浆态床反应器中生物质合成气合成二甲醚的研究

DME synthesis from biomass-derived syngas in a slurry-bed reactor

摘要: 进行了浆态床反应器中,甲醇合成催化剂与分子筛混合制复合催化剂上,生物质制取的合成气(简称生物质合成气)一步法合成二甲醚的研究,重点考察了不同脱水组分和工艺条件对催化剂反应性能的影响,同时,结合NH₃-TPD等手段对催化剂进行了表征。结果表明,含有较弱酸性SAPO-11分子筛的复合催化剂更适合生物质合成气原料气杂质多、氢碳比低的特点,在合成二甲醚反应中具有更高的选择性和稳定性。250℃、5 MPa、500 h^-1时,在甲醇催化剂与SAPO-11分子筛比例为3:1的复合催化剂上,合成气合成二甲醚反应35 h内,CO转化率稳定在40%以上,二甲醚在有机产品中的选择性保持在97%左右。

Abstract: Dimethyl ether (DME) synthesis from biomass-derived syngas in a slurry-bed reactor was investigated over a hybrid catalyst composed of methanol synthesis catalyst and molecular sieve. The results showed that the catalyst containing SAPO-11 exhibits higher DME selectivity and catalytic stability, which is closely related to the weak acidity of SAPO-11 in the hybrid catalysts. 40% CO conversion and 95% DME selectivity in organic products could be kept during 35 h stability test over the hybrid catalyst when the weight ratio of methanol synthesis catalyst to SAPO-11 was 3.