以活性氧化铝颗粒(GAA)、13X分子筛(13XMS)和4A分子筛(4AMS)为载体,通过共浸渍法制备3种CuO-CeO2负载型催化剂,利用氮吸附-脱附、扫描电镜、X射线衍射等手段对催化剂进行表征,并在固定床催化反应装置上评价萘的催化活性。结果表明,载体对CuO-CeO2催化剂的性能影响很大,CuO-CeO2/4AMS对萘的催化能力较差,而CuOCeO2/GAA和CuO-CeO2/13XMS则具有良好的萘催化能力;随着催化反应温度升高,CuO-CeO2/GAA和CuO-CeO2/13XMS的催化能力显著提升,350℃时2种催化剂对萘的CO2产率分别为85%和81%,去除率均超过98%,CuO-CeO2/13XMS具有比CuO-CeO2/GAA更好的低温活性,250℃时CO2产率接近70%;CuO-CeO2/13XMS和CuO-CeO2/GAA经过5次循环实验后去除率均保持在92%以上,反应稳定性较好。
Three kinds of CuO-CeO2 catalysts supported on granular activated alumina (GAA), 13X molecular sieve (13XMS) and 4A molecular sieve (4AMS) were prepared by the co-impregnation method. The physical and chemical properties of the catalysts were characterized by N2 adsorption-desorption and scanning electron microscopy as well as X-ray diffraction, and their catalytic activities of naphthalene (Nap) oxidation were evaluated using a fixed-bed reactor. The results indicate that the carriers have strong influences on the catalytic activities of the CuO-CeO2 catalysts for Nap. CuO-CeO2/4AMS catalyst shows a poor catalytic activity for Nap. Whereas CuO-CeO2/GAA and CuO-CeO2/ 13XMS exhibit a higher catalytic activity, and they are both significantly improved at elevating reaction temperatures. The CO2 yields of Nap over CuO-CeO2/GAA and CuO-CeO2/ 13XMS 85% and 81% separately, and their removal efficiencies are both exceed 98% at 350 ℃. Moreover, CuO- CeO2/13XMS shows a better catalytic activity for Nap than CuO-CeO2/GAA at low temperature, whose CO2 yield is up to 70% at 250 ℃. In addition, CuO-CeO2/13XMS and CuO- CeO2/GAA still have excellent catalytic activities for Nap and their catalytic efficiencies are more than 92% after 5 cycles,which indicates that two catalysts both have a high reaction stability.