TITLE: Correlation of Zeolite ZSM-5 Acid Strength with Catalytic Activity and Selectivity. Final Report.

AUTHOR: D. T. Hayhurst.

INST.  AUTHOR: Cleveland State Univ., OH. Dept. of Chemical Engineering.

SPONSOR: Department of Energy, Washington, DC.

LANGUAGE: English

PUB.  TYPE: Technical Report

PUB.  COUNTRY: United States

SOURCE: Department of Energy [DE],  Apr 84,  30p.

NTIS ORDER NO.: DE85005415/INW

ABSTRACT:

Isosteric heats of ammonia adsorption were determined for several cobalt and cobalt/thorium impregnated H-ZSM-5. Samples were impregnated to the 3, 6 and 9 wt % levels using an incipient wetness technique and either acetone or water for dissolving the metal nitrate salt. The metal impregnation resulted in a lowering of the maximum heat of ammonia adsorption and in a corresponding lowering of the maximum acid site strength. The ammonia adsorption capacity and adsorption heat was unaltered by a reduction of the metal-impregnated samples in hydrogen, indicating that the incipient wetness method leads to cobalt which was most likely ion-exchanged into the zeolite rather than impregnated into the sieve in a reducable form. In addition, the impregnated cobalt caused a slight steric hinderance to the diffusion of n-butane into the metal-loaded zeolite. The use of either water or acetone for dissolving the metal nitrate salt altered the acid-strength distribution. Water was found to lower the acid-site strength to a greater degree than the acetone. 11 references, 8 figures. (ERA citation 10:018787)

REPORT  NUMBER: DOE/PC/51258-T1

CONTRACT  NUMBER: AC22-82PC51258