Sample records for dephenolization
-
Bozkoyunlu, Gaye; Takaç, Serpil
2014-01-01
Olive mill wastewater (OMW) with total phenol (TP) concentration range of 300-1200 mg/L was treated with alginate-immobilized Rhodotorula glutinis cells in batch system. The effects of pellet properties (diameter, alginate concentration and cell loading (CL)) and operational parameters (initial TP concentration, agitation rate and reusability of pellets) on dephenolization of OMW were studied. Up to 87% dephenolization was obtained after 120 h biodegradations. The utilization number of pellets increased with the addition of calcium ions into the biodegradation medium. The overall effectiveness factors calculated for different conditions showed that diffusional limitations arising from pellet size and pellet composition could be neglected. Mass transfer limitations appeared to be more effective at high substrate concentrations and low agitation rates. The parameters of logistic model for growth kinetics of R. glutinis in OMW were estimated at different initial phenol concentrations of OMW by curve-fitting of experimental data with the model.
-
International Nuclear Information System (INIS)
Scoma, Alberto; Bertin, Lorenzo; Fava, Fabio
2013-01-01
The influence of Hydraulic Retention Time (HRT) on the performances of a recently developed biotechnological anaerobic acidogenic process fed with dephenolized Olive Mill Wastewater (OMW) was investigated. The study was carried out under mesophilic conditions in Packed Bed Biofilm Reactors (PBBRs), filled with ceramic cubes and inoculated with a characterized and acclimated acidogenic microbial consortium. The PBBRs were fed with a HRT of 7, 5, 3 or 1 day, which corresponded to Organic Loading Rates (OLRs) of about 5.5, 7.8, 12.9 and 38.8 g L −1 d −1 , respectively. A significant production of a H 2 -rich biogas was observed when shorter HRTs were applied: in particular, H 2 relative amount and productivity increased from 3% to 32% and from 0.20 to 6.10 dm 3 m −3 h −1 , respectively, by decreasing the HRT from 7 to 1 day. On the contrary, shorter HRTs turned into a lower accumulation of Volatile Fatty Acids (VFAs), whose highest amounts were found with HRTs of 7 and 5 days (about 18.4 and 19.7 g L −1 COD equivalents, respectively). The highest conversion yield of COD into VFAs (36%) was obtained with a HRT of 5 days, when VFAs represented about 78% of the effluent COD. HRT also influenced the composition of the VFA mixture: acetic, propionic and butyric acid were the most prominent VFAs, being their relative amounts higher when PBBRs were operated with shorter HRTs (up to 19, 12 and 42% of the whole mixture, respectively, when HRT was 1 day). -- Highlights: ► HRT affects the acidogenic digestion of dephenolized olive mill wastewater. ► A significant production of bioH 2 can be coupled to that of volatile fatty acids. ► Higher H 2 and lower VFA productions were obtained by shortening the HRT
-
Catalytic coal liquefaction with treated solvent and SRC recycle
Garg, Diwakar; Givens, Edwin N.; Schweighardt, Frank K.
1986-01-01
A process for the solvent refining of coal to distillable, pentane soluble products using a dephenolated and denitrogenated recycle solvent and a recycled, pentane-insoluble, solvent-refined coal material, which process provides enhanced oil-make in the conversion of coal.
-
Phenol oxidation of petrol refinery wastewater catalyzed by Laccase
International Nuclear Information System (INIS)
Vargas, Maria Carolina; Ramirez, Nubia E.
2002-01-01
Laccase has been obtained through two different production systems, the first using Pleurotus ostreatus in solid-state fermentation, the second one using Trametes versicolor in submerged culture. Different substrates (by products from yeast, flour and beverage industries) have been evaluated in both systems. Maximum laccase yield with Pleurotus ostreatus (25 u/ml) was obtained in a wheat bran medium. The maximum enzyme concentration level using Trametes versicolor (25 u/ml) was achieved in a submerged system, containing 10% vinasse, 4,5% wheat bran and 0,2% molasses per liter of waste. Culture filtrate extracted from Pleurotus ostreatus was used to remove phenol from wastewater. The enzymatic treatment is effective over a wide pH and temperature range. The Laccase treatment has been successfully used to dephenolize industrial petrol refinery wastewater. The advantage of Laccase dephenolization is that this enzyme uses molecular oxygen as an oxidant
-
Energy Technology Data Exchange (ETDEWEB)
Mitchell, J.W.; Watt, J.C.; Cowan, W.F.; Schuyler, S.E.
1983-09-01
Addition of phenol recovery to the wastewater treatment scheme in the Baseline Design for the SRC-I Demonstration Plant was evaluated as a major post-Baseline effort. Phenol recovery affects many downstream processes, but this study was designed to assess primarily its effects on biooxidation and subsequent tertiary treatment. Two parallel treatment schemes were set up, one to treat dephenolated wastewaters and the other for processed nondephenolated wastewaters, a simulation of the Baseline Design. The study focused on comparisons of five areas: effluent quality; system stability; the need for continuous, high-dose powdered activated carbon (PAC) augmentation to the bioreactor; minimum bioreactor hydraulic residence time (HRT); and tertiary treatment requirements. The results show that phenol recovery improves the quality of the bioreactor effluent in terms of residual organics and color. With phenol recovery, PAC augmentation is not required; without phenol recovery, PAC is needed to produce a comparable effluent. Dephenolization also enhances the stability of biooxidation, and reduces the minimum HRT required. With tertiary treatment, both schemes can meet the effluent concentrations published in the SRC-I Final Envivornmental Impact Statement, as well as the anticipated effluent limits. However, phenol recovery does provide a wider safety margin and could eliminate the need for some of the tertiary treatment steps. Based solely on the technical merits observed in this study, phenol recovery is recommended. The final selection should, however, also consider economic tradeoffs and results of other studies such as toxicology testing of the effluents. 34 references, 30 figures and 26 tables.
-
Manufacture of aromatic hydrocarbons from coal hydrogenation products
Energy Technology Data Exchange (ETDEWEB)
A.S. Maloletnev; M.A. Gyul' malieva [Institute for Fossil Fuels, Moscow (Russian Federation)
2007-08-15
The manufacture of aromatic hydrocarbons from coal distillates was experimentally studied. A flow chart for the production of benzene, ethylbenzene, toluene, and xylenes was designed, which comprised the hydrogen treatment of the total wide-cut (or preliminarily dephenolized) fraction with FBP 425{sup o}C; fractional distillation of the hydrotreated products into IBP-60, 60-180, 180-300, and 300-425{sup o}C fractions; the hydro-cracking of middle fractions for increasing the yield of gasoline fractions whenever necessary; the catalytic reform of the fractions with bp up to 180{sup o}C; and the extraction of aromatic hydrocarbons.
-
Directory of Open Access Journals (Sweden)
Xiao-Yan Wang
2012-01-01
Full Text Available Effects of limited hydrolysis with trypsin on the physicochemical and antioxidant properties of buckwheat protein isolates (BPIs obtained with untreated and 2-propanol-extracted meal have been investigated and compared. The dephenolization treatment significantly improved the hydrolysis of BPI, which resulted in the gradual decrease in total and protein-bound polyphenolic content, but an increase in the free polyphenolic content. The hydrolysis of globulins was much easier than that of the albumins. The removal of polyphenols improved the hydrolysis of the albumin fraction. The modified BPIs with high polyphenolic content exhibited much higher DPPH radical scavenging activity and reducing power, but poorer ferrous ion chelating ability than those with low polyphenolic content. These results suggest that the limited hydrolysis is suitable for modification of the properties of buckwheat proteins.
-
Back-echo method for determining the content of C, CH, CH/sub 2/ and CH/sub 3/ fragments
Energy Technology Data Exchange (ETDEWEB)
Polonov, V.M.; Kalabin, G.A.; Kushnarev, D.F.; Latyshev, V.P.
1984-07-01
Possibility was investigated of determining the content of quaternary, tertiary, secondary and primary carbon atoms in soluble products from coal. Cubed residues of medium resin oil from semicoking Cheremkhovskii coals, hydrogenation products from mixtures of medium oil and light dephenolized oil, and asphaltenes separated from the hydrogenation products of Berezovsk coals were used as samples. A new method of quantitative analysis based on the pulse sequence of the back echo from the nuclear magnetic resonance of /sup 13/C was used. The method can be applied in the analysis of light and heavy products from coal, petroleum, shales and complex mixtures of organic substances. The method is limited by a decrease in accuracy when the heteroatom content in the samples increases, causing deterioration in the quality of spectra separation. 13 references.
-
Phenols removal by immobilized tyrosinase reactor in on-line high performance liquid chromatography
International Nuclear Information System (INIS)
Girelli, Anna Maria; Mattei, Enrico; Messina, Antonella
2006-01-01
The development of an immobilized enzyme reactor (IMER) based on tyrosinase immobilized on aminopropyl-controlled pore glass (AP-CPG) for the removal of phenols from model aqueous solutions was reported. To elucidate the influence of the substrate nature, the apparent (V ' max , K ' m ) and the inherent (V max , K m ) Michaelis-Menten constants were determined by Lineweaver-Burk method and the external diffusional contributions on measured enzyme activities were removed by a graphical method. The dephenolization process was realized by recycling the phenol solutions through the bioreactor connected to a chitosan trap in order to remove the colored quinone-type products of the tyrosinase reactions. The results indicated that a complete removal of phenol derivatives in the range of 150-300min, with the exception of 60% removal for phenol reached in 400min, was obtained. The observed sequence: cresol>4-methylcathecol>catechol>4-Cl-phenol-bar phenol was in accordance to the V ' max /K ' m values
-
Energy Technology Data Exchange (ETDEWEB)
1932-12-21
A process is described of desulfurizing, dephenelating, and cracking the dry pitch obtained by dry distillation of lignite, bituminous shale, asphaltic rocks, and peat and fossil coals, that is characterized by the raw material being distilled in a retort together with calcium oxide, the vapors escaping from the still being compelled to pass through a catalyst tube containing calcium oxide mixed with other metallic oxide, the catalyst being helped by suitable heating to a temperature higher than that of the retort mentioned. For the purpose of lessening the quantity of phenolic groups contained in the raw tar to eliminate a great part of the sulfur belonging to the thiophenols and hydrogen sulfide without removing the organic radical to which they are attached, to accomplish a pyrogenic dissociation at the temperature of distillation of the pitch by means of using bone acid (phosphoric) to obtain a greater yield of light hydrocarbon from heavy hydrocarbons. Another purpose is the elimination of sulfur and thiophene and whatever neutral sulfur is contained in the primary pitch, by means of iron sulfate and copper in the anhydrous state or by means of other sulfates whose metals have the ability to form sulfides with sulfur.
-
Phenols removal by immobilized tyrosinase reactor in on-line high performance liquid chromatography
Energy Technology Data Exchange (ETDEWEB)
Girelli, Anna Maria [Dipartimento di Chimica, Universita degli Studi di Roma ' La Sapienza' , P.le Aldo Moro 5, 00185 Rome (Italy)]. E-mail: annamaria.girelli@uniroma1.it; Mattei, Enrico [Dipartimento di Chimica, Universita degli Studi di Roma ' La Sapienza' , P.le Aldo Moro 5, 00185 Rome (Italy); Messina, Antonella [Dipartimento di Chimica, Universita degli Studi di Roma ' La Sapienza' , P.le Aldo Moro 5, 00185 Rome (Italy)
2006-11-24
The development of an immobilized enzyme reactor (IMER) based on tyrosinase immobilized on aminopropyl-controlled pore glass (AP-CPG) for the removal of phenols from model aqueous solutions was reported. To elucidate the influence of the substrate nature, the apparent (V{sup '}{sub max}, K{sup '}{sub m}) and the inherent (V{sub max}, K{sub m}) Michaelis-Menten constants were determined by Lineweaver-Burk method and the external diffusional contributions on measured enzyme activities were removed by a graphical method. The dephenolization process was realized by recycling the phenol solutions through the bioreactor connected to a chitosan trap in order to remove the colored quinone-type products of the tyrosinase reactions. The results indicated that a complete removal of phenol derivatives in the range of 150-300min, with the exception of 60% removal for phenol reached in 400min, was obtained. The observed sequence: cresol>4-methylcathecol>catechol>4-Cl-phenol-bar phenol was in accordance to the V{sup '}{sub max}/K{sup '}{sub m} values.
-
Energy Technology Data Exchange (ETDEWEB)
Paluch, J.; Twardowska, I.
1976-01-01
This article presents a detailed account of the state of water pollution in the main and tributary rivers of the heavily populated and industrialized district of Katowice, Poland: Results of surveys in the years 1969 to 1972 are given. Several tables and maps show the degree of water pollution in rivers, the amount to which the values exceed pollution standards, percentage of treated and untreated industrial waste water entering the rivers, the classification of river sections according to their content of suspensions, phenols and salt. Further figures show the effectiveness of water cleaning flocculating agents and of waste water treatment at coking plants. Black coal mining and processing contributes the greater part to pollution of the rivers. Only 54% of mining industry waste water is cleaned mechanically and 3% chemically. The amount of 3,300 t/d of chlorite and sulfate salts is led into the rivers primarily from the Rybnik coal mining area. The clarification of waste water resulting from hydraulic stowing and from flotation processes is described as most problematic. Research efforts are being made at economic desalination and suspension flocculation. In the coking industry waste water is treated in 88% of the plants, but dephenolization takes place in only 50% of the plants. (29 refs.) (In German)
-
Monti, Matilde; Scoma, Alberto; Martinez, Gonzalo; Bertin, Lorenzo; Fava, Fabio
2015-05-25
Among agro-wastes, olive mill wastewater (OMW) truly qualifies as a high impact organic residue due to its biochemical-rich composition and high annual production. In the present investigation, dephenolized OMW (OMWdeph) was employed as the feedstock for a biotechnological two-stage anaerobic process dedicated to the production of biohydrogen and volatile fatty acids (VFAs), respectively. To this end, two identically configured packed-bed biofilm reactors were operated sequentially. In the first, the hydraulic retention time was set to 1 day, whereas in the second it was equal to 5 days. The rationale was to decouple the hydrolysis of the organic macronutrients held by the OMWdeph, so as to quantitatively generate a biogas enriched in H2 (first stage aim), for the acidogenesis of the residual components left after hydrolysis, to then produce a highly concentrated mixture of VFAs (second stage aim). Results showed that the generation of H2 and VFAs was effectively split, with carbohydrates and lipids, respectively, being the main substrates of the two processes. About 250 ml H2 L(-1) day(-1) was produced, corresponding to a yield of 0.36 mol mol(-1) of consumed carbohydrates (expressed as glucose equivalents). The overall concentration of VFAs in the acidogenic process was 13.80 g COD L(-1), so that 2.76 g COD L(-1) day(-1) was obtained. Second generation biorefineries use a selected fraction of an organic waste to conduct a microbiologically-driven pathway towards the generation of one target molecule. With the proposed approach, a greater value of the waste was attained, since the multi-purpose two-stage process did not entail competition for substrates between the first and the second steps. Copyright © 2014 Elsevier B.V. All rights reserved.