Analysis of Carbon Dioxide Mineralization in Carbonates from Tampico-Misantla Basin, Mexico: Effect of Organic Matter Content

The pursuit of effective climate change mitigation strategies is driving research into geological carbon dioxide (CO2) storage. The present work explores the interaction of CO2 with carbonate rocks from the El Abra formation in the Tampico-Misantla basin, focusing on the comparative influence of organic matter (OM) content on mineralization processes, hypothesizing that variations in OM content significantly modulate the mineralization process affecting both the rate and type of carbonate formation. Expanding on a previous study, CO2 is studied and injected under high-pressure (1350-2350 PSI) and high-temperature (60–110 °C) conditions into two contrasting samples: one with high OM content and another with low OM content. Structural, morphological, and physical adsorption changes were evaluated through Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) analyses. The findings indicate that the mineralogy of El Abra promotes secondary carbonate precipitation, with rock–fluid interactions significantly enhanced by brine presence. Samples with high OM exhibited a dramatic reduction in average particle size from 13 μm to 2 μm, along with the formation of metastable phases, such as vaterite—evidenced by XRD peak shifting and modifications in the FT-IR spectrum of carbonate bands. Meanwhile, low-OM samples showed an increase in particle size from 1.6 μm to between 3.26 and 4.12 μm, indicating predominant recrystallization. BET analysis confirmed a significant porosity enhancement in high-OM samples (up to 2.918 m2/g). Therefore, OM content plays a critical role in modulating both the rate and type of mineralization, potentially enhancing physical storage capacity in low-OM samples. These integrated findings demonstrate that OM critically governs calcite dissolution, secondary carbonate formation, and microstructural evolution, providing key insights for optimizing CO2 storage in complex carbonate reservoirs.