Toxicological evaluation of vegetable oils and biodiesel in soil during the biodegradation process

Vegetable oils and their derivatives, like biodiesel, are used extensively throughout the world, thus posing an environmental risk when disposed. Toxicity testing using test organisms shows how these residues affect ecosystems. Toxicity tests using earthworms (Eisenia foetida. are widespread because they are a practical resource for analyzing terrestrial organisms. For phytotoxicological analysis, we used seeds of arugula (Eruca sativa and lettuce (Lactuca sativa. to analyze the germination of seeds in contaminated soil samples. The toxicological experiment was conducted with four different periods of biodegradation in soil: zero days, 60 days, 120 days and 180 days. The studied contaminants were soybean oil (new and used) and biodiesel (B100). An evaluation of the germination of both seeds showed an increased toxicity for all contaminants as the biodegradation occurred, biodiesel being the most toxic among the contaminants. on the other hand, for the tests using earthworms, the biodiesel was the only contaminant that proved to be toxic. Therefore, the higher toxicity of the sample containing these hydrocarbons over time can be attributed to the secondary compounds formed by microbial action. Thus, we conclude that the biodegradation in soil of the studied compounds requires longer periods for the sample toxicity to be decreased with the action of microorganisms.

Morphological Changes in Poly(Caprolactone)/Poly(Vinyl Chloride) Blends Caused by Biodegradation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural and morphological changes in Poly(caprolactone)/poly(vinyl chloride) blends caused by UV irradiation

Films made from a blend of poly(epsilon-caprolactone) and poly(vinyl chloride) (PCL/PVC) retained high crystallinity in a segregated PCL phase. Structural and morphological changes produced when the films were exposed to high potency ultraviolet (UV) irradiation for 10 h were measured by UV-Vis spectroscopy (UV-Vis), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM). They were different to those observed with homopolymer PCL and PVC films treated under the same conditions. The FTIR spectra of the PCL/PVC blend suggest that blending decreased the susceptibility of the PCL to crystallize when irradiated. Similarly, although scanning electron micrographs of PCL showed evidence of growth of crystalline domains, particularly after UV irradiation, the images of PCL/PVC were fairly featureless. It is apparent that the degradation behavior is strongly influenced by the interaction of the two polymers in the amorphous phase.

Aerobic biodegradation of butanol and gasoline blends

This work aimed to assess the aerobic biodegradation of butanol/gasoline, blends (5; 10; 15 and 20% v/v), being the latter compared to the ethanol/gasoline blend (20% v/v). Two experimental techniques were employed, namely the respirometric method and the redox indicator DCPIP test. in the former, experiments simulating the contamination of natural environments (addition of 50 mL of fuel kg(-1) of soil from a non-contaminated site and 20 mL of fuel L(-1) of water from a river) were carried out in biometer flasks (250 mL), used to measure the microbial CO(2) production. The DCPIP test assessed the capability of four inocula to biodegrade the blends of 20%. The addition of butanol at different concentrations enhanced the biodegradation of gasoline in soil. However, no practical gains were observed for concentrations of butanol above 10%. Ethanol showed to have a much faster biodegradation rate than butanol, particularly in water, and the following order of biodegradability was found: ethanol > butanol > gasoline. The addition of the alcohols to the gasoline resulted in positive synergic effects on the biodegradation of the fuels in soil and water matrices. Furthermore, results suggest that, in soil, butanol better enhanced the biodegradation of gasoline than ethanol. (C) 2009 Elsevier Ltd. All rights reserved

Synergistic effect in the catalytic activity of lipase Rhizomucor miehei immobilized on zeolites for the production of biodiesel

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Production of biodiesel by esterification of palmitic acid over mesoporous aluminosilicate Al-MCM-41

Biodiesel has been obtained by esterification of palmitic acid with methanol, ethanol and isopropanol in the presence of Al-MCM-41 mesoporous molecular sieves with Si/Al ratios of 8.16 and 32. The catalytic acids were synthesized at room temperature and characterized by atomic absorption spectrometry (AAS), thermal analysis (TG/DTA), X-ray diffraction (XRD), nitrogen absorption (BET/BJH), infrared spectroscopy (IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The reaction was carried out at 130 degrees C whilst stirring at 500 rpm, with an alcohol/acid molar ratio of 60 and 0.6 wt% catalyst for 2 h. The alcohol reactivity follows the order methanol > ethanol > isopropanol. The catalyst Al-MCM-41 with ratio Si/Al = 8 produced the largest conversion values for the alcohols studied. The data followed a rather satisfactory approximation to first-order kinetics. (C) 2008 Elsevier Ltd. All rights reserved.

Determination of phosphorus in biodiesel using 1:12 phosphomolybdic modified electrode by cyclic voltammetry

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Determination of free glycerol in biodiesel at a platinum oxide surface using potential cycling technique

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Voltammetric Determination of Phosphate in Brazilian Biodiesel Using Two Different Electrodes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Determination of potassium ions in biodiesel using a nickel(II) hexacyanoferrate-modified electrode

in this work. nickel hexacyanoferrate-modified electrode was developed to determine potassium ions in biodiesel by potentiometry. The modified electrodes exhibit a linear response to potassium ions in the concentration range of 4.0 x 10(-5) to 1.0 x 10(-2) mol L-1, with a detection limit of 1.9 x 10(-5) mol L-1. and a near-Nernstian slope (53-55 mV per decade) at 25 degrees C. The method developed in this work was compared with flame photometry and the potassium concentration found in biodiesel showed that the modified electrode method gives results similar to those obtained by flame photometry. (C) 2007 Elsevier B.V. All rights reserved.

Strontium zirconate heterogeneous catalyst for biodiesel production: Synthesis, characterization and catalytic activity evaluation

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Biotreatment effects in films and blends of PVC/PCL previously treated with heat

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Metodologia experimental para avaliação de custos de produção e utilização de biodiesel: estudo de caso de quatro ésteres metílicos e óleo diesel comercial

Considerando que o Brasil detém uma vasta gama de matérias-primas para produção de biodiesel, e também que há a possibilidade de produção em pequena escala, prima-se por estudos de cunho econômico a partir de metodologias de fácil execução. O objetivo do trabalho foi demonstrar uma metodologia e sua aplicação para avaliação dos custos inseridos dentro do processo produtivo e de utilização do biodiesel. A metodologia foi aplicada a biodieseis originários de óleo de soja, girassol, frango e sebo bovino, dos quais se avaliaram economicamente os custos fixos e variáveis para conversão química dos óleos e gorduras em ésteres metílicos, em uma planta de produção experimental. Os custos de produção para cada uma das quatro citadas são distintos em função do valor inicial por litro de cada uma. Também fora avaliado o custo específico e o consumo específico de cada um dos biodieseis, a fim de determinar a diferença em relação ao óleo diesel comercial. No estudo de caso, os resultados mostraram vantagens para o óleo diesel, tanto no custo quanto no consumo. Comparando-se os biodieseis, o de sebo bovino apresentou-se com o menor custo de produção e o menor consumo.

Desempenho de um motor de trator agrícola em bancada dinamométrica com biodiesel de óleo de frango e misturas binárias com óleo diesel

O Brasil, terceiro maior produtor de biodiesel do mundo e terceiro maior produtor mundial de frango, pode incrementar, na sua matriz energética, o uso de óleo oriundo de aves como alternativa aos combustíveis fósseis e à redução da dependência do óleo de soja para esse fim. O país dispõe de mais de 350 milhões de litros de óleo de frango por ano. Considerando a aplicação dos combustíveis alternativos para os motores a diesel, em máquinas agrícolas, o trabalho teve por objetivo avaliar o desempenho do motor de um trator agrícola de 53kW acoplado pela TDP em bancada dinamométrica, operando com biodiesel metílico de óleo de frango e misturas com óleo diesel, sendo: B5 (testemunha), B20, B40, B60, B80 e B100. Avaliaram-se a potência, o torque, a reserva de torque, o consumo de combustível, o consumo de energia e a eficiência térmica do motor. O ensaio foi instalado com delineamento inteiramente casualizado (DIC) em esquema fatorial com seis tratamentos. Os resultados foram submetidos à análise de variância e as médias ajustadas por equações de regressão. Foram observadas perdas na geração de potência e torque, aumento no consumo de combustível, redução do consumo energético e melhoria na eficiência térmica do motor, de acordo com o aumento da proporção de biodiesel na mistura.