Na2O或K2O对气相合成1–苯基氮杂环庚烷的CoO/SiO2-Al2O3催化剂的作用

研究了Na2O或K2O对苯胺和1,6己二醇气相合成1-苯基氮杂环庚烷的CoO/SiO2-Al2O3催化剂的作用,并采用X射线衍射、透射电子显微镜、H2-程序升温还原、NH3-程序升温脱附等技术对催化剂进行了表征.结果表明,Na2O助剂能增加催化剂的弱酸中心数,减少中强酸中心数,使催化剂的选择性得到提高.加入K2O使催化剂的弱酸中心数显著减少,并使CoO在反应过程中易于烧结,因此不利于1–苯基氮杂环庚烷的合成.

Effect of Na2O or K2O on CoO/SiO2-Al2O3 Catalyst for the Vapor-Phase Synthesis of 1-Phenylazepane

The CoO/SiO2-Al2O3 doped with Na2O or K2O for the vapor-phase synthesis of 1-phenylazepane from aniline and 1,6-hexanediol was studied. The catalysts were characterized by XRD, TEM, H2-TPR and NH3-TPD. The results indicated that Na2O not only increased the amount of weak acid sites of the catalyst, but also decreased the amount of the middle-strong acid sites, as a result, Na2O improved the selectivity of the catalyst. The addition of K2O took disadvantage of the synthesis of 1-phenylazepane for the amount of weak acid sites decreased remarkably and the CoO particles were sintered easily during the reaction.