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The biochar is characterized by low surface area and, in order to their use as adsorbent it is possible to use the activation process that allows to liberate and to increase the pores of the surface, increasing its sorption capacity. In the present work the activation of the biochar produced in the pyrolysis of agroindustrial residue (fiber) of the green coconut was studied, being done with sodium carbonate (Na2CO3) at high temperature. Biochar (BC) and activated biochar (ABC) were characterized and ABC was tested for use in the extraction of organic compounds present in the phenolic liquor, produced during the same pyrolysis process. The determination of the textural characteristics was done by N2 adsorption-desorption isotherms, obtaining an area of 1130 m2 g−1 for the ABC, being superior to the area of commercial activated coals, with a total volume of pores of 0.55 cm3 g−1. For the solid phase extraction (SPE) test, 500 mg of ABC were used in cartridges (equal to the commercial ones) obtaining a retention of about 100% of the organic compounds pre-existing in the sample, demonstrating the high adsorptive capacity of the activated biochar produced in this work. Desorption, as expected, had a lower performance than adsorption, being improved using ultrasonic bath, reaching values of the order of 40% recovery.

The characteristics of biodiesel produced can affect its susceptibility to biodegradation by microbial action, which has been of frequent concern since it leads to changes of fuel properties during storage. The goal of the present work was to compare the microbial growth in biodiesel obtained from tallow catalyzed by NaOH or KOH and purified with water or the solid adsorbent magnesium silicate. The experiment was carried out in 200 mL glass bottles containing 45 mL of mineral medium and 5 mL of each type of biodiesel (4 treatments) and 104 spores.mL­–1 of the filamentous fungi Pseudallescheria boydii. The analyses were carried out during 60 days and after each 10 days it was evaluated: fungi biomass formation (dry weight); production of metabolites originated from the fungi growth (pH); variation in the amount of total esters and total glycerol in the oily phase. After 60 days it was possible to observe lower biomass formation in the biodiesel NaOH-water (576 mg) followed by biodiesel NaOH-magnesol (773 mg). The biodiesel KOH-magnesol and KOH-water favored the biomass formation (891 mg and 930 mg respectively)., As características do biodiesel produzido podem afetar a sua suscetibilidade à biodegradação por ação microbiana, o que tem sido uma preocupação freqüente, pois leva a mudanças nas propriedades de combustível durante o armazenamento. O objetivo do presente trabalho foi comparar o crescimento microbiano em biodiesel de sebo bovino, catalisado com NaOH ou KOH e purificado com água ou com o adsorvente sólido silicato de magnésio. O experimento foi realizado em frascos de vidro com capacidade para 200 mL, constituído de 45 mL de meio mínimo mineral e 5 mL de cada tipo de biodiesel (4 tratamentos), e foram adicionados 104 esporos.mL-1 do fungo filamentoso Pseudallescheria boydii. As análises foram realizadas durante 60 dias, a cada 10 dias avaliou-se: formação de biomassa do fungo (peso seco); produção de metabólitos oriundos do crescimento do fungo (pH); e, na fase oleosa, a variação no teor de ésteres totais e de glicerina total. Ao final dos 60 dias, pode-se observar menor formação de biomassa no biodiesel NaOH-Água (576 mg), seguido pelo biodiesel NaOH-Magnesol (773 mg). Os biodieseis KOH-Magnesol e KOH-Água favoreceram a formação de biomassa (891 mg e 930 mg, respectivamente).

Este trabalho tem como objetivo estudar o uso de um resíduo industrial que é a gordura animal para produção de biodiesel metílico usando catálise alcalina. Embora o sebo bovino não seja considerado como fonte renovável de energia, comparado com as oleaginosas, e sim um resíduo industrial, o mesmo desperta grande interesse dos produtores de biodiesel. Além destas vantagens, quando se faz uso de gordura de origem animal tem-se um aspecto ambiental a mais que é o aproveitamento de matérias-primas residuais como biocombustíveis que embora não sejam consideradas fontes renováveis, são resíduos que jogados na natureza se transformam em poluentes de grande demanda de oxigênio. O estudo foi inicialmente feito em laboratório e posteriormente construiu-se uma planta-piloto semi-industrial com capacidade de 800 L dia-1 de biodiesel (com metanol e hidróxido de potássio), sendo o biodiesel aprovado dentro das normas da Resolução 42 da ANP. O biodiesel produzido na planta piloto foi testado em misturas biodiesel/diesel com percentual de 20 %, 30 % e 40 % em motores automotivos Ciclo Diesel (caminhão e automóvel), com resultados plenamente satisfatórios e em todas as estações do ano. Todos os experimentos e testes foram realizados também com óleo de frango, indicando que também esta gordura animal é passível de ser usada na produção de biodiesel, embora com uma conversão um pouco menor. Na terceira etapa deste trabalho elaborou-se uma proposta de planta industrial com capacidade de 20.000 L dia-1, trabalhando com qualquer tipo de gordura, com modificações em vários parâmetros como recuperação de metanol, utilização de centrifuga para acelerar o processo de produção. Também pelos aspectos técnicos o biodiesel produzido atinge aos principais parâmetros de qualidade, com exceção de algumas propriedades, como ponto de entupimento de filtro a frio e viscosidade cinemática, os quais podem ser ajustados através da diluição do biodiesel em diesel petroquímico. The goal of this work is the research in the use of an industrial waste (animal fat) in the biodiesel production with methanol and alkaline catalyst. Although the bovine fat is not considered as renewable source of energy, if compared to oleaginous ones, but an industrial residue, the interest in its use in the of biodiesel has increased in the last years. Besides these advantages, when it is made use of animal fat, an important environmental aspect is the use of a residual raw material as biofuel that, although it is not considered a renewable source, its use plays an important role in the reduction of pollution. The study initially was made in a laboratory scale and after this, it was constructed a semi industrial pilot-plant with a capacity of 800 L day-1 of biodiesel (with methanol and potassium hydroxide), being also obtained a biodiesel that was approved according to the norms of the ANP Resolution 42. The produced biodiesel was tested in blends with 20%, 30% and 40% of biodiesel in mineral diesel were used in automotive motors (truck and car) with highly satisfactory results in any season. Similar tests were made with the chicken oil and these confirm the efficiency of the production process and the quality of the product, in spite the low mass yield. The third step was a theoretical proposal of an industrial plant of biodiesel production with a daily capacity of 20,000 liters, with few modifications in several parameters as the recovery of the excess of methanol and the utilization of a centrifuge in the separation of mixtures and for any kind of fat (also called flex).The results show that is economically feasible the production of biodiesel from animal fats, by using the alkaline methanolic route. Also by the technical aspects, the biodiesel arrives the main quality parameters of the Brazilian specification, except for the plugging point and the kinematic viscosity, which can be adjusted through the dilution in mineral diesel.