改性火山岩滤料对水中氨氮的吸附性能及机理研究

Study on Adsorption Performance and Mechanism of Modified Volcanic Rock Filter Media on Ammonia Nitrogen in Water

以火山岩滤料为原料,分别采用盐酸、氢氧化钠和氯化钠对改性后用于吸附水中氨氮,探讨了吸附影响因素、行为特征和吸附机理。结果表明,采用1.0 mol/L盐酸溶液改性后的火山岩滤料,在溶液初始pH值为5、投加量为1.8 g、振荡时间为8 h、氨氮初始浓度为10 mg/L时,可实现92.1%的氨氮去除,吸附量达到0.512 mg/g,比改性前增长了0.308 mg/g。动力学和等温线分析结果显示,酸改性火山岩滤料对氨氮的吸附是以化学反应为主导的多层非均匀吸附,包含了孔隙填充、氢键结合等多重复杂作用机理。酸改性火山岩滤料拥有更优异的吸附性能,可作为水中氨氮的有益吸附材料。

Volcanic rock filter media were used as raw materials for the adsorption of ammonia nitrogen in water after modifying with HCl,NaOH and NaCl solution,respectively,and the factors affecting the adsorption,behavioral characteristics and adsorption mechanism were investigated.The results showed that the modified volcanic rock filter media with 1.0 mol/L HCl solution could achieve 92.1%of ammonia nitrogen removal at an initial pH of 5,an addition volume of 1.8 g,an oscillation time of 8 h,and an initial ammonia nitrogen concentration of 10 mg/L,and the adsorption amount reached 0.512 mg/g,which was 0.308 mg/g higher than that before the modification.The results of kinetic and isothermal analyses showed that the adsorption of ammonia nitrogen by HCl-modified volcanic rock filter media was a multilayer non-uniform adsorption dominated by chemical reaction,which included multiple and complex mechanisms,such as pore filling,hydrogen bonding,and so on.The HCl-modified volcanic rock filter media possesses more excellent adsorption properties and can be used as a beneficial adsorption material for ammonia nitrogen in water.