燃煤炉渣吸附水中铅的性能研究

Study on adsorption performance of lead from water by coal⁃fired slag

燃煤炉渣作为一种固体废弃物主要应用于建筑材料等领域。为了深入了解燃煤炉渣对水中铅的吸附性能,采用扫描电子显微镜、红外光谱和X射线衍射等方法对燃煤炉渣进行表征分析,研究了pH、添加量和底物质量浓度对燃煤炉渣吸附铅离子的影响,然后利用响应曲面法的Box-Behnken模型对其进行优化,并采用等温吸附模型对其吸附机理进行探讨。结果表明:经过响应面优化,在溶液pH为5.70、温度为45℃、铅离子初始质量浓度为233.20 mg/L时,用77.27 mg燃煤炉渣处理25 mL含铅溶液,铅离子的去除率为47.66%,且该预测值与实际值具有较高的拟合度,燃煤炉渣吸附铅离子符合Langmuir吸附等温模型,最大吸附量达143.86 mg/g。研究结果表明,燃煤炉渣作为一种廉价、高效的吸附剂,可用于铅污染废水的处理。

As a solid waste,coal‐fired slag is mainly used in construction materials and other fields.In order to gain insight into the adsorption performance of coal‐fired slag on lead in water,the characterization and analysis of coal‐fired slag were carried out by scanning electron microscopy,infrared spectroscopy and X-ray diffraction.The effects of pH,addition and substrate concentration on the adsorption of lead ions by coal‐fired slag were investigated,and the Box-Behnken model with response surface method was used for its optimization,and the isothermal adsorption model was used to explore the adsorption mechanism.The results showed that the removal of lead ions by 77.27 mg of coal‐fired slag was 47.66%at the solution pH of 5.70,the temperature of 45℃and the initial mass concentration of 233.20 mg/L in 25 mL of lead solu‐tion,and the actual value was close to the predicted value,the adsorption of lead ions by coal‐fired slag was in accordance with the Langmuir adsorption isotherm model,with a maximum adsorption capacity of 143.86 mg/g.The results of the study indicated that coal‐fired slag could be used as a cheap and efficient adsorbent for the treatment of lead‐contaminated waste‐water.