改性高岭土吸附低含量CA-Cu的研究

Study on the Adsorption of Low Content CA-Cu by Modified Kaolin

利用3-巯丙基三甲氧基硅烷对高岭土进行改性,利用改性高岭土吸附去除模拟废水中的柠檬酸络合铜(CACu),并对比了较优条件下高岭土改性前后的吸附性能。结果表明,初始CA-Cu含量、吸附剂投加量、p H、吸附时间对改性高岭土吸附络合铜均有一定影响;在初始CA-Cu质量浓度为5 mg/L,吸附剂投加量为15 g/L,p H为5时,吸附大概在30 min达到平行,吸附率从36.1%提升至93.9%;经过改性的高岭土吸附能力有了较大提高,最大吸附量从0.19 mg/g提高到0.54 mg/g,提高了184%。改性高岭土对络合铜的吸附过程符合准2级动力学模型和Langmuir等温吸附模型。

The kaolin was modified by 3-mercaptopropyl trimethoxysilane to obtain modified kaolin, which applied as adsorbent for low content citric acid-complexing copper （CA-Cu） removal in simulated wastewater. The adsorption performance of kaolin before and after modification was compared. The results showed that, initial CA-Cu content, adsorbent dosage, initial pH and adsorption time had some effect on complexing copper adsorption by modified kaolin. Optimal control parameters were initial mass concentration of CA-Cu was 5 mg/L, adsorbent dosage was 15 g/L and pH was 5, the reaction reached equilibrium after 30 min adsorption, and the removal efficiency of CA-Cu increased from 36.1% to 93.9%. The maximum adsorption capacity of modified kaolin increased from 0.19 mg/g to 0.54 mg/g which increased 184%. The complexing copper adsorption process by modified kaolin conformed to pseudo-second-order model and the Langmuir isothermal adsorption model well.