Determinação de contaminantes em óleos lubrificantes usados e em esgotos contaminados por esses lubrificantes

A simple and reliable ashing procedure is proposed for the preparation of used lubricating oil samples for the determination of Zn, Fe, Pb, Ni and Cu by the flame atomic absorption spectrometry technique. Sulphanilic acid was added to oil samples, the mixture coked and the coke ashed at 550 ºC. The solutions of the ash were analysed by flame AAS for these metals. The quantification limits were 38.250 µg g-1 for Zn, 4.550 µg g-1 for Fe, 1.562 µg g-1 for Pb, 1.450 µg g-1 for Ni, and 0.439 µg g-1 for Cu. The determinations, in lubricating oil, showed good precision and accuracy with recoveries between 90 and 110 %, indicating a negligible matrix effect in the experiments using addition of analyte, with relative standard deviation lower than 5%. The results for analysis of wastewater contamined by theses lubricants showed a very high relative standard deviation.

Modificação química e física do amido de quirera de arroz para aproveitamento na indústria de alimentos

The study evaluated the efficiency of chemical (phosphorylation) and physical (extrusion) modifications of the starch of broken rice. Results demonstrated a reduction in the moisture content of extruded and phosphorylated broken rice and an increase in the ash content of phosphorylated broken rice. Both phosphorylation and extrusion increased cold water binding capacity, swelling power, and solubility. Extruded and phosphorylated pastes were stable under refrigeration, but only extruded paste was stable when submitted to freezing. Phosphorylated paste had the lowest viscosity and the highest stability during heating, while the extruded one gelatinized without heating, but had higher losses during heating.

Aproveitamento sustentável de biomassa e de recursos naturais na inovação química

Increased production of biomass is currently the only immediately accessible alternative for large-scale carbon sequestration and it can produce large amounts of food, fuel and raw materials for the chemical industry that can in turn growingly replace oil as a source of organic building blocks and also of hydrogen and sulfur. Development of processes for biomass and abundant minerals transformation into chemical raw materials should now benefit from large inputs from nanotechnologies, biotechnologies, information and micro-reactor technologies. Success in R&D&Innovation along this line can yield new products and processes needed to perform desirable functions within a sustainable development paradigm.

Alternativa potencial para aproveitamento do glicerol gerado na produção de biodiesel: síntese enzimática de monolaurina por esterificação

Esterification reactions of glycerol with lauric acid in solvent free system were carried out using lipases from several sources. All lipases were immobilized on polysiloxane-polyvinyl alcohol particles by covalent binding with high activity recovered. Among the tested enzymes, the Candida antarctica lipase allowed to attain the highest molar conversion (76%), giving similar proportions of monolaurin, dilaurin and low amount of trilaurin. To further improve the process, the Response Surface Methodology (RSM) was used and optima temperature and molar ratio glycerol to lauric acid were found to be 45 ºC and 5:1, respectively. Under these conditions, 31.35% of monolaurin concentrations were attained and this result was in close agreement with the statistical model prediction.

Determinação de Cd e Pb: avaliação de sedimentos do Rio Jundiaí - SP e Ribeirão Piraí - SP e lodo proveniente de uma estação de tratamento de esgotos

Jundiaí river is the main stream in the Jundiaí Hydrographic Basin and its water is not considered safe for public supply. The water problem is getting worse with the development of the region. The Pirai stream, have been one of the last potable water resource. With the purpose of investigating the sediment quality, due to its influence on the water quality, bioavailable and total Cd and Pb were determined using TS-FF-AAS. Total Cd and Pb up to 2.47 and 24.7 µg g-1 were measured, respectively. The wastewater sludge showed concentrations of 4.01 and 171 µg g-1, for the same metals.

Caracterização de contaminantes presentes em sistemas de tratamento de esgotos, por cromatografia líquida acoplada à espectrometria de massas tandem em alta resolução

This work shows results on the characterization, by liquid chromatography coupled to high resolution tandem mass spectrometry (LC-IT-TOF-MS) with electrospray ionization, of organic compounds present in raw and treated effluents from a combined sewage treatment systems (upflow anaerobic sludge blanket-trickling filter). The sewage samples were prepared by C18 solid phase extraction and the spectra obtained from the various extracts were submitted to principal component analysis to evaluate their pattern and identify the major deprotonated species. Some target compounds were submitted to semiquantitative analysis, using phenolphtalein as internal standard. The results showed the anaerobic step had little impact on the removal of anionic surfactants (LAS), fatty acids, and some contaminantes such as bisphenol A and bezafibrate, whereas the aerobic post-treatment was very efficient in removing these organics.

Esterois como indicadores do acúmulo de esgotos domésticos em sedimentos de um sistema estuarino-lagunar tropical (Mundaú-Manguaba, AL)

The history of sewage contamination in the Mundaú-Manguaba estuarine lagoon system (NE Brazilian coastal zone) was evaluated through the concentration of sterols in sediment cores. The concentration of coprostanol increased towards the surface sediments, with the maximum of 5.65 µg g-1 at 0-2 cm sediment layer in Mundaú. Manguaba exhibited a lower level of contamination. The ratio cholestanol/cholesterol suggested degradation of coprostanol only before the burial of organic matter in the sediment. This feature, together with information of population growth in the watershed, allowed the estimation of a sedimentation rate of 0.90 cm year-1 to the Mundaú lagoon.

Desenvolvimento de metodologia para avaliar remoção de estrogênios em estações de tratamento de esgotos

The present research aimed to study the parameters that affect the determination of estrogens in sewage upon the use of SPE and determination by using gas chromatography mass spectrometry (GC/MS). The study evaluated the stabilization pond technology with regard to estrogens removal. The results showed that the methodology was able to identify and quantify the estrogens E1, E2, E2-17A and EE2 in sewage. Moreover, the estrogens sometimes were not removed in the stabilization pond, showing that even the high hydraulic retention time (HRT) and high sunlight intensity were not enough to degrade these compounds completely during load peaks.

Aproveitamento da glicerina proveniente da produção de biodiesel na obtenção de híbrido de caulinita para adsorção de Cr3+

The aim of this work was to contribute to the creation of new ways of treating wastewater contaminated with Cr3+, based on solid-liquid adsorption. An adsorbent material was prepared by functionalization of kaolinite with glycerin biodiesel by-product. This material was tested for adsorption performed using a batch method, and results showed that inclusion of glycerin in the structure of kaolinite led to a significant increase in the capacity of Cr3+ adsorption. This contributes to the allocation of by-product of biodiesel and to the treatment of effluents from tanneries.

Emissões de óxido nitroso do tanque de aeração de uma estação de tratamento de esgotos com sistema de lodos ativados convencional

Nitrous oxide (N2O) emissions were measured monthly from January to June 2010 in the aeration tank of a wastewater treatment plant (WWTP) in Southeast Brazil. Emissions were lower in summer than winter and were positively related with influent ammonium (NH4+) concentration. The average N2O emission was 1.11 kg N day-1 corresponding to 0.02% of the influent total nitrogen load. The average emission factor calculated for the population served was 2.5 lower than that proposed by the Intergovernmental Panel on Climate Change (IPCC) for inventories of N2O emissions from WWTPs with controlled nitrification and denitrification processes.

Caracterização de membranas assimétricas de acetato de celulose produzidas a partir do aproveitamento do resíduo da palha de milho para uso em ultrafiltração

Cellulose acetates (CA) with different degrees of acetylation were synthesized from cellulose extracted from corn stover. Membranes were prepared for the ultrafiltration process with pure polymers and blend form of CA utilizing a dioxane/acetone system. The membranes were characterized according to their transport properties. The blend form materials presented the best results for application in ultrafiltration experiments. M-TAC/DAC (corn stover triacetate and diacetate) and M-TAC/DAC-Rho (corn stover triacetate and Rhodia diacetate) presented rejection to egg albumin protein of 87.39% and 80.50%, respectively. Thus, MWCO of 45 kDa was determined for these materials.

APROVEITAMENTO DE RESÍDUO DE BIODIESEL PARA PREPARAÇÃO DE CARVÕES ÁCIDOS COM ELEVADA ATIVIDADE CATALÍTICA NA REAÇÃO DE ETERIFICAÇÃO DO GLICEROL

Environmentally friendly acid carbon (CG) catalysts, containing a high amount of sulfonated and oxygenated groups, were prepared from glycerin, a biodiesel waste. CGs were produced by glycerin carbonization in the presence of H2SO4 at 1:3 m:m ratio in a closed autoclave at 180ºC for different times: 0.25; 1; 3 and 6 hours (CG-0.25h; CG-1h; CG-3h and CG-6h, respectively). The catalyst properties for all carbons were evaluated in the glycerol etherification reaction with tert-butyl alcohol (TBA). The yield for mono-tert-butyl glycerol (MTBG), di-tert-butyl glycerol (DTBG) and tri-tert-butyl-glycerol (TTBG) was high and very similar for all CGs, of about 43% and 20% for the MTBG and DTBG + TTBG, respectively. Furthermore, the activity of these catalysts were close to those obtained using a commercial resin, Amberlyst-15, of about 50% and 27% for MTBG and DTBG + TTBG, respectively.

Aproveitamento teórico-prático da disciplina anatomia humana do curso de fisioterapia

A Anatomia Humana estuda as estruturas do corpo humano e as relações entre elas. Assim, seu ensino a estudantes da área da saúde, incluindo alunos de Fisioterapia, é de extrema importância. É necessário um bom aproveitamento nesta disciplina para se tornar um bom profissional, porém as estratégias de ensino-aprendizagem nesta disciplina têm sido bastante discutidas. Com base nesta premissa, este estudo teve por objetivos avaliar o aproveitamento teórico-prático dos discentes do curso de Fisioterapia na disciplina Anatomia Humana, bem como descrever as facilidades e dificuldades enfrentadas e suas implicações durante o curso. Para tanto, foi elaborado um questionário específico e utilizada também a avaliação dos professores realizada pelo Colegiado de Fisioterapia. O tratamento estatístico foi composto por análise descritiva e correlação de Pearson, sendo os dados analisados pelos programas Microsoft Excel® 2007 e Graphpad Prism®. Não se observou correlação entre desempenho do aluno e grau de satisfação diante de diferentes parâmetros analisados neste trabalho. O estudo revelou que os alunos apresentam aproveitamento satisfatório, mas há grandes insatisfações quanto à forma como a disciplina é conduzida.

Utilização de águas residuárias provenientes do tratamento biológico de esgotos domésticos na produção de mudas de Eucalyptus grandis Hill. ex. maiden

Este trabalho teve por objetivo estudar a viabilidade do uso de águas residuárias provenientes de um sistema biológico de tratamento de esgotos domésticos como alternativa à fertirrigação convencional de viveiros florestais, visando à produção de mudas de Eucalyptus grandis via subirrigação contínua. As variáveis avaliadas foram: altura, diâmetro do coleto, peso da matéria seca da parte aérea e da raiz, área foliar, razão raiz/parte aérea e concentração nutricional foliar. O desenvolvimento das plantas, em geral, foi superior no tratamento convencional com adubos minerais. A razão raiz/parte aérea foi favorecida no tratamento com água residuária. Os resultados indicaram que a água residuária pode ser utilizada na fertirrigação de viveiros para a produção do Eucalyptus grandis, pois todas as plantas cresceram, sem deficiência ou toxidez aparente. Entretanto, constatou-se que essas mudas necessitavam de um maior tempo no viveiro, em comparação com as produzidas com fertilizantes minerais.