production steps, i.e. for thermo-chemical pretreatment, enzyme hydrolysis, and fermentation of C6 sugars. Thermo-chemical pretreatment was studied with Wet oxidation technique at different conditions of temperature, reaction time, and oxygen pressure, but also factors like pre-soaking straw in warm water, or recycling liquid were also studied. Wet oxidation has been extensively tested in the past for different substrates, and gives promising results with indicators that are important for cellulosic ethanol production; C6 sugars recovery, high digestibility for enzymes, and limited formed degradation products. Here, optimal pretreatment conditions for rape straw were first presoaking rape straw at 80 deg. C for 20 minutes, and then wet-oxidize with 12 bar of oxygen at 205 deg. C for 3 minutes. Recovery of cellulose and hemicellulose under these conditions was 105% and 106% respectively, while recovery of lignin was 86%. When this