TITLE: Superacid catalysis of light hydrocarbon conversion. DOE PETC third quarterly report, February 25, 1994--May 24, 1994.

AUTHOR: B. C. Gates.

INST.  AUTHOR: Delaware Univ., Newark. 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],  1995,  11p.

NTIS ORDER NO.: DE95004323INW

ABSTRACT:

Environmental concerns are leading to the replacement of aromatic hydrocarbons in gasoline by high-octane-number branched paraffins and oxygenated compounds such as methyl t-butyl ether. The ether is produced from methanol and isobutylene, and the latter can be formed from n-butane by isomerization followed by dehydrogenation. Paraffin isomerization reactions are catalyzed by very strong acids such as aluminum chloride supported on alumina. The aluminum chloride-containing catalysts are corrosive, and their disposal is expensive. Alternatively, hydroisomerization is catalyzed by zeolite-supported metals at high temperatures, but high temperatures do not favor branched products at equilibrium. Thus there is a need for improved catalysts and processes for the isomerization of n-butane and other straight-chain paraffins.  Consequently, researchers have sought for solid acids that are noncorrosive and active enough to catalyze isomerization of paraffins at low temperatures. For example, sulfated zirconia catalyzes isomerization of n-butane at temperatures as low as 25(degrees)C. The addition of iron and manganese promoters has been reported to increase the activity of sulfated zirconia for n-butane isomerization by three orders of magnitude.  Although the high activity of this catalyst is now established, the reaction network is not known, and the mechanism has not been investigated. The goal of this work is to investigate low-temperature reactions of light paraffins catalyzed by solid superacids of the sulfated zirconia type. The present report is concerned with catalysis of n-butane conversion catalyzed by the Fe- and Mn- promoted sulfated zirconia described in the previous report in this series.

REPORT  NUMBER: DOE/PC/92116-T3

CONTRACT  NUMBER: AC22-93PC92116