Influence of acetate, chloride and nitrate ions on the sorption of cobalt by zeolite ZSM-5

Many factors affect the ion exchange process in zeolites. In this work the influence of different anions such as acetate, chloride and nitrate on the ion exchange of cobalt in zeolite ZSM-5 is discussed. After the ion exchange in the presence of those anions no change was found in the zeolite structure, by X-ray diffraction and IR spectroscopy. The retention of cobalt by zeolite ZSM-5 at low concentrations (from 0.001 to 0.3N) was higher when the exchange was done with cobalt nitrate and chloride. This behavior was different in the case of 1N cobalt salts, since the highest sorption uptake was found when working with cobalt acetate and its sorption was directly proportional to its concentration. (author)