阴离子表面活性剂与铝盐复合絮凝去除苯甲酸

Synergistic Flocculation of Anionic Surfactant and Aluminum Salt to Remove Benzoic Acid

阴离子表面活性剂废水与铝盐(Al_2(SO_4)_3)的絮凝反应可以同时去除阴离子表面活性剂及其共存有机物。通过构建十二烷基硫酸钠(sodium dodecyl sulfate,SDS)与苯甲酸(benzoic acid,BA)的共存体系,研究了初始SDS浓度、Al盐投加量及pH对SDS和BA去除的影响,为絮凝反应条件的优化提供参考。结果表明:SDS浓度越大,胶束形成量越多,有利于SDS和BA的去除;Al可与BA形成络合物,Al盐浓度的增大有利于BA去除,但高浓度的Al离子会增大溶液离子强度,减弱其与SDS的结合能力,SDS去除率不会显著增加;pH会影响Al盐水解和BA解离,低pH不利于BA的去除,高pH既不利于SDS的去除,也不利于BA的去除,最佳pH范围为4.0~5.0。

Adsorptive micellar flocculation（AMF） of anionic surfactant and aluminum salts（Al2（SO4）3） is an effective method for the removal of anionic surfactants and other organic pollutants. In this study, a coexisting system of sodium dodecyl sul-fate（SDS） and benzoic acid（BA） was constructed to investigate the influence of initial SDS concentration, aluminum salts dosage and pH on the removal of SDS and BA. Results showed that higher the concentration of SDS, more the number of mi-cellar, thus promoting the removal of SDS and BA; an increase ofaluminum salt concentration was favorable to BA removal due to the formation of complex of Al and BA; however, high aluminum salt concentration could enhance the ionic strength of the solution, which might reduce the bonding of Al ions with SDS, and as a result, the removal efficiency of SDS was not much improved. As to influence of pH value, removal efficiency of BA declined at low pH while that of SDS and BA both decreased at high pH owing to that pH would affect the hydrolysis of aluminum salt and the dissociation of BA; preferably,the proper range of pH was 4.0~5.0.