2024-07-182024-07-182022RIBEIRO, Stephany L. S. et al. Nickel-cobalt hydroxide catalysts for the cycloaddition of carbon dioxide to epoxides. Research on Chemical Intermediates, [s. l.], v. 48, p. 1907-1921, 2022. DOI: 10.1007/s11164-022-04697-7. Disponível em: https://link.springer.com/article/10.1007/s11164-022-04697-7. Acesso em: 5 jul. 2024.e- 1568-56750922-6168https://link.springer.com/article/10.1007/s11164-022-04697-7Nickel and cobalt bimetallic hydroxides, in which both metal cations present the same oxidation state, were synthesized and characterized by XRD, TGA, TEM, XPS, and ICP-OES. The catalytic activity in the cycloaddition of carbon dioxide with epoxides was evaluated in a binary system, using tetrabutylammonium bromide as cocatalyst. All materials were active catalysts for the production of cyclic carbonates in the initial conditions, providing conversions and selectivities up to 75% and 93%, respectively. The influence of the parameters time, temperature, catalyst amount, pressure, and cocatalyst type was examined. Using the catalyst with the molar ratio 50:50 of Ni and Co (NiCo-50), a series of epoxides was converted to the respective carbonates under the optimal conditions, providing excellent conversions and selectivity. Alkylic propylene oxide and butylene oxide presented 84% and 83% of conversion, respectively. For epoxides containing electron-withdrawing substituents, the conversions were quantitative (> 99%) and highly selective to the cyclic carbonate. Reuse experiments were conducted, and showed that NiCo-50 can be recovered and reused at least five times, without decline in conversion and selectivity.engAcesso RestritoNickel cobalt hydroxideCarbon dioxideCO2 fixationCyclic carbonateHeterogeneous catalysisHydrogen bond donorArtigo10.1007/s11164-022-04697-7