臭氧催化氧化预处理甲缩醛生产废水试验研究

Experimental Study on Pretreatment of Methyl Acetal Production Wastewater by Catalytic Ozone Oxidation

摘要: 作为一种新兴的环境友好化学品，甲缩醛在绿色化学工艺中发挥着重要作用，甲缩醛生产过程产生的高浓度难生物降解有机废水的处理工艺目前鲜有报道。为探索臭氧催化氧化工艺对该废水的预处理效果，提高废水可生化性(B/C),为后续生化处理提供便利条件。采用浸渍法制备了以活性炭(AC)为载体的双金属复合催化剂Fe-Mn-AC，并与外购的2种催化剂进行了对比试验，对催化效果最优的催化剂进行表征分析微观结构，进行了工艺优化试验以确定最佳工艺参数。实验结果表明：催化剂选用Fe-Mn-AC、催化剂用量为25 g/L、废水初始pH值为8.3、反应温度为25℃、臭氧流量为1.5 L/min；臭氧浓度为102 mg/L条件下，废水COD的去除率达到74.32%，B/C比由初始的0.120提升到0.472，为后续生化处理创造了有利条件。

Abstract: Methylal is a new environmentally friendly chemical, which plays an important role in green chemical processes. A large amount of wastewater produced in the process of methal production and research and development belongs to high-concentration organic wastewater that is difficult to biodegrade. At present, there are few reports on the treatment technology of methyl acetal wastewater. In order to explore the efficiency of catalytic ozone oxidation process for pretreatment of methylal production wastewater and improve the biodegradability (B/C) of wastewater, and provide favorable conditions for subsequent biochemical treatment. Fe-Mn-AC ozone catalyst was prepared by impregnation method, and compared with two purchased catalysts, the microstructure of the catalyst with the best catalytic effect was characterized and analyzed, and then the process optimization test was carried out to determine the best process parameters. It was determined that Fe-Mn-AC was selected as catalyst, the amount of catalyst was 25 g/L, the initial pH of wastewater was 8.3, the reaction temperature was 25˚C, and ozone flow rate 1.5 L/min. When the ozone concentration is 102 mg/L, the removal rates of COD and UV254 in wastewater reach 74.32% and 66.84%, respectively, and the B/C ratio increases from the original 0.120 to 0.472, indicating better biodegradability.