چكيده لاتين
With the increase of greenhouse gases in recent years, especially carbon dioxide, and the resulting major problems such as global warming, reducing carbon dioxide production and preventing its release into the Earth’s atmosphere has attracted significant attention. Among the methods of preventing the emission of carbon dioxide into the atmosphere is the chemical fixation of carbon dioxide with epoxides, which not only reduces carbon dioxide emissions but also produces high-value cyclic carbonates. These cyclic carbonates are used in polar solvents, electrolytes in lithium batteries, pharmaceuticals, and as precursors of polycarbonates.
To carry out the chemical fixation reaction of carbon dioxide, due to the high stability of carbon dioxide, the use of a catalyst is required. In this study, the catalyst used was a copper-based metal–organic framework containing silver nanoparticles (Ag@Cu-TDPAT), selected together with tetrabutylammonium bromide (TBAB) as a co-catalyst. The advantages of this catalyst include simple and accessible raw materials, a short synthesis process, and the possibility of use without an activation step.
Furthermore, the effects of various parameters such as the amount of catalyst, the amount of co-catalyst, temperature, carbon dioxide pressure, and reaction time were investigated, and a set of conditions was selected as the optimal values for the chemical fixation reaction (65 mg catalyst, 100 mg co-catalyst, temperature of 110 °C, CO₂ pressure of 20 bar, reaction time of 8 hours, and 2 ml styrene oxide).
The Ag@Cu-TDPAT catalyst under optimal conditions and in a solvent-free system was used for the cycloaddition reaction of carbon dioxide to styrene oxide, showing a 92% conversion of styrene oxide with 88% selectivity. Finally, a study was conducted on the recyclability of the catalyst, which demonstrated its stability after several uses.
