Mn/MgO催化剂上乙腈和甲醇选择性合成丙烯腈的研究

采用浸渍法制备了Mn/MgO催化剂,考察了催化剂的活性组分含量及反应温度等因素对乙腈和甲醇选择性合成丙烯腈的影响,并对催化剂进行了XRD和CO2-TPD表征。结果表明,随着Mn的加入,催化剂的性能有很大提高,当m(Mn)∶m(MgO)=5∶100时,乙腈转化率达到最高;420℃反应时,催化剂具有较好的反应性能,乙腈转化率为40 5%,丙烯腈选择性达86 3%。CO2-TPD研究发现,Mn/MgO催化剂表面强碱中心数目越多,越有利于乙腈和甲醇选择性合成丙烯腈反应。

Study of Mn/MgO Catalysts for Acrylonitrile Synthesis from Acetonitrile and Methanol

A series of Mn/MgO catalysts were prepared by impregnation method and characterized by XRD and CO_2-TPD. Selective synthesis of acrylonitrile from acetonitrile and methanol was carried out in a conventional flow reactor system.The effects of Mn loading and reaction temperature on the catalytic properties of Mn/MgO were studied.Experimental results show that the catalytic properties is greatly improved by the addition of Mn to MgO.At Mn loading m(Mn)∶m(MgO)=5∶100,it has the best catalytic property with 40.5% conversion of acetonitrile and 86.3% selectivity for acrylonitrile at 420 ℃.CO_2-TPD shows that the more the strong base sites on the surface of the catalyst,the more favorable for the reaction.