基于两种不同自由基的高级氧化法深度处理造纸废水的对比研究

Comparison of Sulfate Radical-advanced Oxidation Process (SR-AOP) and Fenton Oxidation for Advanced Treatment of Papermaking Wastewater

关键词:  造纸废水  深度处理  高级氧化  硫酸根自由基  羟基自由基  Fenton氧化  PS氧化

Key Words:advanced oxidation process  papermaking wastewater  advanced treatment  sulfate radical  hydroxyl radical  Fenton oxidation process  Sulfate radical-advanced oxidation process

摘要:采用亚铁离子(Fe^{2+,/sup>)活化过硫酸钠(PS)产生硫酸根自由基(SO-4·)和传统Fenton氧化法产生羟基自由基(·OH)氧化降解造纸废水中难降解的有机污染物,对比了两种高级氧化法的处理效果,考察了初始pH值、氧化剂用量、催化(活化)剂用量等对处理效果的影响及反应过程的规律。结果表明,与Fenton氧化体系相比，硫酸根自由基对pH值的适宜范围更广,在酸性至中性条件下,硫酸根自由基皆可有效降解有机污染物；在体系催化(活化)剂用量相同的条件下,两种自由基体系可以产生相当的处理效果,且Fe2+用量对PS氧化反应影响更小；两种氧化体系的COD_Cr降解率和色度去除率随氧化剂用量的增加而增加,达到适宜用量后Fenton氧化的COD_Cr降解率和色度去除率呈现下降趋势,而PS氧化的COD_Cr降解率和色度去除率趋于平缓；从氧化反应动力学可以看出,PS氧化反应相对缓慢些,且整个过程呈缓慢上升趋势,更利于氧化剂的完全利用。}

Abstract:Papermaking wastewater advanced treatments by Fenton oxidation or Sulfate radical-advanced oxidation process (SR-AOP) using the ferrous as the catalyst (activator) were compared, and the effect of pH on the degradation efficiency of the wastewater was investigated at room temperature, also the effects of Fe²⁺ dosage, PS dosage on the COD_Cr and color removal were studied. The results showed that, the COD_Cr degradation or color removal at SO-4· oxidation process was equivalent to ·OH oxidation process at pH=3, but higher than Fenton at pH＞3; Fenton oxidation process was even sensitive by the influence of Fe²⁺ dosage or oxidation dosage. Degradation kinetic was analyzed by Origin 8.5 drawing tool, and it indicated that, in the whole process, SR-AOP is reacted more gently than Fenton oxidation process, which indicates that the former is a promising alternative for the treatment of papermaking wastewater.