TITLE:
Microwave-Assisted Hydrolysis of Hemicellulose over Sulfonated Catalysts
AUTHORS:
Itidel Belkadhi, Mohamed Achraf Bouabdellah, Lassâad Ben Hammouda, Zouhaier Ksibi, Francesco Medina
KEYWORDS:
ZrO2, Al-SBA-15, H-ZSM-5, SO3H, Hemicellulose, Microwave
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.12 No.11,
November
29,
2022
ABSTRACT: Sulfonated catalysts based on zirconia (SO3H-ZrO2), silica (SO3H-SBA-15) and zeolite (SO3H-ZSM-5) were studied in the catalytic hydrolysis reaction of hemicellulose in a microwave reactor. The prepared catalysts were characterized by various techniques (XRD, N2physisorption at 77 K, SEM, TEM and NH3-TPD). The obtained results reveal that despite the differences in their structural and textural properties, the ZrO2, Al-SBA-15 and H-ZSM-5 supports show similar conversions. Doping supports with sulfonate species created hydrogen bonds between SO3H groups and increased the amount of weak acid sites, which enhanced the hydrolysis of hemicellulose. SO3H- ZSM-5 showed the highest catalytic activity followed by SO3H-SBA-15 while SO3H-ZrO2exhibited a poor conversion. Furthermore, the catalytic hydrolysis of the hemicellulose leads to several interesting products, such as formic acid, acetic acid, lactic acid and xylan. The correlation between the catalytic performances and the acidic properties of the different samples indicates that the best catalytic performances were obtained with the least acidic solids and especially when the density of strong acid sites decreases.