Promoter modifications of catalytic activity and selectivity. Progress report, April 1, 1982-November 30, 1983

Technical Report · Wed Nov 30 04:00:00 EST 1983

OSTI ID:5659377

Falconer, J L

Carbon monoxide hydrogenation to methane and higher hydrocarbons was changed significantly by the addition of alkali promoters to supported nickel catalysts. Alkali promoters in general were observed to decrease activity and increase olefin selectivity. However, the oxide support significantly affects the modifications induced by the promoters. On SiO/sub 2/, Al/sub 2/O/sub 3/ and TiO/sub 2/, overall activity decreased; on SiO/sub 2/.Al/sub 2/O/sub 3/, activity increased with promoters and a maximum was observed at low potassium concentrations. Differential reactor studies were also used to show that the support and promoter concentrations had a larger influence on activity and selectivity than catalyst preparation (pre-, co- or postimpregnation) and promoter salt used (KCl, K/sub 2/CO/sub 3/, K/sub 2/C/sub 2/O/sub 4/, KOH). Temperature-programmed reaction (TPR) also showed that alkali decreased the rates of both carbon monoxide and carbon hydrogen; the decreased rates were not due to site blocking. Excellent agreement was obtained between TPR and steady-state kinetics. Temperature-programmed desorption indicated that the decreased hydrogenation rates of CO, carbon and of olefin were due to weakened hydrogen bonding. The CO desorption was also significantly changed by promotion.

• Research Organization: Colorado Univ., Boulder (USA). Dept. of Chemical Engineering
• DOE Contract Number: AC02-82ER12058
• OSTI ID: 5659377
• Report Number(s): DOE/ER/12058-2; ON: DE84003179
• Country of Publication: United States
• Language: English

Related Subjects

090121* -- Hydrocarbon Fuels-- Chemical Synthesis-- (1976-1989)
10 SYNTHETIC FUELS
ADDITIVES
ALKALI METALS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CATALYSTS
CHALCOGENIDES
CHEMICAL REACTIONS
DESORPTION
ELEMENTS
HYDROGENATION
METALS
METHANATION
NICKEL
OXIDES
OXYGEN COMPOUNDS
POTASSIUM
RESEARCH PROGRAMS
SILICON COMPOUNDS
SILICON OXIDES
SODIUM
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS