一株微杆亚铁氧化菌Microbacterium sp.W5对水中铜离子的吸附行为研究

Adsorption of Cu^(2+) from Aqueous Solution by a Fe-oxidizing Bacterium Microbacterium sp.W5

研究了一株硝酸盐还原型厌氧亚铁氧化菌代谢过程中产生的生物铁氧化物对水中重金属Cu^(2+)离子的吸附。通过实验发现,在pH值为5.0的时候,吸附剂对Cu^(2+)离子的吸附量最大。在吸附剂量相同的情况下,初始离子浓度越高,吸附剂的吸附量越高。Cu^(2+)的吸附热力学很好的符合了Langmuir吸附等温模型,相关系数为0.99。其吸附动力学更符合准二级动力学,吸附剂对Cu^(2+)的吸附属于化学吸附。此外还利用傅里叶红外光谱对其吸附机理进行了初步推断。

A newly isolated Fe-oxidizing bacterium Microbacterium sp. W5 is used in this study to adsorpt Cu2＋ from aqueous solu-tions. It can be found that the adsorption capacity increases along with the increasing pH and reaches its maximum when the pH is 5.0. In addition, higher Cu2＋ concentration can enhance the adsorption capacity while the adsorption efficiency is demoted. The ad- sorption behavior fits well with Langmuir isotherm with the correlation coefficient 0. 99. The biosorption mechanisms are investiga- ted with pseudo-first-order, pseudo-second-order, the results exhibit a good compliance with the pseudo-second-order equation with a high coefficient（R2 =0. 997 1）. The mechanism is investigated by the FTIR.