Pyrogenic carbon and carbonating minerals for carbon capture and storage (PyMiCCS) part II: organic and inorganic carbon dioxide removal in an Oxisol

作者：Maria-Elena Vorrath, Thorben Amann, Johannes Meyer zu Drewer, Nikolas Hagemann, Cierra Aldrich, Janine Börker, Maria Seedtke, Joscha N. Becker, Mathilde Hagens, Annette Eschenbach, Jens Hartmann · 发表于：Frontiers in Climate · 年份：2025 · DOI：10.3389/fclim.2025.1592454 · 被引用次数：9 · 研究领域：Carbon Dioxide Capture Technologies、CO2 Sequestration and Geologic Interactions、Zeolite Catalysis and Synthesis

Enhanced rock weathering (ERW) and pyrogenic carbon capture and storage (PyCCS, or “biochar carbon removal”) are two promising carbon dioxide removal (CDR) techniques that can contribute to soil restoration. These technologies can be combined by co-application of rock powder and biochar or by co-pyrolysis of rock powder with biomass to produce rock-enhanced (RE) biochar. In a 27-week laboratory experiment, we quantified the carbon (C) sink development of co-applications and RE-biochars produced by co-pyrolysis of basanite rock powder with either 50 or 90 wt% willow wood or 90 wt% wheat straw. Incubators featured two elevated soil pCO 2 levels (0.012 and 0.062 atm, equivalent to about 1.2 and 6.2 Vol-% CO 2 ) in a clay-rich, nutrient-poor Oxisol, with a simulated annual rainfall of 1,600 mm. Results showed strong initial fluxes of total alkalinity (TA), dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), and major cations (Mg 2+ , Ca 2+ , K + , Na + ), which decreased over time. Notably, elevated pCO 2 had minimal impact on the release of DOC but doubled the TA flux from ERW. An important observation was the impact of waterlogging on water fluxes in soil columns without biochar, which lowered the amount of leached cations from rock and biochar. We defined the carbon sink (C-Sink) to include all DIC of geogenic and biogenic origin, and pyrogenic carbon from biochar. Biogenic cations were not considered as contributing to additional CO 2 sequestration. For a soil a...