Catalysts based on clay of the smectite type, process for obtaining them and their application to the acylation of aromatic hydrocarbons

摘要

These catalysts are characterised in that they exhibit at least the following properties: a basal distance determined in air and at room temperature of at least 10 ANGSTROM and compensating cations or exchangeable cations in which at least 10 meq/100 g of dry clay are cations of the type of those belonging to the class of hard acids, according to the classification established by R.G. Pearson (Journal of the American Chemical Society, 85, 22, 1963, p. 3533, 3539).