School of Chemical Engineering, Universiti Sains Malaysia, Nibong Tebal, 14300 Penang, Malaysia.
J Hazard Mater. 2010 Jan 15;173(1-3):159-67. doi: 10.1016/j.jhazmat.2009.08.060. Epub 2009 Aug 22.
The ambient sonocatalytic degradation of congo red, methyl orange, and methylene blue by titanium dioxide (TiO(2)) catalyst at initial concentrations between 10 and 50mg/L, catalyst loadings between 1.0 and 3.0mg/L and hydrogen peroxide (H(2)O(2)) concentrations up to 600 mg/L is reported. A 20 kHz ultrasonic processor at 50 W was used to accelerate the reaction. The catalysts were exposed to heat treatments between 400 and 1000 degrees C for up to 4h to induce phase change. Sonocatalysts with small amount of rutile phase showed better sonocatalytic activity but excessive rutile phase should be avoided. TiO(2) heated to 800 degrees C for 2h showed the highest sonocatalytic activity and the degradation of dyes was influenced by their chemical structures, chemical phases and characteristics of the catalysts. Congo red exhibited the highest degradation rate, attributed to multiple labile azo bonds to cause highest reactivity with the free radicals generated. An initial concentration of 10mg/L, 1.5 g/L of catalyst loading and 450 ppm of H(2)O(2) gave the best congo red removal efficiency of above 80% in 180 min. Rate coefficients for the sonocatalytic process was successfully established and the reused catalyst showed an activity drop by merely 10%.
研究了在初始浓度为 10-50mg/L、催化剂负载量为 1.0-3.0mg/L 和过氧化氢（H(2)O(2)）浓度高达 600mg/L 的条件下，二氧化钛（TiO(2)）催化剂对刚果红、甲基橙和亚甲基蓝的环境超声催化降解。采用 20kHz、50W 的超声波处理器来加速反应。将催化剂在 400-1000℃下进行热处理，时间长达 4h，以诱导相变。少量金红石相的声催化剂表现出更好的超声催化活性，但应避免过多的金红石相。在 800℃下加热 2h 的 TiO(2)显示出最高的超声催化活性，染料的降解受到其化学结构、化学相和催化剂特性的影响。刚果红表现出最高的降解速率，这归因于多个不稳定的偶氮键导致与自由基产生的最高反应性。在 180min 内，初始浓度为 10mg/L、催化剂负载量为 1.5g/L 和 H(2)O(2)初始浓度为 450ppm 的条件下，刚果红的去除效率超过 80%。成功建立了超声催化过程的速率常数，并且重复使用的催化剂的活性仅下降了 10%。
