硅胶改性壳聚糖膜的制备及其对Cu2+的吸附性能

重金属是水体中十分严重的生态环境污染之一,而壳聚糖具有较强的重金属吸附能力。采用硅胶粒子浸出法制备出大孔壳聚糖膜,并且研究了其对重金属Cu^2+的吸附性能。发现3.0g壳聚糖溶于10%(质量分数)的乙酸溶液中,加入3.0g硅胶再经过戊二醛交联后制备出大孔壳聚糖膜的吸附能力较好。在40mL、400mg/L的CuSO4溶液中,加入0.4g制备好的壳聚糖膜,经过25h后,壳聚糖膜呈蓝色,用紫脲酸铵指示反应为紫色,吸附率为93%。说明壳聚糖膜对Cu2+具有良好的吸附能力,吸附过后膜很容易从溶液中取出,克服了传统的吸附剂在溶液中固液分离困难的问题。

Preparation of chitosan membrane modified by silica gel and its absorption properties for Cu2+ removal

Heavy metal contaminant in water resource is one of considerable reason to cause serious water pollution in ecological environment.Chitosan has strong adsorption for heavy metals.Macroporous chitosan membrane was prepared by silica gel particle leaching method.Adsorption performance for Cu²⁺ was studied as well.By adding 3.0 g silica gel into 10%（mass fraction） acetic acid solution with 3.0 g chitosan dissolved in advance,a macroporous chitosan membrane with good adsorption property ultimately was prepared after cross-linking with glutaraldehyde.The 0.4 g prepared chitosan membrane was put in 40 mL,400 mg/L CuSO₄ solution,the membrane turned into blue after standing 25 h,the color of the solution transform into purple when murexide was used as indicator in chromogenic reaction,and the adsorption efficiency of Cu²⁺ was 93%.It demonstrated that the chitosan membrane had good adsorbability for Cu²⁺ and the membrane was easily separated from the solution after adsorption,which overcame the problem that the conventional adsorbent was difficult to separate solid and liquid in solution.