Sreethawong Thammanoon, Chavadej Sumaeth
The Petroleum and Petrochemical College, Chulalongkorn University, Soi Chula 12, Phyathai Road, Pathumwan, Bangkok 10330, Thailand.
J Hazard Mater. 2008 Jul 15;155(3):486-93. doi: 10.1016/j.jhazmat.2007.11.091. Epub 2007 Nov 29.
Ozone is a strong oxidant, which can oxidize both biodegradable and non-biodegradable organics. The main objective of this study was to use iron oxide as a heterogeneous catalyst to enhance the ozone oxidation process. The wastewater used in this study was distillery wastewater, which was diluted 20 times before use. The diluted distillery wastewater was fed continuously in a downflow direction in an ozonation column. The iron oxide catalyst was coated on 10.3mm diameter alumina balls (5.5 m2/g specific surface area) by using Fe(NO3)3 as a precursor. The prepared catalyst was in the form of ferric oxide, and its loading was 0.07%. From the experimental results of both with and without the iron oxide catalyst, an increase in hydraulic retention time resulted in an increase in the treatment efficiencies of both chemical oxygen demand (COD) and color reduction, since the residence time of ozone increased. When the ozone mass flow rate increased, both COD and color reduction increased, resulting from an increase in the hydroxyl radical available in the system. The ozonation system with the iron oxide catalyst gave the highest efficiency in both COD and color removals because the hydroxyl free radical generated from the catalyst is more reactive than the ozone molecule itself.
臭氧是一种强氧化剂，它既能氧化可生物降解的有机物，也能氧化不可生物降解的有机物。本研究的主要目的是使用氧化铁作为非均相催化剂来强化臭氧氧化过程。本研究中使用的废水是酿酒厂废水，使用前将其稀释了20倍。稀释后的酿酒厂废水在臭氧氧化柱中以向下流动的方向连续进料。以Fe(NO₃)₃为前驱体，将氧化铁催化剂负载在直径为10.3mm的氧化铝球（比表面积为5.5 m²/g）上。制备的催化剂为氧化铁形式，其负载量为0.07%。从有无氧化铁催化剂的实验结果来看，由于臭氧停留时间增加，水力停留时间的延长导致化学需氧量（COD）处理效率和脱色率均有所提高。当臭氧质量流量增加时，由于系统中可用羟基自由基的增加，COD和脱色率均增加。带有氧化铁催化剂的臭氧氧化系统在COD和脱色方面效率最高，因为催化剂产生的羟基自由基比臭氧分子本身更具反应性。
