Photocatalyzed Degradation of Agrochemicals in TiO2 Aqueous Suspensions

The photocatalyzed degradation of ten agr㏄hemicals(simazine，benthi㏄arb，thiram，diazinon，fenitrothion， isoprothiolane，propyzamide，dichlorvQs，fenobucarb，and iprobenfos)has beξシn investigated in an aqueous suspension of TiO2using a ultra high-pressure mercury lamp(λ＞290nm)。The degradation is much faster than direct photolysis without TiO2and depen(1s on the structures of the agr㏄hcmicals、As for iprobenfos，the effects of light intensity，wavelength，initial concentration，partial pressure of O2in bubbling gases，reaction temperature，㎝d pH on the degmdation rate are examined and a kinctic equation is proposed to explain the experimental results，Several intermediates and probable pathways of the(1egradation are also proposed。