Chromium removal from water using LTA zeolites: Effect of pH

PATRICIA VÁZQUEZ; FABIO IUCOLANO; DOMENICO CAPUTO; ELENA BASALDELLA

JOURNAL OF COLLOID AND INTERFACE SCIENCE

Elsevier

Año: 2007 vol. 313 p. 574 - 579

0021-9797

The effect of pH changes on the ability of the synthetic zeolite NaA to remove Cr3+ from water by ion exchange was investigated. The exchange rate was improved by working near neutrality. Despite of the occurrence of simultaneous adsorption, precipitation or cation exchange phenomena, spectroscopic analyses of samples taken at different contact times suggested the presence of an unique chromium environment in the solid phase. The increase in pH observed during the ion exchange favored polymerization-precipitation of chromium species present in solution, which, in turn, improved the metal removal capacity of zeolite NaA above the values expected for a pure cationic exchange reaction