INFLUENCE OF THE PREPARATION PROCEDURE ON THE ACIDITY OF TITANIUM-DIOXIDE AND ITS CATALYTIC PROPERTIES IN THE REACTION OF SYNTHESIS OF BETA-PICOLINE BY CONDENSATION OF ACROLEIN WITH AMMONIA

It is shown that both strong Lewis acid sites that are capable of pola rizing benzene molecules and weaker ones responsible for the ionizatio n of p-xylene are formed on the surface of titanium dioxide synthesize d from sulfate-containing reactants. The concentrations of both types of centers are determined by the content of sulfate anions. Titanium d ioxide containing sulfate ions shows high activity and selectivity in the reaction of beta-picoline synthesis via condensation of acrolein w ith ammonia.