Wang Ching-Huei
Department of Chemical Engineering, Kao Yuan Institute of Technology, Kaohsiung 821, Taiwan, ROC.
Chemosphere. 2004 Apr;55(1):11-7. doi: 10.1016/j.chemosphere.2003.10.036.
The catalytic incineration of toluene over gamma-Al2O3-supported transition-metal oxide catalysts in the temperature range of 200-380 degrees C was investigated employing a fixed bed flow reactor. CuO/gamma-Al2O3 was found to be the most active of seven catalysts tested. Using this catalyst with different wt% Cu in the incineration of toluene, we found that the optimal Cu content was 5 wt%. X-ray diffraction, BET surface area and hydrogen-temperature-programmed reduction showed that it was mainly the formation of large CuO crystals that caused declines in catalyst activity at Cu content above 5 wt%. Addition of water vapor or CO2 inhibited catalyst activity, but this effect was reversible. Although coexistence of toluene and n-hexane resulted in a reduction in n-hexane conversion, the impact on toluene oxidation was only negligible. Temperature-programmed desorption revealed that this differential effect was due to more competitive adsorption of toluene onto active sites of the catalyst.
采用固定床流动反应器，研究了在200 - 380℃温度范围内，γ-Al2O3负载的过渡金属氧化物催化剂上甲苯的催化焚烧。在测试的七种催化剂中，CuO/γ-Al2O3被发现是活性最高的。在甲苯焚烧中使用不同铜含量（重量百分比）的该催化剂时，我们发现最佳铜含量为5 wt%。X射线衍射、BET表面积和氢程序升温还原表明，主要是大尺寸CuO晶体的形成导致铜含量高于5 wt%时催化剂活性下降。添加水蒸气或二氧化碳会抑制催化剂活性，但这种影响是可逆的。尽管甲苯和正己烷共存导致正己烷转化率降低，但对甲苯氧化的影响微不足道。程序升温脱附表明，这种差异效应是由于甲苯在催化剂活性位点上的竞争性吸附更强。
