微生物固定化吸附剂吸附Pd(Ⅱ)的研究

Study on Adsorption Characteristics of Microbial Immobilized Adsorbent for Pd(Ⅱ)

微生物法在吸附处理重金属污染和回收贵金属方面具有广阔的发展前景。利用载体A固定化大肠杆菌开发了一种高效微生物固定化吸附剂,研究其对Pd(Ⅱ)的吸附特性,构建其对Pd(Ⅱ)的动态吸附模型,并开展了循环再生实验。结果表明,吸附柱的穿透时间和耗竭时间与大肠杆菌的浓度、微生物固定化吸附剂的填充量成正相关,与溶液流速成负相关;载体A:粘结剂:大肠杆菌的质量比为4:1:3,固定化吸附剂添加量为15 g、溶液流速3 mL/min时,吸附柱对Pd(Ⅱ)有较好的吸附效率,穿透时间和耗竭时间分别为60 min和360 min;使用2 mol/L的HCl对负载Pd(Ⅱ)后吸附剂进行解吸处理,解吸率达到99.32%;吸附-解吸循环5次后,固定化吸附剂对Pd(Ⅱ)的吸附量基本保持不变。

Microbial adsorption is a method that has broad prospects in dealing with heavy metal pollution and recovery of precious metal ions.In this paper,an efficient microbial immobilized adsorbent was prepared by immobilizing E.coli with carrier A.The adsorption characteristics,dynamic adsorption model for Pd(Ⅱ),and the cyclic regeneration experiments were studied.The main results are as follows:The breakthrough time and depletion time of the adsorption column are positively correlated with the concentration of E.coli and the loading of the microbial immobilized adsorbent,and negatively correlated with the solution flow rate;When the carrier A:silicate binder:E.coli has a mass ratio of 4:1:3,the microbial immobilized adsorbent was added in an amount of 15 g and the solution flow rate was 3 mL/min,the adsorption column had a good adsorption efficiency for Pd(Ⅱ)with breakthrough time and exhaustion time are 60 min and 360 min,respectively;The desorption rate of the adsorbent after loading Pd(Ⅱ)with 2 mol/L HCl was 99.32%,which was the best.The adsorption amount of Pd(Ⅱ)by the adsorbent is almost unchanged after running the adsorption-desorption cycle for 5 times.