Removal of Inorganic–Organic Bound Cu(II) from Different Aqueous Solutions by New Adsorbents Synthesized by Sol–Gel Process

Abstract

Hydrolysis product of alcohol modified titanium(IV)‐n‐propoxide and its coated form were prepared as new and regenerable adsorbents for adsorbing and removing Cu(II) ions from its different aqueous solutions. The hydrolysis and alcoholysis products and adsorbents were characterized using GC, 1H‐NMR, FT‐IR, SEM, and TG‐DTA analysis. It was found that Cu(II) ion adsorption rather increased when hydrolysis product of alcohol modified titanium(IV)‐n‐propoxide was coated with prehydrolyzed 3‐mercaptopropyltrimethoxy silane in n‐propanol and this coated material was used as adsorbent. Depending on the results of experiments performed at optimum conditions of initial Cu(II) concentration, amount of adsorbent, contact time, and pH, maximum adsorption of Cu(II), i.e., >98% has been achieved under the non‐competitive conditions, while almost 60% is achieved under the competitive conditions of Pb(II), Zn(II), Fe(III), and alkali and earth alkali metals. It was also concluded that Cu(II) adsorption efficiency is not affected from the media containing acetate, tannic acid, or Turkish Blue dye. The adsorbent was easily regenerated with 5 N HNO3 solution and used over and over again for the adsorption of Cu(II) ions.