Recent Advances in Functionalized Mesoporous Silica Frameworks for Efficient Desulfurization of Fuels

Considerable health and climate benefits arising from the use of low-sulfur fuels has propelled the research on desulfurization of fossil fuels. Ideal fuels are urgently needed and are expected to be ultra-low in sulfur (10-15 ppm), with no greater than 50 ppm sulfur content. Although several sulfur removal techniques are available in refineries and petrochemical units, their high operational costs, complex operational needs, low efficiencies, and higher environmental risks render them unviable and challenging to implement. In recent years, mesoporous silica-based materials have emerged as promising desulfurizing agents, owing to their high porosity, high surface area, and easier functionalization compared to conventional materials. In this review, we report on recent progress in the synthesis and chemistry of new functionalized mesoporous silica materials aiming to lower the sulfur content of fuels. Additionally, we discuss the role of special active sites in these sorbent materials and investigate the formulations capable of encapsulating and trapping the sulfur-based molecules, which are challenging to remove due to their complexity, for example the species present in JP-8 jet fuels.

Recent Advances in Applications of Supported Ionic Liquids

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The supported ionic liquids have shown immense potential for numerous applications in catalysis and separation science. In the present review, the remarkable contribution of supported ionic liquids has been highlighted. The main emphasis has been laid on describing the facile separation of gas from binary gas mixtures owing to the capability of selective transport of permeable gases across supported membranes and removal of environmentally hazard sulfur compounds from fuels. The catalytic action of supported ionic liquids has been discussed in other applications such as biodiesel (biofuel) synthesis by transesterification/esterification processes, waste CO2 fixation into advantageous cyclic carbonates, and various chemical transformations in organic green synthesis. This review enclosed a maximum of the published data of the last ten years and also recently accomplished work concerning applications in various research areas like separation sciences, chemical transformations in organic green synthesis, biofuel synthesis, waste CO2 fixation, and purification of fuels by desulfurization.

New nano-Fe3O4-supported Lewis acidic ionic liquid as a highly effective and recyclable catalyst for the preparation of benzoxanthenes and pyrroles under solvent-free sonication

A novel magnetic nanomaterial-immobilized Lewis acidic ionic liquid was successfully synthesized by the covalent embedding of 3-(3-(trimethoxysilyl)propyl)-1H-imidazol-3-ium chlorozincate (ii) ionic liquid to the surface of Fe₃O₄ nanoparticles. The material was then characterized by FT-IR, SEM, TEM, TGA, ICP-OES, Raman, and EDS. Its performance as a new-generation Lewis acidic catalyst was also examined on the ultrasound-mediated synthesis of benzoxanthenes and pyrroles. Upon completion, the catalyst was simply recovered by an external magnet for multiple reuses without significant lessening of catalytic performance.

A novel magnetically separable catalyst can be used as a green solid Lewis acid catalyst in the synthesis of benzoxanthenes and pyrroles under solvent-free sonication.

Recent Advances in Recoverable Systems for the Copper-Catalyzed Azide-Alkyne Cycloaddition Reaction (CuAAC)

The explosively-growing applications of the Cu-catalyzed Huisgen 1,3-dipolar cycloaddition reaction between organic azides and alkynes (CuAAC) have stimulated an impressive number of reports, in the last years, focusing on recoverable variants of the homogeneous or quasi-homogeneous catalysts. Recent advances in the field are reviewed, with particular emphasis on systems immobilized onto polymeric organic or inorganic supports.

An expedient synthesis of oxazolones using a cellulose supported ionic liquid phase catalyst

A novel cellulose supported ionic liquid phase catalyst has been synthesized and effectively employed as a heterogeneous catalyst in the synthesis of oxazolones.

pH/temperature dependent selective removal of trace Cr(vi) from aqueous solution by imidazolium ionic liquid functionalized magnetic carbon nanotubes

Ionic liquid functionalized magnetic carbon nanotube (Fe₃O₄/CNT-IL) was prepared and used for selective removal of Cr(vi).

One-pot synthesis of ordered mesoporous silica encapsulated polyoxometalate-based ionic liquids induced efficient desulfurization of organosulfur in fuel

Reaction procedure of desulfurization system.