光催化降解炼化反渗透浓水的动力学特性和影响因素

The dynamic characteristics and the influencing factors of photocatalytic degradation of refinery concentrated water of RO

以难生化处理的炼厂反渗透(RO)浓水为降解对象,考察反应时间、pH、催化剂投加量等对悬浮体系纳米TiO_2(P25)光催化降解RO浓水的影响,并对光催化降解RO浓水的动力学模型和吸附模型进行研究。结果表明,在低压汞灯光照8 h,光催化剂投加量为1 g/L,pH为4.5时,CODCr最高去除率达到47.51%;在不同pH下催化剂的吸附过程符合准二级动力学方程,平衡吸附量随pH增大而减小;光催化降解过程随反应时间遵循Langmuir-Hinshelwood动力学模型,反应符合准一级反应动力学方程。经光催化处理后,RO浓水B/C值从0.01提高到0.22,可生化性显著提高,为后续生化处理创造条件,也为光催化技术应用于难降解工业污水提供借鉴和参考。

The actual difficult biochemical treatment refinery reverse osmosis（RO） concentrated water as the degradation object,the effects of reaction time,pH,catalyst dosage and other influencing factors on the photocatalytic degradation of RO concentrated water in the suspension system of nano TiO_2（P25） are investigated,and the kinetic model and the adsorption model of photocatalytic degradation of RO concentrated water are studied.The results show that the highest removal rate of CODCrreaches 47.51% when UV germicidal lamp lights 8 h,the dosage of photocatalyst is 1 g/L and pH is 4.5,and the adsorption process under different pH conditions accords with the quasi-second-order kinetics equation,the equilibrium adsorption capacity decreases with the increase of pH;The photocatalytic degradation process followed the Langmuir-Hinshelwood kinetics model with the reaction time,and the reaction accords with the pseudofirst-order reaction kinetics equation.After photocatalytic treatment B/C value of the RO concentrated water increased from 0.01 to 0.22,the biodegradability has significantly improved,to create conditions for the subsequent biological treatment,also for photocatalytic technology applied in the actual refractory industrial sewage to provide references.