Treatment influence on green coconut shells for removal of metal ions: pilot-scale fixed-bed column.

This work investigates copper, nickel and zinc ion biosorption in single- and multi-component systems in a fixed-bed column using green coconut shells (CS). Approximately 85% of biosorbents are in a particle size ranging from 0.25 to 2 mm. Operational parameters selected include a flow rate of 200 mL min-1 and a bed height of 100 cm, which were selected for a shorter execution time and good adsorption capacity. Empty-bed contact time and Thomas models were applied, showing a good fit with the experimental data. The column adsorption capacity increased after the green CS powder was treated in a column with NaOH at a concentration of 0.1 mol L-1. The highest values of adsorption capacities founded were 0.69, 0.45 and 0.39 mmol L-1 for Cu(II), Ni(II) and Zn(Il), respectively, using green CS treated inside a column with NaOH of 0.1 M. The pH and chemical oxygen demand were monitored in the treatment solution and indicated that the adjustment of these parameters is necessary before disposal of these solutions. A study of desorption using an acid solution was carried out for recovery of metal ions.

Chemometric characterization of alembic and industrial sugar cane spirits from cape verde and ceará, Brazil.

Sugar cane spirits are some of the most popular alcoholic beverages consumed in Cape Verde. The sugar cane spirit industry in Cape Verde is based mainly on archaic practices that operate without supervision and without efficient control of the production process. The objective of this work was to evaluate samples of industrial and alembic sugar cane spirits from Cape Verde and Ceará, Brazil using principal component analysis. Thirty-two samples of spirits were analyzed, twenty from regions of the islands of Cape Verde and twelve from Ceará, Brazil. Of the samples obtained from Ceará, Brazil seven are alembic and five are industrial spirits. The components analyzed in these studies included the following: volatile organic compounds (n-propanol, isobutanol, isoamylic, higher alcohols, alcoholic grade, acetaldehyde, acetic acid, acetate); copper; and sulfates.