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›› 2006, Vol. 6 ›› Issue (3): 369-374.

• 反应与分离 • 上一篇    下一篇

乳状液膜系统稳定性的显微研究及Cr(VI)离子分离效率分析

文利雄,赵旻,程靖,高瑞发,陈建峰   

  1. 北京化工大学纳米材料先进制备技术与应用科学教育部重点实验室
  • 出版日期:2006-06-20 发布日期:2006-06-20

Microscopic Study on Stability of Emulsion Liquid Membrane and Extraction Efficiency of Cr(VI) from Wastewater

WEN Li-Xiong,ZHAO Min,CHENG Jing,GAO Rui-fa,CHEN Jian-feng   

  1. Key Lab for Nanomaterials, Ministry of Education, Beijing University of Chemical Technology
  • Online:2006-06-20 Published:2006-06-20

摘要: 采用毛细显微摄像技术,对乳状液膜系统的稳定性进行了微观研究并分析了稳定性对液膜分离效率的影响. 实验中将含重金属离子Cr(VI)的工业废水作为外水相,采用TBP-Span80-煤油体系作为油膜相,NaOH溶液作为内水相,制备了单个W1/O/W2型双重乳液颗粒系统,通过显微镜直观、实时地观察不同组成的双重乳液系统的稳定性,同时采用此乳状液膜体系对废水中的Cr(VI)进行了去除实验,将实验与机理研究相结合,通过研究pH值、表面活性剂、载体及内水相组成等对乳状液膜稳定性和Cr(VI)提取率的影响,阐明了液膜稳定性与液膜法去除Cr(VI)的分离效率之间的内在联系. 实验结果表明,在选择条件下,经过一次性处理10 min后,Cr(VI)的提取率可达99.3%以上,残余质量浓度降至0.5 mg/L,达到国家排放标准.

关键词: 乳状液膜, 稳定性, 废水处理, 六价铬去除

Abstract: Using a capillary video microscopy technique, the stability of TBP-Span80-kerosene emulsion liquid membrane (ELM) system was investigated by preparing a single W1/O/W2 double emulsion globule. The efficiency of ELM for removing Cr(VI) was also studied. Combining these two experiments, the effects of pH, Span80, TBP and NaOH on both the stability and Cr(VI) extraction efficiency were analyzed. It was found that the oil-soluble surfactant was the key factor for the ELM stability and the system stability was enhanced with increasing surfactant concentration. In order to remove Cr(VI) effectively with ELM, the surfactant concentration must be above the minimum concentration required for the stability of ELM. Acidity reduces the stability, but it is required for the removing process, and it is favorable to the oil-water separation after the reaction. Tributyl phosphate (TBP) has no remarkable impact on the stability, however, NaOH in the internal water phase has great effect on both stability and Cr(VI) extraction efficiency. There are optimal values for all these factors to achieve the best Cr(VI) removing performance, and the extraction efficiency of Cr(VI) can exceed 99.3% after a single treatment step.

Key words: emulsion 1iquid membrane, stability, wastewater treatment, Cr(VI) removal