New insights of geochemical interactions between h2 and minerals in underground hydrogen storage: Experimental studies and geochemical simulation

Underground hydrogen storage (UHS) has emerged as one of the most promising technologies for addressing the critical demand for large-scale clean energy storage. However, current understanding of the geochemical behavior of H 2 interacting with minerals within underground reservoirs remains limited. This paper employed a self-developed high-temperature, high-pressure apparatus to study the geochemical interactions in hydrogen-water-mineral systems. Four common diagenetic minerals were exposed to H 2 -saturated water for eight weeks under conditions of 333 K and 15 MPa. Multiple methods, including XRD, SEM, GC, ICP-MS, and geochemical modeling, were employed to evaluate the impact on minerals. Results show that the tested minerals remained stable under prolonged H 2 exposure, with no significant changes in composition or microstructure. Under the tested conditions and at the analytical resolution employed, no H 2 -induced mineral dissolution or changes in gas composition were detected. These findings clarify the dynamic characteristics of H 2 -mineral abiotic interactions, providing a key theoretical basis for assessing the safety and long-term stability of underground hydrogen storage.