Synthesis of hydrotalcite-type mixed oxide catalysts from waste steel slag for transesterification of glycerol and dimethyl carbonate

Guanhao Liu,Xinru Xu,Jingyi Yang

doi:10.1038/s41598-020-67357-z

Guanhao Liu, Xinru Xu + Show 1 more

Open Access

https://doi.org/10.1038/s41598-020-67357-z

Copy DOI

Abstract

The mixed metal oxides S-CaMgAl MO prepared by acidolysis, coprecipitation and calcination under different temperatures from S95 steel slag of Shanghai Baosteel Co., Ltd. were used to catalyze the transesterification of dimethyl carbonate (DMC) and glycerol for synthesizing glycerol carbonate (GC). The catalysts were characterized by EDS, XRD, FT-IR, SEM, CO2-TPD and nitrogen adsorption–desorption isotherms. S-CaMgAl MO calcined at 600 °C had excellent catalytic performance due to the large pore size and proper alkalinity. The effects of reaction temperature, reaction time and the amount of catalyst on transesterification were investigated to obtain the optimal reaction conditions. The glycerol carbonate yield reached 96.2% and the glycerol conversion was 98.3% under the condition of 3 wt% catalyst, 1:3 molar ratio of glycerol and DMC, 75 °C reaction temperature and 90 min reaction time. In addition, the GC yield and glycerol conversion still achieved above 90% after five cycles of S-CaMgAl MO.

Highlights

The mixed metal oxides S-CaMgAl MO prepared by acidolysis, coprecipitation and calcination under different temperatures from S95 steel slag of Shanghai Baosteel Co., Ltd. were used to catalyze the transesterification of dimethyl carbonate (DMC) and glycerol for synthesizing glycerol carbonate (GC)
The esterification reaction of dimethyl carbonate and glycerol was catalyzed by S-CaMgAl MO calcined at 100 °C 350 °C, 600 °C and 850 °C respectively when the molar ratio of DMC and glycerol was 3:1, the catalyst dosage was 3 wt%, the reaction temperature was 75 °C and the reaction time was 90 min
The results demonstrated that the strength of characteristic peaks corresponded to CaO, MgO and Al2O3 in the X-ray diffraction (XRD) pattern of regeneration catalyst was not weakened significantly compared with the fresh catalyst, which proved that the catalyst had high resistance to metal ion leaching in this reaction system

Summary

Introduction

The mixed metal oxides S-CaMgAl MO prepared by acidolysis, coprecipitation and calcination under different temperatures from S95 steel slag of Shanghai Baosteel Co., Ltd. were used to catalyze the transesterification of dimethyl carbonate (DMC) and glycerol for synthesizing glycerol carbonate (GC). The effects of reaction temperature, reaction time and the amount of catalyst on transesterification were investigated to obtain the optimal reaction conditions. The glycerol carbonate yield reached 96.2% and the glycerol conversion was 98.3% under the condition of 3 wt% catalyst, 1:3 molar ratio of glycerol and DMC, 75 °C reaction temperature and 90 min reaction time. The transesterification of glycerol with DMC over alkaline catalysts is considered a more effective method for the synthesis of GC under mild conditions. Using industrial wastes to prepare heterogeneous solid base catalysts is beneficial to environmental protection, resource recycling and sustainable development. O koye[17] used the calcined blast furnace slag impregnated with NaOH solution to catalyze the esterification of glycerol and dimethyl carbonate

Methods

Results

Conclusion