摘要
在超临界水氧化过程中,氨作为含氮有机物氧化的中间产物,其氧化是有机物在超临界水中氧化降解速率的控制步骤。综述了氧化剂、温度、过氧量、停留时间和催化剂等因素对氨的超临界水氧化降解效果的影响,并总结了目前常用的两种反应动力学模型。与双氧水或氧相比,NO3-氧化剂具有更强的氧化能力;通过提高温度、过氧量和停留时间都可以促进氨的超临界水氧化降解。在氨的超临界水氧化中,当无催化剂作用时,氨的降解率很低;加入MnO2/CeO2等催化剂,可以显著提高氨的降解率。为加快超临界水氧化法处理含氮有机废水的应用进程,未来应侧重氨氧化机制的研究和催化剂的开发。
In oxidation process of supercritical water,ammonia is identified as an intermediate of nitrogen contai- ning organics. Oxidation is the control of reaction rate. The influence of oxidant, temperature, excess oxygen and residence time was investigated in this paper. Also the latest research on the development of catalysts and kinetic models were also reviewed. The study found a comparison between H202 or 02, using NO3^- as an oxidant can get higher conversion of NH3. Although increasing temperature, excess oxygen and residence time could accelerate the oxidative degradation of NH3, their effects were less significant than catalysts. By adding the MnO2/CeO2 catalysts, the conversion of NH~ can be much higher. Based on the progress of ammonia oxidation in SCW at the moment,more research work should be done on catalysts＇ development and also ammonia oxidation mechanisms should be investigated.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2008年第9期81-84,92,共5页
Environmental Pollution & Control
基金
国家高技术研究发展计划资助项目(No.2006AA06Z313)
国家重点基础研究发展计划资助项目(No.2003CB214500)
关键词
超临界水氧化
氨
催化剂
supercritical water oxidation
NH3
catalysts
