Removal of Fulvic Acids from Aqueous Solutions via Surfactant Modified Zeolite

来源 :Chemical Research in Chinese Universities | 被引量 : 0次 | 上传用户:sb129
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
A surfactant modified zeolite(SMZ), i.e., a zeolite modified by using hexadecyl trimethyl ammonium bromide(HDTMA) was used to remove fulvic acids(FA) from aqueous solution. The effects of the relevant parameters, such as the loading level of HDTMA, the contact time, the initial FA concentration, the pH, and the types of the metal cations and organics were examined. The results show that SMZ with an HDTMA loading-level of 120% of the external cation exchange capacity(ECEC) of zeolite exhibits the best performance. Although the removal of fulvic acids by SMZ occurs rapidly within the first 30 min of the contact time, a contact time of at least 4 h is required to attain the adsorption equilibrium. The removal capacity of FA by SMZ decreases with the increase of the initial FA concentration. The pH has an effect on the FA removal efficiency because it can influence the characteristics of the FA molecules. The removal of FA is considerably enhanced by Ca 2+ or Mg 2+ ions and is adversely affected by phenol or pentachlorophenol(PCP). Under the optimum conditions, 98% of FA could be removed by SMZ. Furthermore, the desorption of FA and the regeneration of SMZ were studied. The results show that a 30% ethanol solution is sufficient for the regeneration of SMZ. A surfactant modified zeolite (SMZ), ie, a zeolite modified by using hexadecyl trimethyl ammonium bromide (HDTMA) was used to remove fulvic acids (FA) from aqueous solution. The effects of the relevant parameters, such as the loading level of HDTMA, the contact time, the initial FA concentration, the pH, and the types of the metal cations and organics were examined. The results show that SMZ with an HDTMA loading-level of 120% of the external cation exchange capacity (ECEC) of zeolite exhibits the best performance. Although the removal of fulvic acids by SMZ occurs rapidly within the first 30 min of the contact time, a contact time of at least 4 h is required to attain the adsorption equilibrium. The removal capacity of FA by SMZ decreases with the increase of the initial FA concentration. The pH has an effect on the FA removal efficiency because it can influence the characteristics of the FA molecules. The removal of FA is considerably enhanced by Ca 2+ or Mg 2+ ions and is adversely af Furthermore, the desorption of FA and the regeneration of SMZ were studied. The results show that a 30% ethanol solution is sufficient for the regeneration of SMZ.
其他文献