COMPARISON OF METAL UPTAKE PROPERTIES OF SILICA GEL-BOUND ION-EXCHANGERS AND SOME AMINE DERIVATIVES

Silica gel bound to some amine derivatives such as semicarbazide, thio semicarbazide, ethylenediamine and phenylenediamine as well as ion exc hangers containing carboxylic groups derived from phthalic anhydride a nd succinic anhydride were synthesized and their metal-uptake properti es in aqueous solution were studied. The factors controlling and influ encing the metal uptake capacity, such as shaking time and pH of the m etal ion solution, were also determined to evaluate and compare the pe rformance toward metal ion extraction. The data in this study show tha t the values of metal capacity of the silica gel-bound complexing agen ts are higher than those of the ion exchanger analogs, and those of th e immobilized aliphatic diamines or acid derivatives are higher than t he corresponding values of aromatic analogs. A method of recycling the synthesized phases after metal extraction processes, for the sake of further and successive use of the recycled phases, is also presented.