模拟阳光下Ag/I-TiO_2光催化预处理山核桃加工废水

研究了在模拟太阳光下,采用银修饰的碘掺杂二氧化钛光催化剂(Ag/I-TiO2)对某食品厂山核桃加工废水进行光催化预处理的效果。结合X射线衍射(XRD)、比表面积分析(BET)、紫外-可见漫反射光谱(UV-Vis)的表征结果,来分析催化剂结构对于废水处理效果的影响。探讨了Ag含量、废水初始pH(pHi)和光照时间等因素对化学需氧量(COD)去除及水质可生化性(B/C)提高的影响。并得出适宜的反应参数为:3%Ag含量;pHi为6;光照时间为240 min。在最佳条件下,COD去除率45%,废水B/C比由0.17上升到0.31。光催化氧化法能够有效降低山核桃加工废水的COD含量,并达到显著提高废水可生化性的目的。

Pretreatment of wastewater from hickory nut manufacture used Ag/I-TiO2 under simulated solar light illumination

The effluent from the hickory nut manufacturing process was subjected to photocatalysis pretreatment with iodine-doped titania modified with silver (Ag/I-TiO₂) in artificial solar energy.In this study,the influence of catalyst properties was analyzed by X-ray diffraction (XRD),Brunauer-Emmett-Teller (BET) and UV diffused reflectance spectra (UV).Moreover,the dosage of Ag⁺ ion,the initial pH of wastewater (pH_i),and the exposure time (t) were tested for optimizing the operation parameters.The results show that the removal rate of COD was up to 45%,and the ratio of B/C increased from 0.17 to 0.31 under the optimum conditions of 3% Ag dosage,pH_i=6 and t=240 min.This clearly indicates that photocatalysis for pretreatment of hickory nut manufacturing wastewater is effective in reducing the content of COD while enhancing its biodegradability.