A process is described for removing polar compounds from an aromatic feedstock which contains polar compounds and which is then used in an alkylation process. The process comprises contacting the feedstock in an adsorption zone at a temperature of less than or equal to 130° C. with an adsorbent selective for the adsorption of said polar compounds and comprising a molecular sieve having pores and/or surface cavities with cross-sectional dimensions greater than 5.6 Angstroms. A treated feedstock substantially free of said polar compounds is withdrawn from the adsorption zone and fed to an alkylation zone for contact under liquid phase alkylation conditions with an alkylating agent in the presence of an alkylation catalyst.