Hybrid Catalysts for CO2 Conversion into Cyclic Carbonates

Abstract

The conversion of carbon dioxide into valuable chemicals such as cyclic carbonates is an appealing topic for the scientific community due to the possibility of valorizing waste into an inexpensive, available, nontoxic, and renewable carbon feedstock. In this regard, last-generation heterogeneous catalysts are of great interest owing to their high catalytic activity, robustness, and easy recovery and recycling. In the present review, recent advances on CO 2 cycloaddition to epoxide mediated by hybrid catalysts through organometallic or organo-catalytic species supported onto silica-, nanocarbon-, and metal-organic framework (MOF)-based heterogeneous materials, are highlighted and discussed.

Recent developments in state-of-the-art silica-modified catalysts for the fixation of CO2 in epoxides to form organic carbonates

“…The functionalized silica-based materials are broadly categorized into four classes based on their functionalization with ionic liquids (ILs) including imidazolium, phosphonium, ammonium salts, metal-containing and miscellaneous silica-based catalysts and their use as heterogeneous catalysts for the fixation of CO 2 into cyclic carbonates. 184,185 Each of these sections are reviewed and discussed, showing the functionalization of silica with different types of green and sustainable materials. In general, most functionalized silica-based catalysts show excellent conversion, selectivity and catalytic activities in the cycloaddition of CO 2 with epoxides.…”

Imidazolium-based titanosilicate nanospheres as active catalysts in carbon dioxide conversion: Towards a cascade reaction from alkenes to cyclic carbonates

“…Various solids with Lewis acid character were already developed and tested under heterogenous conditions often in the presence of tetrabutylammonium bromide or iodide in homogeneous phase [46][47][48][49][50]. Few researches describe the synthesis of a material containing both the Lewis acid and the ammonium or imidazolium salts in heterogeneous phase.…”

A Study on the Stability of Carbon Nanoforms–Polyimidazolium Network Hybrids in the Conversion of CO2 into Cyclic Carbonates: Increase in Catalytic Activity after Reuse

“…The combination between ILs and CNFs has been exploited for the production of promising heterogeneous catalytic systems for the fixation of CO 2 into epoxides to form cyclic carbonates [ 35 , 36 , 37 , 38 ]. The fixation of CO 2 into epoxides for the production of cyclic carbonates is of great interest since it represents one of the most explored pathways to valorise CO 2 [ 39 , 40 ]. Despite the large number of research papers dealing with catalytic materials for the conversion of epoxide into cyclic carbonate with CO 2 , the development of hybrid materials based on CNFs and poly ionic liquids is still poorly investigated.…”