ESTERIFICAÇÃO E TRANSESTERIFICAÇÃO SIMULTÂNEAS DE ÓLEOS ÁCIDOS UTILIZANDO CARBOXILATOS LAMELARES DE ZINCO COMO CATALISADORES BIFUNCIONAIS

SIMULTANEOUS ESTERIFICATION AND TRANSESTERIFICATION OF ACID OILS USING LAYERED ZINC CARBOXYLATES AS BIFUNCTIONAL CATALYSTS

Palm oil containing 40% fatty acids was converted to methyl esters using zinc carboxylates as the esterification/transesterification catalyst. The reaction was optimized using a factorial design in which the effects of the alcohol:fatty acids molar ratio (MR_AG) and the catalyst concentration (CAT) were assessed. The best conversion was achieved with CAT at 4 wt% and MR_AG at 4:1. However, the solid catalyst presented significant structural changes after use. For instance, laurate anions were replaced by carboxylates of higher molecular mass, leading to the formation of a new catalytically active layered structure. Also, the glycerin obtained as a co-product contained 86 wt% glycerol.

zinc carboxylates; acid oils; methyl esters