Production of hydrogen and methane on hydrothermal fluid vent via reduction by hydrogen sulfide

Abstract

Formation of hydrogen and abiotic methane results from serpentinization of ultramafic rocks, though the rate is extremely limited. On the other hand, higher rate of H₂ production from oxidation of hydrogen sulfide is reported, so, we investigated the possibility of H₂ and CH₄ production from sulfur reduction in hydrothermal fluid vent system.We conducted hydrothermal batch-type experiments at the condition hydrothermal fluid vent. Fe₃O₄ was used for mineral catalyst. After 168 [h] experiment, abiotic CH₄ generated  17~10² faster than serpentinization. In this production rate, the concentration of CH₄ measured from hydrothermal fluid vent can be generated within fluid circulation period.