Formation of carbides and hydrocarbons in chondritic interplanetary dust particles: A laboratory study

Abstract

Abstract— The reaction between kamacite grains and H2 + CO gas mixture has been tested in the laboratory under experimental conditions presumed for interplanetary dust particle (IDP) formation in a nebular‐type environment (H2:CO = 250:1; 5 × 10−4 atm total pressure, and 473 K). Carbon deposition, hydrocarbon production in the C1–C4 range, and the formation of an ɛ‐carbide phase occur when well‐defined model FeNi bcc alloy (kamacite) particles are exposed to a mixture of H2 + CO during 103 h. These results strongly support the idea that gas‐solid reactions in the solar nebula during CO hydrogenation represent a plausible scenario for the formation of carbides and carbonaceous materials in IDPs, as well as for the production of hydrocarbons through Fischer‐Tropsch‐type reactions.