Laboratory Simulation of Serpentinization Processes for Sustainable Hydrogen Production

Abstract

Abstract Serpentinization; the hydration of ultramafic rocks represents a natural mechanism for abiotic hydrogen generation with potential renewable energy applications. This study simulates serpentinization reactions under controlled laboratory conditions to evaluate the effect of temperature, pressure, and mineral composition on hydrogen yield. Synthetic olivine (Mg2SiO4) samples were reacted with deionized water in a high-temperature and high-pressure reactor at 80 - 200 °C and 1-5 MPa for 72 h. The formation of serpentine and brucite phases was confirmed via X-ray diffraction and FTIR analysis. Gas chromatography results indicated measurable hydrogen evolution, with the maximum production rate of 2.8 mmol H2 kg−1 rock h−1 at 120 °C, 3 MPa, and pH 9.5. Reaction kinetics followed a pseudo–first-order model, showing a strong correlation (R2 = 0.96) with temperature-dependent rate constants. These findings suggest that low temperature serpentinization can produce hydrogen at rates comparable to natural ultramafic systems, highlighting its potential as a sustainable geological hydrogen source.