Synthesis Of Neopentyl Glycol

Neopentyl glycol has been widely used as plasticizer for producing polyester and polyurethane foamed plastic, additive for advanced lubricant, alkyd resin, refractory material, insecticide, weedicide, initiator, extracting agent and separating medium for the separation of arene and cyclanes. The derivatives of neopentyl glycol are applied extensively in automobile, spin, medicament, painting, plastic and petroleum field. With the national new apparatus for producing neopentyl glycol putting into production and deep development, the applying field will expanded largely.Neopentyl glycol is a glycol, which was synthesized from formaldehyde and isobutyl aldehyde. The mechanism is as follows: firstly, formaldehyde and isobutyl aldehyde reacted into pentaldol by aldol condensation, and then formed neopentyl glycol by the Cannizzaro reaction.This research optimized the process conditions for the synthesis of neopentyl glycol by a serial of orthogonal experiments and improved the selectivity and conversion.Amine, for example, triethylamine, was used as the catalyst for the aldol condensation. When the amine concentration is 5%, reaction temperature is 70-75℃ and the mole ratio of formaldehyde and isobutyl aldehyde is 1.2, the reaction selectivity is above 96.8% and the yield is above 96%.And for Cannizzaro reaction, when the mole ratio of formaldehyde and pentaldol is 1.2, reaction temperature is 30-40℃, the pH of reaction solution is controlled over 11, then the crude product is treated by distillation using high boiling point solvent, the yield is above 94% ,the purity of product is above 98% ,and the melt point of the porduct is 122-123℃ .