Efficient and reusable SBA-15-immobilized Brønsted acidic ionic liquid for the ketalization of cyclohexanone with glycol

Isomerization of C7 and C8 through Ionic Liquids Supported by a Fe/SBA-15 Catalyst

Isomerization is extensively utilized in the petroleum industry, and this study demonstrates an energy-efficient process utilizing an ionic liquid catalyst. 1-Ethyl-3-methylimidazolium triflate [Emim][TFO] as an ionic liquid was immobilized on solid support Fe/SBA-15. Variants of the catalyst were developed with the Fe constant at 5% and different ratios of ionic liquid. In the catalyst Fe/[Emim][TFO]/SBA-15, the metal Fe was loaded via the impregnation method, and subsequently, the ionic liquid variants Fe/[Emim][TFO](10)/SBA-15, Fe/[Emim][TFO](20)/SBA-15, and Fe/[Emim][TFO](30)/SBA-15 were synthesized. The physical properties of the synthesized catalyst were studied using standard characteristic techniques. The process performance was studied for variants of each parameter, which include temperature, hydrogen flow rate, pressure, and weight hourly space velocity. The iso-products of n-heptane and n-octane were obtained with an appreciable conversion of >90% and a selectivity of >95% with the catalyst Fe/[Emim][TFO](20)/SBA-15 among the other synthesized catalysts. The process yielded a high quantum of iso-products with negligible cracked products at a low temperature of 140 °C. The catalyst Fe/[Emim][TFO](20)/SBA-15 at 140 °C delivered the highest yield of iso-alkanes among the three catalysts. Iso-alkanes are instrumental tools for increasing the octane number of a fuel. This study delivers high iso-alkane content fuel, which can provide the best anti knock capability and enhance fuel efficiency for the life of modern high-powered engines. The results demonstrate a process that is energy-efficient, economic, and environmentally friendly.

Preparation of magnetic silica supported Brönsted acidic ionic liquids for the depolymerization of lignin to aromatic monomers

Lignin, the most abundant renewable resource of aromatics in nature, is recognized as an alternative for fossil-based fuels and chemicals. Herein, we proposed an efficient method to obtain aromatic monomers...

Functionalized Silicas for Metal-Free and Metal-Based Catalytic Applications: A Review in Perspective of Green Chemistry

Heterogeneous catalysis plays a key role in promoting green chemistry through many routes. The functionalizable reactive silanols highlight silica as a beguiling support for the preparation of heterogeneous catalysts. Metal active sites anchored on functionalized silica (FS) usually demonstrate the better dispersion and stability due to their firm chemical interaction with FSs. Having certain functional groups in structure, FSs can act as the useful catalysts for few organic reactions even without the need of metal active sites which are termed as the covetous reusable organocatalysts. Magnetic FSs have laid the platform where the effortless recovery of catalysts is realized just using an external magnet, resulting in the simplified reaction procedure. Using FSs of multiple functional groups, we can envisage the shortened reaction pathway and, reduced chemical uses and chemical wastes. Unstable bio-molecules like enzymes have been stabilized when they get chemically anchored on FSs. The resultant solid bio-catalysts exhibited very good reusability in many catalytic reactions. Getting provoked from the green chemistry aspects and benefits of FS-based catalysts, we confer the recent literature and progress focusing on the significance of FSs in heterogeneous catalysis. This review covers the preparative methods, types and catalytic applications of FSs. A special emphasis is given to the metal-free FS catalysts, multiple FS-based catalysts and magnetic FSs. Through this review, we presume that the contribution of FSs to green chemistry can be well understood. The future perspective of FSs and the improvements still required for implementing FS-based catalysts in practical applications have been narrated at the end of this review.