【摘要】 采用水溶液法制备Mo-V-Te-Nb-O催化剂,通过XRD和BET对催化剂进行表征,考察连续固定床微型反应研究制备过程中干燥方式、干燥温度及煅烧方式对催化剂结构和性能的影响。结果表明,减压下旋转蒸发与常压下加热蒸发的干燥方式相比,前者利于生成活性组分分布均匀的催化剂前驱体,且催化剂晶相结构中有利于提高活性和选择性的M1相、M2相比例较大,催化剂比表面积比后者增加了31.5%,适宜的干燥温度为50℃,N2,He气氛在催化剂煅烧过程中均起到防止空气氧化的作用,对催化剂的结构和性能影响相同,空气中275℃下预煅烧60 min制备的催化剂晶相结构中Te含量增加,该催化剂比表面积为2.78 m2/g,在反应温度为360℃时表现出良好的催化性能,丙烷的转化率为47.6%,丙烯酸的选择性为50.5%。更多还原

【Abstract】 Mo-V-Te-Nb-O catalysts were prepared by aqueous solution.Effects of dryness and calcinations modes in catalyst preparation on the catalyst structure and performance were studied by XRD,BET and continuous fixed-bed microreactor.Compared to the catalyst prepared by dry under ordinary pressure method,the catalyst by rotary evaporation under the decompression was more favorable.The catalyst precursor for even distribution in the active component can be generated easier.The proportion of M1 and M2 phase in the catalyst structure which were conducive to improve the activity and selectivity in catalyst were larger.The catalyst surface area was also increased by 31.5%.The suitable rotating evaporating temperature was 50 ℃;the effects of N2 and He in calcinations to the structure and properties of catalysts were the same to prevent air oxidation.The Te content in the catalyst which was pre-calcination 60 min in air at 275 ℃ was increased,and the catalyst surface area was 2.78 m2/g.The C3H8 conversion was 47.6% and the acrylic acid selectivity was 50.5% when the reaction temperature was 360 ℃.更多还原