Synthesizing high-performance zeolite X from coal gangue for flue gas CO2 capture

Hot-climate flue-gas CO2 algal treatment of undiluted swine wastewater: Field-validated performance and operating rules

The utilization of metal carbonates to produce directly valuable carbon feedstocks remains a major challenge, particularly under mild operating conditions. Herein, we report the elusive conversion of inorganic metal carbonates, such as sodium and potassium carbonates, to methanol in a one-step process with molecular hydrogen over a heterogeneous Cu/ZnO/Al2O3 catalyst. The hydrogenation occurs effectively at a relatively mild temperature of 200°C and proceeds in presence of ethylene glycol in the liquid phase with methanol yields of up to 95%. Alkali carbonates/bicarbonate salts obtained by capturing CO2 from ambient air (Direct Air Capture, DAC) and flue gas CO2 with aqueous alkali media also undergo facile hydrogenation to methanol.

Simulation and Integration Optimization of Energy-Saving Processes for Flue Gas CO2 Capture System in Coal-Fired Power Plants Based on MEA/AMP Blended Solvent

Asymmetric Co-Ov-Ti in hierarchical platelet-spherical structure Co NCs/Ti3C2 MXene for simultaneous and competitive catalytic oxidation of Hg0 and CO in flue gas

The equipment required for large-scale production of quality microalgal biomass is costly to set-up. To address this challenge a novel low-cost internally illuminated reactor ‘the Cube’ has been developed, which is suitable for deployment in high latitude countries with low natural light conditions. This innovative concept combines the use of low-cost materials, LED lighting, effective temperature and pH control technology to produce high quality algal biomass from industrial CO 2 effluent at low initial capital cost. This study evaluated the ability of the cube by growing Arthrospira platensis (Spirulina). The reactor achieved biomass concentrations of 1.37 g L -1 and 80.5 mg L -1 day -1 productivity in a 1 m 3 volume that occupies 1 m 2 , with consistent productivity spanning 78 days, surpassing some of the existing most cost-effective microalgae cultivation system designs currently available. Aerial productivity was demonstrated as 92.1 kg year -1 m -2 compared to 4.2 kg year -1 m -2 for a comparable raceway. Protein composition was 54.1% and phycocyanin content was 78.27 mg g -1 of biomass. An economic appraisal gave capital cost as £12,776.60 per m 3 reactor and potential profits from pigment and protein production lead to a payback period of only 1.7 years. This novel reactor demonstrates sustainable profits from carbon capture and reuse.

The preparation of α-alkylidene cyclic carbonates through a cyclization reaction of propargylic alcohols with CO2 is important in the industrial process. Herein, a novel mixed-valence heterometallic Cu/Eu-based cationic framework, 1-Eu, was successfully synthesized. The material features a unique 14 Å nanocage structure and was effectively employed in the catalytic conversion of propargylic alcohols with CO2. 1-Eu exhibits remarkable stability in various solvents as well as under acidic and basic conditions, and can maintain the framework stability even in the presence of the strong organic base DBU. Catalytic evaluations demonstrate that 1-Eu can efficiently promote the conversion of propargyl alcohol and CO2 to α-alkylidene cyclic carbonates under mild conditions. Furthermore, it demonstrates high catalytic activity in the conversion of the biomacromolecule norethindrone with CO2. Notably, even when low-concentration CO2 in simulated flue gas is used as the carbon source, 1-Eu remains highly effective in catalyzing the conversion of propargyl alcohol substrates to the corresponding α-alkylidene cyclic carbonate products. The results of the control experiment show that the synergistic catalytic effect between CuI/CuII and EuIII plays a crucial role in the activation of CO2 and propargyl alcohol, thereby facilitating the catalytic reaction.

Metal-organic frameworks (MOFs) exhibit attractive catalytic performance, particularly for carbon dioxide (CO2) fixation. We here developed a new MOF {Cu2(Bibt)(Apta)2}n, namely CuBA, under the solvothermal process {Bibt = (4,7-bis(1H-imidazol-1-yl)benzo-[2,1,3]thiadiazole, Apta = deprotonation of 2-aminophthalic acid}. CuBA forms a paddle-wheel binuclear copper(II) Cu2(COO)4N2 unit, which is further extended to a 6-connected three-dimensional (3D) {412•63} topology. In particular, CuBA shows a high CO2/N2 selectivity at 298 K, which encourages us to apply it to catalyze CO2 fixation. The experiments demonstrate that CuBA can catalyze the carboxylative cyclization of various propargylic amines with CO2 at ambient conditions (1 atm, 25 °C) with high TON. Moreover, CuBA maintains good catalytic activities for 5 cycles, showing good recyclability. Significantly, the gram-scale reaction is performed with a good yield. Furthermore, the low-concentration CO2 (30 vol %) experiments under CuBA afford the products in moderate to good yields (25 °C, 24 h). 1H NMR studies indicate that CuBA and DBU work together to activate the propargylic amine substrate, facilitating the reaction. It is anticipated that this work will inspire the rational design of non-noble-metal-containing MOFs for efficient CO2 utilization under mild conditions.

An efficient carbon capture and release system necessitates rapid CO2 transport to and from active sites, a property typically associated with permanently porous materials featuring large surface areas. Here, we present hydrophobic organic crystals of alkylated monoethanolamine that, despite their nonporous nature, undergo a rapid and reversible solid-to-solid phase transition upon CO₂ uptake and release. Exposure to CO2 triggers a thermodynamically favored structural rearrangement, enabling quantitative CO2 capture and forming a stable carbamate, aided by intermolecular interactions involving the long side chains. This process is fully reversible under practical flue-gas CO2 capture conditions (>0.6% CO2, 0-100% relative humidity) and enables low-temperature desorption using CO2 itself as a stripping gas (65 °C at 1 atm CO2). Structural analysis through in situ XRPD, solid-state NMR spectroscopy, electron diffraction, and Raman analysis confirms that these hydrophobic absorbents selectively uptake CO2 to form an anhydrous ammonium carbamate pair in the solid state. The non-hygroscopic nature of these organic crystals is exemplified by a representative C10-MEA in the presence of CO2, resulting in a desorption process with a minimal temperature swing (ΔTabs-des = 30 °C), offering an energy-efficient (>1.2 GJ/t of captured CO₂) and economically viable alternative for carbon capture applications.

Effect of SO2 on Na2ZrO3 sorbent for CO2 capture: An experimental and density functional theory study.

Economic optimization of naphtha pyrolysis furnaces with an integrated chamber–coil model: Profit–emissions trade-offs under carbon pricing

The electroreduction of low-concentration carbon dioxide to ethylene is highly attractive, as it enables the utilization of dilute CO₂ in flue gas while producing high-value-added chemicals. However, the inherent difficulty...

This study investigates high-light-tolerant Nannochloropsis oceanica Rose Bengal mutants (RB2 and RB113) for bioremediation of shrimp aquaculture wastewater (SWW) under increased temperature and light, simulating future climate change. Cultivations were performed under 250μmol photonsm-2·s-1 with flue gas CO₂ supply. At 18°C, RB mutants and wild-type (WT) strain showed similar growth. At 25°C, representative of warming in subtropical and temperate regions, the RB113 mutant outperformed WT and RB2 in terms of biomass accumulation, photosynthetic efficiency, and non-photochemical quenching. Temperature-dependent nutrient removal patterns revealed that while WT effectively removed inorganic nitrogen and phosphorus, RB113 prioritized biomass and lipid production, highlighting a trade-off between remediation and bioresource accumulation. CO₂ capture was estimated at its highest at 25°C in RB113 (381 tons CO₂ ha/year). On day 2, under initial nitrogen starvation, RB113 produced 9.95mg/g DW of eicosapentaenoic acid (EPA) with a peak productivity of 2.338mg/L/day. By day 5, prolonged nitrogen depletion caused EPA to decline to 3.57mg/g DW, while total fatty acids doubled to 63mg/g DW, with a dominance of saturated forms, indicating a shift toward storage lipids. These results suggest that RB113 has significant potential as a climate-adapted bioresource, capable of integrating wastewater remediation, carbon capture, and high-value EPA production, without the need for low-temperature induction. As global temperatures rise and aquaculture expands, this climate-resilient method offers sustainable inland marine aquaculture management by reducing nutrient pollution, with additional benefits of mitigating greenhouse gases and transforming wastewater into valuable products.

Lignin-based hyper-crosslinked polymers with abundant ionic sites for effective conversion of CO2 in simulated flue gas.

Preparation of low-cost hierarchical porous cellulose aerogels and their adsorption performance for pure CO2 and CO2 in the simulated cement plant flue gas

Integrated flue gas desulfurization and CO<span class="sub">2</span> mineralization technology at Anhui Conch

Microalgae-mediated treatment of steel industry reverse osmosis concentrate integrated with flue gas carbon fixation: From laboratory selection to pilot-scale verification.

Efficient transformation of flue gas CO2 is of great significance, but it remains a formidable challenge. Herein, we constructed four isostructural metal-organic frameworks (MOFs) with anionic frameworks, including a homometallic Mn-MOF and three heterometallic MOFs: Mn/Co-MOF, Mn/Ce-MOF, and Mn/Eu-MOF. All of these MOFs exhibited unsatisfactory activity in the catalytic carboxylative cyclization of propargylic amines with CO2. To overcome this limitation, Cu2+ was introduced into Mn-MOF via a cation exchange strategy, yielding composite Cu2+-Mn-MOF. Remarkably, Cu2+-Mn-MOF not only catalyzed the carboxylative cyclization of propargylic amines with pure CO2 but also enabled the reaction using flue gas CO2 to afford oxazolidinone products. The catalyst retained high activity and stability over five successive cycles. Control experiments and density functional theory (DFT) calculations revealed that Cu2+ interacted with the uncoordinated -NH2 groups in the channels and that the synergistic effect between Cu2+ and the Mn-MOF strongly activated both the amino and alkynyl groups of the substrate, thereby facilitating the catalysis. This work presents the first detailed investigation of metal-node doping and Cu2+ incorporation in Mn-based MOFs for the catalytic conversion of flue gas CO2.

Capturing CO2 from flue gas and converting it electrochemically into valuable chemicals represents an appealing approach to mitigate CO2 emissions and realize carbon recycling. Currently, these two processes are usually performed sequentially, which is energy-intensive and involves multiple operational steps. Here, a simultaneous route is reported for capturing and electrochemically converting CO2 from flue gas without interruption, mediated by bicarbonate electrolysis. The electrochemical conversion of bicarbonate solution, catalyzed by a Ni single-atom catalyst, is unaffected by O2 and residual NO and SO2 impurities, commonly found in flue gas. This enables the simultaneous capture and conversion of CO2 from flue gas into CO without the need to remove these gas components. Mechanistic studies reveal that CO2 from flue gas is first captured by basified electrolyte and then electrochemically converted. The simultaneous system operates stably for at least 120h, achieving a CO2 capture and utilization efficiency of 60%, producing >20000mL of syngas with a H2/CO ratio of ≈3, and reducing energy consumption by 25% compared to the sequential route. This simultaneous route exhibits significant advantages, including simplified operation, enhanced stability, and reduced energy consumption, thereby opening a promising avenue for direct valorization of diluted CO2 in flue gas.

Nitrate modulates high CO2 effects on carbon partitioning in Gracilariopsis lemaneiformis: Trade-offs between particulate and dissolved organic carbon sequestration.