Preparação de suportes micro e mesoporosos para imobilização de lipase e aplicação na esterificação do ácido oléico

Abstract

This study aimed to prepare and characterize heterogeneous catalysts using immobilized enzymes in MCM-41 supports and metakaolin. The supports were functionalized with APTES (an amine) for application to the oleic acid esterification reaction with methanol to produce ester. The characterization of the catalyst was made by XRD, FT-IR, physisorption of N2 and spectrometry of UV. The results show that MCM-41 has been effectively functionalized and immobilized enzymes were, however, there was a partial loss of the hexagonal array of such support, while for metakaolin, both functionalization as immobilization did not occur satisfactorily. Using UV spectrometry, it was found that around 80% of the enzymes were effectively immobilized on MCM-41. This biocatalyst (heterogeneous) was tested in the esterification of oleic acid (molar ratio to oleic acid / methanol was 1:15), at a temperature of 30 °C (100 rpm) for 12h. The obtained conversion was 52% of acid mass to ester, indicating that there viability on the use of MCM-41 amine functionalized for the immobilization of lipase, since catalytic activity of the enzyme was preserved. As for metakaolin, the results showed that, despite having been initially some connection enzymes to metakaolin functionalized, UV spectrometry showed that the anchoring enzyme was not effective in the course of 4 hours, however, new methodological approaches to this material may be applied to ensure the efficient functionalization and immobilization.