The global energy supply still largely relies on fossil fuels, whose combustion releases significant amounts of carbon dioxide (CO2), the primary anthropogenic greenhouse gas linked to climate change. Adsorption on solid porous materials offers a promising alternative to conventional amine-based systems for CO2 capture from industrial flue gases. While various materials, including zeolites and metal-organic frameworks (MOFs), have been extensively studied for high-concentration CO2 streams, post-combustion capture at low concentrations (below 5% CO2) under realistic conditions with water vapor remains poorly explored. Material selection requires balancing CO2 adsorption capacity against water affinity, as strong hydrophilicity deteriorates regeneration efficiency. The challenge is to identify scalable, environmentally friendly materials that maintain high CO2 selectivity under realistic flue gas conditions containing both low CO2 concentrations and significant water vapor. Here, we show that CALF-20, a scalable MOF, exhibits superior CO2 adsorption selectivity and regenerability compared to other tested materials, both in dry and humid conditions. Under dynamic breakthrough conditions using 2.5% CO2 and 50% relative humidity, CALF-20 maintained a high CO2 uptake (1.49 mmol g-1) consistent with static isotherm data, and demonstrated complete regenerability at 80 °C without loss of performance over multiple cycles. These results directly contrast with hydrophilic zeolites, which, despite high raw CO2 capacities, are unsuitable under realistic, humid flue gas. Our results under industrially relevant post-combustion conditions demonstrate that low water affinity combined with moderate CO2 capacity outperforms high-capacity hydrophilic materials. This approach represents an effective pathway for CO2 capture under realistic conditions and provides valuable insights for the development of selective, robust, and scalable CO2 adsorbents. Such developments are expected to contribute significantly to reducing atmospheric CO2 emissions and addressing climate change mitigation targets in the coming years.

Volatile organic compounds (VOCs) are ubiquitous air pollutants arising from industrial, vehicular, and household sources, which present significant risks to both environmental quality and human health. Advances in air purification increasingly rely on high-performing adsorbents for VOC removal, with material innovations in microporous and mesoporous frameworks driving the field toward more efficient and selective remediation methods. However, accurately characterizing adsorbent affinity for VOCs at trace levels remains challenging due to extremely slow adsorption kinetics in highly confining ultramicroporous solids. In this context, accurately determining the Henry constant K H for VOC adsorption in microporous solids at low pressures is limited by difficulties in reaching thermodynamic equilibrium in standard experimental methods. Here, a thermodynamically grounded three-step methodology is introduced for reliable estimation of the Henry constant in such diffusion-limited systems. In practice, this strategy is illustrated by considering cyclohexane adsorption on commercial activated carbon. The approach involves (1) measuring adsorption isotherms at elevated temperatures (which ensure that thermodynamic equilibrium is reached), (2) extrapolating to the target temperature via Polanyi’s adsorption potential theory, and (3) finally deriving K H from the recalculated low-pressure region. Compared to conventional single-temperature volumetric measurements — where equilibrium is hardly attained at low pressure — this method allows reconstructing the adsorption isotherm. This strategy, which is validated by showing that the adsorption isotherms match those obtained from independent breakthrough experiments, reveals systematic underestimation of adsorption at low pressure with standard protocols (up to a 15-fold difference in K H ). This study demonstrates how corrections based on Polanyi’s adsorption potential theory allow overcoming equilibrium limitations, outperforming both measurements and kinetic-based protocols alone. In contrast to previous assumptions that improved measurement criteria or longer equilibration times suffice, our findings emphasize that thermodynamic equilibrium can only be ensured by relying on high-temperature master curves for systematic recalculation. By providing accurate K H values, which are critical for materials screening and process upscaling, this framework enables more robust engineering of sorbent-based air purification technologies. This methodological advance has broad implications for experimental practice in nanostructured adsorbent evaluation and supports safer, more efficient approaches to air pollution control.

Efficient utilization of low-grade waste heat is key to reducing the carbon footprint of cooling and water-harvesting technologies. Adsorption-based devices employing porous materials enable thermally driven heat exchange and atmospheric water capture with low environmental impact. While zeotype materials such as SAPO-34 (commercially known as FAM-Z02) have long been benchmarks in these systems due to their stability and appropriate water uptake behavior, their relatively high synthesis cost still limits their commercial deployment. This study addresses the need for alternative sorbents capable of achieving high water working capacities at lower regeneration temperatures under realistic heat-pump and water-harvesting conditions. This study demonstrates, for the first time, a scalable, water-based synthesis of MIL-160, enabling production at industrially relevant scales for adsorption heat transformation and water harvesting. We show that MIL-160 exhibits a high water uptake (434 g kg-1 at 20 °C), a 15-70% increase in working capacity over the industrial benchmark FAM-Z02, and, critically, an efficient regeneration at only 60 °C, corresponding to the temperature range of typical waste heat. This low-temperature desorption behavior translates directly into enhanced energy efficiency and reduced operational costs for adsorption-based cooling and water-harvesting systems, while the material maintains excellent hydrothermal and cyclic stability. This efficient low-temperature regeneration highlights MIL-160s strong potential for energy-saving thermal management and adsorption-based cooling systems. By bridging the gap between laboratory-scale MOFs and industrially viable sorbents, this study advances the practical implementation of next-generation, low-carbon thermal management technologies.

We report a molecular simulation study on the adsorption-based trapping of different gaseous contaminants using nanoporous materials. In more detail, in the context of gas decontamination for space applications, we focus on adsorption from low pressures up to larger pressures of specific molecules ranging from water, hydrocarbons, and siloxanes. As far as the nanoporous adsorbents are concerned, we restrict the present study to a set of prototypical materials: an active carbon, a zeolite and a metal-organic framework. In addition to discussing the ability of each material type to adsorb specific gas molecules, we illustrate how simple descriptors such as Henry’s constant in the low-pressure range K_H and the pressure α at which half the nanoporosity gets filled can be used to rationalize and design molecular “getters” for space decontamination. Finally, by considering a specific yet representative binary gas mixture, we show that the adsorption of hydrophilic molecules– water– and hydrophobic molecules– siloxane– occurs without competitive/collective adsorption effect (provided adsorption occurs at low to moderate pressures).

Water adsorption on Aluminium Fumarate (Al-Fum), a promising MOF for low-temperature heat-driven applications, exhibits complex isotherm shapes that challenge conventional modeling approaches. In this work, we develop a physically grounded dual-site adsorption model that combines Langmuir adsorption on high-energy sites with cooperative water clustering based on association theory. The model reproduces full isotherm profiles across a broad temperature range (20–90 °C) using eight temperature-independent parameters with clear physical significance. The model achieves excellent agreement (adjusted R² = 0.9957), accurately capturing both low-pressure concavity and the S-shaped transition. It also enables the calculation of isosteres and isosteric heats of adsorption, revealing distinct thermodynamic regimes governed by the two adsorption mechanisms. To demonstrate system-level relevance, the model is applied to a typical intermittent adsorption cooling cycle operating at 10/30/60°C. Al-Fum delivers a thermal COP of 0.785 (excluding heat exchangers’ sensible heat) and a cycled mass of 177.5 g kg⁻¹, outperforming benchmark materials. This work provides a robust, physically sound modeling tool for the design and optimization of advanced adsorption-based thermal systems.

This study presents a spray-drying Al-fumarate synthesis that allows simultaneous synthesis and workup. This all-in-one step synthesis produces calibrated Al-fumarate grains of high quality without the need for further processing. Obtained materials are characterized by PXRD, TGA, N2 and H2O adsorption, PSD, and microscopy imaging. The synthesis has been upscaled to the 60 kg scale. Whereas all reported synthesis routes in the aqueous phase proceed in base conditions by addition of NaOH, the synthesis reported herein is obtained at a pH below 3, with aluminum isopropoxide acting as a base that can steadily react with fumaric acid without the need for pH adjustment. Major differences in the large meso- to macroporous structure are observed depending on the drying process, with an absence of intergranular porosity for the spray-dried pilot batch, reflecting the high-density nature of the obtained MOF powder. Large productivity can be achieved at spray-driers due to their important evaporation capacity (up to several hundreds of tons of/h), opening the perspectives of mass production of Al-fumarate. Air dehumidification in a fluidized bed is carried out as a proof-of-concept application. The fluidized bed's breakthrough curve profile, with a longer t50%, is in line with a better column isothermicity, connected to the fluidization conditions. Ultimately, we developed a comprehensive 3-in-1 process that integrates synthesis, drying, and shaping while also exploring its potential for production intensification. We believe that this synthesis approach could pave the way for the scalable production of other Al-MOFs, a topic currently under investigation.

Technological innovations allowing the capture of volatile organic compounds (VOCs), in particular aromatic compounds (BTEX), continue to be sought. Activated carbon (AC) is a widely-used adsorbent, but upon moderate temperature increases, typically 50 degrees C, it tends to release accumulated VOCs and thereby contribute to air pollution peaks. We evaluate herein the adsorption performances of ZIF-7 synthesized from a new and greener protocol as well as ZIF-8. These two MOFs exhibit flexibility triggered by guest-host interactions, for the adsorption of benzene, toluene and p-xylene (BTX). The desorption capacity of different materials at various temperatures is examined. Adsorption/desorption performances are evaluated using both the static method (volumetric analysis) and the dynamic method. The latter allows for the co-adsorption of the pollutant in the presence of water. Unlike traditional AC, ZIFs demonstrate unaffected adsorption performance in the presence of water. Both AC and ZIF-7 undergo significant desorption at low temperatures (55 and 93% of adsorbed toluene, respectively), potentially releasing high concentrations of VOCs when exposed to solar radiation, which eliminates the possibility of its application for indoor air treatment. Remarkably, ZIF-8 does not show significant BTX desorption for temperatures below 50 degrees C (14%), while maintaining excellent regeneration characteristics at higher temperatures. We propose that this specific property can be depicted by a local dynamic-motion mechanism. Toluene is strongly diffusion-controlled, requiring the overcoming of a high energy barrier to cross the narrow six-membered ring aperture, while the size of the aperture is reduced by a ratio of the linker induced by the toluene packing in the sodalite (SOD) cavity.

Summary Monoterpenes are the most prevalent compounds found in essential oils. They exhibit inhibitory actions against phytopathogenic postharvest fungi. Direct application limits their effectiveness due to their instability, high volatility, hydrophobicity and susceptibility to degradation. Encapsulation systems using metal–organic frameworks (MOFs) have been developed to maximise their use. In this study, four protocols were shown to encapsulate thymol and limonene in porous solids, such as ZIF‐8, UiO‐66‐(COOH) 2 and zeolite 13X. Vapourisation and diffusion at 60 °C for 16 h was found to be the most efficient encapsulation process. A larger amount of thymol than limonene was loaded in the porous solids. Thymol released from MOFs slowed down the growth of Colletotrichum musae by up to 6 days at 25 °C. There was a sustained release of thymol even beyond the period of maximum fungal growth. This proof‐of‐concept study revealed the potential utility of MOFs as carriers of thymol against postharvest fungi.

Crown rot is an economically important postharvest disease of 'Cavendish' banana fruit caused by a complex of phytopathogenic fungi including Colletotrichum musae. The sustained release of bioactive compounds, such as thymol, encapsulated in porous materials has been studied for applications in postharvest fruit treatments. The release concentrations of thymol in its vapor phase, its evolution, and its impact on fruit preservation, or damage, have rarely been reported. In this study, an 11-d in vivo assay at 14 degrees C clearly demonstrated the contrasting effects of thymol vapor on banana fruit internal crown rot and phytotoxicity. Thymol vapor achieved by sublimation reduced necrosis in the crown from 40 % to 4 %. However, it triggered phytotoxicity, which caused damage to the fruit peel. Metal-organic frameworks (MOFs), in this case ZIF-8, UiO-66-(COOH)2 and zeolite 13X enabled the sustained and controlled release of thymol. When encapsulated in ZIF-8, thymol had a release rate approximately 200 times slower than its sublimation rate at 30 degrees C. Despite the slower release kinetics, thymol released from ZIF-8 achieved concentrations that reduced internal crown rot, to the same extent as thymol sublimation. Moreover, the controlled release minimized phytotoxicity.

An air handling system is an essential component for removing water vapor from the humid air stream used to supply air in medical facilities. Columns with pressure swing adsorption (PSA) technology are used to dry the humid air stream. These columns contain multiple moisture adsorbents connected in series, usually alumina, activated carbon, and hopcalite. In this study, a dynamic multiscale model was developed to simulate the adsorption and desorption process in a fixed bed for air drying. This model is described by equations of mass balance, thermodynamics, hydrodynamics, and adsorption/desorption kinetics. The temperature-dependent Toth-Aranovich-Donohue equation was applied to approximate the equilibrium relationship of water vapor on activated alumina and hopcalite. Breakthrough curve measurements at various water vapor concentration and gas flow rate were used to identify the different kinetic resistances, particularly the axial dispersion, external film mass transfer, pore diffusion, and internal mass transport, allowing determination of the limiting resistance of the process. Model predictions and measurements showed good agreement, quantified by performance indices and confirmed by a Kolmogorov-Smirnov test using additional breakthrough curves different from those used to identify parameters. The validated model is suitable for predicting adsorption and desorption breakthrough curves of water vapor on moisture adsorbents as a function of concentration, flow rate, and temperature and can be used as a predictive tool for developing and optimizing commercial PSA columns with multiple layers of adsorbents.

The synthesis of dimethyl carbonate (DMC) from carbon dioxide and methanol was studied over a ceria- zirconia mixed metal oxide. When using oxygen-18 labeled ceria-zirconia, no oxygen-18 labeled DMC or water was observed. On the other hand, using oxygen-18 labeled methanol led almost exclusively to the formation of double labeled DMC, CH318O (C16O) 18OCH3. These results were used to further elaborate the proposed reaction mechanisms for DMC synthesis. The rate-controlling step identified was that of a nucleophilic attack of gas phase methanol on surface monomethyl carbonate species to form DMC.

A static volumetric method measured the equilibrium adsorption isotherms of water vapor on commercial activated carbon, alumina and hopcalite adsorbents. A type II isotherm represents water vapor adsorption on alumina and hopcalite, whereas a type V isotherm characterizes activated carbon. A method based on the sensitivity analysis of parameters is used to evaluate the estimability of unknown parameters involved in the Toth-Aranovich–Donohue (type II) and Mahle (type V) adsorption isotherm equations. The estimable parameters are then identified using experimental water vapor measurements at three different temperatures, i.e., 293, 303 and 313 K and pressures up to the saturated concentration, simultaneously. The isotherm modeling methodology is implemented and solved within COMSOL Multiphysics®. The results of the isotherm model using the fitted parameters show excellent agreement with the experimental measurements. Thus, this is confirmed by the performance indices such as the Pearson correlation coefficient and the mean square error. In addition, the isosteric water vapor heat of adsorption is estimated using the Clausius-Clapeyron equation and the temperature-dependent models developed for each adsorbent.

Dynamic reactor operations will gain interest with the increase of intermittent electricity from renewable sources. Periodic operation of catalytic reactors can also be used for kinetic studies with better parameter estimation than steady‐state operation. This methodology is exemplified for the case of acetylene hydrogenation over Pd/α‐Al 2 O 3 using small amplitude flow oscillations. It allows the evaluation of several elementary kinetic parameters from one set of dynamic data for a reaction mechanism based on a single catalytic site. The optimized transient model is able to reproduce the time‐evolution of the reactant and product molar fractions at the outlet of a fixed bed operated with modulations of different amplitudes and frequencies. It further shows that the acetylene conversion is controlled by two steps, the hydrogen adsorption step and the hydrogenation of the surface vinyl intermediate into adsorbed ethylene.

Cyclohexane is a representative of volatile organic compounds (VOCs). VOCs can cause serious health problems in case of continuous exposure; therefore, it is essential to develop efficient personal protective equipment. Historically, activated carbons are used as VOC adsorbents. However, the emergence of promising novel adsorbents, such as metal-organic frameworks, has pushed the research to study their behavior under the same conditions. In this work, the use of the well-known HKUST-1 MOF of different particle sizes (20 μm, 300-600 μm, and 1-1.18 mm) for the adsorption of low-grade (5000 ppm) cyclohexane combined with different water concentrations (dry, 27 and 80% RH) in a fixed bed is proposed. The results were compared under the same conditions for a typically used activated carbon, PICACTIF TA 60. HKUST-1 has higher affinity to cyclohexane than PICACTIF for the whole pressure range studied, especially at low partial pressures. It begins to adsorb much earlier (0.0025 kPa) than the activated carbon (0.01 kPa). However, a different adsorption behavior is evidenced for both materials in the presence of water vapor since HKUST-1 is very hydrophilic in the zone near to the copper open metal sites, whereas PICACTIF is hydrophobic. After three consecutive cycles, good stability results were obtained for the MOF, comparable to activated carbon, even in the presence of water. As the main finding, although the unstability of HKUST-1 is well established under high humid conditions, the kinetic of degradation has not been established so far. Here, it is shown that the time usage of HKUST-1 as the adsorbent for respiratory mask (single pass) is not affected by the degradation of the structure, which may occur on a longer time scale. Finally, shaping by tableting provides good results since it is possible to increase the MOF density by around 69% with minor loss of adsorption capacity. The best fraction is 300-600 μm, reaching cyclohexane breakthrough times around 85 min/cm3 at 80% RH, comparable with PICACTIF-activated carbon and promising for practical applications.

The multiscale porosity of hierarchical zeolite materials is analyzed through advanced adsorption-based characterization in conjunction with additional techniques including electron tomography.