Acetylation of Eugenol over 12-Molybdophosphoric Acid Anchored in Mesoporous Silicate Support Synthesized from <i>Flint</i> Kaolin

• Main Authors: Alex de Nazaré de Oliveira, Erika Tallyta Leite Lima, Deborah Terra de Oliveira, Rômulo Simões Angélica, Eloisa Helena de Aguiar Andrade, Geraldo Narciso da Rocha Filho, Carlos Emmerson Ferreira da Costa, Fabiola Fernandes Costa, Rafael Luque, Luís Adriano Santos do Nascimento
• Format: Article
• Language: English
• Published: MDPI AG 2019-09-01
• Series: Materials
• Subjects: acetylation; eugenyl acetate; 12-molybdophosphoric acid; <i>flint</i> kaolin; AlSiM; heterogeneous catalysis
• Online Access: https://www.mdpi.com/1996-1944/12/18/2995

A new prepared catalyst, 12-molybdophosphoric acid (HPMo) anchored to the mesoporous aluminosilicate AlSiM, synthesized from Amazon kaolin, was characterized and used as a heterogeneous acid catalyst for the production of eugenyl acetate by acetylation of eugenol with acetic anhydride. The effect of various reaction parameters, such as catalyst concentration, eugenol/acetic anhydride molar ratio, temperature and reaction time, was studied to optimize the conditions of maximum conversion of eugenol. The kinetics studies showed that in eugenol acetylation, the substrate concentration follows a first order kinetics. The results of activation energy was 19.96 kJ mol^&#8722;1 for HPMo anchored to AlSiM. The reuse of the catalyst was also studied and there was no loss of catalytic activity after four cycles of use (from 99.9% in the first cycle to 90% in the fifth cycle was confirmed), and an excellent stability of the material was observed. Based on catalytic and kinetic studies, HPMo anchored to AlSiM is considered an excellent catalyst.