用枯草芽孢杆菌吸附去除电镀废水中的铜

Removal of Copper From Electroplating Wastewater by Microbial Adsorption of Bacillus Subtilis

通过筛选和培育,从某电镀活性污泥中得到一株高效耐Cu^(2+)功能吸附菌,根据菌落形态特征及16S rDNA序列测定和比对,鉴定出该菌株为芽孢杆菌属中的枯草芽孢杆菌(Bacillus subtilis-TR1)。研究了用此菌种从电镀废水中吸附去除Cu^(2+),考察了废水初始pH、Cu^(2+)初始质量浓度、温度、菌种加入量、培养时间及摇床转速等对Cu^(2+)去除率的影响。结果表明:在废水初始pH=5、Cu^(2+)初始质量浓度80 mg/L、温度30℃、细菌接种量3 g/L、培养时间48 h条件下,此菌种对Cu^(2+)有较好的吸附去除效果,Cu^(2+)去除率达62.4%,吸附量达4.02 mg/g;主要吸附机制为通过自身表面的功能基团和静电引力,诱导废水中Cu^(2+)发生迁移和离子交换,与表面功能基团结合形成典型非晶相结构配合物,进而将Cu^(2+)去除。研究结果为电镀污泥的源头减量提供了一种可用吸附材料,可为电镀废水的微生物处理提供参考。

A Cu^(2+)functional adsorption resistant strain was obtained from electroplating activated sludge through screening and cultivation.The strain was identified as Bacillus subtilis-TR1 based on the morphological characteristics of the colony and 16S rDNA sequence determination and comparison.The adsorption removal of Cu^(2+)from electroplating wastewater by Bacillus subtilis-TR1 were studied.The effects of wastewater initial pH,initial mass concentration of Cu^(2+),temperature,strain adding amount,culture time and shaking speed on Cu^(2+)removal were investigated.The results show that under the conditions of wastewater initial pH of 5,Cu^(2+)initial mass concentration of 80 mg/L,temperature of 30℃,strain adding amount of 3 g/L,and culture time of 48 h,the strain has a good adsorption and removal effect on Cu^(2+),the removal rate of Cu^(2+)is 62.4%,adsorption capacity is 4.02 mg/g.The main adsorption mechanism is to induce the migration and ion exchange of Cu^(2+)in the wastewater through the functional groups on the surface and electrostatic attraction,and combine with the functional groups on the surface to form a typical amorphous phase structure complex,and then remove Cu^(2+).The research results provide a usable adsorption material for the source reduction of electroplating sludge,and provide a reference for the microbial treatment of electroplating wastewater.