A series of supported CuO-based nanoparticle catalysts were prepared by the impregnation method and used for the synthesis of glycerol carbonate from glycerol and CO₂ in the presence of 2-cyanopyridine as a dehydrant and DMF as a solvent. The effects of supports (activated alumina, silicon dioxide, graphene oxide, graphene, and activated carbon), CuO loading amount, calcination temperature, and reaction parameters on the catalytic activity of the catalyst were investigated in detail. XRD, FTIR, SEM, BET, and CO₂-TPD were used for the characterization of the prepared catalysts. It is found that CuO/Al₂O₃ shows a higher catalytic activity, which depends on the CuO loading amount and calcination temperature. The surface area and number of basic sites of the catalyst exhibit a crucial effect on the catalytic activity of CuO/Al₂O₃. Furthermore, there is a synergistic effect between the catalyst and 2-cyanopyridine where the former has a higher activation ability for glycerol and the latter acts not only as a dehydrant, but also as a promoter for CO₂ activation. Recycling experiments reveal that this catalyst can be reused for at least five cycles without any inactivation. Based on the experiment results and FTIR characterization, a possible reaction mechanism for the carbonylation of glycerol and CO₂ is proposed.

This paper reports the facile one-pot synthesis of glycidol via the transesterification of glycerol with dimethyl carbonate using KNO₃/Al₂O₃ nanoparticles as supporting catalysts. KNO₃/Al₂O₃ nanoparticles were prepared by the impregnation method. XRD and FT-IR analyses indicated an interaction between KNO₃ and Al₂O₃ that enabled the decomposition of KNO₃ during the process and resulted in the formation of KAl₅O₈, the Al-O-K group, and K₂O. K₂O was recognized as one of the active sites of the catalyst. SEM results indicated the high performance of the supporting catalyst, as the catalytic activity depended on both the number of catalytic active sites and their distribution. The yield of glycidol was 64% at the expense of 95% glycerol under moderate reaction conditions (120 min, 1 atm, and 70 °C). The nanocatalyst prepared at 800 °C with a loading amount of 30% KNO₃ was the most efficient for the synthesis of glycidol. Furthermore, the catalyst was recovered and reused without a loss of efficiency even after the fourth recycling. A plausible mechanism for the one-pot synthesis of glycidol has also been proposed.

A series of Zn salts were used as catalysts for the reaction of glycerol and urea to produce glycerol carbonate and it was found that ZnSO₄ showed the highest catalytic activity. Furthermore, the effects of reaction parameters on the glycerol conversion and glycerol carbonate yield were studied in detail. The results indicated that the glycerol conversion and glycerol carbonate yield were increased with the reaction temperature, reaction time, and catalyst amount while the optimal reaction conditions were 140 °C, 240 min, catalyst amount of 5 wt% (based on the glycerol weight), and urea-to-glycerol molar ratio of 1.1:1. During the reaction, the ZnSO₄ catalyst is transformed into Zn(NH₃)₂SO₄ at the initial stage of the reaction and then further transformed into Zn(C₃H₆O₃). Zn(C₃H₆O₃) and (NH₄)₂SO₄ may be the true active species for the activation of urea and glycerol, respectively. The reaction mechanism is proposed in this article. Based on the experimental results, a reaction kinetics model considering the change in volume of the reaction system was also established, and the model parameters were obtained by fitting the experimental data. The statistical results showed that the established kinetics model is accurate.

In this work we demonstrate one-pot glycidol synthesis, via trans-esterification between glycerol and dimethyl carbonate, by making use of commercially available sodium methoxide as a catalyst. An excellent glycerol conversion (99%) and remarkable glycidol yield (75%) was obtained using dimethyl carbonate/glycerol (molar ratio 2:1) in the presence of 3 wt% catalyst amount (with respect to glycerol weight) at 85 °C for a reaction time of 120 min. Sodium methoxide was recycled and reused twice with only a slight decrease in glycerol conversion. The water content of the glycerol reached 2.5 wt%; this did not reduce the glycerol conversion efficiency of the catalyst. A plausible mechanism for the trans-esterification involved in the preparation of glycidol was proposed.