给水厂污泥改性活性炭对硝酸根的吸附性能

The adsorption characteristics of nitrate on activated carbon modified by metals extracted from water treatment residual

对原始活性炭和水厂污泥提取的金属改性的活性炭吸附硝酸盐氮的性能进行了探究。X射线荧光光谱仪(XRF)分析表明,活性炭表面负载了Al、Fe等元素,Fe的负载量为4.61 mg/g,Al的负载量为13.80 mg/g,改性后活性炭比表面积有所下降。改性活性炭对硝酸盐氮的吸附过程符合准二级动力学方程,Langmuir吸附等温式在288 K时,改性活性炭对硝酸盐氮的吸附量为2.7525 mg/g,改性活性炭对硝酸盐的吸附过程是熵增和放热的自发反应。在酸性和中性条件下,改性活性炭对硝酸盐的吸附效果较好。

The adsorption of nitrate in aqueous solution on the raw activated carbon and the activated carbon modified by metals extracted from water treatment residual was explored.XRF was showed that the surface of activated carbon was successfully loaded with Al,Fe and other elements,the loading capacity of Fe was 4.61 mg/g,and that of Al was 13.80 mg/g.The modified activated carbon has a lower specific surface area due to the loading of metal ions in the pores of the modified activated carbon.Batch tests showed that the adsorption of nitrate nitrogen on modified activated carbon fitted the pseudo-second-order model well,and the adsorption isotherm fitted the Langmuir model.At 288 K,the adsorption capacity of nitrate on modified activated carbon was 2.7525 mg/g,the process of nitrate adsorption on modified activated carbon was entropy increase and exothermic,and it was spontaneous reaction.The nitrate adsorption on modified activated carbon was better under acidic and neutral conditions.