酸改性膨润土对含铅废水的吸附性能研究

Study on Adsorption of Pb^(2+) in Wastewater by Acid-Modified Bentonite

以硫酸为改性剂,对钙基膨润土进行活化改性,考察了改性剂用量、改性膨润土加入量、吸附时间以及pH值等因素对改性膨润土去除模拟水样中重金属离子Pb2+的影响。结果表明,用体积浓度为20%的硫酸溶液改性后的膨润土的除铅效果最好,在常温下,当改性膨润土用量为15g/L,吸附时间为30m in,pH值为6~9时废水中铅的去除率最大,超过99.5%,处理后铅的剩余浓度小于1mg/L,达到国家第一类污染物排放标准。

Calci-bentonite was modified with using sulfuric acid as the modifier. The effects of various parameters on modified bentonite removing Pb^2＋ in simulate water were investigated, such as modifier amount, dosage of acid - modified bentonite, the adsorption time and the value of pH. The resuits showed that the bentonite modified by 20% volume concentration sulphuric acid solution had the best adsorption ability. At normal temperature, the removal rate of Pb^2＋ can reach more than 99.5 % under the following conditions： the dosage of acid - modified bentonite is 15 g/L, the adsorption time is 30min, the pH value is 6 - 9. The rest concentration of lead is lower than 1 mg/L and it can meet the national standard of contamination discharge.