Acetalization of glycerol with ketones and aldehydes catalyzed by high silica Hβ zeolite

• Published in: Molecular catalysis 2019-12, Vol.479, p.110608, Article 110608
• Main Authors: Poly, Sharmin Sultana, Jamil, Md.A.R., Touchy, Abeda S., Yasumura, Shunsaku, Siddiki, S.M.A. Hakim, Toyao, Takashi, Maeno, Zen, Shimizu, Ken-ichi
• Format: Article
• Language: English
• Subjects: Acetalization; Glycerol; Hydrophobicity; Zeolites
• ISSN: 2468-8231; 2468-8231
• DOI: 10.1016/j.mcat.2019.110608

[Display omitted] •High silica Hβ zeolite acts as an effective heterogeneous and transition metal-free catalyst for acetalization of glycerol.•This catalyst system is applicable to acetalization of glycerol with various ketones/aldehydes and recyclable without significant loss of its activity.•The high efficiency is attributed to the tailored hydrophobic nature of the catalyst surface, a sufficient number of accessible acid sites, and a larger pore size. In this work, proton-exchanged *BEA zeolite with a high Si/Al ratio of 75 (Hβ-75), was demonstrated as an effective catalyst for the acetalization of glycerol with carbonyl compounds. This catalyst system was applicable to various substrates and reusable for at least 4 times with slight decrease in activity. The turnover frequency, based on acid site concentration, increased as a function of Hβ Si/Al ratio, indicating the importance of the zeolite hydrophobic surface properties. The origin of the high efficiency exhibited by Hβ-75 is quantitatively discussed based on kinetic studies, hydrophobicity, and acid site concentration.