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Screening of lipase carriers for reactions in water, biphasic and pure organic solvent systems

100%
Hrydziuszko Z., Dmytryk A., Majewska P., Szymańska K., Liesiene J., Jarzębski A., Bryjak J.
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2014
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vol. 61
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issue 1
1-6
EN
In bioprocesses lipases are typically used in immobilized form, irrespective of type of reaction systems, to ensure an even distribution of catalysts in water restricted media and/or to facilitate separation and reuse. In these studies we report on the selection of appropriate enzyme-carrier preparation for hydrolysis reaction in aqueous and biphasic systems and transesterification in organic solvent. For this Candida rugosa lipase was bound by adsorption or covalent attachment onto various carriers to give 24 preparations. Selection of proper preparation was based on reactivity, thermal stability (4 h at 60°C), possibility of drying and operational stability in 17-23 successive batch processes of 4-nitrophenyl palmitate hydrolysis in water. Activity of preparations varied from 20 to 5100 U∙mL-1 but the most stable preparations were those of moderate activity: bound by adsorption or covalent attachment to NH2-Kieselgel or acrylic carrier (retained activity over 90%). Selected preparations were used for hydrolysis of ethyl (1-butyryloxyethyl)-phenylphosphinate in biphasic system, and, after drying, in ethyl (1-hydroxyethyl)-phenyl-phosphinate transesterification. In this study operational stability was the principal criterion of selection. In water system, lipase covalently bound to NH2-Kieselgel was the best - preserved 50% of initial activity in consecutive batch processes. In biphasic system and lipase covalently bound to acrylic and NH2-Kieselgel the values were 90 or 77%, respectively, whereas in organic solvent, when lipase was immobilized on NH2-Kieselgel by adsorption, it was 50%. Thus, NH2-Kieselgel appears to be an universal matrix for investigated lipase immobilization and can be used in all reaction systems.
2
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Niobia supported on silica as a catalyst for Biodiesel production from waste oil

100%
Tesser R., Vitiello R., Carotenuto G., Garcia Sancho C., Vergara A., Maireles Torres P. J., Li C., Di Serio M.
Catalysis for Sustainable Energy
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2014
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vol. 1
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issue 1
EN
The activity and stability of niobia supported on silica catalyst have been tested in continuous micro-pilot reactors, for biodiesel production starting from acid vegetable oils. A catalyst was prepared by the impregnation of silica pellets with a loading of 12% of Nb and was extensively characterized. The activity of this catalyst in both esterification and transesterification was tested in a continuous micro-pilot laboratory plant in which acid oil was fed (FFA 10% w/w) at a temperature of 220°C and at a pressure of 60 bar. The niobia based catalyst resulted in a very active catalyst in both esterification (FFA conversion = 95-90%) and transesterification reactions (FAME yield = 80-90%), and the activity remained quite constant for more than 100 h on stream. Notwithstanding this stability, a non-negligible leaching phenomena has been detected, in the case of long-time continuous runs, as the Nb concentration on the spent catalyst resulted lower than that on the fresh one. The obtained result confirms that the leaching of the active specie is one of the most strong problem in heterogeneous catalysis for biodiesel production.
3
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Biorefineries - from biofuels to the chemicalization of agricultural products

88%
Kijeński J.
Polish Journal of Chemical Technology
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2007
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vol. 9
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issue 3
42-45
EN
The recent research into the viable economy in sustainable energy from renewable sources has prompted a review into the potentials of Polish-oriented raw material sources as a catalyst for technological advance, product diversification and consumer satisfaction. The elongation of the process chain in vegetable (rape seed, potato), alcohol additives and glycerin processing has been found to drastically improve energy balances for the short processing methods adopted presently and can make Poland self sustainable in the future.
4
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Kinetics of Enantiomerically Enriched Synthesis of Solketal Esters Using Native and SBA-15 supported P. Fluorescens Lipase

88%
Zniszczoł A., Szymańska K., Kocurek J., Bryjak J., Walczak K., Jarzębski A.
Chemical and Process Engineering
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2017
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vol. 38
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issue 2
5
Content available remote

Simulation and sensitivity analysis for biodiesel production in a reactive distillation column

75%
Agarwal M., Singh K., Chaurasia S. P.
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EN
The conventional process for biodiesel production by transesterification is still expensive due to a need of high excess of alcohol required and its recovery by distillation. The use of a reactive distillation process can reduce the amount of alcohol in the feed stream as it works on a simultaneous reaction and separation. In the present study, a mathematical model has been developed for biodiesel production from triglycerides in a reactive distillation column, which has been validated with the reported data and CHEMCAD results. The effects of process parameters such as methanol to oil feed ratio, feed temperature, and reaction time have been investigated. The sensitivity analysis shows that yield of ester increases with methanol to oil ratio and number of stages, however, it decreases with fl ow rate. The MATLAB simulated results show that methanol to oil molar ratio of 5:1 produces 90% (by wt.) of methyl ester in a residence time of 4.7 minutes.
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