Use of Ion-Exchange Resins in Dehydration Reactions

Abstract

This chapter reviews the main uses of ion-exchange resins as catalysts for dehydration processes. In this regard, the dehydration of alcohols to alkenes is dealt with, and mainly to ethers, since these latter processes require a lower reaction temperature. Moreover, the large variety of ethers (linear, branched, cyclic), which can be synthesized in the presence of ion-exchange resins, has attracted the interest of many research groups, and important industrial applications have been envisaged. Another group of hydroxylated compounds, that is, bearing OH groups susceptible to be dehydrated, are carbohydrates. Monosaccharides such as glucose, fructose and xylose, mainly present in the lignocellulosic biomass, can be transformed, in the presence of ion-exchange resins, into platform molecules. Among them, furfural and 5-hydroxymethylfurfural possess a great potential as they can be utilized as building blocks for the production of high value-added chemicals and materials. The main catalytic processes will be described, providing detailed information about the catalytic performance, and underlining advantages and drawbacks of ion-exchange resins for each catalytic process.