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[Display omitted] Aqueous zinc batteries (AZBs) with the advantages of safety, low cost, and sustainability are promising candidates for large-scale energy storage devices. However, the issues of interface side reactions and dendrite growth at the zinc metal anode (ZMA) significantly harm the cycling lifespan of AZBs. In this study, we designed a nano-molecular sieve additive, fullerenol (C 60 (OH) n), which possesses a surface rich in hydroxyl groups that can be uniformly dispersed in the aqueous solution, and captures free water in the electrolyte, thereby suppressing the occurrence of interfacial corrosion. Besides, fullerenol can be further reduced to fullerene (C 60) on the surface of ZMA, holding a unique self-smoothing effect that can inhibit the growth of dendritic Zn. With the synergistic action of these two effects, the fullerenol-contained electrolyte (FE) enables dendrite-free ZMAs. The Zn−Ti half-cell using FE exhibits stable cycling over 2500 times at 5 mA cm−2 with an average Coulombic efficiency as high as 99.8 %. Additionally, the Zn−NaV 3 O 8 cell using this electrolyte displays a capacity retention rate of 100 % after 1000 cycles at −20 °C. This work provides important insights into the molecular design of multifunctional electrolyte additives. [ABSTRACT FROM AUTHOR]

Efficient separation of liner alkanes from branched alkanes is of prime importance in the petrochemical industry. Herein an adaptive metal‐organic framework FJI‐H38 is reported with 1D channel which can vary delicately ≈4.0 Å. The activated FJI‐H38 displays extremely large butane (n‐C4H10) capacity, especially at low pressure (44.15 cm3 g−1 at 298 K and 0.1 bar), but barely adsorbs isobutane (iso‐C4H10). Remarkably, FJI‐H38 possesses a high n‐C4H10/iso‐C4H10 selectivity of 246.75. Gas‐loaded single crystal X‐ray analysis and modeling calculation reveal that the synergetic effect of pore confinement and surfaces decorated with uncoordinated carboxyl group plays a critical role in the capture of the relatively smaller n‐C4H10 while the exclusion of the larger iso‐C4H10. In addition, dynamic breakthrough tests explicitly prove FJI‐H38 displays prominent separation performance for n/iso‐C4H10 under various conditions with ultra‐high productivity of high‐purity n‐C4H10 (42.48 L/kg, ≥99.0%) and iso‐C4H10 (42.35 L/kg, ≥99.95%). [ABSTRACT FROM AUTHOR]

Abstract We herein disclosed an efficient multiphase Fenton-like catalytic system for oxidative degradation of chitosan. By utilizing Fe-MCM-41, featured with regular mesoporous structure and high specific surface area, the activation efficiency of H2O2 was significantly enhanced and the chitosan degradation efficiency proved by 28.1% higher than the conventional system using H2O2 alone. Under optimized conditions (5 g/L chitosan, 0.5 g/L Fe-MCM-41, 0.16 mol/L CH3COOH, 0.86 mol/L H2O2, 50 °C, 140 min), the viscosity reduction rate of chitosan reached an impressive 98.2%. Among the catalysts tested, Fe-MCM-41 with a loading factor of x = 0.12 demonstrated optimal degradation performance. After four recycles, the degradation efficiency maintained > 93.6%, demonstrating its excellent stability and recyclability for potential industrial applications. Kinetic studies provided further elucidation of the reaction mechanism, which indicated that the degradation process of chitosan followed a first-order kinetic model, with an apparent activation energy (Ea) of 48.91 kJ/mol. This novel and efficient strategy for chitosan degradation, addressed the challenges of catalyst recovery and secondary pollution typically associated with traditional Fenton systems, and posed broad application potential for polysaccharide material processing.

Inert gas argon has important applications in the fields of daily life, industrial manufacture and nuclear environmental monitoring. The key to its application is to selectively and efficiently separate and purify Ar from complex gas components. However, the separation of O2 and Ar at normal temperature is full of challenge due to their similar molecular sizes and adsorption properties as well as their close boiling point. In industry, high purity Ar is mainly produced by low temperature rectification, which is mature technology, but the equipment is large, high-energy consumption and explosive. Adsorption separation is a common method of gas separation. Molecular sieves are the most widely used material due to their huge specific surface area, aboudant pore structure and excellent adsorption properties. The silica tetrahedron in molecular sieve is electrically neutral, while the aluminum tetrahedron is electronegative, which makes it necessary to use H+ or Na+ outside the molecular sieve skeleton to maintain electrical neutrality. In actual application, the interaction between adsorbent and adsorbent can be enhanced by ion-exchange modification of molecular sieve material, so as to effectively improve the O2/Ar separation capacity of molecular sieve. In this paper, the application of ion-exchange modified molecular sieve materials in the field of O2/Ar adsorption separation was systematically summarized and reviewed. The results show that the O2/Ar separation coefficients of molecular sieves modified by alkaline earth metal ions like Ca2+, Sr2+ and Ba2+ can reach about 2.0, while that of Ce3+-exchanged X-type molecular sieve is as high as 5.9, it is an ideal adsorption material for O2/Ar separation. However, the high separation coefficient is limited to the range of low partial pressure, and the O2/Ar separation coefficient under normal pressure is below 2.0. The Ag+-exchanged molecular sieves, namely silver-loaded molecular sieves, have excellent Ar adsorption selectivity. At present, the O2/Ar separation coefficients of silver-loaded molecular sieve materials at atmospheric pressure are around 2.0, but the preparation cost of silver-loaded molecular sieves is high, and it is more suitable for small-scale separation applications, it means that the efficient separation of O2 and Ar at normal temperature and pressure is still challenging. The development of novel ion-exchange modified molecular sieve materials with high adsorption capacity and high adsorption selectivity for the separation of O2 and Ar is still one of the focuses and trends of future research projects.

[Display omitted] Uneven lithium deposition poses a primary challenge for lithium-ion batteries, as it often triggers the growth of lithium dendrites, thereby significantly compromising battery performance and potentially giving rise to safety concerns. Therefore, the high level of safety must be guaranteed to achieve the large-scale application of battery energy storage systems. Here, we present a novel separator design achieved by incorporating a two-dimensional A-type molecular sieve coating onto the polypropylene separator surface, which functions as an effective lithium ion redistribution layer. The results demonstrated that even after undergoing 1000 cycles, the cell equipped with a two-dimensional A-type molecular sieve-Polypropylene (2D-A-PP) separator still maintains an impressive capacity retention rate of 70 %. In contrast, cells equipped with Polypropylene (PP) separators exhibit capacity retention rates below 50 % after only 500 cycles. Additionally, the incorporation of a two-dimensional molecular sieve enhances the mechanical properties of the PP separator, thereby bolstering battery safety. This study proposes a novel concept for the design of lithium-ion battery separator materials, offering a fresh perspective on the development of separators with exceptional thermal stability, enhanced porosity, superior electrolyte affinity, and effective inhibition of lithium dendrite formation. [ABSTRACT FROM AUTHOR]

Hydrofluoric acid (HF)‐induced electrode and interfacial structure degeneration poses a significant challenge for high‐voltage lithium metal batteries (LMBs). To address this issue, we propose a separator strategy that involves decorating a regular polyethylene (PE) separator with molecular sieves (TW) impregnated with piperidine (PI). The porous structure of the TW serves as a reaction chamber for PI and HF. As a result, the HF content in the controlled electrolyte with 500 ppm H2O (ELE‐500) is notably reduced when using TW@PI‐PE separators, thereby shielding nickel‐rich cathodes from HF etching. Simultaneously, due to the hydrolysis of Li salts, and the inertness of PI towards H2O, a uniform lithium fluoride (LiF)‐rich solid electrolyte interphase can form on the Li metal anode, further mitigating dendrite formation. The lifespan of the symmetric Li cell using the TW@PI‐PE separator is doubled in ELE‐500, exhibiting stable 500‐hour cycles at 3 mA cm−2 and 3 mAh cm−2. Additionally, with the effective limitation of transition metal (TM) dissolution, the 4.6‐V LMBs employing a LiNi0.8Co0.1Mn0.1O2 cathode maintain an 81 % capacity retention over 100 cycles, even in ELE‐1000. The innovative TW@PI system presented here offers a fresh perspective for future research aimed at eliminating HF in LMBs. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study focuses on the efficient removal of Ni(II) from spent lithium-ion batteries (LIBs) to support environmental conservation and sustainable resource management. A composite material, known as molecular sieve (MS)-based metal–organic framework (MOF) composites (MMCs), consisting of a synthesized MS matrix with integrated MOFs, was developed for the adsorption of Ni(II). The structural and performance characteristics of the MMCs were evaluated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and N2 adsorption–desorption isotherms (BET). Batch adsorption experiments were conducted to assess the Ni(II) adsorption performance of the MMCs. The results revealed that, under conditions of pH 8 and a temperature of 298 K, the MMCs achieved near-equilibrium Ni(II) adsorption within 6 h, with a maximum theoretical adsorption capacity of 204.1 mg/g. Further analysis of the adsorption data confirmed that the adsorption process followed a pseudo-second-order kinetic model and Langmuir isotherm model, indicating a spontaneous, endothermic chemical adsorption mechanism. Importantly, the MMCs exhibited superior Ni(II) adsorption compared to the MS. This study provides valuable insights into the effective recovery and recycling of Ni(II) from spent LIBs, emphasizing its significance for environmental sustainability and resource circularity. [ABSTRACT FROM AUTHOR]

Molecular sieves 4A zeolite are materials used to dehydrate natural gas in liquefaction plants (LNG) in Algeria. After several cycles of regeneration and reuse, their structures degrade and affect their performances. Once replaced by new ones, they will be stored within the plant as an industrial used 4Azeolite (U4AZ). The aim of this study is to investigate the possibility of using U4AZ as an adsorbent for removing phenol and ethanol from aqueous solutions in a fixed bed column. Breakthrough curves were plotted for the adsorption of ethanol and phenol on the adsorbent U4AZ by varying initial concentrations (281, 444 mg/L) and contact time for constant flow rate (0.5 mL/min). The experimental data were fitted by empirical relationship based on Bohart-Adams model. The obtained correlations were in good agreement with the experimental breakthrough curve data. This investigation indicated that U4AZ could be used as a recyclable material to remove phenol and ethanol from aqueous solution by adsorption. [ABSTRACT FROM AUTHOR]

The adsorption properties of zeolite-like materials—aluminophosphate molecular sieves AFI and AEL—with respect to a wide range of organic compounds were studied using reversed gas chromatography. The specific retention volumes were obtained, and the molar changes in the internal energy and entropy during adsorption were calculated. The samples are capable of structure-selective adsorption. A molecular sieve effect was found for arenes and n-alcohols. On the AFI sample, the specific retention volume for ortho-xylene is smaller than for toluene. On the AEL sample, the retention of arenes varies in the series: toluene < benzene < xylenes. An analysis of the thermodynamic characteristics of adsorption shows that the additivity of adsorption heats in the homologous series is violated. This indicates the presence of pores in the aluminophosphate molecular sieves. The obtained tendencies in the adsorption of organic compounds can be used for adsorption and catalytic processes involving the studied materials. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During D-T fusion operations the capture, purification, and recycling of unburned tritium will be crucial, as the formation of tritium containing molecules require additional processing. Removing the tritium can require costly processing to be unbound from the tritium-containing molecules and improvements to these processes will be necessary moving forward. Existing techniques using sorbent material beds to remove tritium-containing molecules from process gas streams undergo repeated high-heat cycling which leads to diminished bed lifespans, necessitating replacement and associated downtime. This work demonstrates the capture and isotopic exchange technique of deuterated ammonia (ND 3), used as a surrogate for tritium, at ambient temperature using a Pt catalyst-loaded 13X molecular sieve. Unmodified 13X molecular sieve is capable of adsorbing and retaining the ND 3 however, incorporation of a catalyst facilitates the isotopic exchange of the hydrogen isotopes. The effluent gas streams were analyzed in conjunction with desorbed ammonia isotopologues post-exchange to verify these results. Isotopically exchanging and removing heavier hydrogen isotopes using this technique provides an alternative to traditional removal methods. • Hydrogen isotopes successfully exchanged at ambient temperature with Pt catalyst present on support material. • Pt-loaded 13X demonstrates higher capacity for ND 3 when compared to 13X • Pt-loaded 13X requires lower temperatures for full desorption of ND 3 when compared to 13X [ABSTRACT FROM AUTHOR]

Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carbon coating layers have been found to improve the catalytic performance of transition metals, which is usually explained as an outcome of electronic synergistic effect. Herein we reveal that the defective graphitic carbon, with a unique interlayer gap of 0.342 nm, can be a highly selective natural molecular sieve. It allows efficient diffusion of hydrogen molecules or radicals both along the in‐plane and out‐of‐plane direction, but sterically hinders the diffusion of molecules with larger kinetic diameter (e.g., CO and O2) along the in‐plane direction. As a result, poisonous species lager than 0.342 nm are sieved out, even when their adsorption on the metal is thermodynamically strong; at the same time, the interaction between H2 and the metal is not affected. This natural molecular sieve provides a very chance for constructing robust metal catalysts for hydrogen‐relevant processes, which are more tolerant to chemical or electrochemical oxidation or CO‐relevant poisoning. [ABSTRACT FROM AUTHOR]

Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tunnel‐structured manganese dioxides (MnO2), also known as octahedral molecule sieves (OMS), are widely studied in geochemistry, deionization, energy storage and (electro)catalysis. These functionalities originate from their characteristic sub‐nanoscale tunnel framework, which, with a high degree of structural polymorphism and rich surface chemistry, can reversibly absorb and transport various ions. An intensive understanding of their structure–property relationship is prerequisite for functionality optimization, which has been recently approached by implementation of advanced (in situ) characterizations providing significant atomistic sciences. This review will thus timely cover recent advancements related to OMS and their energy storage applications, with a focus on the atomistic insights pioneered by researchers including our group: the origins of structural polymorphism and heterogeneity, the evolution of faceted OMS crystals and its effect on electrocatalysis, the ion transport/storage properties and their implication for processing OMS. These studies represent a clear rational behind recent endeavors investigating the historically applied OMS materials, the summary of which is expected to deepen the scientific understandings and guide material engineering for functionality control. [ABSTRACT FROM AUTHOR]

Improper disposal of waste plastic has caused serious ecological and environmental pollution problems. Transforming plastics into high value-added chemicals can not only achieve efficient recycling of waste plastics, but is also an effective way to control white pollution. The catalyst selectively breaks the C–C bond of polyolefin plastic under heat treatment and converts it into liquid fuel, thus realizing sustainable recycling of plastics and has a good development prospect. This review provides a detailed overview of the current development of catalytic pyrolysis, catalytic hydrolysis, solvent decomposition, and supercritical hydrothermal liquefaction for cracking plastics to make fuel oil. The reaction mechanism, influencing factors, and promoting effects of catalysts in various degradation technologies are analyzed and summarized, and the latest proposed tandem reaction for degrading plastics is briefly introduced. Finally, some optimization paths of waste plastic pyrolysis to fuel oil technology are proposed: synergies between mixed raw materials, in-depth exploration of catalysts, design and manufacture of reactors that match the pyrolysis technology. All these are important research directions for promoting the industrialization of plastic pyrolysis to fuel oil. [ABSTRACT FROM AUTHOR]

The emergence of MOF–based separation membranes has transformed liquid contaminant filtration with impressive sieving properties. However, their use in multiphase water filtration is hindered by a limited sieving range and susceptibility to collapse in solution. To address this challenge, an innovative solution is presented: the Multilevel Cellular Graphene Skeleton (MCGK) induced by femtosecond laser, onto which a continuous MOF nanolayer (CMN), specifically ZIF–8, is grown. This forms a groundbreaking multistage micron/nanocomposite pore membrane. The MCGK/CMN membrane significantly expands the range of filterable contaminants and enhances stability. It utilizes a multilevel, multi–pore size sieving strategy for effective multiphase water filtration, achieving an impressive 90% efficiency in self–driven solar steam generation sieving. Additionally, it excels in removing organic pollutants and over 80% of volatile organic compounds (VOCs), while reducing metal ion concentrations. In liquid pressure–driven filtration, it achieves complete oil adsorption and reduces VOCs and metal ion concentrations. This innovative multistage micron/nanocomposite pore membrane holds great potential for diverse practical applications and provides insights for next–generation nanofiltration membranes, promising more efficient and resilient water purification technologies in the future. [ABSTRACT FROM AUTHOR]

ObjectiveThe aim is to remove the SO2 impurities in the alkylated C4 as the raw material of the mixed dehydrogenation device and control the SO2 volume fraction less than 1×10-6. Methods The liquid-phase high-precision adsorption desulfurization process was used to achieve continuous operation by adsorption regeneration. When the raw material was saturated by removing SO2 with adsorption, the adsorption capacity of SO2 adsorbent could be restored by means of nitrogen cycle replacement, heating stripping and air regeneration in the process, and put into production again to ensure the safe, stable and long-term operation of the unit. ResultThe SO2 volume fraction in alkylated C4 could be removed from 30×10-6-400×10-6 to less than 1×10-6 by adopting the liquid-phase high-precision adsorption desulfurization process. ConclusionsThe adsorbent and process flow of the adsorption desulfurization process were optimized and adjusted, which shortened the regeneration time of the adsorbent and ensured the continuous operation of the device industrialization. At the same time, the liquid phase high-precision adsorption desulfurization process is simple to operate, which has low energy consumption and safety risk. [ABSTRACT FROM AUTHOR]

One of the widely used methods to remove acid gas is surface adsorption using solid molecular sieves. The advantages of H2S adsorption with molecular sieves can be seen in the reversibility of the process, chemical and thermal stability, no secondary product, and the high selectivity of H2S in these adsorbents. Therefore, in this study, Aspen-Adsim software was used to investigate the effect of various parameters on adsorption of H2S on 4A molecular sieve adsorbent. The desired bed is considered vertical and one-dimensional. The results related to the breakthrough curves and saturation time showed that the maximum amount of adsorption occurred in the early times. As the adsorption time increases, the rate of H2S adsorption decreases. The results of investigating the effect of operating parameters showed that increasing the tower pressure from 90 to 104 bar reduces the output H2S content by 21 ppm. Also, reducing the feed temperature showed significant results on the amount of H2S absorption and the reduction of the output H2S content, so that for every one degree of temperature reduction in the feed gas temperature, the dew point temperature of the output was reduced by 1.6°C. Due to the high amount of absorbent and its heat capacity compared to the amount of H2S in the gas phase, a slight temperature increase occurs along the tower so that the difference between the inlet and outlet temperatures does not exceed 1˚C. According to the breakthrough curve, it was also determined that after 7920 seconds, the entire bed of the tower is saturated with H2S molecules. [ABSTRACT FROM AUTHOR]

In recent years, the non-petroleum production of light olefins has been the research focus of Fischer–Tropsch olefin synthesis (FTO). Iron-based catalysts have attracted much attention because of their low price, high catalytic activity, and wide temperature range. In this paper, traditional modification, hydrophobic modification, and amphiphobic modification of the catalyst are summarized and analyzed. It was found that traditional modification (changing the pore size and surface pH of the catalyst) will reduce the dispersion of Fe, change the active center of the catalyst, and improve the selectivity of light olefins (for example, SiO2: 32%). However, compared with functional methods, these traditional methods lead to poor stability and high carbon dioxide selectivity (for example, SiO2: 34%). Hydrophobic modification can inhibit the adsorption and retention of water molecules on the catalyst and reduce the local water pressure near the iron species in the nuclear layer, thus inhibiting the further formation of CO2 (for example, SiO2: 5%) of the WGSR. Amphiphobic modification can not only inhibit the WGSR, but also reduce the steric hindrance of the catalyst, increase the diffusion rate of olefins, and inhibit the reabsorption of olefins. Follow-up research should focus on these issues. [ABSTRACT FROM AUTHOR]

The presence of moisture is one of the factors that promote degradation of transformer insulating oils and deterioration of cellulose insulation materials in oil-immersed power transformers, which affect the lifespan of the transformers. Realizing the importance of moisture in transformer insulating oils, this study compares the effectiveness of three moisture treatment techniques nitrogen bubbling technique (NBT), molecular sieve technique (MST), and vacuum oven technique (VOT)) for mineral oil (MO). The moisture content and AC breakdown voltage of the MO samples before and after moisture treatment were measured using Karl Fischer coulometric titrator and portable oil tester, respectively, in accordance with the American Society for Testing and Materials (ASTM) D1533 and ASTM D1816 standards. The results showed that NBT is the best moisture treatment technique for the MO, where the NBT reduced 80.79% of moisture present in the oil, followed by MST and VOT, which reduced 72.87 and 42.28% of moisture, respectively. The results also showed that the AC breakdown voltage of the MO samples after moisture treatment was improved owing to the reduction in moisture content. [ABSTRACT FROM AUTHOR]

【Objective】 To explore the effects of new composite hydrogel on the physiological characteristics of tobacco seedlings under drought stress, and to provide theoretical basis for alleviating the toxicity of drought stress to tobacco. 【Method】 A total of 10 treatments including CK control and three different hydrogels added at 0.1%, 0.5% and 0.9% of soil dry mass: commercial hydrogel HS, new composite hydrogel HM (polyvinyl alcohol-acrylic acid-molecular sieve hydrogel) and HB (polyvinyl alcohol-acrylic acid-biochar hydrogel) were designed by pot experiment to study the effects of new composite hydrogels on tobacco under drought stress The effects of the new composite hydrogels on biomass accumulation, root development, photosynthetic system and oxidative stress of tobacco under drought stress were investigated. 【Result】 Under the same dosage conditions, HM and HB treatments were effective in increasing the fresh mass, dry mass and total water content of tobacco under drought stress compared to HS treatment. Compared with CK, HM and HB treatments could increase the fresh mass by a maximum of 153.91% and 126.34%, respectively. Under the same dosage conditions, HM and HB treatments significantly increased the total root length, total root surface area, average root diameter, root tip number and root volume, and improved the root vigor of tobacco compared with HS treatments; photosynthetic parameters and SPAD values of tobacco increased significantly and improved leaf stomatal status; SOD (superoxide dismutase), POD (peroxidase) and CAT (catalase) activities and soluble protein amounts of tobacco increased and MDA (malondialdehyde) amounts decreased significantly, which enhanced the resistance of tobacco. 【Conclusion】 Adding 0.9% HM and HB hydrogels to soil dry weight can effectively reduce the impact of drought stress on tobacco and improve tobacco drought resistance.

This study focuses on the efficient removal of Ni(II) from spent lithium-ion batteries (LIBs) to support environmental conservation and sustainable resource management. A composite material, known as molecular sieve (MS)-based metal–organic framework (MOF) composites (MMCs), consisting of a synthesized MS matrix with integrated MOFs, was developed for the adsorption of Ni(II). The structural and performance characteristics of the MMCs were evaluated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and N2 adsorption–desorption isotherms (BET). Batch adsorption experiments were conducted to assess the Ni(II) adsorption performance of the MMCs. The results revealed that, under conditions of pH 8 and a temperature of 298 K, the MMCs achieved near-equilibrium Ni(II) adsorption within 6 h, with a maximum theoretical adsorption capacity of 204.1 mg/g. Further analysis of the adsorption data confirmed that the adsorption process followed a pseudo-second-order kinetic model and Langmuir isotherm model, indicating a spontaneous, endothermic chemical adsorption mechanism. Importantly, the MMCs exhibited superior Ni(II) adsorption compared to the MS. This study provides valuable insights into the effective recovery and recycling of Ni(II) from spent LIBs, emphasizing its significance for environmental sustainability and resource circularity.

In recent years, the chemical reactions with plasma catalysis have been attracted attention. The interaction between plasma ant catalyst can wide the process window, realizing the low pressure and low temperature processes with various catalysts. However, the wide process range make it difficult to optimization for social implement. The key lies in elucidating the reaction mechanism, predicting reactions through numerical simulations, and deriving optimal conditions. On the other hand, recent research has suggested that the use of molecular sieves (MS) can improve methanation efficiency. This can be combined with catalysts, offering new potential applications of MS in chemical reactions. Here, we investigated the more efficient combination of plasma and MS and their reaction mechanisms. As a result, it was found that: 1. The use of MS reduces the oxidation source in the gas phase, leading to an increase in methanation efficiency by suppressing reverse reactions. 2. The adsorption effect of MS, which suppress the reverse reaction, increases with higher pressure. 3. MS in plasma decrease the energy in plasma decrease the energy within the plasma, reducing the CO2 decomposition rate due to electron impact.

Molecular sieves, a type of material with porous structure, are able to separate small molecules. Classical molecular sieves have been investigated thoroughly, but they have limitations as well. For example, they are unable to separate chemicals with similar physical properties. In recent years, scientists have begun to focus on "nonclassical" methods for chemical separation. Many achievements have been made, such as microporous membranes, porous liquid and cage-like molecules. Some of these methods may greatly reduce the cost of industrial production and even have a great influence on social and economic development. In this review, the novel methods are discussed, and the development trend of this research field is provided. [ABSTRACT FROM AUTHOR]

An advanced strategy was developed for the synthesis of molecular sieve-supported Pd catalysts. In this method, reductant containing C=C was in-situ prepared and pre-dispersed in the pore of the zeolites. The C=C group in the reductant can reduce the Pd2+ to Pd0 efficiently, leading to the formation of small and uniform Pd nanoparticles (~2 nm). The physical and chemical properties of the catalyst were characterized by XRD, TEM, XPS (ICP-OES), N2 isothermal adsorption-desorption, and H2-TPR. These catalysts showed high catalytic performance for the hydrogenation of nitrobenzene to aniline. All the TOFs for 1.5 Pd/Y, 1.5 Pd/ZSM-5, and 1.5 Pd/MOR with 1.5 wt% Pd loading are higher than 1000 h−1 at 30 °C and 0.1 MPa H2. Meanwhile, kinetic analysis for 2.0 Pd/Y was carried out, and an apparent activation energy of 28.88 kJ mol−1 was obtained, which is lower than most of the reported values in the literature. Furthermore, these catalysts were stable and recyclable. [ABSTRACT FROM AUTHOR]

NOx is a common atmospheric pollutant, and NH3‐SCR technology efficiently purifies it. CeCuOx binary‐oxide nanoparticles were synthesized and loaded onto acid MCM‐49 molecular sieve with a large specific surface area to increase acid sites and disperse active sites of the catalyst. The optimized 35 % CeCu/MCM‐49 catalyst effectively purified over 80 % of NOx in the temperature range of 200–500 °C and demonstrated excellent resistance to alkali metals, such as K, Na, and Ca. Even after K poisoning, it still removed over 80 % of NOx in the range of 200–450 °C. Various characterization methods, including XRD, FT‐IR, TEM, and N2 isotherm adsorption‐desorption tests, confirmed the structure of the catalyst remained intact after poisoning with no substance change, nor agglomeration of nanoparticles. NH3‐TPD and H2‐TPR confirmed that the catalyst had effective acidity and redox capacity that were not affected by alkali metals. In‐situ DRIFTs showed that the catalytic reaction predominant mechanism shifted from L−H to E−R mechanism after poisoning. This study provides valuable insights into the development of high‐performance Ce‐based NH3‐SCR catalysts with alkali metal resistance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of East China University of Science & Technology is the property of Journal of East China University of Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a new type of photocatalyst, molecular sieve photocatalysts have shown a promising future in the degradation of organic matter in water bodies. In this paper, a new type of molecular sieve photocatalyst was successfully prepared by introducing Bi and La elements into the hydrothermal synthesis of SAPO-34 molecular sieve for the purpose of regulating the molecular sieve backbone. The introduction of active metals into the skeleton of molecular sieve can enrich the Lewis acids acid sites on its surface. At the same time, the introduction of active metals can accelerate the transition rate of photogenerated carriers, which can also suppress the compound rate of electron holes. Under the action of 500w mercury lamp, the degradation rate of 20 ml 0.5 mg/mL formaldehyde solution was 77.61% in 6 h. Meanwhile, the degradation rate constant k could reach 0.3222 min−1, indicating that the photocatalytic degradation of formaldehyde showed excellent performance. This study provides a new method for the preparation of molecular sieve photocatalysts and a new idea for the construction of bifunctional photocatalysts. [ABSTRACT FROM AUTHOR]

Carbon hydrocarbon compounds, especially low-carbon hydrocarbons (C1–C3), are vital raw materials in the petrochemical industry, but their efficient separation has great challenges due to their similar molecular structures and properties. In contrast to traditional low-temperature distillation and absorption separation technologies, selective adsorption employing porous materials as adsorbent has the advantages of low energy consumption, high efficiency, and high selectivity, indicating broad application possibilities in the field of low-carbon hydrocarbon separation. In this paper, the recent progress in the separation and purification of hydrocarbon mixtures by means of the two kinds of porous materials (metal–organic frameworks and molecular sieves) that have been widely used in recent years is reviewed, including purification of methane and separation of ethylene/ethane, propylene/propane, and some high-carbon hydrocarbon isomers. The structure–activity relationships between their chemical composition, structural characteristics, and separation performance are discussed to understand the separation mechanism. In conclusion, the issues encountered in the application of metal–organic frameworks and molecular sieves in the separation of low-carbon hydrocarbons are discussed in light of the current context of "carbon neutrality". [ABSTRACT FROM AUTHOR]

The input feed of natural gas dehydration units often contains significant quantities of mercaptan. To effectively separate water from the sweet gas stream, it is crucial to select an appropriate molecular sieve. Mercaptan adsorption can cause issues in later stages of the process. In this research, the Grand Canonical Monte Carlo (GCMC) method was employed to investigate the adsorption behavior of methane, ethane, water, methyl mercaptan, and carbonyl sulfide as both single and multicomponent gas mixtures on LTA zeolite with varying K/Na ratios. The obtained data were modeled using the Langmuir and Sips models, with the Sips model exhibiting better agreement with the simulation results. Gas adsorption simulations were conducted across temperatures of 323 K, 313 K, 303 K, and 333 K, a pressure range of 1–70 bar. The findings indicate that increasing temperature diminishes adsorption on LTA zeolite, while increasing pressure has an incremental effect on adsorption. Adsorption studies were performed for both wet and dry gas mixtures. A rise in the number of potassium ions within the zeolite structure resulted in decreased component adsorption, potentially due to the reduction in zeolite cavity size. The results emphasize that the sodium-to-potassium ratio plays a crucial role in mercaptan adsorption or depletion within the packed bed tower. For a gas mixture, it is not recommended to utilize LTA zeolite with a potassium content lower than 55% for gas adsorption due to its propensity to adsorb mercaptan. [Display omitted] • Pure and gas mixture adsorption was studied on LTA molecular sieve. • Effect of K/Na ion ratio on gas adsorption was investigated. • K/Na ratio has significant effect on mercaptan adsorption. • mercaptan is adsorbed after water mass transfer zone. • multicomponent adsorption was studied for wet and dry gas mixtures. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) have recently received considerable attention for the analysis and monitoring of different biochemical processes in biological systems such as humans, plants, and microorganisms. The advantage of using VOCs to gather information about a specific process is that they can be extracted using different types of samples, even at low concentrations. Therefore, VOC levels represent the fingerprints of specific biochemical processes. The aim of this work was to develop a sensor based on a photoionization detector (PID) and a zeolite layer, used as an alternative analytic separation technique for the analysis of VOCs. The identification of VOCs occurred through the evaluation of the emissive profile during the thermal desorption phase, using a stainless-steel chamber for analysis. Emission profiles were evaluated using a double exponential mathematical model, which fit well if compared with the physical system, describing both the evaporation and diffusion processes. The results showed that the zeolite layer was selective for propionic acid molecules if compared to succinic acid molecules, showing linear behavior even at low concentrations. The process to define the optimal adsorption time between the propionic acid molecules was performed in the range of 5 to 60 min, followed by a thermal desorption process at 100 °C. An investigation of the relationship between the evaporation and diffusion rates showed that the maximum concentration of detected propionic acid molecules occurred in 15 min. Other analyses were performed to study how the concentration of VOCs depended on the desorption temperature and the volume of the analysis chamber. For this purpose, tests were performed using three analysis chambers with volumes of 25 × 10−6, 50 × 10−6, and 150 × 10−6 m3 at three different desorption temperatures of 20 °C, 50 °C, and 100 °C, respectively. The results demonstrated that the evaporation rate of the VOCs increased rapidly with an increasing temperature, while the diffusion rate remained almost constant and was characterized by a slow decay time. The diffusion ratio increased when using a chamber with a larger volume. These results highlight the capabilities of this alternative technique for VOC analysis, even for samples with low concentrations. The coupling of a zeolite layer and a PID improves the detection selectivity in portable devices, demonstrating the feasibility of extending its use to a wide range of new applications. [ABSTRACT FROM AUTHOR]

We developed a passive sampler for time-integrated collection and radiocarbon (14C) analysis of soil respiration, a major flux in the global C cycle. It consists of a permanent access well that controls the CO2 uptake rate and an exchangeable molecular sieve CO2 trap. We tested how access well dimensions and environmental conditions affect collected CO2, and optimized cleaning procedures to minimize 14CO2 memory. We also deployed two generations of the sampler in Arctic tundra for up to two years, collecting CO2 over periods of 3 days-2 months, while monitoring soil temperature, volumetric water content, and CO2 concentration. The sampler collects CO2 at a rate proportional to the length of a silicone tubing inlet (7-26 g CO2-C day-1·m Si-1). With constant sampler dimensions in the field, CO2 recovery is best explained by soil temperature. We retrieved 0.1-5.3 mg C from the 1st and 0.6-13 mg C from the 2nd generation samplers, equivalent to uptake rates of 2-215 (n=17) and 10-247 g CO2-C day-1 (n=20), respectively. The method blank is 8 ± 6 g C (mean ± sd, n=8), with a radiocarbon content (fraction modern) ranging from 0.5875-0.6013 (n=2). The sampler enables more continuous investigations of soil C emission sources and is suitable for Arctic environments.

Radiocarbon (14C) measurements offer a unique investigative tool to study methane emissions by identifying fossil-fuel methane in air. Fossil-fuel methane is devoid of 14C and, when emitted to the atmosphere, causes a strong decrease in the ratio of radiocarbon to total carbon in methane (Δ14CH4). By observing the changes in Δ14CH4, the fossil fraction of methane emissions can be quantified. Presently, there are very few published Δ14CH4 measurements, mainly because it is challenging to collect and process the large volumes of air needed for radiocarbon measurements. We present a new sampling system that collects enough methane carbon for high precision Δ14CH4 measurements without having to transport large volumes of air. The system catalytically combusts CH4 into CO2 and adsorbs the combustion-derived CO2 onto a molecular sieve trap, after first removing CO2, CO, and H2O. Tests using reference air show a Δ14CH4 measurement repeatability of 5.4‰, similar or better than the precision in the most recent reported measurements. We use the system to produce the first Δ14CH4 measurements in central London and show that day-to-day differences in Δ14CH4 in these samples can be attributed to fossil methane input. The new system could be deployed in a range of settings to investigate CH4 sources.

Improper disposal of waste plastic has caused serious ecological and environmental pollution problems. Transforming plastics into high value-added chemicals can not only achieve efficient recycling of waste plastics, but is also an effective way to control white pollution. The catalyst selectively breaks the C–C bond of polyolefin plastic under heat treatment and converts it into liquid fuel, thus realizing sustainable recycling of plastics and has a good development prospect. This review provides a detailed overview of the current development of catalytic pyrolysis, catalytic hydrolysis, solvent decomposition, and supercritical hydrothermal liquefaction for cracking plastics to make fuel oil. The reaction mechanism, influencing factors, and promoting effects of catalysts in various degradation technologies are analyzed and summarized, and the latest proposed tandem reaction for degrading plastics is briefly introduced. Finally, some optimization paths of waste plastic pyrolysis to fuel oil technology are proposed: synergies between mixed raw materials, in-depth exploration of catalysts, design and manufacture of reactors that match the pyrolysis technology. All these are important research directions for promoting the industrialization of plastic pyrolysis to fuel oil.

In the process of oil exploitation, the addition of chlorine containing oilfield additives led to the chloride content in petroleum products seriously exceeding the standard, which led to a large number of organic chlorides entering the reforming feedstock oil, aggravated the corrosion of equipment and pipelines, caused catalyst poisoning and pipeline blockage, and endangered the normal operation of reforming equipment. At present, the main technologies of reforming oil dechlorination include catalytic hydrogenation dechlorination, extraction dechlorination, nucleophilic substitution dechlorination, adsorption dechlorination, etc. The research progress and existing problems of each technology are discussed, and on this basis, the adsorption dechlorination technology is emphatically introduced. Dechlorination agent is the core technology of adsorption dechlorination process. This article provides a detailed introduction to the research progress of metal oxide, activated carbon, and molecular sieve based adsorption and dechlorination agents, especially the analysis, discussion, and outlook on the modification process of molecular sieve based adsorbents. [ABSTRACT FROM AUTHOR]

Separating n‐butene and i‐butene by adsorption is an energy‐efficient alternative, but designing porous adsorbents that distinguish the subtle differences between the isomers is extremely challenging. Currently, adsorbents that can sieve 1‐butene isomers and are stable enough to withstand humid gas mixtures are largely unmet. Herein, we propose a robust ultramicroporous metal–organic framework (MET‐Fe) that can separate 1‐butene isomers through molecular exclusion. The pore aperture size (4.6 Å) precisely matches the kinetic diameters of the isomers, as verified by static and kinetic adsorption experiments and theoretical calculations. Furthermore, dynamic breakthrough experiments confirmed the excellent separation performance, easy regeneration, and remarkable reusability of MET‐Fe in both dry and humid conditions. With its high selectivity, large breakthrough capacity, and outstanding stability, MET‐Fe provides an ideal platform for industrial butene isomers separation. [ABSTRACT FROM AUTHOR]

In this paper, high value-added molecular sieves were prepared by extracting valuable components from low-temperature burned potassium feldspar with KOH as additive to make full use of potassium feldspar. At first, the best roasting conditions for extracting SiO2 from potassium feldspar by KOH medium temperature roasting are determined by single factor experiment: roasting temperature is 500℃, roasting time is 2.5 h, alkali-ore ratio is 2.5:1, and the dissolution rate of SiO2 can reach 99%. Through orthogonal experiment, the relationship of the three factors affecting the dissolution rate of SiO2 are: alkali-ore ratio, roasting temperature and time. Through kinetic analysis, the reaction process is a mixed control of chemical control and diffusion control, and the kinetic equation is [1 − (1 − α)1/3] = 5.1872exp[− 8832.72/(RT)]t. Finally, the W-type molecular sieve with pore volume of 0.013181 cc/g, specific surface area of 2.476 m2/g and moisture absorption rate of 6.06% is synthesized by hydrothermal method. [ABSTRACT FROM AUTHOR]

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The SBA-15 molecular sieve carrier with large specific surface area and pore volume, high temperature resistance and acid and alkali resistance was successfully synthesized by the method of hydrothermal synthesis. Then, ionic liquid is loaded on the surface and pores of the carrier by the impregnation method, so that it can be combined with the acid-base COS, thereby enhancing the adsorption effect and adsorption selectivity. Effects of three ionic liquids: 1-ethyl-3-methylimidazolium glycinate, 1-butyl-3-methylimidazolium glycinate and 1–(2-Aminoethyl)3-methylimidazolium bromide on the COS adsorption properties were discussed at different adsorption temperatures and loading concentrations. Among these mesoporous molecular sieves immobilized ionic liquids, the result from COS adsorption shows that the specific surface area of SBA-15 molecular sieve impregnated with 0.9 g·mL−1 [C 2 mim][Gly] (SBA-15-C 2 9.0) decreased from 902 m2·g−1 to SBA-15–27 m2·g−1. And its COS breakthrough adsorption capacity can reach 11.38 mg·g−1. It can concluded that [C 2 mim][Gly] is helpful to increase the adsorption capacity. [Display omitted] • Molecular sieves loaded with amine functional ionic liquids were first used for carbonyl sulfide adsorption. • The effect of ionic liquid on molecular sieve morphology and carrier pore size was investigated, respectively. • The adsorption performance of mesoporous SBA-15 molecular sieves loading [C 2 mim][Gly] on were discussed. [ABSTRACT FROM AUTHOR]

The paper describes the structure and iodine adsorption performance of Ag+ ion-exchange 13X molecular sieve (Ag-13X) with a small Si/Al ratio. The Ag-13X has a high specific surface area (408 m2/g) and a large amount of micropore volume (0.18 cm3/g). The Ag-13X presents a strong affinity with I2 and CH3I. The I2 static adsorption capacity of the 26.7% Ag zeolite reached 700 mg/g. The adsorption capacities under 1‰ and 1% CH3I feeds are up to 104.4 mg/g and 131 mg/g, respectively. This study indicates the applicability of Ag-13X in severe nuclear accidents. [ABSTRACT FROM AUTHOR]

Lynde Type-A (LTA) zeolite as being molecular sieve and hydrophilic zeolite is used to dehydrate water in the purification of bioethanol. LTA zeolite from LNZ has a small surface area of 29,62 m2/g. Adding HCl activators to LTA Zeolite from LNZ was carried out to increase the surface area of LTA zeolite. The activation of LTA zeolite was carried through in a closed erlemeyer with various HCl concentration: 10% w/w, 15 % w/w, and 20% w/w and the ratio acid/LTA zeolite was 10 ml: 1 gram. The XRD analysis showed that the structure of LTA zeolite activated does not change despite the process of activation, and the highest percentage of crystallinity was obtained at 68.25% wt by concentration of HCl at 20 % w/w. The result of XRF analysis showed that the highest of impurity removal and the highest of decreasing ratio of Si/Al was in the LTA zeolite activated by HCl 20% w/w. The result of BET analysis showed the largest surface area at 45.67 m2/g obtained by adding 10% w/w of HCl activator, which was 45.67 m2/g, and the size of zeolite’s pore volume was 0.027 cc/g. The result performance of LTA zeolite activated obtained the highest purity of bioethanol by 99.74 % v/v at HCl concentration 20% w/w.

Due to their ability to adsorb or absorb chemical pollutants, including organic compounds, sorbents are increasingly used in the reclamation of soils subjected to their pressure, which results from their high potential in eliminating xenobiotics. The precise optimization of the reclamation process is required, focused primarily on restoring the condition of the soil. This research are essential for seeking materials sufficiently potent to accelerate the remediation process and for expanding knowledge related to biochemical transformations that lead to the neutralization of these pollutants. The goal of this study was to determine and compare the sensitivity of soil enzymes to petroleum-derived products in soil sown with Zea mays, remediated using four sorbents. The study was conducted in a pot experiment, with loamy sand (LS) and sandy loam (SL) polluted with VERVA diesel oil (DO) and VERVA 98 petrol (P). Soil samples were collected from arable lands, and the effects of the tested pollutants were compared with those used as control uncontaminated soil samples in terms of Zea mays biomass and the activity of seven enzymes in the soil. The following sorbents were applied to mitigate DO and P effects on the test plants and enzymatic activity: molecular sieve (M), expanded clay (E), sepiolite (S), and Ikasorb (I). Both DO and P exerted a toxic effect on Zea mays, with DO more strongly disturbing its growth and development and the activities of soil enzymes than P. In sandy clay (SL), P was found to be a significant inhibitor of dehydrogenases (Deh), catalase (Cat), urease (Ure), alkaline phosphatase (Pal), and arylsulfatase (Aryl) activities, while DO stimulated the activity of all enzymes in this soil. The study results suggest that the sorbents tested, mainlya molecular sieve, may be useful in remediating DO-polluted soils, especially when alleviating the effects of these pollutants in soils of lower agronomic value. [ABSTRACT FROM AUTHOR]