引言Cu/ZnO/Al2O3催化剂近年来广泛应用于低压甲醇合成、二甲醚合成和水煤气变换等领域[1-2],该催化体系具有活性高、使用寿命长、反应温度及压力较低等优点[3].目前工业上主要采用共沉淀法制备Cu/ZnO/Al2O3催化剂[4-6],共沉淀法所制备的Cu/ZnO/Al2O3催化剂虽然具有较好的催化活性,但它有如下缺点:①沉淀法过程较为复杂,包括沉淀、老化、过滤、洗涤、干燥、焙烧等,每一步对催化剂的性能都有一定的影响,特别是沉淀、老化和焙烧;②需要精确控制溶液的pH值和温度;③催化剂含有少量的碱金属离子;④沉淀法制备Cu/ZnO/Al2O3的过程中会产生大量的工业废水,污染环境[7].为了解决这些问题,研究环境友好的高活性Cu/ZnO/Al2O3催化剂的制备方法将具有重要的意义.%Cu/ZnO/Al2O3 catalysts were prepared by mechanical milling and combustion at different calcination temperatures and were tested for the synthesis of methanol from CO hydrogenation. Calcination of catalyst precursors was monitored with thermogravimetry differential scanning calorimeter (TG-DSC). These catalysts were characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), N2 adsorption, temperature-programmed reduction with H2 (TPR) and N2O oxidation followed by H2 titration. The results showed that the physicochemical properties of the prepared catalysts depended strongly on calcination temperature, and BET surface area and dispersion of copper species decreased with increasing calcination temperature. The catalyst calcined at 350℃ exhibited the highest activity and stable catalytic performance. The method could be a promising alternative for the preparation of highly efficient Cu/ZnO/Al2O3 catalysts.
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