碱性助剂K对CuZrO_(2)催化剂上乙醇缩合制2-戊酮反应性能的影响

Effect of basic promoter K on reaction performance of ethanol condensation to 2-pentanone over CuZrO_(2) catalyst

为了提升乙醇转化制2-戊酮催化剂的活性,采用碱性助剂K对CuZrO_(2)催化剂进行了改性,考察了K含量对催化剂催化乙醇缩合反应性能的影响,并结合不同的表征手段对催化剂的结构和表面酸碱性等进行了分析。结果表明,随着K含量的增加,催化剂的比表面积和表面Cu含量逐渐降低,此时,由于K的引入阻碍了CuO的还原,抑制了乙醇脱氢形成乙醛过程,导致乙醇转化率也逐渐减低。K的引入明显促进了酮类产物的形成,且在K质量分数为2.2%时,总酮选择性达到72.9%,其中2-戊酮选择性为36.0%。K提高了催化剂表面中强碱性位的碱性,对缩合反应有利。

In order to improve the activity of the catalyst for the conversion of ethanol to 2-pentanone,the CuZrO_(2) catalyst was modified with the basic promoter K.The effect of the content of K on the catalytic performance for ethanol condensation was investigated.Combined with different characterization methods,the structure,surface acidity and alkalinity of the catalyst were analyzed.The results show that the specific surface area and surface Cu content of the catalyst gradually decrease with the increase of the content of K.At the same time,the introduction of K impedes the reduction of CuO and inhibits the ethanol dehydrogenation to acetaldehyde,leading to the gradual decrease of ethanol conversion.The introduction of K obviously promotes the formation of ketone products,and the total ketone selectivity reaches 72.9%when the mass fraction of K is 2.2%,of which the selectivity of 2-pentanone is 36.0%.K improves the basicity of the strongly basic sites in the catalyst surface,which is favorable for the condensation reaction.