Zuma Favourite, Lin Johnson, Jonnalagadda Sreekanth B
School of Chemistry, University of KwaZulu-Natal, Chiltern Hills, Durban, South Africa.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2009 Jan;44(1):48-56. doi: 10.1080/10934520802515335.
The effect of ozonation on the rate of disinfection of Escherichia coli was investigated as a function of ozone concentration, ozonation duration and flow rates. Ozone was generated in situ using Corona discharge method using compressed oxygen stream and depending on the oxygen flux the ozone concentrations ranged from 0.91-4.72 mg/L. The rate of disinfection of all the three microbes followed pseudo-first-order kinetics with respect to the microbe count and first order with respect to ozone concentration. The influence of pH and temperature the aqueous systems on the rate of ozone initiated disinfection of the microbe was investigated. The inactivation was faster at lower pH than at basic pH. Molecular ozone is found more effective in disinfection than hydroxyl radicals. Two reported mechanisms for antimicrobial activity of ozone in water systems from the literature are discussed. Based on the experimental findings a probable rate law and mechanism are proposed. Ozonation of natural waters significantly decreased the BOD levels of the control and microbe contaminated waters.
研究了臭氧化对大肠杆菌消毒速率的影响，该影响是臭氧浓度、臭氧化持续时间和流速的函数。使用压缩氧气流通过电晕放电法原位产生臭氧，根据氧气通量，臭氧浓度范围为0.91 - 4.72 mg/L。所有三种微生物的消毒速率相对于微生物数量遵循准一级动力学，相对于臭氧浓度遵循一级动力学。研究了水体系的pH值和温度对臭氧引发的微生物消毒速率的影响。在较低pH值下的失活比在碱性pH值下更快。发现分子态臭氧在消毒方面比羟基自由基更有效。讨论了文献中报道的水体系中臭氧抗菌活性的两种机制。基于实验结果，提出了可能的速率定律和机制。天然水的臭氧化显著降低了对照水和受微生物污染水的生化需氧量水平。
