TY - JOUR
T1 - Modified natural dolomite and its influence on the production of glycerol carbonate
T2 - Effects of structural and basicity properties
AU - González-García, Julio
AU - Chen, Lifang
AU - Campuzano-Calderon, Omar
AU - Núñez-Correa, Sara
AU - López-Guajardo, Enrique A.
AU - Wang, Jin An
AU - Montesinos-Castellanos, Alejandro
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021
Y1 - 2021
N2 - A systematic study over different treatment conditions, including hydrothermal and acidthermal, was successfully carried out to determine the most suitable conditions to enhance the textural properties and surface chemical composition of natural dolomite. The reconstruction of dolomite after various treatments enhanced the surface area by 4-5 times and diminished the pore diameter between 70% and 81% compared to the untreated parent dolomite. The Rietveld analysis of the X-ray diffraction (XRD) patterns revealed changes in the crystalline compositions after each treatment. When the treated dolomite was used as a catalyst to produce glycerol carbonate via a transesterification reaction of glycerol and dimethyl carbonate, the crystalline Ca(OH)2 concentration of the modified dolomite and the apparent glycerol carbonate formation rate (rgc) are well-correlated. The results suggest that an increase of the crystalline Ca(OH)2 concentration could be related with surface basicity at the weak and moderate strength sites that may lead to an increase in catalytic activity. The hydrothermal treated dolomite showed a selectivity of glycerol carbonate greater than 99% and rgc value 3.42 mmol/min.gcat, which was higher than that achieved on other samples. This study could aid to the proper selection of dolomite treatment for the desired crystalline composition, depending on the applications of this highly available mineral.
AB - A systematic study over different treatment conditions, including hydrothermal and acidthermal, was successfully carried out to determine the most suitable conditions to enhance the textural properties and surface chemical composition of natural dolomite. The reconstruction of dolomite after various treatments enhanced the surface area by 4-5 times and diminished the pore diameter between 70% and 81% compared to the untreated parent dolomite. The Rietveld analysis of the X-ray diffraction (XRD) patterns revealed changes in the crystalline compositions after each treatment. When the treated dolomite was used as a catalyst to produce glycerol carbonate via a transesterification reaction of glycerol and dimethyl carbonate, the crystalline Ca(OH)2 concentration of the modified dolomite and the apparent glycerol carbonate formation rate (rgc) are well-correlated. The results suggest that an increase of the crystalline Ca(OH)2 concentration could be related with surface basicity at the weak and moderate strength sites that may lead to an increase in catalytic activity. The hydrothermal treated dolomite showed a selectivity of glycerol carbonate greater than 99% and rgc value 3.42 mmol/min.gcat, which was higher than that achieved on other samples. This study could aid to the proper selection of dolomite treatment for the desired crystalline composition, depending on the applications of this highly available mineral.
KW - Acid treatments
KW - Crystalline composition
KW - Glycerol carbonate
KW - Natural dolomite
KW - Surface basicity
UR - http://www.scopus.com/inward/record.url?scp=85105603052&partnerID=8YFLogxK
U2 - 10.3390/ma14092358
DO - 10.3390/ma14092358
M3 - Artículo
C2 - 34062768
AN - SCOPUS:85105603052
SN - 1996-1944
VL - 14
JO - Materials
JF - Materials
IS - 9
M1 - 2358
ER -