基于臭氧氧化对煤化工废水中苯系污染物去除的研究

苯、甲苯、乙苯、二甲苯(BTEX)是煤化工废水中的典型有机污染物，通常情况下较难被生物降解，实际生产过程中通常使用化学手段对其进行去除。本研究以臭氧氧化过程中产生的强氧化性自由基为基础，采用臭氧氧化技术对模拟废水中的BTEX进行去除实验。探究了pH值、温度、臭氧投加量以及臭氧投加模式对BTEX降解效果的影响；使用叔丁醇作为羟基自由基抑制剂、自由基歧化酶作为超氧自由基抑制剂，探究臭氧降解BTEX时的反应机理。实验结果表明:当pH值为8、反应温度为30 ℃、臭氧投加量为3.5 g/L、臭氧投加模式为逆流投加时，BTEX的降解效果最佳；羟基自由基和超氧自由基的存在是臭氧有效去除水中BTEX的根本原因。

Study on the removal of benzenes pollutants from coal chemical wastewater based on ozonation technology

Benzene, toluene, ethylbenzene and xylene(BTEX)are typical organic pollutants in coal chemical wastewater, which were difficult to be biodegraded under normal conditions, and were often removed by chemical means in the actual production process. This study based on the strong oxidizing free radicals generated in the process of ozone oxidation, used ozone oxidation technology to remove BTEX in simulated wastewater. The effects of pH value, temperature, ozone dosage and ozone dosing mode on the degradation of BTEX were investigated. The reaction mechanism of degradation by ozone was explored by using tertiary butanol as hydroxyl radical inhibitor and free radical dismutase as superoxide radical inhibitor. The results showed that the degradation effect of BTEX was the best when pH was 8, reaction temperature was 30 ℃, ozone dosage was 3.5 g/L and ozone dosage mode was countercurrent. The existence of superoxide radicals and hydroxyl radicals were the fundamental reason for the effective removal of BTEX from water by ozonization.