Alquilación de m-cresol con 2-propanol sobre catalizadores ácidos

ACEVEDO, MAURO D.; OKULIK, NORA B.; PADRÓ, CRISTINA L.

Santa Fe

Congreso; XXI Congreso Argentino de Catálisis y el X Congreso de Catálisis del Mercosur; 2019

SACAT

In this work, the alkylation reaction of m-cresol with 2-propanol (IPA) in gas phase on solid acid catalysts was studied. The acidity of the catalysts was determined by FTIR of pyridine and TPD of NH3.The influence of the characteristics of the catalysts was studied using HBEA, ZnY and HZSM5. UsingHBEA, a decrease in the conversion was observed when the temperature increased, either due to increased deactivation or thermodynamic limitation. By varying the contact time it could be concluded that 2-isopropyl-5-methylphenol (thymol) is a primary product that is formed predominantly at low conversions (and to a lesser extent 4-isopropyl-3-methylphenol is formed) (4I3MF) and is converted to the more stable isomer 3-isopropyl-5-methylphenol (3I5MF) when increasing the conversion. The conversion of m-cresol on ZnY was lower than on HBEA, despite the fact that ZnY zeolite has higher concentration of acid sites than HBEA indicating that the strong Lewis acid sites that this material possesses would be less active in this reaction. HZSM5 was almost inactive, which may be due to diffusive limitations. Probably due to the low conversion, the selectivity to thymol was high (80%) on this catalyst. O-alkylation products were not formed on any catalyst or condition used.