采用共沉淀耦合机械混合法制备了Cu/ZnO/Al2O3/Cr2O3+ H-ZSM-5双功能催化剂,并用于二甲醚水蒸气重整制氢反应,结合热重、傅里叶红外光谱、XRD、BET、H2-TPR表征,考察了焙烧温度对Cu/ZnO/Al2O3/Cr2O3催化剂物理化学性质及双功能催化剂催化性能的影响.研究结果表明,400℃焙烧时,析出CuO粒子的同时伴有尖晶石相,进而在反应过程中对金属铜粒子起到良好的隔离作用.而焙烧温度较低时,催化剂分解不完全,催化剂活性位较少.焙烧温度大于500℃时,CuO粒子发生二次团聚,同时尖晶石相大量生成,造成催化剂活性位减少,活性较低.合适的焙烧温度为400℃,此时二甲醚转化率为92.9％,氢气收率可达到76.5％,具有较好的反应效果.%The Cu/ZnO/Al2O3/Cr2O3+H-ZSM-5 performances for hydrogen production during dimethyl ether steam reforming (DME SR) were investigated, which was prepared by the co-precipitation coupling with mechanical mixing method. Meanwhile, the effect of calcination temperature on the physicochemical properties of catalysts were studied by thermogravimetry, Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer-Emmett-Teller, and H2 temperature-programmed reduction. It was revealed that Cu/ZnO/Al2O3/Gr2O3 catalyst was decomposed at 400℃ to form CuO and sponel phase that played a key role in separating the Cu during the reaction. Under lower calcination temperatures,the catalyst was incompeletely decomposed. Increasing the calcination temperature to over 500℃ caused severe sintering of CuO and facilitated the formation of spinel phase, which led to a significant decrease in the number of active sites. When the calcination temperature was controlled at 400℃, the biggest DME conversion rate of 92. 9% and hydrogen yield of 76. 5% was reached.
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