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Gysi, Alexander

Publications and source records attributed to Gysi, Alexander.

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

The potential for New Mexico basalts to sequester CO2 with a focus on critical element mobility

This study investigates the potential for New Mexico basalts to serve as geologic CO₂ sequestration media through mineral carbonation. Batch-type experiments were conducted using crushed basalts from the Carrizozo and Taos regions at low PCO₂ (0.7–2 bar) and temperatures up to 40°C over 180 days. The experiments evaluated the kinetics of CO₂-water-rock interaction, cation release, and critical element mobility (Cu, Ni, Co, Zn). Solid and fluid samples were analyzed using SEM, EMPA, ICP-OES, and ICP-MS, and geochemical modeling was performed with GEM-Selektor and PHREEQC. Results indicated that up to 80% of the injected CO₂ was mineralized within 100 days, forming secondary carbonates such as siderite and ankerite. Additionally, significant mobilization of critical metals was observed, which has implications for resource recovery and mine-waste valorization in future CO₂ sequestration projects.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

The potential for New Mexico basalts to sequester CO 2 with a focus on critical element mobility

This study evaluates the potential of New Mexico basaltic rocks and mafic mine waste for CO₂ sequestration via mineral carbonation. Batch experiments up to 200 days at 40°C simulated CO₂-bearing fluid interactions with various crushed basaltic materials at different grain sizes. Results showed that 70–80% of injected CO₂ was mineralized, with the finest grain sizes showing the most rapid and effective drawdown. The experiments also assessed the mobility of critical metals (Cu, Ni, Zn, Co), revealing trends tied to mineral dissolution and secondary mineral formation. The findings support the dual potential of mine waste for CO₂ sequestration and critical element recovery, informing future carbon capture and resource upcycling strategies.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

The CO2 mineralization potential of New Mexico basalts and associated critical element behavior and mobility.

This presentation reports on laboratory experiments assessing the carbon dioxide (CO₂) mineralization potential of New Mexico basalts, including trachybasalt and basalt lithologies. Using simulated groundwater and controlled conditions, the study evaluates the kinetics of CO₂ sequestration, mineral saturation indices, and secondary mineral formation. It also investigates the mobility of critical and trace elements such as Ni, Zn, Cu, and Li during basalt dissolution. Results indicate that New Mexico basalts can effectively sequester CO₂ through carbonate formation, with grain size and mineral composition influencing reaction rates and elemental behavior. These findings support the viability of geologic carbon storage in mafic volcanic terrains and inform strategies for critical element recovery.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Linear Correlations of Gibbs Free Energy of REE Phosphates (Monazite, Xenotime, and Rhabdophane) and Internally Consistent Binary Mixing Properties

Rare Earth Elements (REE) phosphates (monazite, xenotime, and rhabdophane) are critical REE-bearing minerals typically formed in hydrothermal and magmatic ore deposits. The thermodynamic properties of those REE minerals are crucial to understanding the solubility, speciation, and transport of REE complexes. However, the standard-state Gibbs free energy of formation (∆G°f) values reported for these minerals in the literature vary by up to 25 kJ mol−1. Here, we present linear free energy relationships that allow the evaluation and estimation of the ∆G°f values at 25 °C and 1 bar for the three minerals from the ionic radius (rREE3+) and the non-solvation Gibbs free energy contribution to the REE3+ aqua ion (∆G°n, REE3+): ∆G°f,monazite − 399.71 rREE3+ = 1.0059 ∆G°n,REE3+ − 2522.51; ∆G°f,xenotime − 344.08 rREE3+ = 0.9909 ∆G°n,REE3+ − 2451.53; and ∆G°f,rhabdophane − 416.17 rREE3+ = 1.0067 ∆G°n, REE3+ − 2688.86. Moreover, based on the new dataset derived for REE end-members, we re-fitted the binary Margules parameter (W) from previous theoretical calculations into linear correlations: W + 0.00204 ∆G°’n,monazite = 39.3549 ∆V + 0.0641; W + 0.00255 ∆G°’n,xenotime = 25.4885 ∆V − 0.0062. The internally consistent thermodynamic properties of these REE phosphates are incorporated into the computer program Supcrtbl, which is available online at Zhu’s research website.

Pan, Ruiguang (ORCID:0000000324896545)↗