ResumoA poluição gerada nos grandes centros urbanos tem origem, principalmente, pela queima de combustíveis fósseis, basicamente gasolina e diesel, que são substâncias de origem mineral formadas pelos compostos de carbono, provenientes da decomposição de materiais orgânicos, a qual perdura milhões de anos. Logo, são considerados recursos naturais não renováveis. A queima destes combustíveis acontece de forma incompleta quando utilizados em máquinas térmicas e veículos automotores, este processo resulta no lançamento de uma grande quantidade de monóxido e dióxido de carbono (gás carbônico) na atmosfera, fazendo destes grandes vilões no que se refere ao aquecimento global e efeito estufa. Vale salientar que estes combustíveis alimentam os setores industrial, elétrico e de transportes de grande parte das economias do mundo. Este trabalho tem como finalidade levantar aspectos ligados à poluição atmosférica decorrente da utilização de veículos automotores.Palavras-chave: poluição atmosférica, combustíveis fósseis, veículos. AbstractThe pollution generated in large urban centers follows mainly from burning fossil fuels, basically gasoline and diesel, which are mineral substances formed by carbon compounds from the decomposition of organic materials, what take millions of years. Therefore, they are considered non-renewable resources. The fuel burning occurs incompletely when employed in heat engines and automotive vehicles, and this process results in release of a large amount of carbon monoxide and carbon dioxide emissions, making these great villains regarding to global warming and the greenhouse effect. It is worth noting that these fuels feed the industrial, electrical and transport of most world economies. This work aims to raise issues related to air pollution from motor vehicles use.

An inactive biomass of a new fungus recently discovered, Diaporthe schini, was evaluated for the biosorption of crystal violet (CV) in simulated textile effluents. The characterization assays were performed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and N2 adsorption/desorption isotherms. The influences of pH and biosorbent dosage on the biosorption capacity were evaluated. Kinetics, equilibrium and thermodynamic studies were also carried out. Characterization techniques showed an amorphous biosorbent, with a rough surface containing irregular particles and surface area of 6.5 m2 g−1. The most adequate values of pH and biosorbent dosage were 7.5 and 0.4 g L−1, respectively. The Elovich kinetic model and the Sips equilibrium model were suitable to fit the experimental data. The biosorption capacity increased with temperature, reaching a maximum biosorption capacity of 642.3 mg g−1 at 328 K. The biosorption was a spontaneous and endothermic process. Diaporthe schini inactive biomass was an interesting biosorbent to treat colored effluents, presenting efficiency of 87% in the decolorization of a simulated dye house effluent.

No abstract

No abstract

Araucaria angustifolia bark (AA-bark), a waste generated in wood processing, was evaluated as a potential adsorbent to remove Gentian Violet (GV) dye from aqueous solutions. The AA-bark presented an amorphous structure with irregular surface and was composed mainly of lignin and holocellulose. These characteristics indicated that the adsorbent contains available sites to accommodate the dye molecules. The GV adsorption on AA-bark was favored at pH 8.0 with adsorbent dosage of 0.80 g L−1. Pseudo-nth order model was adequate to represent the adsorption kinetics of GV on AA-bark. A fast adsorption rate was verified, with the equilibrium being attained within 30 min. Equilibrium data were well represented by the Langmuir model. The maximum adsorption capacity was 305.3 mg g−1. Adsorption was spontaneous, favorable and endothermic. AA-bark was able to treat a simulated dye house effluent, reaching color removal values of 80%. An excellent performance was found in fixed bed experiments, where the length of the mass transfer zone was only 5.38 cm and the breakthrough time was 138.5 h. AA-bark can be regenerated two times using HNO3 0.5 mol L−1. AA-bark can be used as a low-cost material to treat colored effluents in batch and fixed bed adsorption systems.