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Recebido em 14/1/09; aceito em 8/7/09; publicado na web em 11/1/10 REMOVAL OF COPPER(II) FROM SUGAR-CANE SPIRITS EMPLOYING CHITOSAN. A method employing chitosan as complexant agent in the removal of copper(II) ions generally present in the Brazilian cachaça samples is herein proposed. The efficiency of this method is attributed to its high capacity of metal cations adsorption, mainly due to presence of hydroxyl and amine groups that can serve as chelating sites. The removal of copper(II) ions from this alcoholic beverage was efficient employing either in column and batch system. The analysis were carried out employing the flame atomic absorption spectrometry and the remaining copper(II) concentrations in the treated cachaça were lower than LOD of FAAS technique.

A flow injection piezoelectric procedure is proposed for the determination of brix (total solids dissolved) in the alcoholic fermentation process. A piezoelectric Perspex cell was constructed to fit one of the gold electrodes of a 10 MHz crystal and this sensor was adapted to a flow injection system. The analytxal curve is linear over the brix range from 0.5 to 20.0% with a detection limit of 0.3 %.Seventy results can be obtained per hour and the relative standard deviation was less 2411 2412 MAGNA, DE OLIVEIRA, AND FATIBELLO-FILHO than 1.45% for a solution containing 6% of brix (n=15). Applications of this method for the determination of brix in sugar cane juice and in an alcoholic fermentation bench show satisfactory results in comparison with refractometric and densimetric methods, respectively.

Recebido em 30/11/06; aceito em 13/7/07; publicado na web em 19/12/07 POTENTIOMETRIC TITRATIONS OF METAL CATIONS WITH EDTA USING THE Cu/Cu(II)-EDTA SYSTEM AS INDICATOR ELECTRODE. In potentiometric titrations of metal cations with EDTA the Hg/HgY 2-system is usually used to detect the end point. However, the use of mercury has been discouraged in analytical procedures due to its toxicity. In this work the Cu/CuY 2-system was used as indicator electrode for potentiometric titrations of some metal cations with EDTA.