This week’s publication highlights relate to direct air capture, carbon sequestration in terrestrial ecosystems, biochar carbon removal and ocean alkalinity enhancement.
Bifunctional Na-Ru on Gamma-Alumina for CO2 Capture from Air and Conversion to CH4: Impact of the Regeneration Methods and Support on Monolithic Contactors
Abstract
Dual functional materials (DFMs) have the potential to improve the process of CO2 capture and subsequent conversion to fuel. Materials consisting of Na and Ru supported on alumina have been investigated for cyclic direct CO2 air capture and conversion to CH4. We have studied the regeneration conditions, specifically the target temperature and gas composition (inert or hydrogen-containing gas) during heating. The effect of air humidity and Na loading on the effectiveness of CO2 capture has also been assessed. Finally, the DFMs have been successfully implemented as structured contactors with a low pressure drop, which is an unavoidable requirement for practical application.
Bordeje, E. et al. (2025) Biofunctional Na-Ru on Gamma-Alumina for CO2 Capture from Air and Conversion to CH4: Impact on the Regeneration Method and Support on Monolithic Contractors 4 Industrial Chemistry and Materials.
Read the full paper here: Biofunctional Na-Ru on Gamma-Alumina for CO2 Capture from Air and Conversion to CH4: Impact on the Regeneration Method and Support on Monolithic Contractors I Industrial Chemistry and Materials.
Emerging 2D-Ti3C2TX-MXene Nanomaterial Anchored on MIL-101(Cr) Metal-Organic Framework as Solid Adsorbent for CO2 Capture under Ambient Conditions
Abstract
The increasing accumulation of CO2 in the atmosphere has intensified the need for efficient carbon dioxide capture materials. However, it is a challenge to come up with an optimum solid CO2 adsorbent that can substitute chemical adsorption for large-scale applications. Among various solid sorbents, metal-organic frameworks (MOFs) combined with newly emerging two-dimensional (2D) nanomaterials, Ti3C2Tx-MXene, have attracted significant attention owing to their higher porosity, tunable structures, and large surface areas and physisorption mechanism. In this study, we describe the utilization of 2D Ti3C2Tx-MXene anchored on MIL-101(Cr) MOF in solid form to evaluate their CO2 adsorption performance using a fixed-bed adsorption column. Advanced characterization of the as-produced adsorbent is conducted using XRD, FTIR, SEM with EDS, TGA, and BET analysis to assess their surface morphology, surface groups, chemical composition, and surface properties. The synthesized composite showed a BET surface area of 2138 m2/g and a pore volume of ∼1.34 cm3/g. In the adsorption column, CO2 breakthrough measurements were performed by a continuous CO2 concentration (15 %) with an inlet flow of 40 mL/min at 1 atm and 25 °C. The CO2 adsorption capacity (∼21 mg/g) was achieved by Ti3C2Tx-MXene/MIL-101 (Cr) at ambient conditions. This corresponds to ∼50 % better performance than pristine MIL-101 (Cr) at similar conditions. Moreover, the Ti3C2Tx-MXene/MIL-101 (Cr) offers good regeneration performance with no significant loss in CO2 adsorption capacity in regenerative cycles. Finally, the novel work with good CO2 adsorption results opens a new window of implications of emerging nanomaterials as a promising material platform for CO2 capture applications for further investigation under direct air capture conditions (ultra-low CO2 concentrations).
Shoukat, S. et al. (2026) Emerging 2D-Ti3C2TX-MXene Nanomaterial Anchored on MIL-101(Cr) Metal-Organic Framework as Solid Adsorbent for CO2 Capture under Ambient Conditions 104 (103322) Journal of CO2 Utilization.
Read the full paper here: Emerging 2D-Ti3C2TX-MXene Nanomaterial Anchored on MIL-101(Cr) Metal-Organic Framework as Solid Adsorbent for CO2 Capture under Ambient Conditions I Journal of CO2 Utilization.
Theoretical and Actual Carbon Sequestration Potential in China’s Terrestrial Ecosystems
Abstract
Terrestrial ecosystems are vital for achieving carbon neutrality, yet the distinction between their biophysical limits and realizable potential remains unclear. Here, we developed an integrated framework to quantify China’s terrestrial theoretical carbon sequestration potential (CSP) and actual CSP under diverse climate and management scenarios, incorporating vegetation dynamics and soil carbon stocks through 2100. We estimated current terrestrial carbon stock at 95.3 Pg C, with a theoretical CSP of 166.4 Pg C. By the 2060s, afforestation could expand by 77.5 Mha, representing 8% of China’s land area. For actual CSP, peak CSP is projected to reach 0.35 Pg C yr−1 during 2020–2060, declining to 0.12 Pg C yr−1 from 2060 to 2100 under the SSP119 scenario combined with forest expansion. Actual CSP remains significantly below the theoretical limit. Specifically, a gap of 51.5–57.9 Pg C remains between actual and theoretical CSP across all scenarios. However, strategic reforestation coupled with low emissions could reduce this gap by approximately 15 Pg C by 2100. These findings differentiated the theoretical and actual CSP, providing quantitative baselines for China’s carbon sink capacity and actionable guidance for achieving carbon neutrality through optimized land use.
Wang, X. et al. (2026) Theoretical and Actual Carbon Sequestration Potential in China’s Terrestrial Ecosystems 32(3) Global Change Biology.
Read the full paper here: Theoretical and Actual Carbon Sequestration Potential in China’s Terrestrial Ecosystems I Global Change Biology.
Beyond One-Size-Fits-All: Tailoring Engineered Biochar for Purpose-Specific Rhizosphere Engineering in Crop Production, Protection, and Soil Remediation
Abstract
Engineered biochar has emerged as a versatile tool for purpose-specific rhizosphere engineering, offering tailored solutions for enhancing crop production, crop protection, and environmental remediation. Yet, its effectiveness depends on optimizing application for specific functional goals rather than adopting a one-size-fits-all approach. This review explores how engineered biochar shapes rhizosphere processes to support crop production, crop protection, and soil remediation. It examines key mechanisms including enhanced nutrient availability, stimulation of beneficial microbial communities, pathogen suppression, and soil contaminant immobilization, and how different biochar modifications, such as nutrient enrichment, antimicrobial functionalization, and surface engineering, drive these outcomes. The review highlights important trade-offs, such as the competing demands of nutrient availability for crop growth versus contaminant immobilization for remediation, and accounts for the spatial and temporal variability of biochar effects in the rhizosphere. While biochar presents clear synergistic benefits (e.g., improving soil structure, enhancing water retention, reducing greenhouse gas emissions, and enabling carbon sequestration), its practical application faces challenges related to competing objectives, rhizosphere complexity, and economic constraints. Emerging innovations such as nanocomposite biochars, bioprimed biochars, and biochar-microbe synergies offer new avenues for precision agriculture and sustainable land management. Finally, the review emphasizes the importance of long-term field studies to evaluate sustainability, and outlines opportunities for biochar in climate change mitigation, waste valorization, and agroecological resilience. By integrating the latest research on biochar’s mechanisms, challenges, and opportunities, this review provides a comprehensive framework for leveraging engineered biochar to address the pressing challenges of modern agriculture and environmental management.
Mustafa, A. et al. (2026) Beyond One-Size-Fits-All: Tailoring Engineered Biochar for Purpose-Specific Rhizosphere Engineering in Crop Production, Protection, and Soil Remediation 8(3) Biochar.
Read the full paper here: Beyond One-Size-Fits-All: Tailoring Engineered Biochar for Purpose-Specific Rhizosphere Engineering in Crop Production, Protection, and Soil Remediation I Biochar.
Hybrid-Energy-Powered Electrochemical Ocean Alkalinity Enhancement Model: Plant Operation, Cost, and Profitability
Abstract
Electrochemical ocean alkalinity enhancement is a form of marine carbon dioxide removal, a rapidly growing industry that is powered by efficient onshore or offshore energy sources. As more and larger deployments are being planned, it is important to consider how variable energy sources like tidal energy can impact plant performance and costs. An open-source Python-based generalizable model for electrodialysis-based ocean alkalinity enhancement has been developed that can capture key system-level insights of the electrochemistry, ocean chemistry, acid disposal, and co-product creation of these plants under various conditions. The model additionally accounts for hybrid energy system performance profiles and costs via the National Laboratory of the Rockies’ H2Integrate tool. The model was used to analyze an example theoretical plant deployment in North Admiralty Inlet, including how the plant is impacted by the available energy sources in the region and the scale at which plant costs are covered by the co-products it generates, such as recycled concrete aggregates, without requiring carbon credits. The results show that the example plant could be profitable without carbon credits at commercial scales of 100,000 to 1 million tons of carbon dioxide removal per year, so long as it uses low-cost electricity sources and either sells acid or recovers recycled concrete aggregates with about 1 molar acid concentrations, though more research is needed to confirm these results.
Niffenegger, J. S. et al. (2026) Hybrid-Energy-Powered Electrochemical Ocean Alkalinity Enhancement Model: Plant Operation, Cost, and Profitability 8(1) Clean Technologies.
Read the full paper here: Hybrid-Energy-Powered Electrochemical Ocean Alkalinity Enhancement Model: Plant Operation, Cost, and Profitability I Clean Technologies.