Synthesis of biodiesel from waste cooking oil using immobilized lipase in fixed bed reactor

Waste cooking oil (WCO) is the residue from the kitchen, restaurants, food factories and even human and animal waste which not only harm people's health but also causes environmental pollution. The production of biodiesel from waste cooking oil to partially substitute petroleum diesel is one of the measures for solving the twin problems of environment pollution and energy shortage. In this project, synthesis of biodiesel was catalyzed by immobilized Candida lipase in a three-step fixed bed reactor. The reaction solution was a mixture of WCO, water, methanol and solvent (hexane). The main product was biodiesel consisted of fatty acid methyl ester (FAME), of which methyl oleate was the main component. Effects of lipase, solvent, water, and temperature and flow of the reaction mixture on the synthesis of biodiesel were analyzed. The results indicate that a 91.08% of FAME can be achieved in the end product under optimal conditions. Most of the chemical and physical characters of the biodiesel were superior to the standards for 0(#)diesel (GB/T 19147) and biodiesel (DIN V51606 and ASTM D-6751).

Lipase-catalyzed synthesis of biodiesel from acid oil in fixed bed reactor

Acid oil, which is a by-product in vegetable oil refining, mainly contains free fatty acids (FFAs) and acylglycerols and is a feedstock for production of biodiesel fuel now. The transesterification of acid oil and methanol to biodiesel was catalyzed by immobilized Candida lipase in fixed bed reactors. The reactant solution was a mixture of acid oil, water, methanol and solvent (hexane) and the main product was biodiesel composed of fatty acid methyl ester (FAME) of which the main component was methyl oleate. The effects of lipase content, solvent content, water content temperature and flow velocity of the reactant on the reaction were analyzed. The experimental results indicate that a maximum FAME content of 90.18% can be obtained in the end product under optimum conditions. Most of the chemical and physical properties of the biodiesel were superior to the standards for 0(#) diesel (GB/T 19147) and biodiesel (DIN V51606 and ASTM D6751).

Conversion of Soybean oil to Biodiesel Fuel with Immobilized Candida Lipase on Textile Cloth

The characteristic of biodiesel fuel production from transesterification of soybean oil is studied. The reactant solution is the mixture of soybean oil, methanol, and solvent. A new lipase immobilization method, textile cloth immobilization, was developed in this study. Immobilized Candida lipase sp. 99-125 was applied as the enzyme catalyst. The effect of flow rate of reaction liquid, solvents, reaction time, and water content on the biodiesel yield is investigated. Products analysis shows that the main components in biodiesel are methyl sterate, methyl hexadecanoate, methyl oleate, methyl linoleate, and methyl linolenate. The test results indicate that the maximum yield of biodiesel of 92% was obtained at the conditions of hexane being the solvent, water content being 20 wt%, and reaction time being 24 h.

Lipase-catalyzed regioselective acylation of diosgenyl saponins

Diosgenyl saponins were regio selectively acylated by Novozyme 435 with vinyl esters as acylating agents in THF to afford the corresponding mono- or diacyl diosgenyl saponins. (C) 2001 Elsevier Science Ltd. All rights reserved.

La pensée Sensible

Tese apresentada à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Doutor em Ciências Sociais, especialidade em Psicologia

Geometrías: fundamentación y experiencia sensible

Los profesores de matemáticas asociamos la discusión acerca de la fundamentación y axiomatización de las matemáticas con complejos teoremas y representaciones (Gódel, Cohen, Axiomática de GodelBernays, por ejemplo), bastante apartados de la matemática educativa. Pero su conocimiento, aún a nivel general, es interesante por sí mismo y clave para la observación de las matemáticas como una disciplina en constante transformación, más real que la visión habitual de un cuerpo estático e indiscutible de conocimientos. Por ello, me pareció conveniente, mostrar a los alumnos, una parte de la historia de los fundamentos de la geometría y su peculiar relación con el ser humano que es quien la crea o, por lo menos, la descubre, debate y aplica.

ALCOHOL-RELATED KNOWLEDGE AND ATTITUDES IN PEOPLE WITH A MILD LEARNING-DISABILITY - THE EFFECTS OF A SENSIBLE DRINKING GROUP

Alcohol-related knowledge and attitudes in people with a mild learning disability, who were either living, or being prepared to live, in relatively independent conditions in the community, were assessed through a structured interview format. Compared with non-learning-disabled teenagers, adults and a hospitalized patient sample, alcohol-related knowledge in the people with a learning disability was found to be significantly poorer, alcohol was reported as having particularly negative effects and susceptibility to social pressure to drink alcohol was greater. A 'sensible drinking' group, taking a social skills and influences approach to alcohol education, was conducted with a subgroup of the individuals with a learning disability. The group format and methods, including in vivo sessions in a public house, are described. Follow-up evaluations suggested some significant positive changes in knowledge, attitudes and sensible drinking skills. It is concluded that this population, which is increasingly living, or being moved into, independent conditions in the community, is at least as vulnerable to social influences on alcohol use and abuse as are young people. As with young people, the usefulness of making available such alcohol-education programmes as described in this study, is discussed.

Production of lipase by extractive fermentation with ionic liquids

Novos processos fermentativos, designados por processos de Fermentação Extractiva, são caracterizados por apresentarem etapas de produção e extracção em simultâneo. A extracção líquido-líquido como técnica de separação é amplamente usado na indústria química pela sua simplicidade, baixo custo e facilidade de extrapolação de escala. No entanto o uso de solventes orgânicos nestes processos potencia os riscos ocupacionais e ambientais. Neste contexto, o uso de sistemas de duas fases aquosas baseados em líquidos iónicos, apresenta-se como uma técnica eficaz para a separação e purificação de produtos biológicos. Este trabalho apresenta um estudo integrado sobre o uso de líquidos iónicos não aromáticos foram determinados. A capacidade para a formação de sistemas de duas fases foi estudada para uma vasta gama de líquidos iónicos hidrofílicos com diferentes aniões, catiões e cadeias alqúilicas. A capacidade de separação e purificação de um largo conjunto de líquidos iónicos foi posteriormente investigada, recorrendo-se ao uso de várias biomoléculas modelo de diferentes graus de complexidade, um amino-acido (L-triptofano) e duas enzimas lipolíticas (enzima produzida pela bactéria Bacillus sp. e Candida antarctica lipase B – CaLB). Esta última foi ainda usada para um estudo de biocompatibilidade, tendo sido determinado o efeito de diferentes LIs hidrofílicos na sua actividade enzimática. Este trabalho mostra um estudo ecotoxicológico duma vasta gama de líquidos iónicos e espécies aquáticas, inseridas em diversos níveis tróficos. A bioacumulação foi investigada através do estudo dos coeficientes de distribuição 1-octanol-água (Dow).

The Artpolitics of May Stevens’ work: disrupting the distribution of the sensible

In this paper I look into the life and art of May Stevens, an American working class artist, feminist and committed political activist. I am particularly interested in how Stevens' artwork is inextricably interwoven with her politics, constituting, as I will argue, an assemblage of artpolitics. The discussion draws on Jacques Rancière's analyses of the politics of aesthetics and particularly his notion of ‘the distribution of the sensible’. What I argue is that although Rancière's approach to the politics of aesthetics illuminates an understanding and appreciation of Stevens' art, his idea about the redistribution of the sensible is problematic. It is here that the notion of artpolitics as an assemblage opens up possibilities for a critical project that goes beyond the limitations of Rancière's proposition.