Adsorption of mercuric chloride and phenylmercuric acetate from aqueous solution using chitosan flakes

Abstract

In this study, removal of mercury compounds from aqueous solution by adsorption was investigated. Adsorbents were chitosan 79%, chitosan 87% and chitosan 95% degree of deacetylation. A set of experiments was conducted at atmospheric pressure; initial solution pH of 5, 6 and 7, and temperature of 10℃, 30℃ and 50℃. Mercuric chloride and phenylmercuric acetate were selected as models of inorganic and organic forms of mercury compounds. Mercury compounds were dissolved in distilled water to obtain feedstock solution that contained 10 ppm of mercury. The results show that all three types of chitosan can be used to remove both mercuric chloride and phenylmercuric acetate from aqueous solution. Removal of mercury compounds depends on type of mercury compounds. Removal of mercuric chloride depends on initial pH of the solution and operating temperature. Ability of chitosan on adsorption of mercuric chloride decreased with increasing initial pH of solution. Removal of phenylmercuric acetate in some condition depends on initial pH of the solution and operating temperature. Ability of chitosan on removal of phenylmercuric acetate is slightly decreased with increasing initial solution pH and slightly increased with increasing operating temperature. Removal of mercuric chloride at some condition depends on degree of deacetylation. Ability of chitosan on removal of mercuric chloride slightly increased with increasing degree of deacetylation. Effect of degree of deacetylation on removal of phenylmercuric acetate cannot be concluded.