甲醛和丙醛缩合制备甲基丙烯醛反应动力学

通过气相色谱和傅里叶红外光谱仪分析，考察了不同仲胺化合物对甲醛和丙醛缩合制备甲基丙烯醛的催化性能. 结果表明，二乙胺催化效率最高，甲基丙烯醛的收率高达94%. 进一步研究了以二乙胺为催化剂缩合制备甲基丙烯醛的反应动力学规律，得出反应级数为2.456，反应活化能和指前因子分别为62.45 kJ/mol和8.182′107 (mol/L)-1.456/s. 并通过在线红外光谱仪和气质联用仪证实生成了中间体曼尼希碱，为进一步研究反应机理奠定了基础.

Reaction Kinetics for Preparation of Methacrolein by Condensation of Formaldehyde with Propionaldehyde

A series of second amines were used to catalyze the synthesis of methacrolein from formaldehyde and propionaldehyde via Mannich reactionBy using diethylamine,the highest yield of 94% was obtained.The kinetic model was obtained by analysis of the reaction process.The parameters in the model were determined:reaction order 2.456,activation energy 62.45 kJ/mol and frequency factor 8.182×107（mol/L）^-1.456/s.In situ FT-IR spectroscopy was introduced to monitor the concentration of compounds in real time during the reaction.The samples taken in different reaction times were analyzed by GC-MS,and the intermediate Mannich base was detected,laying a foundation for the reaction mechanism.