共存Fe3+对水中腐殖酸/牛血清蛋白臭氧氧化过程的影响

为探索管道腐蚀产物对供水系统典型有机污染物臭氧氧化过程的影响, 采用模拟含金属离子Fe3+与腐殖酸/牛血清蛋白的试验水, 进行均相催化臭氧氧化试验. 结果表明, 臭氧氧化腐殖酸的效率大于牛血清蛋白, 持续氧化60min, 两者去除率分别达61.9%与13.8%; Fe3+的存在对臭氧氧化腐殖酸和牛血清蛋白表现出了不同影响, 前者去除率随Fe3+投加量的增大而降低, 最大由57.6%降至46.0%, 后者去除率随Fe3+投加量的增大而升高, 最高由12.4%升至40.0%. Fe3+共存条件下, 两种污染物溶液的Zeta电位绝对值及其颗粒平均粒径均在臭氧氧化后降低; 腐殖酸与Fe3+间存在明显的凝聚作用, 其颗粒平均粒径在Fe3+投加后明显增大, 而牛血清蛋白与Fe3+间无明显凝聚, 其颗粒平均粒径变化不大. 对臭氧氧化有机污染物的机理展开讨论, 表明腐殖酸与Fe3+间的凝聚作用会抵消臭氧氧化过程中Fe3+的催化作用. 由此推论, 管道腐蚀产生的金属离子Fe3+对终端管网二次污染控制具有一定的积极作用, 包括通过催化臭氧氧化作用以强化蛋白质污染物的降解, 通过凝聚作用在过滤过程中协同去除腐殖质污染物.

Effect of coexisting Fe3+ on catalytic ozonation of humic acid/bovine serum albumin in water supply systems

In order to explore the interference mechanism of pipeline corrosions on ozonation of typical organic pollutants in water supply systems, the homogeneous catalytic ozonation experiments between Fe3+ and pollutants were carried out with simulated water containing metal ion Fe3+ and humic acid (HA) or bovine serum albumin (BSA). The results show that the ozonation efficiency of HA was higher than that of BSA. After ozonation for 60 minutes, the removal rates of two pollutants were 61.9% and 13.8% respectively. The existence of Fe3+ had different effects on ozonation of HA and BSA. The removal rate of the former decreased from 57.6% to 46.0% with the increase of Fe3+ dosage, and that of the latter increased from 12.4% to 40.0%. The two pollutant solutions’ Zeta potential in absolute value and average particle size decreased after ozonation with the coexistence of Fe3+. The average particle size of HA solution increased significantly after the addition of Fe3+, indicating obvious coagulation between HA and Fe3+. But the coagulation between BSA and Fe3+ was not obvious because there was only little change on the average particle size of the solution. The mechanism of ozonation of organic pollutants was also discussed, which stressed that the coagulation between HA and Fe3+ would offset the catalytic effect by Fe3+. It was inferred that the metal ion Fe3+ produced by pipeline corrosion could play some positive roles in secondary pollution control at the water supply network teminal, which involves enhanced degradation of protein pollutants in catalytic ozonation and synergistical removal of humic pollutants in coagulated form through filtration.