Cu/Zn/Al/Mn催化剂上CO/CO2加氢合成甲醇特性研究

利用共沉淀法制备了四组分的Cu-Zn-Al-Mn和Cu-Zn-Al-Ce催化剂以及三组分的Cu-Zn-Al催化剂。利用组成H2/CO/CO2/N2=66/27/3/4(体积比)的富CO原料气对催化剂进行了活性评价，并研究了温度、压力和空速等反应条件对催化剂活性的影响。结果发现添加适量的锰助剂能显著提高催化剂的活性和热稳定性。利用SEM和XRD方法进行了催化剂的结构和形貌表征，同样表明锰助剂可以起到阻止CuO晶粒长大和促进CuO分散作用。利用富CO2的生物质原料气体积比为H2/CO/CO2/N2=50/25/20/5对Cu-Zn-Al-Mn催化剂进行的评价表明：Cu-Zn-Al-Mn催化剂上CO/CO2加氢合成甲醇的甲醇产率和选择性均有下降，在试验范围内，甲醇产率下降11％～25％，选择性为93％～95％。

Methanol synthesis from CO/CO2 hydrogenation over Cu/Zn/Al/Mn catalyst

Cu-Zn-Al-Mn, Cu-Zn-Al-Ce and Cu-Zn-Al catalysts were prepared by coprecipitation method. Their activities were evaluated using a feed gas composed of H2(66%),CO(27%),CO2(3%) and N2(4%). The results indicated that Mn was an effective promoter to improve the activity and thermal stability of Cu-Zn-Al catalyst. The study of catalyst characterization using XRD (X-ray Diffraction) and SEM (Scanning Electron Microscopy) also showed that Mn promoter was favorable for the dispersion of CuO. The activity of Cu-Zn-Al-Mn catalyst was further evaluated using a CO2-rich feed gas composed of H2(50%),CO(25%),CO2(20%) and N2(5%). The results indicated that both STY (space time yield) and selectivity of methanol were decreased when CO2-rich syngas was used. Under tested ranges, the STY was decreased 11%～25% and the selectivity was 93% to 95%, decreasing in the range of 3.5%～5.7%.