亚甲基蓝在有机酸膨润土上的吸附行为

Adsorption behavior of methylene blue on citric acid bentonite

为了解决染料废水带来的污染问题,采用柠檬酸对天然膨润土(RB)直接改性,制备柠檬酸膨润土(CAB),并探讨了溶液p H值、表面活性剂对CAB去除亚甲基蓝(MB)的影响。研究结果表明,CAB在去除MB方面有很宽的p H适宜范围,溶液p H值对CAB去除MB的影响不大;MB溶液中加入十二烷基苯磺酸钠(SDBS)以后,CAB对MB的去除率基本保持不变,而十六烷基三甲基溴化铵(CTAB)的加入则明显抑制CAB对MB的去除;MB在CAB上的吸附同时符合Langmuir和Redlich-Peterson模型,CAB对MB的Langmuir吸附容量为252 mg/g;CAB表面的羧基和羟基是吸附MB的主要吸附位点。研究表明,CAB是一种在染料的去除方面非常有应用前景的吸附剂。

To solve the serious water pollution by dye wastewater,citric acid bentonite( CAB) was obtained by modifying raw bentonite( RB) with citric acid directly and its adsorption performance of methylene blue( MB) was studied as a function of p H and surfactants. It was found that p H had little effect on MB adsorption so CAB had a broad p H range for MB removal. The removal efficiencies of MB on CAB in the presence of sodium dodecylbenzenesulfonate( SDBS) were kept constant while those in the presence of cetyltrimethylammoniun bromide( CTAB) were obviously restrained. MB adsorption on CAB could be described by the Langmuir and Redlich-Peterson models and the respective Langmuir adsorption capacity was 252 mg / g. The groups of carboxyl and hydroxyl were the major adsorption sites for MB removal. In summary,the study suggests that CAB is a promising adsorbent in dyes removal from aqueous solution.