-

Pentaerythritol (PE) is a tetravalent alcohol mainly used in painting (as alkyol resins) and military industries. PE is produced by reaction of acetaldehyde with fom1aldehyde in aqueous solution containing sodium hydroxide. The byproducts of the reaction are
dipentaerythritol, sodium formate and different linear and cyclic formals. Since the purpose of this work was the production of PE with high yield and high degree of
purity, at first the effect of operating parameters on the production yield was studied and the optimum operating ranges for reaction temperature, reaction time and molar ratio of reactants were determined. In the next step, considering that the applications of PE necessitate high degree of purity, different methods of purification such as crystallization, hydrolysis through refluxing hydrochloric acids, adsorption with activated carbon and separation based on solubility difference were investigated. The results indicated that separation based on solubility difference is the most appropriate method and whenever combined with crystallization, can increase the degree of purity of PE up to 99.4 percent