ISSN:
1573-4854
Keywords:
chromium oxalate
;
chromium oxide CrO x
;
nitrogen adsorption-desorption
;
porosity
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The porosity of oxides has an influence on their catalytic activity. An accurate knowledge of the effects of thermal treatments on the textural characteristics of oxides obtained by precursors decomposition is therefore an essential step. The porosity of the studied chromium oxides was analyzed by nitrogen adsorption-desorption measurements. Decomposition under air at 310–340°C of chromium oxalate allowed us to obtain more or less microporous X-ray amorphous chromium oxides, CrO x (x ≈ 2), according to the heating and cooling rates and the treatment temperatures used. The oxides obtained from chromium hydroxides were mesoporous and had lower specific surface areas. Using high heating and cooling rates for the oxalate decomposition, the prepared chromium oxides were more microporous. By this way, the control of the textural properties of the resulting oxides is possible.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01134029
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