怀海霞 张秀秀 李少华 薛秀恒

摘要探讨了活性炭（AC）负载的TiO2对蔬菜中残留的农药乐果的光催化降解作用。采用Sol-Gel法在酸性条件下制备TiO2和AC负载的TiO2（TiO2/AC），并用钼酸铵分光光度法测定光催化降解前后乐果溶液的浓度。结果表明，室温下TiO2降解乐果的最适时间为4 h，最适TiO2质量浓度为1 000 mg/L，最适降解pH为11。AC负载的TiO2复合物显著提高了TiO2对乐果的降解率;在复合物中，每30 mL TiO2溶胶中AC的最佳加入量为1 g;负载型复合物的降解作用对蔬菜的营养成分影响不大。由此得出结论：负载型AC/TiO2复合物能更有效地降低乐果的残留。

关键词乐果;TiO2;活性炭负载;光催化降解;蔬菜

中图分类号X592文献标识码A

文章编号0517-6611（2020）04-0164-04

doi：10.3969/j.issn.0517-6611.2020.04.048

开放科学（资源服务）标识码（OSID）：

Photocatalytic Degradation of Residual Dimethoate in Vegetables by Activated Carbon Loaded Titanium Dioxide

HUAI Hai-xia1，ZHANG Xiu-xiu2，LI Shao-hua2 et al（1.Institute of Physical Science and Information Technology of Anhui University，Hefei，Anhui 230000;2.School of Tea and Food Science and Technology，Anhui Agricultural University，Hefei，Anhui 230000）

AbstractThe photocatalytic degradation of dimethoate by activated carbon supported titanium dioxide （TiO2） was studied.TiO2 and activated carbon loaded TiO2 （TiO2/AC） were prepared by Sol-Gel under acidic conditions.The concentration of dimethoate solution before and after photocatalytic degradation was determined by ammonium molybdate spectrophotometry.The results showed that the optimum time for dimethoate degradation by TiO2 at room temperature was 4 h，and the optimum TiO2 concentration was 1 000 mg/L andpH was 11.Activated carbon loaded TiO2 complex significantly increased the effect of TiO2 on dimethoate.In the complex，the optimum amount of activated carbon per 30 mL TiO2 sol was 1 g，and the degradation of loaded complex had little effect on the nutritional composition of vegetables.It is concluded that the loaded activated carbon/TiO2 complex can reduce the residue of dimethoate more effectively.

Key wordsDimethoate;TiO2;Activated carbon loading;Photocatalytic degradation;Vegetable

有機磷农药残留问题已引起全世界的关注，各国科研工作者也在不同领域对农药残留问题进行了研究。乐果[O，O-二甲基-S-（N-甲基氨基甲酰甲基）二硫代磷酸酯]是被大量用于农业的有机磷农药，主要用于对果树和棉花进行杀虫。农药的光催化降解是其在植物表面和环境中的主要降解途径[1-2]。

光催化技术对有机农药的降解是目前环境领域中新兴研究课题。饶志等[3]在关于有机农药光催化降解研究进展的研究中表明，在半导体纳米粒子和光催化体系组合作用下，有机农药均可得到有效的降解。近年来，以TiO2半导体作为光催化材料来降解各类有机污染物的研究有较多报道;对用TiO2光催化降解农药废水也进行了相关研究，并取得了较好进展[4]。Betancourt-Buitrago利用TiO2和清除剂对合成矿废水进行缺氧光催化处理，回收络合氰化物取得了良好的成效[5]。……