壳聚糖固化单宁微球的制备及其吸附性能

5 g单宁酸与10 g壳聚糖微球在100 mL pH=7的溶液中反应6 h,再用0.06 mol/L环氧氯丙烷在pH=10,50℃反应4 h制得壳聚糖固化单宁微球,每克壳聚糖微球固载单宁量为0.27 g。采用扫描电镜和红外光谱对微球进行了表征,考察了微球的溶胀性能及对金属离子的吸附性能。研究表明,通过此法制得的壳聚糖固化单宁微球具有表面粗糙,内部疏松多孔的结构。与壳聚糖微球相比,壳聚糖固化单宁微球在溶液中的溶胀性减小,在pH=5及9时,分别减小了63%和50%。对金属离子的吸附容量增大,对Cd2+的吸附容量从0.6 mmol/g提高到2.2 mmol/g,提高了2.66倍。

Preparation and Adsorption Properties of Chitosan Immobilized Tannin Microspheres

Chitosan immobilized tannin microspheres were prepared by stirring 5 g tannic acid and 10 g chitosan microspheres in 100 mL solution of pH=7 for 6 h,and then treated with epichlorohydrin in solution of pH=10 at 50 ℃ for 5 h.The amount of tannic acid immobilized onto 1 g chitosan microspheres was 0.27 g.Structure of the microspheres was characterized by IR and SEM.The swelling rate and adsorption properties of the microspheres were examined.The results revealed that the surface of microspheres was rough and the interior was porous.Compared with chitosan microspheres,swelling rate of chitosan immobilized tannin microspheres decreased by 63% and 50% at pH=5 and 9 respectively,and the adsorption capacity of chitosan immobilized tannin microspheres for metal ions increased,from 0.6 mmol/g to 2.2 mmol/g for Cd~2+.