Reaction of CO2 With Alcohols to Linear-, Cyclic-, and Poly-Carbonates Using CeO2-Based Catalysts

Abstract

Reaction of CO 2 with alcohols to organic carbonates is one of non-reductive CO 2 conversion methods. The catalysts are needed for this reaction, at the same time, effective H 2 O removal methods are also needed because the yield of organic carbonates is strongly limited by the equilibrium. The development of heterogeneous catalysts for the synthesis of dimethyl carbonate from CO 2 and methanol, which is a model and typical reaction, is described. This is because heterogeneous catalysts are more suitable to the practical process than homogeneous catalysts from the viewpoint of the separation of catalysts from the products and the reusability of the catalysts. One of the reported heterogeneous catalysts is CeO 2 , and it has been also reported that the combination of dimethyl carbonate synthesis from CO 2 and methanol with the hydration of nitriles such as 2-cyanopyridine, where both reactions are catalyzed by CeO 2 , enabled high yield of the carbonate. In addition, the combination of CeO 2 catalyst + nitriles can be applied to the synthesis of a variety of linear-, cyclic (five-and six-membered ring)-, and poly-carbonates from CO 2 and corresponding alcohols.

CeO2-Catalyzed Synthesis of 2-Imidazolidinone from Ethylenediamine Carbamate

“…Hence, the development of effective heterogeneous catalysts for the synthesis of organic ureas from the corresponding carbamates is highly desirable. In the previous reports, CeO 2 is one of the effective heterogeneous catalysts for organic urea synthesis from amines with pure and pressurized CO 2 ,, as well as for the synthesis of organic carbonates from alcohols and CO 2 and organic carbamates , from amines, alcohols, and CO 2 . Therefore, CeO 2 is a promising candidate of the heterogeneous catalysts for the conversion of amine carbamates to the corresponding ureas.…”

Copolymerization of carbon dioxide and oxetane catalyzed by aluminum porphyrin complex system

“…Significant progress has been made for the direct carbon dioxide (CO 2 ) conversion into value-added products because CO 2 is a renewable carbon feedstock with its abundance, non-toxicity, non-flammability and inexpensiveness. [1][2][3][4][5] One promising approach to converting CO 2 into useful chemicals is the alternating copolymerization of CO 2 and epoxide (Scheme 1).…”

Direct dimethyl carbonate synthesis from CO2 and methanol catalyzed by CeO2 and assisted by 2-cyanopyridine: a cradle-to-gate greenhouse gas emission study

“…12 In addition to carbonates, carbamate and urea synthesis from CO 2 with the same catalytic system has also been established. 32,[48][49][50] Such CO 2 conversions to chemicals for durable material production can be regarded by society as CO 2 sequestration. The decarbonization in durable material production using chemicals from CO 2 will be an environmentally friendly way to advance a step further toward a sustainable and greener process development.…”

“…42 The combination of nitrile hydration and the reactions with severe equilibrium limitation was found to be effective for high conversion of the target products. [43][44][45][46][47][48][49][50] Honda et al (2013) 25 effectively utilized CeO 2 and 2-CP as a catalyst and dehydration agent, respectively, to directly synthesize DMC. This system achieved a 96% MeOH conversion into DMC by the efficient and quick removal of water that was generated together with DMC during the reaction (eqn (1)) of hydrating 2-CP into 2-picolinamide (2-PA, eqn (2)).…”