Some physicochemical properties of perlite as an adsorbent

Abstract

Perlite is a glassy volcanic rock, which will, upon rapid controlled heating, expand into a frothy material of bulk density. Considering the fact that the uses of perlite are based primarily upon its physical and chemical properties, it is aimed to investigate some physical and chemical properties of unexpanded and expanded perlite. Structural changes occurring during the expansion of perlite are discussed.During the expansion a transition from amorphous structure to a crystalline form has been found to occur, and also some part of water has been removed, but there has still been some water in crystal lattice. Acid activation has caused a little increase in cation exchange capacity of perlite, while the density has remained almost unchanged.