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以CuO-Ce0.5Mn0.5O2粉体为原料,采用挤条成型法制备了相应的成型载体,考察了成型过程中不同胶溶剂及其用量、焙烧时间及焙烧温度对该成型载体性能的影响,并对成型载体进行了抗压强度测试,且通过BET、SEM等手段对载体结构进行了表征,同时对相应的载钯催化剂进行了活性评价。结果表明,胶溶剂的添加可以不同程度地提高载体的抗压强度,改善载体的孔径分布,其中,柠檬酸作为胶溶剂时载体的抗压强度最大;使用硝酸作为胶溶剂时载体孔径分布向中孔方向集中;不同胶溶剂对载体的比表面积影响不大。固定硝酸质量分数3%,m(柠檬酸)∶m(胶粘剂)=4∶6,在600℃焙烧5 h可得到抗压强度98.65 N/cm2、比表面积为36.938 m2/g、孔容0.177 cm3/g的载体,对应载Pd(占载体质量的0.5%)催化剂的催化活性较高,在反应总压5 MPa,p(CO)∶p(O2)=94∶6、反应时间4 h、反应温度65℃的条件下,DPC收率9.91%。
CuO-Ce0.5Mn0.5O2 powder as raw material, extrusion molding method was used to prepare the corresponding shaped support, the effects of different peptizers and their dosage, calcination time and calcination temperature on the performance of the formed support were investigated. The compressive strength of the formed carrier was tested. The structure of the carrier was characterized by BET and SEM. Meanwhile, the activity of the supported palladium catalyst was also evaluated. The results show that the addition of peptizer can improve the compressive strength of carrier to some extent and improve the pore size distribution of carrier, in which the compressive strength of carrier is the highest when citric acid is used as peptizer; Hole direction; different peptizers have little effect on the specific surface area of the carrier. When the mass fraction of nitric acid is 3%, m (citric acid): m (binder) = 4: 6, the compressive strength 98.65 N / cm2 and specific surface area 36.938 m2 / g and the pore volume 0.177 cm3 / g, the catalytic activity of the supported Pd (0.5% of the carrier) is high. Under the conditions of reaction pressure 5 MPa, p (CO): p (O2) = 94: 6 and reaction time 4 h, Under the condition of temperature 65 ℃, the yield of DPC was 9.91%.