甲醇氧化制甲醛中铁钼催化剂的改性研究

Study on Transformed Iron-molybdenum Catalyst for Partial Oxidation of Methanol to Formaldehyde

研究了添加不同含量的 La和 V及焙烧温度对铁钼系催化剂性能的影响。采用比表面积及孔径测定方法、TPD技术研究了焙烧温度对催化剂宏观结构和表面酸性的影响。结果表明 :随着焙烧温度的升高 ,催化剂的比表面积、孔容和催化活性均下降 ;催化剂的表面酸量与活性、选择性存在一定关系。当焙烧温度一定时 ,甲醛的收率随反应温度的升高大多表现出先升后降的规律。

Iron molybdenum catalyst in which lanthanum and vanadium were separately used as the third component was used in the selective oxidation of methanol to formaldehyde. According to the results obtained by BET method the specific surface area and the pore volume of ca talyst decrease with the increase in roasting temperature. The results obtained by TPD analysis established a direct relationship between the roasting temperature and the acid sites of the catalyst. The surface acidity of iron molybdenum vanadium decreases with the increase in vanadium quantity. The surface acidity of iron molybdenum lanthanum increases with the increase in lanthanum quantity. It was found what, when the reaction temperature increases the yield of formaldehyde increases and after reaches the maximum value then it decreases.