不同方法合成的镁铝水滑石的表征及其催化原油酯化脱酸性能

 分别采用双滴法、尿素法和超声波法合成镁铝水滑石 LDH-CP、LDH-UR 和 LDH-US，以 XRD、N₂吸附-脱附、TG-DSC 和 Hammett 碱强度-碱量表征它们的物化性质，以催化原油酯化脱酸反应评价它们的催化性能，并推测反应机理。结果表明，兼具高结晶度和高碱量的水滑石具有最佳的催化酯化活性，既能使醇生成强亲核性的 R₁O^-，又避免了导致副反应的游离 R₁O^-的产生。LDH-UR 结晶度最高，但碱量最低；LDH-US 碱量最高，但结晶度最低；LDH-CP兼具高结晶度和高碱量，有最高的脱酸活性，可将绥中原油酸值从3.72 mgKOH/g 降到0.40 mgKOH/g 以下。

Characterization of MgAl Hydrotalcites Prepared by Various Methods and Their Catalytic Activities for Esterification to Remove Acid From Crude Oil

Three carbonate hydrotalcites(LDH) with same molar ratio of Mg and Al were prepared by constant pH,urea and ultrasonic coprecipitation methods,respectively,and named as LDH-CP,LDH-UR,LDH-US.Their properties were characterized by XRD,N2 adsorption-desorption and thermal analysis.The basicity strength and basic sites amount of the three hydrotalcites were measured by Hammett indicator-benzene carboxylic acid titration,and furthermore,their catalytic activity in the esterification reaction of petroleum acid an...