摘要
采用完全液相技术结合热解方法制备了固定床用CuZnAl催化剂,研究表明,该方法能保留完全液相技术赋予催化剂的特殊性能,可以发展成为将完全液相技术拓展于固定床催化剂的通用方法.在所制催化剂中引入碱助剂同样可以增加C_(2+)醇的选择性,但主要不是异丁醇,与现行常规方法制备的催化剂不同.通过对催化剂进行XRD、 H_2-TPR、 NH_3-TPD-MS、 BET等表征,结果表明,不同碱助剂对催化剂的作用方式和影响程度不同,使得催化剂中Cu物种的存在形式和数量、催化剂表面的酸碱性和量以及孔道结构存在差异,进而对催化剂性能产生影响.
CuZnAl catalysts for a fixed bed reactor were prepared by the complete liquid phase technology combined with pyrolysis method. The results showed that this method could retain the special properties of the catalysts entrusted by the complete liquid phase technology, and could be developed into a general method of extending the complete liquid phase technology to fixed bed catalyst preparation. The selectivity of C_(2+) alcohols can also be increased when introducing alkali promoters were added into the prepared catalysts, but C_(2+) alcohols was mainly not isobutanol, which was different from the catalysts prepared by conventional methods. XRD, H_2-TPR, NH_3-TPD-MS and BET measurement results showed that different alkali promoters had different action way and effects over the catalysts, which resulted in difference of active metals existing forms and amount, the catalyst surface acidic and basic strength and amount as well as pore structure, thus affecting the performance of the catalysts.
引文
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