Laboratory studies of catalysis of CO to organics on grain analogs

Experiments simulating heterogeneous conversion of H-2 and CO into simple h ydrocarbons in astrophysical environments have been performed, utilizing re alistic cosmic grain analogs of Fe-doped silicates as Fischer-Tropsch-Type catalysts. Catalysis was studied for temperatures from 470-670 K and reacta nt gas mixtures of H-2/CO with a ratio of 2-100. The total gas pressure was near 0.5 bar. Maximum conversion rates of a few percentage points were ach ieved over a 3-h time period. Major products were methane, ethane, ethylene , carbon dioxide, and water. Products were identified by IR. spectroscopy. (C) 2000 Academic Press.