【作者】 黄焕标；

【导师】 尹平河；

【作者基本信息】 暨南大学 ， 分析化学， 2009， 硕士

【摘要】 CTAB的降解及其微污染水体的修复研究摘要随着工业的发展,表面活性剂的消耗量急剧增加,导致表面活性剂废水大量进入到环境中,给生态环境带来严重的污染和危害。在表面活性剂中季铵盐类阳离子表面活性剂毒性最大,对微生物有强烈的抑制作用,在环境中不易生物降解,同时还可以抑制其它污染物的降解,因此研究季铵盐表面活性剂的降解有着重要的意义。本课题研究了十六烷基三甲基溴化铵（CTAB）在不同方法下的降解。首先,探讨了Fenton氧化法降解水体中的CTAB的影响因素。研究当CTAB浓度为20mg·L^-1时, Fenton法降解CTAB的最佳工艺条件为:H₂O₂用量在8mg·L^-1时,溶液pH为3.5,Fe²⁺质量浓度20mg·L^-1。在降解产物中有CHOOH生成。在H₂O₂用量较低时,Fenton氧化法无法对CTAB最终矿化。然后,探讨了高压汞灯紫外光（UV）/Fe³⁺对CTAB的光降解过程,发现UV/Fe³⁺降解CTAB符合一级动力学规律。降解过程受反应温度,质量浓度,溶液pH值影响。25℃时,在溶液pH为3.0-3.5,降解速率常数k随/Fe³⁺浓度增大而增大,在Fe³⁺浓度为7mg·L^-1时达到最大。在降解产物中可以检出CHOO^-,CH₃COO^-,CH₃CH₂COO^-,在时间足够长时UV/Fe³⁺处理可以使CTAB彻底降解。最后,研究了CTAB在模拟海水和赤潮环境的降解。CTAB在无光海水中水解较为缓慢,25℃时18d降解率仅达2.25%;40℃时为18.25%。在光的作用下CTAB降解速率明显加快,25℃时,18d降解率可达32.9%,40℃时为45.8%。在模拟赤潮环境中,CTAB可以快速降解。当投加量为40mg·L^-1时,经过72小时后,水体中无检出CTAB。更多还原

【Abstract】 Consumption of surfactant increase greatly as the development of industry, large amount of surfactant polluted water was disposal in the environment,results in contanmination and potential risk.Cationic surfactant such as quaternary ammonium salt is toxic persistent organic pollutants, it’s able to inhitit the degradation of other contamination.As as result, researh on the degradation has important significance.In this thesis, the degradation of cetyl trimethyl ammonium bromide （CTAB） by different method was studies.First, degradation of CTAB by Fenton process was studied. influencing factors such as, dosage of H₂O₂, pH value,concentration of Fe²⁺ were also investigated. The optimal conditions when the concentration of CTAB is 20mg·L^-1 were as follows: H₂O₂ dosage 8 mg·L^-1, Fe²⁺20 mg·L^-1,pH value 3.5. CHOOH was detected in the degradation product.Under the optimal condition, CTAB was primary but not finaley degradated becouse of low H₂O₂ dosage.Second, degradation of CTAB by Fe³⁺/UV photocatalysis was studied. Results shown that the degradation of CTAB by Fe³⁺/UV photocatalysis was psedo-first order kineitc.The first order reaction rate constant k was influenced by Fe³⁺,CTAB concentration, pH, temperature and other ions the solution, vared from0-0.18 min^-1when the initial of CTAB was 20 mg·L^-1 and temperature is 25℃.when is concentration of Fe³⁺ is 7 mg·L^-1, k reached the maxmum, and decreased when the concentration of Fe³⁺ above 7 mg·L^-1.CHOO^-,CH₃COO^-,CH₃CH₂COO^-, NO₂^- was detected in the degradation produts by IC ion chromatography, assumed degradation passway was discussed based on the products.CTAB can be finally degradation in a certain reaction time.Finaly, degradation of CTAB in sea water and simulated red tide was studied, the hydrolysis of CTAB in dark sea water under processed slowly,at 25℃and 40℃percent hydrolysis reached only 2.25 and 18.25, respectively. With exsit of light, under the above conditaion percent hydrolysis reached 32.8% and 45.8%, respectively.In the simulated red tide environment, CTAB was able to degradate rapidly, when the dosage of CTAB was 40 mg·L^-1, no CTAB was detected in 72h, which means CTAB is an efficiential and easy-degradated algaecide.更多还原