The CaO/HMCM-22 catalysts were prepared by an ultrasonic impregnation method and their catalytic performances in Knoevenagel condensation were investigated. The characterization results of XRD, SEM, and TPD showed that no significant structural change of MCM-22 was observed after modification by CaO with ultrasonic assistance. Ultrasonic cavitation could reduce the agglomeration between particles and improve the dispersion of CaO on the surface. With the increase of CaO loading, the strength and content of base increased, and the strength of strong acid decreased, while the amount of weak acid sites increased slightly. The catalytic performance of CaO/HMCM-22 prepared by ultrasonic impregnation is better than that of CaO/NaMCM-22 and HMCM-22 for Knoevenagel condensation reactions, which indicates that the catalysts possess both acidic and basic sites after modification. Consequently, the acid–base bifunctional catalysts prepared by the ultrasonic impregnation method maintained high catalytic activity and have improved reusability. Compared with the conventional impregnation method, the strategy developed here is simple and efficient.
Research on Chemical Intermediates – Springer Journals
Published: Apr 10, 2014
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud