CO2-removal News

Peer-reviewed Publications

Nature – Alqahtani et al. (2025): Rapid CO2 mineralization by zeolite via cation exchange

Abdulwahab Alqahtani, Mouadh Addassi, Hussein Hoteit, Eric Oelkers IN: Scientific Reports, 15, https://doi.org/10.1038/s41598-024-82520-6

This study illuminates the mineral carbonation potential of zeolite minerals. Zeolite minerals are common alteration products of basaltic rocks and are known for their ability to rapidly exchange their interstitial cations with those in aqueous solutions. A series of closed system batch reactor experiments was conducted at 60 °C by combining stilbite, a Ca-bearing zeolite, with 0.1 mol/kgw aqueous sodium carbonate solutions. The individual batch reactor experiments ran from 2 to 225 days.

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Peer-reviewed Publications

Nature – Olim et al. (2025): Mitigating anthropogenic climate change with aqueous green energy

Sophia T. Olim, Anna Nickoloff, Leslie J. Moffat, Andrew J. Weaver, Michael Eby IN: Scientific Reports, 15, https://doi.org/10.1038/s41598-025-86042-7

The combination of direct air CO2 capture and storage (DACCS) and ocean thermal energy conversion (OTEC) allows for independently powered carbon capture plants to inject concentrated carbon into deep marine sediments where storage is generally safe and permanent. OTEC is a form of electricity production that exploits the temperature difference between deep and shallow ocean waters, and can power DACCS on floating platforms at a price competitive with coal-generated electricity. Here the authors highlight the scale of the challenge facing society.

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Peer-reviewed Publications

Nature – Barzegar & Feyzi (2025): Designing cellulose based biochars for CO2 separation using molecular simulations

Behnoush Barzegar, Farzaneh Feyzi IN: Scientific Reports, 15, https://doi.org/10.1038/s41598-025-86254-x

This study investigates the pyrolysis mechanism of cellulose using reactive molecular dynamics simulations to prepare biochars for CO2 separation applications. Six biochars with densities ranging from 0.160 to 0.987 g/cm³ were prepared, and their performance in adsorbing CO2, CH4, and N2 gases, as well as CO2/CH4 and CO2/N2 gas mixtures, was evaluated using Grand Canonical Monte Carlo (GCMC) simulations. The adsorption isotherms were fitted to the Dual-Site Langmuir (DSL) equation, and subsequently, the isosteric heat of adsorption, Gibbs free energy, and entropy changes were calculated.

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Peer-reviewed Publications

Science – Van Roijen et al. (2025): Building materials could store more than 16 billion tonnes of CO2 annually

Elisabeth Van Roijen, Sabbie A. Miller, and Steven J. Davis IN: Science, 387, https://www.science.org/doi/10.1126/science.adq8594

The quantity and relative longevity of structural materials used in the built environment could make them attractive for carbon dioxide removal. Although many of these materials are currently net carbon dioxide emitters, the authors outline how several of them could help lock up carbon for decades.

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Peer-reviewed Publications

Zhuang wt al. (2025): Potential Environmental Impacts and Management Strategies for Metal Release during Ocean Alkalinity Enhancement Using Olivine

Wen Zhuang, Tianqiang Zhu, Feng Li, Hermano Melo Queiroz, Qinglin Yan, Xiaojie Zhao, Jihua Liu IN: Environmental Science & Technology, 2025, https://doi.org/10.1021/acs.est.4c10705

Previous research primarily focuses on the toxicological effects of potentially toxic metals (PTMs) released from enhanced weathering of olivine (EWO). In this Perspective, the authors explore the overlooked impacts of EWO on environmental media in two scenarios: olivine applied to beaches/shallow continental shelves and offshore dispersion by vessels. They analyze the potential migration pathways of iron and PTMs (e.g., nickel and chromium) after their release, and their interactions with manganese oxides in sediments, potentially causing secondary contamination. Additionally, they propose mitigation strategies to prevent PTM concentrations from exceeding local environmental quality standards, including the use of alkalization equipment to control PTM levels.

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Peer-reviewed Publications

Suessle et al. (2025): Particle fluxes by subtropical pelagic communities under ocean alkalinity enhancement

Philipp Suessle, Jan Taucher, Silvan Urs Goldenberg, Moritz Baumann, Kristian Spilling, Andrea Noche-Ferreira, Mari Vanharanta, Ulf Riebesell IN: Biogeosciences, 22, https://doi.org/10.5194/bg-22-71-2025

By changing the carbonate speciation in seawater, Ocean alkalinity enhancement (OAE) may potentially alter marine ecosystems with implications for the biological carbon pump. Using mesocosms in the subtropical North Atlantic, the authors provide first empirical insights into impacts of carbonate-based OAE on the vertical flux and attenuation of sinking particles in an oligotrophic plankton community. They enhanced total alkalinity (TA) in increments of 300 µmol kg−1, reaching up to ΔTA = 2400 µmol kg−1 compared to ambient TA. They applied a pCO2-equilibrated OAE approach; i.e., dissolved inorganic carbon (DIC) was raised simultaneously with TA to maintain seawater pCO2 in equilibrium with the atmosphere, thereby keeping perturbations of seawater carbonate chemistry moderate.

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Peer-reviewed Publications

Snaie et al. (2025): Evaluating the two-pool decay model for biochar carbon permanence

Hamed Sanei, Henrik Ingermann Petersen, David Chiaramonti, Ondrej Masek IN: Biochar, 7, ttps://doi.org/10.1007/s42773-024-00408-0

Accurate estimation of biochar carbon permanence is essential for assessing its effectiveness as a carbon dioxide removal (CDR) strategy. The widely adopted framework, based on the two-pool carbon exponential decay model, forms the basis of policy guidelines and national CDR accounting. However, teh authors re-analysis of the meta-data used in this model reveals significant deficiencies in its parameterization, leading to two critical issues.

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Peer-reviewed Publications

Zhang et al. (2024): Enhanced Rock Weathering as a Source of Metals to Promote Methanogenesis and Counteract CO2 Sequestration

Donglei Zhang, Qiang Zeng, Hongyu Chen, Dongyi Guo, Gaoyuan Li, Hailiang Dong IN: Environmental Science & Technology, 2024, https://doi.org/10.1021/acs.est.4c04751

Enhanced weathering of (ultra)mafic rocks has been proposed as a promising approach to sequester atmospheric CO2 and mitigate climate change. However, these silicate rocks contain varying amounts of trace metals, which are essential cofactors of metallaenzymes in methanogens. We found that weathering of crushed peridotite and basalt significantly promoted the growth and methanogenesis of a model methanogen─Methanosarcina acetivorans C2A under the condition of excess substrate. The released trace metals from peridotite and basalt, especially Fe, Ni, and Co, accounted for the promotion effect. Observation at different spatial scales showed a close association between the rocks and cells. Proteomic analysis revealed that rock amendment significantly enhanced the expression of core metalloenzymes in the methylotrophic methanogenesis pathway. Our study uncovers a previously unrecognized but important negative effect of enhanced rock weathering on methane production, which may counteract the carbon sequestration effort.

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Peer-reviewed Publications

Nature – Zhou et al., (2025): Contributions of countries without a carbon neutrality target to limit global warming

Jiaxin Zhou, Wei Li, Philippe Ciais, Thomas Gasser, Jingmeng Wang, Zhao Li, Lei Zhu, Mengjie Han, Jiaying He, Minxuan Sun, Li Liu, Xiaomeng Huang IN: Nature Communications, 16,  https://doi.org/10.1038/s41467-024-55720-x

Some countries have made no commitment to carbon neutrality but are viewed as potential Bioenergy with carbon capture and storage (BECCS) candidates (hereafter, non-CN countries). Here the authors analyze contributions of these countries to global climate mitigation with respect to BECCS using an Earth system model with explicit representations of bioenergy crops.

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Peer-reviewed Publications

Nature – Li et al. (2025): Maximum carbon uptake potential through progressive management of plantation forests in Guangdong Province, China

Xueyan Li, Chongyuan Bi, Jianping Wu, Chaoqun Zhang, Wenting Yan, Zhenzhen Xiao, Ying-Ping Wang, Jiashun Ren, Yongxian Su IN: Communications Earth & Environment, 6, https://doi.org/10.1038/s43247-024-01977-5

Forest cover in Guangdong Province, southern China, has doubled over the last four decades. A large proportion of these forests consists of young planted forests (PFs), which have significant potential as carbon sinks. Yet given the declining carbon accumulation rates as forests mature and limited land for further planting, how best to manage these forests to maximize their future carbon uptake remains poorly studied. Here the authors employed fine-resolution satellite data, forest growth models, and machine learning to identify key drivers of carbon accumulation. They further assessed the carbon sink potential under five forest management scenarios, each involving different harvest and regeneration strategies.

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