Um novo método para quantificação de glicerol em aguardentes de cana de açúcar (cachaças) foi proposto baseado na derivatização das amostras com cloreto de benzoíla seguido por extração em fase sólida e análise via cromatografia líquida de alta eficiência com detector de arranjo de diodos. Os limites de detecção e de quantificação para a análise de glicerol são de 0,25 e 0,74 mg L−1, respectivamente. A exatidão é de 97,5%, a precisão de 93,5% e a linearidade r2 = 0,998 para o intervalo de 0,56 mg L−1 a 112,0 mg L−1 de glicerol. Experimentos com quarenta e oito amostras de cachaças envelhecidas e não envelhecidas e sete extratos etanólicos de madeira mostraram que o processo de envelhecimento contribui para o aumento da concentração de glicerol. A concentração média de glicerol nas amostras de cachaças envelhecidas foi cerca de 10 vezes maior em relação às das cachaças não envelhecidas.

A new method for glycerol quantification in sugarcane spirits (cachaças) is proposed, based on sample derivatization using benzoyl chloride followed by solid-phase extraction and high performance liquid chromatography with diode array detection analysis. The limits of detection and quantification for glycerol analysis are 0.25 mg L−1 and 0.74 mg L−1, respectively. The accuracy is of 97.5%, the precision 93.5% and the linearity r2 = 0.998 in the range of 0.56 mg L−1 to 112.0 mg L−1 of glycerol. Experiments with forty eight samples of aged and non-aged cachaças and seven alcoholic extracts of wood showed that the aging process contributes to increase the glycerol concentration. The average concentration of glycerol in aged cachaças were about 10-fold higher than in non-aged cachaças.

The present study deals with phenol adsorption on chitin and chitosan and removal of contaminants from wastewater of a petroleum refinery. The adsorption kinetic data were best fitted to first- and second-order models for chitosan and chitin, respectively. The results of adsorption isotherms showed Langmuir model more appropriately described than a Freundlich model for both adsorbents. The adsorption capacity was 1.96 and 1.26 mg/g for chitin and chitosan, respectively. Maximum removal of phenol was about 70-80% (flow rate: 1.5 mL/min, bed height: 18.5 cm, and 30 mg/L of phenol. Wastewater treatment with chitin in a fixed-bed system showed reductions of about 52 and 92% for COD and oil and greases, and for chitosan 65 and 67%, respectively. The results show improvement of the effluent quality after treatment with chitin and chitosan.