十二烷基苯磺酸钠的超声降解研究

采用频率为１．８ＭＨｚ，声强近似为５Ｗ·ｃｍ~－２的超声波，在固定式声化学的应器内研究了初始浓度为２００ｍｇ／Ｌ－４００ｍｇ／Ｌ的十二烷基苯磺酸钠（ＤＢＳ）溶液的声化学降解情况．实验表明，浓度的改变对ＴＯＣ的削减率无明显的影响，溶液的ＰＨ值对降解率则有显著影响，碱性条件下（ＰＨ＝１３），ＤＢＳ几乎无降解，酸性条件下（ＰＨ＝３）ＴＯＣ削减率≤１０％．通过分析降解过程中溶液的紫外光谱（１９０－３４０ｎｍ），发现降解过程中有复杂的中间产物生成，包括小分子烃类碎片及硝基化合物。我们认为，能使溶液表面张力。降低的表面活性剂，其声化学降解率低的原因在于，溶液表面张力下降后影响了溶液中空化效应的产生，从而降低了溶液中声化学反应的强度，致使ＴＯＣ削减率不高。

The degradation of DBS by sonochemstry

Ultrasonic waves of frequency 1.8MHz, intensity of rougrly 5W.cm-2 were used to treat DBS solution of concentration ranging 0.2-4.0/Lin a sono-chemical reactor. The experimental results show that changes of concentration of DBS haveno influence on TOC removal rate. In basic solution(PH=13), no degradation appears, while in acidc: solution(pH=3), the TOC removal rate reaches upto 10%. The intermediate products were analysed by using ultraviolet spectrum scanned in the 190-320nm range, and were found to include piecesof broken chain of hydrocarbon and nitric benzene. The degradation mechanism were also analysed. we believe that the surface active regents in solution could reduce the sarface tension of the concerned liquid and thus weaken the generatien of cavitation in the solution to cause the low removal rate of TOC.