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考察了不同助剂(Mn、Zn、Co)对CuFeZr催化剂用于合成气制混合醇的影响。借助BET、XRD、H2-TPR等对其物化性质进行了表征,结果表明,加入助剂可减小颗粒粒径并且增强对CO的吸附能力以及催化剂表面碱性,其中,加入Zn可以增强CuFe间的相互作用,改善CuFeZr催化剂的还原性质,提高对CO的吸附能力,以及提供最强的表面碱性。用固定床反应器对催化剂的反应性能进行了评价,反应结果表明,加入Zn可以显著提高CuFeZr催化剂用于合成气制混合醇的反应活性及醇选择性,使醇时空收率从0.026 g/(gcat·h)提高至0.071 g/(gcat·h)。由于循环条件下,反应产物CO_2同时也是原料气的组成成分,进一步地探究了原料气中CO_2浓度对催化剂反应性能的影响。结果表明,加入CO_2可提高CO转化率和醇以及烃的收率,但阻碍链增长反应并使得产物烯烷比降低。其中,在所考察浓度范围内,原料气中含有2.5%的CO_2最有利于醇和烃的生成尤其是低碳醇和低碳烃的生成。
The effects of different additives (Mn, Zn, Co) on the mixed alcohols of CuFeZr catalyst for synthesis gas were investigated. The physico-chemical properties were characterized by means of BET, XRD and H2-TPR. The results showed that the addition of additives can reduce the particle size and enhance the adsorption capacity of CO and the alkalinity of the catalyst surface. Among them, Of the interaction, improve the reduction properties of CuFeZr catalyst, improve the adsorption capacity of CO, and provide the strongest surface alkalinity. The reaction performance of the catalyst was evaluated in a fixed-bed reactor. The results showed that the addition of Zn could significantly improve the reactivity and alcohol selectivity of CuFeZr catalyst for the synthesis of mixed alcohols. The yield of alcohol in space-time from 0.026 g / gcat · h) to 0.071 g / (gcat · h). Due to the cyclic condition, the reaction product CO_2 is also the component of the feed gas, and the effect of CO 2 concentration in the feed gas on the reaction performance of the catalyst is further explored. The results showed that addition of CO 2 increased the conversion of CO and the yield of alcohols and hydrocarbons, but hindered the chain growth reaction and decreased the alkane ratio of the product. Among them, 2.5% CO 2 in the feed gas is the most conducive to the formation of alcohols and hydrocarbons, especially the formation of lower alcohols and lower hydrocarbons within the investigated concentration range.