Factors Affecting the Catalytic Performance of Zr,Al-Pillared Clays in the Synthesis of Propylene Glycol Methyl Ether

Synthesis of core-shell Ce-modified mixed metal oxides derived from P123-templated layered double hydroxides

Layered double hydroxides are a promising platform material which can be combined with a variety of active species based on their characteristic features. Silicon@P123-templated Ce-doped layered double hydroxide (SiO2@CeMgAl-LDH(P123)) composites were synthesized via a facile in situ co-precipitation method, and characterized by TEM, X-ray diffraction, FTIR, XPS, CO2-, etc. in detail. Meanwhile, the calcined powder (SiO2@CeMgAl-LDO(P123)) possessed an excellent core-shell structure and a high surface area inherited from the LDH structure, which led to an outstanding catalytic activity (99.7% conversion of propylene oxide, 92.4% selectivity of propylene glycol methyl ether) under mild reaction conditions (120 °C). Cerium oxide provides a large number of oxygen vacancies and significantly improves the medium basic strength of the material, which facilitates the selective ring-opening of PO. Furthermore, the introduction and removal of P123 make the cerium oxide uniformly dispersed on the LDH layers, providing more reaction sites for the reaction of methanol and propylene oxide. The core-shell structure prepared by the in situ co-precipitation method could solve the shortcomings of agglomeration of layered double hydroxides and prolong the catalytic life evidently.

Strategy of regulating the electrophilic/nucleophilic ability by ionic ratio in poly(ionic liquid)s to control the coupling reaction of epoxide

The ionic ratio could control the chemical–physical properties of PILs, and show an enhanced catalytic performance under an optimized ionic ratio in the coupling reaction of epoxide and CO2 or methanol.

Reuse of Pillaring Agent in Sequential Bentonite Pillaring Processes

This work describes the synthesis and characterization of pillared clays using a new pillaring method: the reuse of the pillaring solution. First, an Al pillared clay (PILC) was synthesized, and after filtration, the pillaring agent was stored and reused for an additional three pillaring procedures (P1, P2, and P3). The filtered pillaring solution was stored for one year and then reused for one additional pillaring procedure (P4). The samples were analyzed using XRD, N₂ physisorption measurements and chemical analysis (EDX). All of the samples exhibited basal spacings larger than 17 Å and BET surface areas greater than 160 m²/g. After the P4 pillaring, the pillaring agent was precipitated with a Na₂SO₄ solution, and the resulting solid was analyzed using XRD and SEM. The results indicated that even after a total of five pillaring procedures, Al₁₃ ions were still present in solution. Therefore, it is possible to reuse the pillaring solution four times and to even store the solution for one year, which is important from an industrial perspective.

Hydroxyalkylation of phenol to bisphenol F over Al-pillared clay

Hydroxyalkylation of phenol to bisphenol F over the intercalation of aluminum hydroxy oligomeric into layered montmorillonite K10 was investigated.