δ-FeOOH对刚果红的吸附及光催化降解

Adsorption and photocatalytic degradation of Congo red byδ-FeOOH

通过化学还原法合成了δ-FeOOH,对其物理性质和微观结构进行了表征。以偶氮废水中的刚果红(CR)为模拟污染物,研究了CR初始质量浓度、催化剂用量、反应时间和H2O2投入量对δ-FeOOH吸附及光催化降解CR活性的影响。实验结果表明:δ-FeOOH为非晶态、呈片状,比表面积高达402.5 m^(2)/g;在CR质量浓度250 mg/L、δ-FeOOH用量20 mg时,6 h后CR的脱除率为100%,吸附量为1225 mg/g,可循环吸附5次;在CR质量浓度为250 mg/L的废水中,δ-FeOOH用量为30 mg时,在可见光下照射40 min,CR的降解率达99%以上,经5次循环使用后,光催化降解率仍可达99%。

δ-FeOOH was synthesized by chemical reduction method,and its physical properties and microstructure were characterized.The adsorption and photocatalytic degradation of Congo red(CR)were studied by UV-Vis spectrophotometer.Taking the common Congo red in azo wastewater as a simulated pollutant,the effects of Congo red initial mass concentration,catalyst dosage,reaction time,and amount of hydrogen peroxide on the adsorption ofδ-FeOOH and the photocatalytic degradation of CR were studied.The results showed thatδ-Fe00H was amorphous and sheet structure,with a specific surface area up to 402.5 m^(2)/g.Under the conditions of CR mass concentration of 250 mg/L and 3-Fe00H dosage of 20 mg,the removal rate of CR after 6 h was 100%,the adsorption capacity was 1225 mg/g,and the adsorption cycle could be 5 times.In wastewater with the mass concentration of CR of 250 mg/L,and the amount of catalystδ-Fe00H of 30 mg,the degradation rate of CR was 99%under UV light for 40 min.Furthermore,the photocatalytic degradation rate could still be as high as 99%after 5 cycles.