十六烷基三甲基溴化铵的光降解行为研究

以阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)为研究对象,考查了水环境下光源、溶液介质、重金属离子和光敏剂等因子对CTAB光化学降解行为的影响。结果表明:1)CTAB在紫外光照射下降解率最大,20 min时的降解率为37.02%,自然光下其次,黑暗中基本不发生降解;2)20 min时CTAB在去离子水中的降解率为31.49%,比在人工海水(19.04%)中的快。3)不同重金属离子对CTAB光降解反应的影响不同,在去离子水中分别加入0.1 mg/L的Zn2+和0.1 mg/L的Cu2+,20 min时CTAB的降解率分别为29.33%和24.54%;4)光敏剂对CTAB的光降解反应有促进作用,在去离子水和人工海水中分别加入0.1 mg/L的丙酮,20 min后CTAB的降解率分别为36.92%和 22.54%。该结果可为环境中阳离子表面活性剂的有效治理提供参考。

Study on the photo-degradation of cetyltrimethylammonium bromide

The effects of light,solution medium,heavy metal ions,and typical photosensitizer under aquatic environment on the photo-degradation of cetyltrimethylammonium bromide (CTAB) ,which was selected as the typical cationic surfactant,were investigated.The results showed that:1) The degradation rate of CTAB under the UV light was the fastest compared to the rate under natural light and dark conditions,its degradability is 37.02% after 20 min,and almost no reaction in the dark.2) The degradability of CTAB in de-ionized water (31.49%) was faster than that of the artificial sea water (19.04%) .3) Different heavy metal ions have different effects on the degradation of CTAB.The degradability of CTAB was 29.33% and 24.54% after 20 min photo-degradation under the condition of 0.1 mg/L Zn²⁺ and Cu²⁺,respectively.4) The degradability of CTAB was 36.92% and 22.54% after 20 min,when 0.1 mg/L acetone was chosen as the photosensitizer in de-ionized water and artificial seawater medium,respectively.The results may be used as effective reference for the aquatic management of the cationic surfactants.