盐酸和硝酸介质中己二胺接枝壳聚糖微球吸附Hg(Ⅱ)的行为

制备并表征了氯化和氨化壳聚糖微球,考察了己二胺接枝壳聚糖微球(HDA-CS)在盐酸和硝酸介质中吸附Hg(Ⅱ)的行为及影响因素。结果表明,盐酸介质中,pH 3.0时,HDA-CS对Hg(Ⅱ)有较高的初始吸附速率,最大吸附容量为128.6 mg/g;硝酸介质中,pH 3.5时,它对Hg(Ⅱ)的最大吸附容量为37.7 mg/g。前者是后者的3.4倍。以1.0 mol/L的H2SO4为解吸剂,HDA-CS复用3次无溶解和流失现象。HDA-CS对Hg(Ⅱ)的吸附主要是质子化氨基与汞配阴离子以静电引力实现的。

1,6-diaminohexane-modified chitosan microspheres for adsorption of Hg（Ⅱ） in the medium of hydrcoloric and nitric acid

Ammoniation and chlorination-modified chitosan microspheres were prepared and characterized.In the medium of hydrochloric and nitric acid the adsorption behaviour and influence factors of hexamethylene diamine-modified chitosan microspheres(HDA-CS) for enhancement of Hg(Ⅱ) were investigated.The results indicated that HDA-CS had higher adsorption rate of Hg(Ⅱ) at pH 3.0,the maximum adsorption capatities were 128.6 mg/g in hydrochloric medium;but the maximum adsorption capatities were only 37.7 mg/g in nitric acid medium(pH 3.5).The adsorption capacies of the former was 3.4 times of the latter.The regeneration experimets were carried out for three cycles by using 1.0 mol/L H2SO4 solution as eluent,the adsorbent had no dissolution and running off.The adsorption of HDA-CS for Hg(Ⅱ) could be carried out by a electrostatic attaction between amino-group of peotonation the surface of on HDA-CS and the complex anion of Hg(Ⅱ) with chlorine anion.