Microstructure and morphology of mechanically sulfated acid catalysts of α-Al2O3

• Main Author: Costa,T. K. Oliveira
• Publication Date: 2021
• Other Authors: Santos,S. B. F., Silva,C. B., Barros Neto,E. L. de, Pereira,C. G., Freitas,N. L. de
• Format: Article
• Language: eng
• Source: Cerâmica (São Paulo. Online)
• Download full: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0366-69132021000300308
• topic: catalyst; sulfation; esterification; biodiesel

Abstract This work reports the evaluation of the microstructure, morphology, and catalytic behavior of α-Al2O3 synthesized via combustion method for esterification reaction of oleic acid in soybean oil with ethanol to produce biodiesel. The reaction was evaluated with 2 wt% of catalyst at 160 °C for 3 h when the molar ratio of fatty acid:ethanol was 1:12. To enhance the catalytic performance of α-Al2O3, its sulfation was done by a different method using mechanical milling. The microcatalysts were characterized by X-ray diffraction, Fourie transform infrared spectroscopy, granulometric analysis, and scanning electron microscopy. Results showed α-Al2O3 as the major phase, presence of SO4 2- groups, the contribution of the sulfation process to morphology with reduction of agglomerates, and particle size from 18.98 to 15.30 mm. The yield of ester was enhanced from 80% (α-Al2O3 as a catalyst) to 93% (SO4 2-/α-Al2O3 as a catalyst), which showed the milling as a fast method for synthesis of a highly efficient acid catalyst to produce biodiesel.