TY - JOUR
T1 - Nanostructured chromium-iron mixed oxides
T2 - Physicochemical properties and catalytic activity
AU - Khaleel, Abbas
AU - Shehadi, Ihsan
AU - Al-Shamisi, Mariam
N1 - Funding Information:
This work was financially supported by the UAE University , Grant number 06-03-2-11/07 . The authors thank Professor G. Buzzell and Dr. S. Tariq, Faculty of Medicine and Health, UAE University, for the TEM micrographs.
PY - 2010/2/20
Y1 - 2010/2/20
N2 - Chromium-iron bulk mixed oxides were prepared by a sol-gel method using 2-propanol solutions of the nitrate salts of both metals, and propylene oxide as a gelation promoter. Composites with iron content of 10%, 50% and 90% were prepared and compared with the corresponding pure oxides, α-Fe2O3 and Cr2O3. The mixed oxides were characterized by XRD, TEM, FT-IR, and N2 adsorption. The XRD analysis indicated the formation of solid solutions of the mixed oxides which exhibited significantly modified textural characteristics, as indicated by N2 adsorption studies. The characteristics of the mixed oxides were dependent on the Cr/Fe ratio and the composite with 50% Fe, in particular, exhibited significantly higher specific surface areas and porosity than other composites and pure oxides. The catalytic conversion of methanol was studied at 225 °C. The catalytic activities exhibited by the mixed oxides were significantly higher than those of the pure oxides. The yields of the products, dimethyl ether (DME), methyl formate (MF), and CO2 were dependent on the Cr/Fe ratio.
AB - Chromium-iron bulk mixed oxides were prepared by a sol-gel method using 2-propanol solutions of the nitrate salts of both metals, and propylene oxide as a gelation promoter. Composites with iron content of 10%, 50% and 90% were prepared and compared with the corresponding pure oxides, α-Fe2O3 and Cr2O3. The mixed oxides were characterized by XRD, TEM, FT-IR, and N2 adsorption. The XRD analysis indicated the formation of solid solutions of the mixed oxides which exhibited significantly modified textural characteristics, as indicated by N2 adsorption studies. The characteristics of the mixed oxides were dependent on the Cr/Fe ratio and the composite with 50% Fe, in particular, exhibited significantly higher specific surface areas and porosity than other composites and pure oxides. The catalytic conversion of methanol was studied at 225 °C. The catalytic activities exhibited by the mixed oxides were significantly higher than those of the pure oxides. The yields of the products, dimethyl ether (DME), methyl formate (MF), and CO2 were dependent on the Cr/Fe ratio.
KW - Chromium-iron
KW - Methanol conversion
KW - Mixed oxides
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U2 - 10.1016/j.colsurfa.2009.11.041
DO - 10.1016/j.colsurfa.2009.11.041
M3 - Article
AN - SCOPUS:74149089622
SN - 0927-7757
VL - 355
SP - 75
EP - 82
JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects
JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects
IS - 1-3
ER -