Removal of Al (III) and Fe (III) from binary system and industrial effluent using chitosan films.

Adsorption of Al (III) and Fe (III) onto chitosan films from individual and binary systems were investigated. The matrix effect was evaluated using an industrial effluent of the scrubber of gases from the production process of Al2(SO4)3. The adsorption study was carried out by response surface methodology to optimize the adsorption operation as a function of pH (3, 4.5 and 6) and film dosage (FD) (100, 200 and 300 mg L-1).The possible interactions film-ions were investigated by thermal analysis, X-ray diffraction, scanning electron microscopy and dispersive energy X-ray spectroscopy. The more suitable conditions for all experimental designs were the FD values in 100 mg L-1and pH 4.5.The adsorption capacity of Fe (III) in the individual and binary systems were 140.2 mg g-1 and 132.3 mg g-1 respectively; however, in the experiment conducted on the real effluent, the adsorption capacity was reduced to 66.30 mg g-1.Already to Al (III), the adsorption capacities in the individual and binary systems were 665.5 mg g-1 to 621.2 mg g-1 respectively, and when the operation was performed using real effluent the adsorption capacity was reduced to 275.7 mg g-1.

Evaluation of the mineral profile of textile materials using inductively coupled plasma optical emission spectrometry and chemometrics.

The content of Al, Ba, Ca, Cr, Cu, Fe, Ni, P, Zn, Cd and Pb was determined in textile material samples after microwave-assisted decomposition in a cavity oven and extraction with an artificial sweat solution. Radial viewing inductively coupled plasma optical emission spectrometry (ICP OES) was the main detection technique, but Cd and Pb were determined by thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) to increase the sensitivity. Principal components analysis (PCA) was applied to the data sets to characterize the samples with respect to their geographic origin and color difference. The PCA for Brazilian single-color samples showed separation, with one group consisting of blue and green textiles and another with all the other materials evaluated. The geographic origin study showed a clear separation between Brazilian and Chinese textiles. The metals amount extracted with sweat extractable solution were lower than limits values pointed by the International Testing and Certification System for Textiles, Oko Tex Standard 100, in the all considered classes. Recoveries varied from 85 to 112% for additions ranging from 3.0 to 25 mg kg(-1) for Ca and from 0.3 to 7.0 mg kg(-1) for all other analytes through the microwave-assisted decomposition procedure.