Fe-PG紫外光辅助活化H_(2)O_(2)流化床高效降解水杨酸

Highly efficient degradation of salicylic acid by the Fe-PG UV-assisted activation of H_(2)O_(2) fluidized bed

针对常规光催化技术催化剂回收困难,紫外/双氧水(UV/H_(2)O_(2))技术残余H_(2)O_(2)污染严重等问题,采用浸渍法制备了铁负载多孔发泡玻璃(Fe-PG)并将其用于紫外光辅助活化H_(2)O_(2)流化床降解水杨酸(SA)。结果表明,在相同实验条件下,Fe-PG紫外光辅助活化H_(2)O_(2)(UV/H_(2)O_(2)/Fe-PG)流化床工艺对SA的降解率、矿化率和H_(2)O_(2)利用率均明显优于UV/H_(2)O_(2)工艺;在考虑运行成本的情况下,最佳水力停留时间(HRT)为40 min,最佳H_(2)O_(2)投加量为3 mmol·L^(-1),最佳Fe-PG膨胀率为30%;UV/H_(2)O_(2)/Fe-PG流化床工艺对SA溶液初始质量浓度、pH和盐离子具有很强的耐受性,连续运行30 d后对SA的降解率仍维持在98%以上,矿化率仍高达78.1%。UV/H_(2)O_(2)/Fe-PG流化床工艺降解SA的主要活性物质为·OH、O_(2)^(·-)和h^(+),降解过程符合一级动力学。以上研究结果可为光催化辅助活化H_(2)O_(2)流化床技术实现工程应用提供技术支撑。

Aiming at the difficulty of catalyst recovery in conventional photocatalytic technology and serious residual H_(2)O_(2) pollution in ultraviolet/hydrogen peroxide(UV/H_(2)O_(2)) technology,iron-loaded porous foamed glass(Fe-PG) was prepared by an impregnation method,and it was used in the ultraviolet light-assisted activation of H_(2)O_(2) fluidized bed to degrade salicylic acid(SA).The results show that under the same experimental conditions,the SA degradation rate,mineralization rate and H_(2)O_(2) utilization rate by Fe-PG UVassisted activation of H_(2)O_(2)(UV/H_(2)O_(2)/Fe-PG) fluidized bed process were significantly better than UV/H_(2)O_(2).Taking operating costs into consideration,the optimal hydraulic residence time(HRT) was 40 min,the optimal H_(2)O_(2) dosage was 3 mmol·L^(-1),and the optimal Fe-PG expansion rate was 30%.UV/H_(2)O_(2)/Fe-PG fluidized bed process had a strong tolerance to the initial concentration,pH and salt ions of SA solution.After 30 days of continuous operation,the degradation rate of SA remained above 98%,and the mineralization rate was still as high as 78.1 %.The main active substances for the degradation of SA by the UV/H_(2)O_(2)/Fe-PG fluidized bed process were ·OH,O_(2)^(·-)and h^(+),and the degradation process conformed to the first-order kinetics.The research results provide a technical support for the engineering application of photocatalytic-assisted activation of H_(2)O_(2) fluidized bed technology.