Mg super(2+)-derived mesoporous ultra-high silica twelve-membered-ring basic zeolites: straightforward synthesis and catalytic performance

• Published in: CrystEngComm Vol. 18; no. 7; pp. 1164 - 1173
• Main Authors: Xie, Jingyan, Wen, Haimeng, Zhang, Wei, Zhou, Yu, Wang, Jun
• Format: Journal Article
• Language: English
• Published: 01.02.2016
• Subjects: Aluminum oxide; Catalysis; Condensing; Magnesium; Silicon dioxide; Strategy; Synthesis; Zeolites
• ISSN: 1466-8033
• DOI: 10.1039/c5ce02075a

Mg super(2+)-derived mesoporous ultra-high silica twelve-membered-ring zeolites with multiple topologies (MOR, BEA and MTW) were straightforwardly synthesized by a one-pot route, where the crucial step was the co-hydrolysis/condensation of silica source and magnesium salt under moderate acidic conditions. SiO sub(2)/Al sub(2)O sub(3 ) ratios can be adjusted from similar to 30 to as high as 410, thus generating superior basicity that was further improved by the incorporation of Mg species. A mesoporous structure was self-formed without the assistance of any template or special strategy. Catalysis tests showed high activity of these zeolites in a typical base reaction, Knoevenagel condensation, even for the bulky substrates due to the enhanced mass transfer arising from the mesopores. This methodology provides a promising approach towards target synthesis of valuable Mg super(2+)-derived mesoporous ultra-high silica zeolites with tunable acid/base properties, which can even act as an efficient mesoporous zeolitic solid base.