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The present study describes the influence of the concentration of lignin when used as a filler in polyurethane foam for crude oil sorption. The foams (lignin 0-20wt%) were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis, contact angle and density. The FTIR analysis confirmed urethane linkage formation, showing that the chemical structure of the polymer was preserved, despite the addition of different lignin concentrations. Thermogravimetric analysis showed that the presence of lignin has altered the onset temperature (Tonset) of the foams, decreasing as the concentration of lignin is increased. The contact angle analysis showed a decrease in the hydrophobicity of the foams with increasing lignin concentration. All modified foams showed an improvement in the oil sorption capacity in a PUF/oil/water system, and the PUF-10 showed an improvement of about 35.5% compared to the PUF-blank. The Langmuir isotherm showed a better fit to the data and predicted a maximum oil adsorption of 28.9gg-1 by the PUF-10. The ΔG° value of -4.4kJmol-1 indicated that crude oil adsorption process by PUF-10 was spontaneous. The results of reuse of the PUF-10 showed that oil removal efficiency remained greater than 95% after five consecutive cycles.

A chemically modified tung oil was used as the main polyol component in the formulation of viscoelastic (low resilience) polyurethane foams. Rice Husk Ash (RHA), a residue from the rice process industry, was chosen to be incorporated as rigid filler in these materials because of its high silica content. Water was used as blowing agent in order to increase the green nature of the reinforced foams. Physico-chemical and thermal properties of the neat and reinforced foams were measured and analyzed. RHA addition leads to noticeable changes in several properties, mainly thermal conductivity, density and foam morphology, even at the low filler content used in this work. Although the thermal stability was almost unaffected by ash content, a stabilizing effect of the inorganic filler was identified, since the residual char was higher than predicted from theoretical calculations. Fil: Silva, Virginia Ribeiro da. Universidade Federal de Minas Gerais; Brasil Fil: Mosiewicki, Mirna Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Yoshida, Maria Irene. Universidade Federal de Minas Gerais; Brasil Fil: Silva, Mercês Coelho da. Universidade Federal de Minas Gerais; Brasil Fil: Stefani, Pablo Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Marcovich, Norma Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina

In the aluminum industries, there are several steps involved in processing since the extraction of bauxite to obtain the final product (Al). During the development of these, various steps generated wastes. One of them, from the electrostatic filter of the calcination step of the Bayer process is a very fine black powder, rich in alumina (Al2O3) that does not meet industry specifications, and it is discarded in the industry yard. Alumina is a noble material and has high commercial value. This black powder has great prospects for recovery, recycling, and future applications. Therefore, it is important to perform characterization of tailings and to do that we have used XRD, SEM, EDS, FTIR, Raman, and thermal analysis.

Viscoelastic polyurethane (PU) foams based on modified tung oil, ethylene glycol and polymeric MDI, and reinforced with rice husk ash (RHA), were prepared by a free-rise pouring method and characterized in terms of density, compression and dynamic mechanical behavior. The density of foams ranged between 50 and 90 kg/m3, depending on the position of the sample with respect to the foam rise direction and filler content. As revealed by dynamic mechanical tests, the foams exhibited two different and broad thermal transitions, the temperature of their maxima depending on filler concentration. Compression modulus, compressive strength and storage modulus increase as foam density increases but decreases as rice husk ash concentration increases due to the detrimental changes induced by the filler in the foam cellular structure. However, densification strain exhibits the opposite behavior, indicating that reinforced foams can sustain slightly higher deformations without collapsing, probably due to a reduced reactivity of the components induced by the filler. © 2013 Elsevier Ltd. All rights reserved. Fil: Ribeiro Da Silva, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina. Universidade Federal de Minas Gerais; Brasil. Ministry of Education of Brazil. CAPES Foundation; Brasil Fil: Mosiewicki, Mirna Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Yoshida, Maria Irene. Universidade Federal de Minas Gerais; Brasil Fil: Coelho Da Silva, Mercês. Universidade Federal de Itajubá; Brasil Fil: Stefani, Pablo Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Marcovich, Norma Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina

As questões ambientais relacionadas à produção industrial, a busca de produtos renováveis para produção de materiais, tanto conhecidos como inéditos, e o aproveitamento/reciclagem de resíduos têm sido temas de diversos estudos, tanto em ciências como em áreas afins. Neste trabalho, são apresentadas formulações para espumas rígidas de poliuretano (ERPU), partindo-se de reagentes alternativos, de origem não petroquímica. As espumas foram sintetizadas a partir de polióis de óleos vegetais de rícino e tungue, materiais de fonte renovável, que se apresentaram como boa alternativa para a substituição de polióis de origem petroquímica. Às espumas rígidas sintetizadas, foram adicionadas cargas inorgânicas oriundas de rejeitos industriais, com o intuito de se estudar aplicações para estes resíduos e na tentativa de contribuir para a diminuição do impacto ambiental causado por eles. Às espumas produzidas a partir de poliol derivado de óleo de rícino, foi utilizado um pó preto (rejeito P3) que é um rejeito do processo Bayer de produção de alumina. Este rejeito, caracterizado através de diversas técnicas, mostrou-se rico em alumina (Al2O3) e hidróxido de alumínio (Al(OH)3). Devido à alta concentração destas duas substâncias, este material apresenta grande potencial como retardante de chamas para as espumas. Para as espumas produzidas a partir de poliol derivado de óleo de tungue, foi utilizada como carga a cinza de casca de arroz (CCA), rejeito industrial do beneficiamento do arroz, rico em sílica (SiO2) e com potencial de retardância de chamas para as espumas. As espumas obtidas foram caracterizadas por FTIR, análise térmica (TG, DTG e DTA) e MEV. Foram também medidas as densidades dos materiais e realizados ensaios mecânicos, de condutividade térmica e testes de chama, para se avaliar a influência das cargas nas diversas propriedades das espumas. Os resultados encontrados indicam que, para as porcentagens de cargas utilizadas, não há modificações morfológicas significativas nos compósitos, em relação às espumas matrizes. Observou-se um ganho em propriedade de retardância de chamas e não houve perda significativa de propriedades térmicas. Há indicativos de haver interação química secundária do rejeito P3 com o material poliuretânico sintetizado a partir de poliol derivado de óleo de rícino. O mesmo não foi observado para as espumas sintetizadas com poliol derivado de tungue, utilizando-se cinza de casca de arroz como carga inorgânica. Environmental issues related to industrial production, to a search for renewable products for the production of new materials, and recovery / recycling of waste have been subjects of several studies, both in science and in related areas. In this work are presented formulations for rigid polyurethane foams (PURF), using alternative and no petrochemical reactants. The foams were synthesized from vegetables based polyols (castor oil and tung oil based polyols), materials from renewable source, which showed a good alternative for the replacement of petrochemical polyols. Inorganic fillers, derived from industrial waste, have been added to rigid foam, with the intention of study applications for these residues and in an attempt to contribute to reducing the environmental impact caused by them. For the foams produced from polyol derived fromcastor oil, was used a black powder (reject P3) which is a waste from the Bayer process alumina production. This waste was characterized by various techniques and is rich in alumina (Al2O3) and aluminum hydroxide (Al(OH)3). Due to the high concentration of these two substances, this material has great potential as a flame retardant for foam. For the foams produced from tung oil based polyol, was used rice husk ash as the load. This is an industrial waste from the riceprocessing, rich in silica (SiO2), and also with flame retardance potential for the foam. The foams were characterized by FTIR, thermal analysis (TG, DTG and DTA) and SEM. Were also measured densities of materials and are performed mechanical, thermal conductivity and flame tests, to evaluate the load influence in the different foams properties.The results indicate that, for the loads percentages used, there were no morphological changes in the composites, compared to foam matrices. We observed an increment in the property of flame retardance and there was no significant loss of thermal properties. There are indications that there are secondary chemical interactions with the material waste P3 and the polyurethane synthesized castor oil based polyol. The same was not observed for the foams synthesized with tung oil based polyol, where rice husk ash as inorganic filler.

Amostras de polpas de morango industrializadas, comercializadas no estado de Minas Gerais, foram coletadas no período de 2006 a 2007 pelas Vigilâncias Sanitárias e encaminhadas à Fundação Ezequiel Dias para análise de resíduos de agrotóxicos. Realizou-se a extração pelo método de multirresíduos com acetona, diclorometano e hexano. Os extratos obtidos foram submetidos à análise por cromatografia a gás com detectores de captura de elétrons (CG-DCE), fotométrico de chama (CG-DFC) e nitrogênio fósforo (CG-DNF), espectrometria de massa (CG-MS) e cromatografia a líquido de alta eficiência (CLAE) com detectores ultravioleta (UV) visível e fluorescência. Os resultados evidenciaram o uso inadequado de agrotóxicos, sendo detectados produtos não autorizados como acefato, captana, clorfenapir, clorpirifós, dimetoato, ometoato, endossulfam, fenarimol, folpete, metamidofós, procloraz e tetradifona e os autorizados azoxistrobina, difenoconazol, fenpropatrina, iprodiona e procimidona. Isso indica que as boas práticas agrícolas não estão sendo cumpridas por alguns produtores e mostra a necessidade de fiscalização de alimentos processados, o que levaria à oferta de produtos de melhor qualidade.

This work describes the synthesis of composites steatite/flexible polyurethane by replacing 4.5 wt. % of polyol with steatite rock powder. We evaluated two mechanical properties of composites (comfort factor and support factor) for various formulations based on a fractional factorial design. The new synthesized composites showed higher support factor, greater comfort factor, and lower cost, compared to conventional flexible polyurethane foams. There is not a significant change in the chemical composition of the foams, due to substitution of 4.5 wt. % polyol by steatite. However, there was a decrease in cell size and greater interaction between the hard segments of the composite.