Zeolite 4A Research Articles

Separation of ethylene and ethane using Co-Gallate pellets in a vacuum swing adsorption process

This work reports a vacuum swing adsorption (VSA) process that utilizes Co-gallate pellets to produce high-purity ethylene. The process is tested on two feed streams generated from the pyrolysis of naphtha and steam cracking of ethane, respectively. The VSA cycle consists of four steps: pressurization, adsorption, replacement with ethylene product and blowdown. A cyclic steady state (CSS) is reached for every test condition, verified by checking the profiles of column pressure, gas composition, and solid loading, which remain constant for ten subsequent cycles. Through analysis of the independent decision variables that affect the performance of the 80/20 (v/v) ethylene/ethane mixture separation, we identify desorption pressure and the replacement flowrate to feed flowrate ratio as the most significant factors. By optimizing these variables, we achieve an exceptional purity of 99.90% for ethylene with a 46.45% recovery and a productivity of 1.05 mol kg−1 per cycle. The Co-gallate adsorbent has a high affinity for ethylene and a low diffusion limitation, thus demonstrating superior potential for industrial ethylene/ethane separation compared to zeolite 4A and Ag+-Amberlyst 35.

Performance optimization of polyetherimide‐zeolite 4A mixed matrix membranes for carbon dioxide/methane separation process using response surface methodology

AbstractThe performance optimization studies of zeolite 4A embedded polyetherimide mixed matrix membranes to separate carbon dioxide/methane by simultaneously considering the effect of process parameters on process responses were the focus of this study. Mixed matrix membranes were characterized and analyzed. The thermophysical characteristics of the synthesized membranes were assessed by different analytical equipment. The permeability of pure gases was determined at varying feed pressures (4 bar to 10 bar) to evaluate gas separation performance. Process optimization studies were accomplished by response surface methodology to find the relation of pressure and zeolite loading on carbon dioxide and methane permeability, and carbon dioxide/methane selectivity. The characterization results revealed that all membranes were dense in structure and has improved thermal stability. The spectrometry results confirmed the molecular interaction between polyetherimide and zeolite 4A filler. Gas permeability results showed a more than 90 % increase in carbon dioxide permeability compared to the nascent polyetherimide membrane. Similarly, selectivity of mixed matrix membranes was 45 % higher than polyetherimide membrane. The optimal operating conditions were found to be 20 wt. % zeolite loading and 6 bar pressure with overall desirability of 0.700. These membranes can find potential in various gas separation applications.

Hydrogen capture using zeolite 3A for pipeline gas deblending

Less than 20% of hydrogen gas can be co-transported with natural gas (NG) and distributed to end-users using existing gas pipelines. However, most industrial gas turbines can only tolerate up to 1% by volume of hydrogen in natural gas. A separation process is needed to selectively capture the minor component such as hydrogen. Herein, we report the design of a deblending process to meet the requirements of these specific industries. We demonstrated that zeolite 3A which is believed to be a trapdoor zeolite has a selectivity towards hydrogen molecules based on the laboratory experiment results. A multiple-bed pressure swing adsorption (PSA) using zeolite 3A was subsequently modelled for removing hydrogen at various concentrations from the blended gas. The results indicate that high pressure and high purity methane (>99%) can be obtained by the 3A PSA, making products suitable for gas turbines. When a methane PSA with activated carbon (AC) adsorbents is used for comparison, the process needs to do separation work towards the major component methane and an overwhelming pump work is required to repressurize the desorbed methane gas. Therefore, a hydrogen capture PSA process with zeolite 3A stands out in terms of product purity, recovery and energy consumption, for low concentration H2 deblending from NG.

Highly efficient and selective Hg(II) adsorbent: ZnS grown on the surface of 4A zeolite and supported on starch aerogels

In this study, ZnS nanoparticles were loaded on the surface of zeolite NaA and embedded in a carbon aerogel to prepare C@zeolite-ZnS, where zeolite NaA was used in order to adsorb Zn2+ ions released during ion exchange, and the carbon aerogel had good dispersion as a carrier for ZnS to solve the ZnS agglomeration problem. The morphology and structure of C@zeolite-ZnS were characterized by FT-IR, XRD, SEM, BET, and XPS. C@zeolite-ZnS showed excellent selectivity and high removal rate for Hg(II) ions with a maximum adsorption capacity of 795.83 mg/g. When the pH, adsorption time, and Hg(II) ion concentration were 6, 30 min, and 25 mg/L at 298 K, the corresponding adsorption and removal rates reached 99.90% and 124.88 mg/g, respectively. Thermodynamic studies have shown that the adsorption process is a spontaneous heat absorption process. Furthermore, after up to 10 cycles of adsorption, the adsorbent still exhibited outstanding stability and high adsorption capacity with removal rates exceeding 99%. In conclusion, C@zeolite-ZnS, which is stable and reusable and has the ability to meet industrial emission standards after adsorption of Hg(II) ions, is very promising for industrial applications.

Development of High Temperature Water Sorbents Based on Zeolites, Dolomite, Lanthanum Oxide and Coke

Methanation is gaining attention as it produces green methane from CO2 and H2, through Power-to-Gas technology. This process could be improved by in situ water sorption. The main difficulty for this process intensification is to find effective water sorbents at useful reaction temperatures (275-400 °C). The present work comprises the study of the water sorption capacity of different materials at 25-400 °C. The sorption capacity of the most studied solid sorbents (zeolites 3A & 4A) was compared to other materials such as dolomite, La2O3 and cokes. In trying to improve their stability and sorption capacity at high temperatures, all these materials were modified with alkaline-earth metals (Ba, Ca & Mg). Lanthana-Ba and dolomite sorbents were the most promising materials, reaching water sorption values of 120 and 102 mgH2O/gsorbent, respectively, even at 300 °C, i.e., values 10-times higher than the achieved ones with zeolites 3A or 4A under the same operating conditions. At these high temperatures, around 300 °C, the water sorption process was concluded to be closer to chemisorption than to physisorption.

Zeolite 4A activates peroxymonosulfate toward the production of singlet oxygen for the selective degradation of organic pollutants

Zeolite 4A (Z4A), synthesized from natural kaolin by an easy and low-cost method, was used to activate inorganic peroxides for degrading organic pollutants in water. Z4A had a high catalytic capability for the activation of peroxymonosulfate (PMS) but a low effect on peroxydisulfate (PDS) or hydrogen peroxide (H2O2). The non-radical pathway dominated the degradation of the pollutants, due to acid-base interactions of PMS with Z4A, as indicated by the characterization of the fresh and used zeolite. Additionally, in the Z4A/PMS system, synergistic effects in the elimination of two representative contaminants (ciprofloxacin “CIP” and methyl orange “MO”) were observed. The Z4A/PMS system induced the opening of the piperazyl ring of CIP, and the cleavage of the azo-benzene bond of MO. These primary transformations occurred in electron-rich groups, as supported by theoretical analyses on atomic charge developed herein. Interestingly, Z4A showed high activating/degrading capability even after three reuse cycles without the involvement of the typical recycling steps (filtration, washing, and drying) for a solid recovery. Furthermore, when compared with a sonochemical process, the Z4A/PMS system was highly efficient and more selective for the degradation of both CIP in synthetic fresh urine and MO in simulated textile wastewater. This study offers relevant findings on the PMS activation toward the non-radical pathway using the zeolite 4A, which represents an interesting alternative to those materials composed of transition metals or carbonaceous structures, to treat organic pollutants in aqueous samples in a selective way.

Inhibition of Nickel (II) Mobility in Theobroma cacao L. Seedlings Using Zeolite 5A

In search of efficient solutions for the treatment of contaminated soils and in favor of the sustainable development of agriculture, this work aimed at developing an efficient method that helps to directly overcome the contamination by nickel in soils and Theobroma cacao L. seedlings. In this study, the genotypes ICS-39, CCN-51, and TSH-1188, which are high-yielding varieties in South America, were studied. The compound used as an adsorbent was commercial zeolite 5A. The zeolite 5A and soil samples were analyzed by X-ray diffraction, Raman microscopy, chemical analysis, electron microscopy techniques, and atomic absorption spectroscopy. This last technique was used for quantitative determination of Ni concentrations in seedlings. Zeolite 5A presented a high adsorption efficiency (95%) among the studied cacao genotypes, making this material a viable adsorbent and inhibitor agent of Ni. In addition, zeolite 5A was found to be not chemically harmful to the plant morphology (root and height), as demonstrated using statistical analysis. Finally, the Ni mechanism was described based on zeolite 5A physicochemical properties, suggesting that this material has remarkable soil remediation application.

A short review on recent advances in porous adsorbents for separation of oxygen from atmospheric air

AbstractPure oxygen demand is continuously increasing worldwide due to wide applications including medical and industrial. Pressure swing adsorption (PSA) is one of the promising techniques to separate O2 from atmospheric air. The porous solid adsorbent is a key element in the PSA to trap nitrogen (N2) and release O2. Several adsorbents including low silica X (LSX), zeolite 5A, ion‐exchanged LSX (Li‐LSX, AgLi‐LSX, Ca‐LSX), Engelhard titanosilicate (Na‐ETS‐10, Ag‐ETS‐10), and SSZ‐13 have been investigated for adsorption of N2 from the air. This review article is a summarization of recent research work published on O2 separation using different porous adsorbents via PSA. This review also emphasizes on the best porous sorbent for purification of O2 by sorption of N2 and Ar. The adsorption capacities with experimental conditions are also rigorously discussed. The review also proposed future trends and prospects for O2 separation. This review will be helpful to choose remarkable adsorbent for the generation pure O2.

Removal of RE3+, Cs+, Sr2+, Ba2+ from molten salt electrolyte by precipitation and solidification of glass-ceramics

Glass-ceramic is considered as a promising material for processing high-level radioactive waste. In order to treat the waste salt produced after electrolytic refining, the ceramics REPO4, Cs3PO4 and Ba0.6Sr0.4TiO3 were prepared. The analysis results indicated that RE and Cs were fixed in the ceramic lattice of REPO4 and Cs3PO4, and Sr and Ba were fixed in ceramic lattice of Ba0.6Sr0.4TiO3, the Cl− from salt was fixed in the lattice of sodalite. Phosphate ceramics had good heat resistance, and Ba0.6Sr0.4TiO3 a dense tetrahedral structure. These ceramics were jointly embedded in borosilicate and iron phosphate glass, respectively. The maximum embedding rate of mixture of salt containing ceramics and zeolite 4A in the two glass matrices could reach 30 wt.%. To investigated the stability of the two types of glass-ceramics, the leaching rate of each element was measured, which indicated that all elements had good leaching resistance on the 28th day.

CO2 methanation enhanced with a cyclic SERP process using a commercial Ni-based catalyst mixed with 3A zeolite as adsorbent

Valorization of greenhouse gas CO2 is needed to mitigate and reduce climate change impact. The sustainable production of methane to obtain synthetic natural gas (SNG) is one of the most attractive solutions, given current needs. The methanation reaction, known as the Sabatier reaction, is limited by the formation of CO as an intermediate at high temperatures and the formation of H2O as a by-product. For this reason, recent research has focused on the use of catalysts/adsorbents mixtures capable of retaining the water produced as well as being methane-selective at low temperatures. In this work, the kinetic model of a commercial Ni/SiAl catalyst in an experimental reaction bed was obtained. Moreover, the water adsorption capacity of the catalyst has been studied in the typical reaction temperature range (473–623 K), and the adsorption equilibrium and diffusional parameters were determined. With the data obtained from these experiments, the methane production in a cyclic Sorption Enhanced Reaction Process (SERP) has been simulated, adding zeolite 3A as a water selective adsorbent. The process consists of three consecutive stages: an adsorption/reaction stage and two other stages, rinse and purge, to desorb the adsorbed water and remove it by condensation. A sensitivity analysis has been carried out to determine the effect of the operational variables on the process performance to obtain methane suitable for domestic natural gas consumption. A CO2 conversion of 99.7 %, methane selectivity of 99.9 %, molar purity of CH4 of 98.2 % as product, and compression energy consumption (6.97 kJ/mol CH4) 99 times lower than methane combustion energy has been obtained, proposing, therefore, a new process of methanation.

In-situ release and sequestration of CO2 in cement composites using LTA zeolites

This paper investigates the impact of in-situ release and sequestration of CO2 on the compressive strength, volume of permeable voids, phase change, hydration reaction, and micro-morphology of cement mortars. Two Linde Type A (LTA) zeolites with micro-pore dimensions of 5 Å and 4 Å (i.e., LTA 5A and 4A zeolites) were employed as CO2 carriers herein. The incorporation of 312 wt% plain LTA 5A and 4A zeolites increases the 1-day compressive strength of the mortars. However, the use of plain LTA 5A zeolite shows marginal contributions to the 7 and 28-day compressive strengths of the mortars, whilst using plain LTA 4A zeolite even deteriorates their 7 and 28-day compressive strengths. The micro-structural analyses reveal that the addition of LTA zeolites promotes the cement hydration and improves the mean chain length (MCL) of calcium aluminosilicate hydrates (C-A-S-H). Nevertheless, this introduces numerous weak points or even a porous structure to the cement matrix. In contrast, in-situ release of CO2 via LTA zeolites significantly enhances the compressive strengths of the mortars at various ages, as this can further facilitate the hydration evolution and improve the MCL of C-A-S-H. Moreover, in-situ release of CO2 brings an incremental content of calcium carbonates. The calcium carbonate contents in the specimens containing 12 wt% LTA 5A and 4A zeolites are increased by 5.3 wt% and 4.8 wt%, respectively. This leads to homogenous distributions of calcite with a grain size of 150600 nm. Thus, LTA 5A zeolite outperforms LTA 4A zeolite with regard to CO2 uptake and the corresponding mechanical properties. This work presents in initial exploration into the application of porous pozzolanic materials in conjunction of CO2 in cement-based materials.

OBTAINING NEW MATERIALS BASED ON A COMBINATION OF SYNTHETIC ZEOLITES AND SILVER NANOPARTICLES

Nano silver has long been known as a highly effective disinfectant, capable of limiting the growth and eliminating many types of mold and bacteria. Nano silver can be synthesized by many different methods, depending on the purpose and requirements of use. Nano silver can be dispersed in solution or carried onto carriers for different applications. However, in solution, silver nanoparticles often tend to bind together, reducing antibacterial activity. In order to promote the antibacterial ability of nano silver and be able to recover and reuse many times, as well as to be able to disperse well into different materials, nano silver is often put on the carriers. In this study, nanosilver was synthesized on the surface of a zeolite by simple methods such as chemical reduction with NaBH4, N2H4 or thermal reduction at 350 °C. Ag+ ions are adsorbed onto 4A zeolite by ion exchange mechanism, then reduced by different methods. The materials were morphologically analyzed by XRD, SEM, EDX methods. Results showed that the method of reducing Ag+ to Ag0 on zeolite surface by chemical agent produce more evenly distributed silver nano-sized particles than the thermal reduction method. The silver content on the zeolite surface of the hydrazine reduction method is about 3 times higher than that of the sodium borohydride reduction method. The highest content of silver nanocarrying to zeolite. Zeolite bearing nano silver has the ability to disinfect against E.Coli with a concentration of ≥ 5 mg/ml. The Ag02/Z sample reducing Ag+ to Ag0 by Hydrazin has the best antibacterial ability against E.coli compared with the remaining samples when the diameter of the sterile ring at the concentration of 20 mg/ml is 9 mm. For citation: Xuan Minh Vu, Thi Lan Pham, Thi My Hanh Le, Thi Thu Hoai Pham, Chi Mai Nguyen, Dai Lam Tran Obtaining new materials based on a combination of synthetic zeolites and silver nanoparticles. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 3. P. 59-65. DOI: 10.6060/ivkkt.20236603.6722.

Multi-level computational screening of anion-pillared metal-organic frameworks for propane and propene separation

Although the search of proper adsorbents for efficient propane/propene (PA/PE) separation has attracted great interest, the actual process-level performance of adsorbents has been rarely considered as a filtering criterion. In this work, a multi-level computational screening of a database containing 936 anion-pillared metal–organic frameworks (AP MOF) is performed to identify promising adsorbents for practical PA/PE separation in pressure/vacuum swing adsorption (PVSA) processes. At the crystal level, the geometry properties are computed. The adsorption isotherms at the phase level are predicted via molecular simulations with the newly calibrated force field parameters. Based on the results from these two levels, 216 candidates are discarded. Then, referring to a rigorous 4-step PVSA model, a simplified batch adsorber model is proposed and used to efficiently identify qualified AP MOF candidates that can meet the separation requirements on PE purity (≥99.5 %) and a certain recovery. The screening indicates that 15 AP MOFs can be used to separate 15 %/85 % PA/PE feed gas with 80 % PE recovery. Only 2 out of them are feasible for the separation of 50 %/50 % feed with 75 % PE recovery. Finally, one of the best candidates is sent for rigorous PVSA process optimization. It shows that the screened adsorbent consumes less energy in the separation of 15 %/85 % PA/PE mixture compared with the benchmark 4A zeolite process. Clearly, this work is anticipated to provide an effective approach for the rapid screening of adsorbents for PA/PE separation in PVSA processes.

Simulation of gas-solid adsorption process considering particle-size distribution

• Population balance equation (PBE) is combined with particle-dependent adsorption kinetics equations to simulate gas-solid adsorption process on adsorbent with particle-size distribution. • Simulation results show that the adsorption behavior is significantly affected by the particle-size distribution of the adsorbent. • Approximation of particle-size distribution to volume-average size may lead to large underestimation of adsorption periods. The particle-size distribution of adsorbents usually plays an important role on the adsorption performance. In this study, population balance equation (PBE) is utilized in the simulation of an adsorption process to model the time-dependent adsorption amount distribution on adsorbent particles of a certain size distribution. Different adsorption kinetics model can be used to build the adsorption rate function in PBE according to specific adsorption processes. Two adsorption processes, including formaldehyde on activated carbon and CO 2 /N 2 /CH 4 mixture on 4A zeolite are simulated as case studies, and the effect of particle-size distribution of adsorbent is analyzed. The simulation results proved that the influence of particle-size distribution is significant. The proposed model can help consider the influence of particle-size distribution of adsorbents on adsorption processes to improve the prediction accuracy of the performance of adsorbents.

Study of 4A and 5A zeolite as a catalyst material in a catalytic converter for NO emission reduction in a CI engine.

The major contribution to atmospheric air pollution is from the heavy vehicular emission. At present, it is rising at an alarming rate. These automotive pollutions can be reduced to a great extent by the exhaust gas after-treatment methods. Among these, catalytic converter (CC) is the major source to reduce regulatory emission in the internal combustion (IC) engine. Most catalytic materials work in some specific temperature ranges, and they are also costly. In this study, the zeolite 4A (ZSM 4A) and zeolite 5A (ZSM 5A) powder were converted into a solid mold and tested as a catalytic material in the converter. The experimental readings were taken with the fabricated CC at the exhaust with various loads (0, 4, 8, 12, and 16kg) in the single-cylinder Kirloskar 5.2kW diesel engine. Waste plastics were pyrolyzed into oil and blended with diesel in the 50:50 ratio of diesel plastic blend (DPB) for this study. Nitrogen oxide (NO) and hydrocarbon (HC) were reduced by 18% and 22% respectively for ZSM 5A and 12% and 16% respectively for ZSM 4A.

Evaluation of the H2S and NO adsorption and release capacity of PEG-zeolites and PEG-titanosilicates composites

The exogeneous delivery of hydrogen sulfide (H2S) and nitric oxide (NO) has proven to have several therapeutic effects. However, the development of porous materials to be used as drug carries, specifically as carriers of gaseous molecules, is still in its infancy. In here, we synthesized and characterized four polyethylene glycol (PEG) composites obtained from two different kinds of zeolites (4A and Y) and two titanosilicates (ETS-4 and ETS-10). The H2S and NO adsorption capacities are important aspects of the H2S/NO carriers, and they were determined for all the PEG-composites. Additionally, release studies of the H2S/NO loaded composites in aqueous solution at physiological pH revealed a longer NO release than their parent material while for H2S this was not observed, yet the % of released H2S is higher than the parent material. Cytotoxicity studies using HeLa cell line showed that PEG composites at 450 μg/mL have no toxicity. The results indicate that all PEG composites may have potential as NO-carrier, while for H2S only the 4A@PEG may be evaluated.

One-step plasma reforming of CO2[sbnd]CH4 into hydrogen and liquid fuels: The roles of Cu and Fe sites on products distribution

Low-carbon plasma-catalysis technology has shown emerging potential for direct conversion of CO2/CH4 into H2 energy and value-added oxygenates at low temperatures. Nevertheless, how to efficiently regulate the distribution of the products and further reveal the catalytic roles of the active sites in plasma-catalysis remains a major challenge. Herein, we exploited 5A zeolite supported catalysts with varied Cu/Fe active sites and further investigated the effects of Ar/H2O additives in this reaction to tune the products distribution. Comprehensive characterization together with the evaluation tests revealed that Cu0 species in Cu/5A was favorable to the formation of CH3OH (18.0%), and Fe2+ in Fe/5A promoted the CH3COOH (7.9%) production. Noted that the addition of Ar greatly enhanced the conversions of CO2 (30.3%) and CH4 (55.6%) and the H2O additive significantly improved the H2 selectivity (56.6%). Upon systemic in-situ DRIFTS and kinetic modelling, the synergistic conversion routes involving the crucial radicals adsorption process over the catalysts surface were proposed. This work provides new insights into the design of highly selective catalysts for tuning the products distribution in the plasma-catalytic co-conversion of CO2/CH4.

Performance of zeolite- and PCM-based cascade hybrid heat accumulator with cast thermal conductivity enhancers

The study tackles the issue of facilitating heat transfer in a newly designed versatile thermal energy storage (TES) unit that uses waste or renewable energy. The novel hybrid heat storage unit, consisting of a phase change material (paraffin) and zeolite (4A) deposits to be used for short-term or long-term storage, was constructed and characterised. Cast aluminium heat transfer enhancers were designed, manufactured by 3D printing with investment casting and then applied in order to shorten the charging time and to equalise the temperature distribution in the accumulator. This approach ensured both the exceptional flexibility of the process and the easy optimisation of the heat transporting surfaces’ shape and weight, resulting in improved thermal behaviour without severely limiting the volume of the storage medium. Honeycomb-based perforated inserts were chosen as the most effective heat transfer geometries for both deposits. The performance of the hybrid heat storage unit was evaluated during an analysis of cyclic work’s. The theoretical values of heat efficiency and energy storage capacity were calculated as 65.7% and 2.63 kWh, respectively (2.29 kWh for the zeolite chamber and 0.34 kWh for the PCM one). Future work may deal with adjusting the connection between chambers (e.g. limiting heat losses).

Effects of the ion-exchange sequence on the CO2 uptake and CO2–over–N2 selectivity of zeolite NaKA

The CO2 and N2 adsorption on small-pore zeolite |Na12-xKx|-A was hypothesized to be affected by the ion exchange sequence used for the zeolite preparation. Zeolites were prepared by ion exchange of a commercially available zeolite |Na12|-A (4A) and a zeolite |K12|-A (3A) composition prepared from zeolite 4A. The CO2 and N2 adsorption properties were studied experimentally, and the binary CO2-over-N2 selectivity was estimated from single-component adsorption data using the apparent Henry's law coefficients. It was observed that the level of CO2 adsorption was reduced by increasing the K content for both series of zeolite NaKA. Zeolite |Na12-xKx|-A-from-4A had the highest CO2 adsorption capacity (at 1 atm and 273 K) for a given K content. At low K content, zeolite |Na12-xKx|-A-from-3A had the highest CO2-over-N2 selectivity. At an intermediate K content, the zeolites prepared from 4A had the highest selectivity. These differences show that non-equilibrium processes during the ion exchange are important for the CO2 and N2 adsorption properties of the derived zeolites. As of now, we refrain from speculating whether they relate to the detailed positioning of K+ and Na+ cations in the local structure of the zeolite or to mass-transport-related concentration gradients of the cations in the structure. Irrespectively, it was observed that the ion-exchange sequence affects the CO2 and N2 adsorption properties of the zeolites, which could be of general importance when it comes to the tuning of the properties of cation-rich zeolites.

Adsorption dynamics of ethane from air in structured fixed beds with different microfibrous composites

Adsorption dynamics of ethane in two granular fixed beds and structured fixed beds with microfibrous composites was studied. 5A zeolite membrane 5A/PSSF (paper-like sintered stainless steel fiber) and microfibrous entrapped activated carbon (MEAC) composites were prepared by wet layup papermaking/sintering technique and in-situ hydrothermal method. Microfibrous composites were characterized by X-ray diffraction, scanning electron microscopy and N2 adsorption/desorption. Structured fixed beds were designed by filling granular adsorbents (5A zeolite or activated carbon) and microfibrous composites at the inlet and outlet of the beds, respectively. Effects of flow rate, bed height and structure on the breakthrough curves were investigated. The length of unused bed (LUB) was determined, and Yoon–Nelson model was used to fit the breakthrough curves. The experimental results showed ethane was effectively adsorbed on the granular adsorbents and microfibrous composites. Both composites could decrease the LUB values and enhance bed utilization. All breakthrough curves fitted well to Yoon–Nelson model, with correlation coefficient exceeding 0.89. The adsorption rate of ethane could be improved in the structured fixed beds, which showed an enhanced mass transfer efficiency for ethane adsorption. LUB values of structured fixed beds with 5A/PSSF composites were larger, the bed utilization values were lower, and the adsorption rate constants were higher than those with MEAC composites under the same conditions.