生物硫铁复合材料处理含铜废水及机理研究

摘要

A strain of sulfate reducing bacteria SRB2, which could generate the biological iron sulfide composites, was isolated by using the Hungate anaerobic technique. The influences of pH, temperature, stirring speed, and dosage on the removal of Cu2+ from wastewater by biological iron sulfide composites were investigated. Meanwhile the mechanism of reducing remove Cu2+ through replacement approach and EPS adsorption approach were studied. Cu2+ reduction rate increased with the increase of dosage and temperature. At 35°C, pH4.0, stirring speed of 100r/min, when the dosage of biological iron sulfide composites reached 0.6661g, the removal rate of Cu2+ could be above 99.9% within 2 min. Therefore, great prospects exist for the application of biological iron sulfide composites in the emergency treatment of copper-contaminated wastewater and heavy metal pollution. The replacement approach with a removal rate of 90.9%, predominated in the process of reducing Cu2+, while the EPS adsorption approach which removed 38% of the Cu2+ in 24 h, was not preponderant in the process of reducing Cu2+.%利用Hungate分离出一株产生物硫铁复合材料(生物硫铁)的硫酸盐还原菌SRB2,考察了投加量、pH值、温度、搅拌速度对生物硫铁处理含铜废水的影响,并分别从化学置换、胞外聚合物(EPS)吸附等途径研究了生物硫铁去除Cu2+的机理.结果表明,生物硫铁投加量越大、温度越高对铜的去除效果最好,在pH4.0、35℃、0.6661g生物硫铁、搅拌速度100r/min时,2min即可使Cu2+去除率达到99.9％以上.化学置换途径在生物硫铁去除Cu2+时占主导地位,10min去除率达90.9％,EPS吸附途径在生物硫铁去除Cu2+过程中不占优势,24h去除率为38％.