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结合行星式球磨机,采用机械化学法制备Ni-Al2 O3催化剂,考察了焙烧温度和焙烧时间对Ni-Al2 O3催化剂晶相结构、还原特征、孔道结构和浆态床CO甲烷化性能的影响.通过XRD、H2-TPR、BET、XPS和TPH等方法对反应前后催化剂进行表征.结果表明,焙烧温度从350℃升高到700℃,活性前体NiO仍在载体表面高度分散,催化剂还原峰温向高温方向偏移.其中,450℃条件下焙烧所获得的cat-450试样比表面积最大,为350 m2/g.评价结果显示,焙烧温度从350℃升高到700℃,CO转化率、CH4选择性和收率均呈先升高后降低的趋势,于450℃达到最大值,分别为97.8％、88.2％和86.2％.另外,焙烧时间对催化剂的还原性能影响较小,对载体Al2 O3的晶相结构有一定影响.随焙烧时间延长,CO转化率稍有降低,而后增大;焙烧时间为4 h,CH4选择性和收率均较大.“,”Effects of calcination temperature and calcination time on the crystal structure, reduction characteristics, pore structure and CO methanation performance of Ni-Al2 O3 catalyst were investigated by using a mechanical-chemical method to prepare Ni-Al2 O3 catalyst. The catalysts were characterized by XRD, H2-TPR, BET, XPS and TPH. The results showed that the calcination temperature increased from 350℃ to 700℃, NiO was still well dispersed on the surface of the carrier, and the reduction peak temperature decreased to high temperature. The specific surface area of the cat-450 sample obtained by calcination at 450 ℃ was 350 m2/g. The results showed that with the calcination temperature increased from 350℃ to 700℃, CO conversion, CH4 selectivity and yield were increased first and then decreased, reaching the maximum at 450 ℃, with 97. 8％, 88. 2％ and 86. 2％, respectively. In addition, the calcination time has little effect on the reduction performance of the catalyst, and has small influence on the crystal structure of the carrier Al2 O3 . With the increase of calcination time, CO conversion decreased slightly and then increased with the better calcination time of 4 h.