Use of crude glycerol from biodiesel producers and fatty materials to prepare allyl esters

Abstract

Vegetable oils and fats are important renewable raw materials for use by the biodiesel industry. One drawback of this industry is the large amounts of glycerol produced as a by-product. Consequently, crude glycerol is moving from a by-product to a residue. New industrial applications for this substance are required. A conversion of this by-product to allyl esters using various fatty materials in a two-step process is reported: After a simultaneous alcoholysis–chlorination reaction of vegetable oils and fats without a solvent, allyl esters were synthesized in a high yield by a rearrangement–elimination reaction using n-butanol as a solvent. All the reactions could be carried out using conventional heating or microwave irradiation with comparable results. Microwave irradiation allows for an important reduction in the reaction time.

This work was supported in part by a Grant-in-Aid for the Secretaría de Estado de Política Científica y Tecnológica of the Spanish Ministry of Education and Culture (Contract grant number: CTQ2006-07451). The authors are grateful to the Comissionat per a Universitats i Recerca del Departament d’Innovació, Universitats i Empresa de la Generalitat de Catalunya and to the the European Social Fund (ESF) for the FI grant of Marc Escribà Gelonch