Cadmium sorption properties of poly(vinyl alcohol)/hydroxyapatite cryogels: II. Effects of operating parameters

Abstract

A novel sorbent for the removal of heavy metals, hydroxyapatite/poly (vinyl alcohol) cryogel, was studied. The HAp/PVA cryogel was characteristic of macroporous structure. The experiments for Cd2+ sorption by HAp/PVA cryogel were conducted at various operating conditions such as sonication, sorption time, Cd2+ stop concentration, temperature, pH, and HAp/PVA mass ratio. It was concluded that the sorption was considerably affected by sorption time, Cd2+ concentration, temperature and HAp/PVA mass ratio. Nevertheless, there was slight dependence of sorption on sonication and pH. The influences of different parameters were discussed in detail in the paper. The main mechanism was suggested to be ion-exchange.