文档介绍：摘要
重金属污染已经成为当今较严重的环境问题之一,微生物吸附方法具有来源
广泛、成本低廉、吸附速度快、吸附量大、选择性高等特点,环境中大量存在的
微生物如细菌、真菌、酵母和藻类等对金属离子具有很强的吸附性。固定化微生
物作为一种新的生物吸附剂具有机械强度高、固液易分离,吸附剂易再生,能重
复利用等优点,并可制成各种类型的反应器,实现连续运行。
利用海藻酸钠固定化包埋活性炭与多黏类芽孢杆菌 GA1,通过正交试验研究
海藻酸钠溶液浓度、包炭量及包菌量吸附 Pb2+的最佳配比,并研究了这种新型的
固定化小球对 Pb2+的吸附特征。
结果表明,固定化活性炭与多黏类芽孢杆菌 GA1 小球最佳制备条件为海藻酸
钠质量分数 %、包炭量 1:20 和包菌量 1:2,在该制备条件下吸附率达到 %。
固定化小球的最佳吸附条件为 pH 5、温度 30℃和 Pb2+初始浓度 300 mgL-1,
活性炭与 GA1 经固定后对 pH、温度和 Pb2+初始浓度适应范围扩大。
吸附平衡曲线表明,对 Pb2+的吸附在 30 min 内是一个快速的过程,在 2 h 时
基本趋于平衡,且平衡曲线能较好地用 Langmuir 模型和 Freundlich 模型来描述,
其吸附过程主要为单分子层吸附,最大单分子层吸附量为 mgg-1。解吸结
果表明固定化小球能有效地循环利用。
废水中重金属离子一般是多种离子同时存在的,固定化小球同时吸附 Pb2+和
Cd2+以及 Zn2+的结果显示其他离子的存在可能影响其对另一种金属离子的吸附。
关键词:海藻酸钠;活性炭;固定化;多黏类芽孢杆菌 GA1;Pb2+;生物吸附;
同时吸附;解吸
II
Abstract
Heavy metal pollution has e to one of the serious environmental problems
today, microbial adsorption method has many characteristics, such as widely-source,
low-cost, fast-adsorption, large-adsorption, higher-selective, there is a large number of
organisms such as bacteria, fungi, yeast and algae in the environment which have
strong adsorption on metal ions. Immobilized anism as a new biological
adsorbent has an advantage of high mechanical strength, solid-liquid easy separating,
adsorbent easy regeneration, to be reused, and can produce to be various types of
reactors, and to achieve continuous operation.
Through the immobilized biosorption of activated carbon and Paenibacillus
polymyxa GA1 by sodium alginate, this paper taked advantage of the orthogonal
experiment to investigate the adsorption characteristics of sodium alginate.
According to the research, the optimal preparation conditions were as following:
the mass fraction of sodium alginate was %; the amount of carbon and bacteria was
1:20 and 1:2, respectively; under the preparation condition, the adsorption rate could
reach to %.
The adsorption conditions of the immobilized beads were: pH 5, temperature 30℃
and Pb2+