Adsorptive removal of arsenic from river waters using pisolite

This work presents the experimental results for arsenic removal from aqueous solutions using pisolite as a natural inorganic sorbent, a waste mineral product from Brazilian manganese ore mines. A pisolite sample was submitted to physical and chemical characterization; particle size analysis by screening, X-ray diffractometry, X-ray fluorescence, surface area determination by the Brunauer–Emmett–Teller (BET) method and atomic absorption spectrophotometry (AA) for the determination of the species concentration in the pisolite and in the aqueous solution samples from the experiments.Column and batch tests to contact pisolite and aqueous feed solutions were carried out for evaluation of the pisolite’s performance as a natural sorbent for arsenic removal. Experiments using activated pisolite and aqueous feed solutions prepared with Velhas River water were also performed. In the column system, 1.0 g of pisolite removed 1.41 mg of As (4.05% As extraction) from 630 ml of the aqueous feed solution and 1.0 g of activated pisolite extracted 3.51 mg of As (11.6% As extraction). Results for the batch tests with 100 ml of aqueous feed solution and 1.0 g of pisolite removed 1.29 mg of As (24.7% As extraction) and 1.0 g of activated pisolite extracted 3.17 mg (58.2% As extraction).