ROLE OF SURFACE-ACIDITY OF BORON PHOSPHATE IN THE ACTIVITY AND SELECTIVITY OF THE DEHYDRATION OF ALCOHOLS

A comparison between the activity and selectivities of dehydration of 2-butanol, 2-methyl-2-butanol, and 3-methyl-2-butanol has been made with the surface acidity of boron phosphate catalysts of compositions ranging from P B = 0.4 to 1.4. The activity and the product distribution of the dehydration reactions of these alcohols were found to be sensitive to the change in the surface acid properties of the boron phosphate catalysts. The concentrations of trans-2-butene and 2-methyl-2-butene increase with increasing surface acidity, while those of the various remaining products show an inverse relationship to the acidity. The results are interpreted through a dominant carbonium ion mechanism with the possibility of an additional subsidiary process. © 1979.