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Recebido em 25/05/2017; aceito em 24/10/2017; publicado na web em 04/12/2017 ADSORPTION OF BIODIESEL CONTAMINANTS BY SURFACE-MODIFIED BAGASSE FIBERS. Sugarcane bagasse fibers chemically modified on its surface were used to adsorb contaminants from biodiesel. Two biodiesel samples were used as adsorbates: crude and washed biodiesel. The contaminants were mainly glycerol and water, but also ions, and methanol. The biodiesel is usually washed, in order to remove most of the contaminants, but the procedure introduces large amounts of water, which are further difficult to remove, because the biodiesel acting as an acceptor of hydrogen bond. The adsorbent used in this work was proved to be very efficient to remove the contaminants and also to remove water from the washing the crude biodiesel. The contaminants adsorbed from biodiesel were identified by thermal analyses (DSC and DTA) of the fibers (adsorbent) and of the biodiesel (adsorbate) by comparing the results with the pure biodiesel. The proportion of free glycerol showed high adsorption efficiency for the crude biodiesel. A total amount of 1.34 g of fibers was estimated as being needed for its complete removal. The mass of bagasse fibers added (up to 1g) in a fixed volume of biodiesel was a relevant condition, as the saturation in fibers started at around 0.70 g cleaning up to about 98% removal of the impurities.Keywords: adsorption; bagasse; biodiesel; contaminants. INTRODUÇÃOO suprimento de energia ainda é majoritariamente dependente dos combustíveis fósseis: petróleo, carvão e gás natural. Considerando que as fontes fósseis são finitas, os gases da exaustão, produtos da combustão, são fortemente prejudiciais à sustentabilidade ambiental e os combustíveis têm o preço afetado por conflitos devido a instabilidades políticas, nas áreas de grande produção, são motivos que estimulam mais a ampliação da busca por fontes alternativas de energia e combustíveis renováveis. No cenário de inovação do mercado energético mundial, o Brasil tem destaque devido ao seu potencial de produção de biocombustíveis, tanto para suprir sua demanda interna quanto para exportar. 1 A grande extensão territorial do Brasil (é o quinto país de maior extensão de área territorial do globo) e a sua localização geoclimá-tica, situado em sua maior parte na zona tropical, favorece produção de biomassas diversificadas, sendo praticamente toda sua extensão aproveitável para a exploração agropecuária.2 Assim sendo, é viável a destinação de espaços para a cultura de vegetais oleaginosos, visando à produção de biocombustíveis.Biocombustíveis são substâncias derivadas de biomassa em base renovável, podendo substituir parcial ou totalmente os combustíveis fósseis. São empregados diretamente ou com poucas alterações, em motores a combustão interna ou, também, para outros tipos de geração de energia. Assim como o etanol, o biodiesel tem significativas vantagens ambientais. Estudos do National Biodiesel Board 7 (associação que representa a indústria de biodiesel nos Estados Unidos) demonstraram que a queim...

Abstract. Biodiesel wastewater generally contains high levels of oils, soaps and glycerol residues. This needs wastewater treatment. In this study, the biodiesel wastewater treatment was tested (industrial wastewater (EFID) and laboratory wastewater (EFLB) from biodiesel) by performing flocculation and dual-flocculation with renewable polymers. Tannin and cationic hemicellulose (CH) were used as cationic flocculant, and cellulose acetate sulfate (CAS) was used as an anionic flocculant. Polyacrylamide (PAM) was used as a reference anionic flocculant for result efficiencies analysis obtained with CAS (renewable source flocculant). The treatment efficacy in wastewater was evaluated by: turbidity removal, sludge volume formed, chemical oxygen demand (COD) and total suspended solids (TSS). The obtained sludge was studied using thermogravimetric analysis (TG). The dual-flocculation application condition of the 25% proportion of tannin (T) and 75% proportion of cationic hemicelluloses (i.e., T25/CH75) showed EFLB turbidity removal of 89.1% and 89.5% for CAS and PAM additions respectively, and for EFID of 67% and 41% for CAS and PAM additions respectively. The dual-flocculation performance suggested that the polyelectrolytes obtained from renewable sources can be used for treating biodiesel wastewater.

em biocombustíveis, número 0 3 /ppbic. Data: 17/03/zui/ " ,. , nrD(vn Discente: Elaine Angélica Mundim Ribeiro _ M atrícula: 13313PGB002 TItulo do Trabalho: Lignocelulósicos nos processos de purificação de biodiese por via umi a utilizando floculantes de fontes renováveis e processo de separação com membranas de celulose regenerada. Área de Concentração: Biocombustíveis Linha de Pesquisa: Produtos e Coprodutos Projeto de Pesquisa de V inculação: Agregação de valor a resíduos da biomassa vegetal, bagaço e cana-de-açúcar, paiha de milho e vagem de amendoim. Às quatorze horas do dia dezessete de março do ano dois mil e dezessete, no Auditório M anuel Gonzalo Hernández-Terrones, do Bloco 51

Hemicelluloses were extracted from corn husk and converted into cationic hemicelluloses using 2,3-epoxypropyltrimethylammonium chloride. The degree of substitution was determined as 0.43 from results of elemental analysis. The cationic derivative was also characterized by Fourier transform infrared spectroscopy and Carbon-13 magnetic nuclear ressonance. The produced polymer was employed as coagulant aid in a sewage treatment station (STS) of the municipal department of water and sewer (Departamento Municipal de Água e Esgoto -DMAE) in Uberlândia-Minas Gerais, Brazil, using Jar test experiments. Its performance was compared to ACRIPOL C10  , a commercial cationic polyacrylamide regularly used as a coagulant at the STS. The best result of the jar-test essays was obtained when using cationic hemicelluloses (10 mg L -1 ) as coagulant aid and ferric chloride as coagulante (200 mg L -1 ). The resultsof color and turbidity reduction, 37 and 39%, respectively, were better than when using only ferric chloride. These results were also higher than those of commercial polyacrylamide, on the order of 32.4 and 38.7%, respectively. The results showed that the cationic hemicelluloses presented similar or even superior performance when compared to ACRIPOL C10  , demonstrating that the polyelectrolytes produced from recycled corn husks can replace commercial polymers in sewage treatment stations.

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