Tailoring the polarity of 13X zeolite with glycine for efficient capture of oxygenates from Fischer-Tropsch oil

One of the best ways to prevent further warming of the planet and reduce pollutants is to remove or adsorb and recover carbon dioxide gas from the exit of cement factory exhaust. So far, several methods have been proposed for this; In this research, zeolite 13X adsorbent is used considering the operational conditions. To remove CO2 gas from the desired gas mixture, an adsorption operation unit with a column filled with zeolite 13X adsorbent was simulated in Aspen Adsorption V14 software. Changes in parameters such as temperature, and pressure and their effects on adsorption rate, adsorbent saturation time, and output heat rate were investigated to achieve higher system efficiency and optimal operating conditions. The adsorption unit was optimized by RSM to achieve maximum CO2 adsorption. Temperature and mole fraction of CO2 were identified as key influencing factors determining the adsorption performance of zeolite 13X for CO2 adsorption. It was found that the system should be operated at a temperature of 28.07 °C and a pressure of 1.202 bar to achieve maximum adsorption. Finally, 2.784 mol% CO2 gas was captured by the said process in optimal operating conditions. Further analysis revealed higher temperatures slightly decrease CO2 adsorption capacity, while increasing pressure enhances it. Conversely, elevated flow rates reduce breakthrough time, indicating a trade-off between adsorption capacity and capture efficiency.

Microporous carbon coated zeolite particles for efficient carbon capture from wet flue gas

A model-based approach for the evaluation of new zeolite 13X-based adsorbents for the efficient post-combustion CO2 capture using P/VSA processes

This study investigates the regeneration of zeolite 13X for direct air CO2 capture by comparing microwave-assisted and conventional heating methods in a fixed-bed reactor. Zeolite 13X, a high-surface-area solid adsorbent, was tested over three adsorption/desorption cycles under ambient conditions with approximately 400 ppm of CO2. Microwave-assisted regeneration, optimized at 300 W for 10 min (350 °C), achieved a regeneration efficiency of 95.26%, with minimal loss in adsorption capacity (9%) across cycles. Conventional heating at 350 °C for 30 min achieved a comparable efficiency of 93.90% but required significantly more time and energy. The microwave technique operates via direct dielectric heating, selectively exciting polar species such as mobile Na⁺ ions within the zeolite framework. This localized and volumetric heating enhances CO2 desorption without requiring reactor preheating or carrier gas flow, unlike conventional methods that rely on slower conduction and convection. As a result, microwave regeneration demonstrated a tenfold reduction in energy consumption (0.06 kWh vs. 0.62 kWh for conventional heating). Statistical analysis using ANOVA identified microwave power and regeneration time as key factors, with microwave power exerting the greatest influence. The study highlights the advantages of microwave-assisted regeneration, including reduced energy demand, shorter regeneration times, and enhanced scalability. These findings emphasize its potential as a transformative approach for advancing direct air capture technologies. Compared to conventional methods, microwave-assisted regeneration offers a more energy-efficient and practical solution for CO2 removal from ambient air.

The search for methods to capture carbon dioxide (CO2) emissions from solid fuel combustion processes has led to the development and subsequent testing of alternative innovative CO2 capture technologies. Vacuum Pressure Swing Adsorption (VPSA) method is a promising technology for efficient CO2 capture using solid sorbents. This article introduces CO2 capture using the VPSA technology, providing description of the selected VPSA method and the construction of a pilot-scale unit for VPSA CO2 capture. The main goal of this article is to present experimental results, including a description of the pilot-scale unit used for the VPSA adsorption tests using zeolite 13X, an industrially proven sorbent for CO2 capture. The measured adsorption values were compared with theoretical isotherms, allowing the assessment of VPSA method efficiency and accuracy in practical conditions. Results indicated discrepancies between the experimental unit and the theoretical adsorption models, attributed to non-ideal conditions, non-optimised processes, incomplete drying of the sorbent, and temperature variations affecting the adsorption efficiency. The conclusion confirms the VPSA lab unit’s ability to adsorb CO2 using solid sorbents, suggesting that further research and additional tests with new alternative sorbents is needed.

Integration of adsorption based post-combustion carbon dioxide capture for a natural gas-fired combined heat and power plant

This paper deals with gas separation by adsorption processes. The key objective is to investigate the adsorption suitability for Post-combustion Carbon Dioxide (CO2) Capture (PCC). Adsorption is a promising technology suitable for a high volume of diluted gas processing. Unlike commercialised amine-based absorption processes, adsorption seems to require less energy for sorbent regeneration and extends the sorbent lifetime. Two common industrial methods utilizing a difference in adsorption equilibrium of the gas components were investigated: 1) Pressure Swing Adsorption (PSA) including Vacuum Swing Adsorption (VSA), 2) Temperature Swing Adsorption (TSA). A comparison of their energy consumption, suitability for industrial use with consideration of Carbon Capture and Storage standards is evaluated. A complex mathematical model for the adsorption step of the fixed bed adsorber was proposed and solved by the structural programming. Three adsorbent materials: Mg-MOF-74, UTSA-16, and Zeolite 13X were evaluated based on their CO2 adsorption capacity, selectivity, and market availability. Zeolite 13X was further explored. As a benchmark case, a medium-sized natural gas cogeneration unit was used to study the potential of VSA unit. The lower limit of CO2 capture efficiency in simulations was 75 %. The results presented in this paper suggest that adsorption can be a feasible CO2 capture solution for a low-carbon emission power generation technologies. Optimal parameters for the adsorption step and column configuration are proposed.

Porous polymer gels (PPGs) are characterized by inherent porosity, a predictable structure, and tunable functionality, which makes them promising for the heavy metal ion trap in environmental remediation. However, their real-world application is obstructed by the balance between performance and economy in material preparation. Development of an efficient and cost-effective approach to produce PPGs with task-specific functionality remains a significant challenge. Here, a two-step strategy to fabricate amine-enriched PPGs, NUT-21-TETA (NUT means Nanjing Tech University, TETA indicates triethylenetetramine), is reported for the first time. The NUT-21-TETA was synthesized through a simple nucleophilic substitution using two readily available and low-cost monomers, mesitylene and α, α′-dichloro-p-xylene, followed by the successful post-synthetic amine functionalization. The obtained NUT-21-TETA demonstrates an extremely high Pb2+ capacity from aqueous solution. The maximum Pb2+ capacity, qm, assessed by the Langmuir model was as high as 1211 mg/g, which is much higher than most benchmark adsorbents including ZIF-8 (1120 mg/g), FGO (842 mg/g), 732-CR resin (397 mg/g), Zeolite 13X (541 mg/g), and AC (58 mg/g). The NUT-21-TETA can be regenerated easily and recycled five times without a noticeable decrease of adsorption capacity. The excellent Pb2+ uptake and perfect reusability, in combination with a low synthesis cost, gives the NUT-21-TETA a strong potential for heavy metal ion removal.

In-situ SIFSIX-3-Cu growth into melamine formaldehyde sponge monolith for CO2 efficient capture

Ammonia is a carbon-free energy carrier and a natural refrigerant with a high energy density. However, its high toxicity raises significant safety concerns in confined environments. To address this issue, this study developed a hybrid ammonia capture material, water-loaded zeolite 13X (WLZ), which combines the structural stability of zeolites with a strong chemical affinity for water. WLZ was synthesized using an ethanol-water impregnation method. A series of experiments were conducted under simulated leak conditions in pure ammonia and air. WLZ-75, containing 75% water loading, demonstrated high ammonia capture efficiency (over 90% removal at 1000 ppm), stable low-temperature regeneration below 90 °C over repeated cycles, and more than 95% retention after 10 capture/regeneration cycles. Chamber-scale tests confirmed not only its high removal performance but also exothermic behavior, potentially enabling thermal-based leak detection. These results demonstrate that WLZ is a highly regenerable and thermally responsive material suitable for ammonia safety management in refrigeration, fuel systems, and sealed environments.