Synthesis of polyferromethylsiloxane sorbents using a sol-gel method

Trivalent iron complexes which could be easily converted into materials are formed by the reaction of FeCl3 with K-3[O3SiMe] in a highly concentrated aqueous alkaline solution. The presence of the liquid glass as an additive and decreasing the pH results in solutions that give rise to homogeneous gels. Polycondensation proceeds very rapidly in the higher pH range (viz. pH 9-10) and substantially slower in an acidic medium (pH 2-3). Xerogels were obtained having microporous structure after treatment of polyferromethylsiloxane gels obtained from acidic medium or mesoporous structure when obtained from alkaline medium. (C) 2001 Editions scientifiques et medicales Elsevier SAS. All rights reserved.