回收二氧化钛-膨润土对水中十二烷基苯磺酸钠的降解

DEGRADATION OF SODIUM DODECYL BENZENE SULFONATE BY REUSED TiO_2-BENTONITE

比较在6 W紫外灯照射下6 h,0.5%TiO2-膨润土及其回收二次利用时对初始浓度为20 mg/L的十二烷基苯磺酸钠(SDBS)水溶液中SDBS降解的差异,并研究了差异产生的原因,结果表明:(1)TiO2-膨润土和回收再用的TiO2-膨润土对水中SDBS的去除率分别为86.3%,46.2%,可见,回收后的TiO2-膨润土虽然对SDBS的去除效率有所降低,但可以重复使用。(2)初次使用的TiO2-膨润土及回收的TiO2-膨润土晶格结构没有明显差异。(3)回收后的TiO2-膨润土中部分Ti流失是影响其对水中SDBS去除率降低的主要原因。(4)回收后的TiO2-膨润土有机质含量明显高于TiO2-膨润土,并且,照射时间越长,回收的TiO2-膨润土有机质含量越低。在用回收后的TiO2-膨润土光催化降解SDBS过程中,被TiO2-膨润土吸附的SDBS及其中间产物,随着照射时间的增加逐渐被降解而从催化剂表面脱离。(5)用回收再用的TiO2-膨润土处理水中SDBS的过程中,水中SO42-的浓度高于催化剂初次使用时水中的SO42-浓度,SO42-主要来自SDBS的降解反应。

Difference of sodium dodecyl benzene sulfonate（SDBS） was degradated by 0.5% TiO2-bentonite and 0.5% reused TiO2-bentonite separately under 6 w ultraviolet lamp within 6h was compared.Original concentration of SDBS was 20 mg/L and the cause of difference was discussed.The results showed that：（1） Reduction of SDBS in solution which was treated by the TiO2-bentonite and by the reused TiO2-bentonite was 86.3% and 46.2% separately.Although the efficiency of reduction of SDBS treated by reused TiO2-bentonite was lower,the result showed that TiO2-bentonite can be reused.（2） Compared with the lattice structure of TiO2-bentonite,the lattice structure of reused TiO2-bentonite was not changed obviously.（3）Compare with the efficiency of SDBS reduced by TiO2-bentonite,its inefficient t reduced by reused TiO2-bentonite was that some of Ti in reused TiO2-bentonite was washed out when TiO2-bentonite was first used.（4） Contents of organic matter of reused TiO2-bentonite were higher remarkably than those of TiO2-bentonite.The longer time ultraviolet lamp shine,the lower contents of organic matter of reused TiO2-bentonite.SDBS was absorbed by TiO2-bentonite first,and then was degradated.（5） Concentration of SO42-in solution was higher when TiO2-bentonite was reused than that when TiO2-bentonite was first used.SO42-came mainly from degradation of SDBS.