ABSTRACT
Two-component CuO-Ru based on active Al2O3 (CuO-Ru/Al2O3) catalyst was prepared by incipient wetness impregnation and used to catalytic ozonation of acetophenone (AP). The results showed that doping Ru could significantly improve the catalytic activity of CuO/Al2O3. For example, the COD removal rates of AP solution after 30 min by ozonation alone, CuO/Al2O3/O3, and CuO-Ru/Al2O3/O3 were 6.3%, 20.0% and 54.0%, respectively. The change of pH almost had no affect on degradation efficiency of AP. However, a comparison of COD removal between ozonation alone and catalytic ozonation indicated that CuO-Ru/Al2O3 catalyst was more suitable for application in neutral or acidic condition. CuO-Ru/Al2O3 catalyst could accelerate decomposition rate of ozone in water, and its decomposition rate constant reached 2.58 x 10(-3) s(-1) while that of ozone alone in double-water was 1.19 x 10(-3) s(-1). The experimental result of t-butanol indicated that CuO-Ru/Al2O3 catalytic ozonation of AP followed a radical-type mechanism.
Subject(s)
Acetophenones/chemistry , Aluminum Oxide/chemistry , Copper/chemistry , Ozone/chemistry , Water Pollutants, Chemical/metabolism , Acetophenones/isolation & purification , Catalysis , Ruthenium/chemistry , Waste Disposal, Fluid/methodsABSTRACT
The effect of ozonation of terephthalic acid (TA) was evaluated, and the kinetic and mechanism of this process were also discussed. The rate constants of TA with ozone and OH radicals calculated by the relative method are (0.047 +/- 0.010) L x (mol x s)(-1) and 2.28 x 10(9) L x (mol x s)(-1), respectively. The above result was in accordance with the apparent reaction rate constant of ozonation of TA when the process was controlled by chemical reaction. Intermediates detected by high-performance liquid chromatography (HPLC) and ion chromatography (IC) included benzoic acid, tartaric acid, formic acid and oxalic acid, therefore the possible destruction pathway of ozonation of TA was proposed on the basis of above results.
