A New Aproach for Studying the Acid Strength Distribution in Hydrotreating Catalysts by Differential, Scanning Calorimetry

A. M. Summan

Department of Chemistry, Facuity of Applied Science & Engineering, Umm Al-Qura University, P. O. Box 3711, Mokkah Al-Mukarrawah (Saudi Arabia)

ABSTRACT:

Three hydrotreating catalysts in the oxide form, Co-Mo-a umina & Ni ~Mo~ alumina, have been subjected to triethylamine (TEA) adsorption until saturation followed by its desorption in a differential scanning calorimetry (DSC) until via a programmed increased temperature. All catalysts show three DSC effects, in the temperature ranges 50-220. 220 - 420 and 420-600 °C, indicating three groups of acid sites, described here as weak, intermediate strength and strong, respectively. For the cobalt -molybdate catalyst, the strong sites effect appears to have a lower strength than for the two other catalysts. The number of strong acid sites can be arranged in decreasing order as follows: Ni-W-alumina > Co-Mo-alumina > Ni- Mo^alumina. The number of intermediate strength acid sites can be arranged in the order Ni- Mo-alumina> Co-Mo-alumina > Ni-W-alumina, whereas the strength of this type is in the order Ni~W« alumina > Co-Mo-alumina > Ni-Mo-alumina, The strength and number of the strongest acid sites has been found to correlate will with the efficiency of these catalysts to the hydrodenitrogenate aniline.

KEYWORDS:

Studying; Differential; Calorimetry

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Copy the following to cite this article: Summan A. M. A New Aproach for Studying the Acid Strength Distribution in Hydrotreating Catalysts by Differential, Scanning Calorimetry. Orient J Chem 1990;6(3).

Copy the following to cite this URL: Summan A. M. A New Aproach for Studying the Acid Strength Distribution in Hydrotreating Catalysts by Differential, Scanning Calorimetry. Orient J Chem 1990;6(3). Available from: http://www.orientjchem.org/?p=40228