Zeolite Y Research Articles

Zeolite-coated 3D-printed gyroid scaffolds for carbon dioxide adsorption

3D-printed adsorbents are gaining increased attention owing to their potential in overcoming operational challenges faced by the conventionally structured counterparts. In this work, cylindrical scaffolds of triply periodic minimal surface (TPMS) configuration were synthesized using 3D-printing by stereolithography. This unique gyroid sheet TPMS network was selected as it offers a high surface-area-to-volume ratio. The surface of the scaffolds was modified by a silanization process followed by coating via grafting with zeolite 13X crystals toward CO2 adsorption application. A secondary zeolite coating step was also employed to enhance the zeolite 13X loading, resulting in zeolite loadings of 16 wt% and 23 wt% after the primary and secondary coatings, respectively. Following morphological and structural characterization, the CO2 adsorption performance of the 3D-printed materials was evaluated with respect to adsorption capacity, kinetics, selectivity, and heat of adsorption. Cyclic stability was also assessed over CO2 adsorption–desorption pressure swing adsorption cycles at 25 °C. Comparative analysis showed that the 3D-printed coated samples exhibited higher CO2/N2 selectivity and improved cyclic stability with a slightly lower CO2 adsorption capacity than the zeolite 13X powder. The heat of adsorption ranged from 18 to 41 kJ mol−1 for both the powder and the coated adsorbents, indicating physisorption. The gyroid lattice of the 3D-printed structures, featuring a densely arranged network of smooth, interconnected flow channels, facilitated molecular transport thus yielding higher CO2 adsorption kinetics than the powder. Indicatively, the primary and secondary coatings attained an equilibrium capacity of 4 mmol g−1 at 25 °C in 62 and 57 min, respectively, while the powder required 110 min at the same conditions. The 3D-printed materials exhibited also significantly higher CO2/N2 selectivity values of 569 and 115 at 50 mbar and 1 bar, respectively, for the primary coating sample, and 536 and 73 at 50 mbar and 1 bar, respectively, for the secondary coating one. The findings highlight the potential of 3D-printing to produce coated structured adsorbents with complex geometries for sustainable CO2 capture and gas adsorption processes.

Ethanol-enhanced wash-coating of zeolite 13X on microchannel walls for CO2 capture

Minimizing the energy demand for capturing carbon dioxide (CO2) from air and post-combustion sources is critical to mitigate the effects of climate change. Adsorbent-coated microchannels have been shown to significantly enhance the performance of CO2 capture systems. A novel single-dip wash-coating approach is developed in this work using silica nanoparticles and various base solvents to create a uniform and porous zeolite 13X adsorbent layer on cordierite microchannels. Extensive exploration of base solvents is undertaken to enhance adsorption performance and structural integrity, culminating in identifying a 70 % ethanol mixture as the most effective solvent. The coatings are characterized through a materials characterization suite and image analysis in conjunction with CO2 adsorption performance to determine the optimum adsorbent loading conditions. Equilibrium adsorption performance tests are performed for the coated samples in CO2 capture systems. The specific surface area (SSA) of the powdered 13X, initially measured at 662 m2/g, decreased to 553 m2/g in the coated form (utilizing a 20 % solid fraction with 70 % ethanol as the solvent), which is consistent with the observed adsorption performance results. The results underscore the scalability potential of these coated microchannels, presenting a promising alternative for CO2 separation systems to the conventional packed adsorbent beds.

An experimental comparison of thermal energy storage in directly and indirectly radiated adsorbent beds integrated with solar thermal collectors

AbstractAdsorbents heated using solar energy can be used to achieve thermal energy storage and sorption refrigeration with low environmental impacts. This research compares two different methods of heating adsorbents with solar energy to store thermal energy: (1) by exposing the adsorbents to incident light transmitted through a solar collector window, and (2) by heating a highly absorbing solar collector cover, and then transferring the heat from this solar absorber to adsorbents located beneath it. To carry out this comparison experiments are conducted for three cases of adsorbent beds using zeolite 13X and water as the adsorbent‐adsorbate pair. In the first case, the top of the adsorbent bed is a polycarbonate sheet, and the zeolites are heated directly by solar‐simulated light transmitted through this sheet. In the second case, a blackened aluminum sheet is placed beneath the polycarbonate sheet to generate heat by absorbing incident light. For the third case, the blackened aluminum absorber is placed directly on top of the zeolite beads and the absorber is isolated from the walls of the reactor to avoid heat losses. The outcomes reveal an energy storage density (ESD) of 43.6 kWh/m3 (63.4 Wh/kg) when light is directly incident onto the zeolite 13X and an ESD of 33.3 kWh/m3 (48.4 Wh/kg) when light is incident onto a blackened absorber plate that transfers heat to Zeolite beads residing beneath it. However, ESD values were improved to 48.9 kWh/m3 (71.0 Wh/kg) when the blackened absorber plate was thermally insulated from the walls of the adsorbent bed. These results demonstrate the importance of an optimal absorber arrangement in enhancing the adsorption process for the purpose of elevating energy storage densities.

Fabrication of sphere adsorbent materials based on zeolite 13X, application in household oxygen concentrators

Fabrication of sphere adsorbent materials based on zeolite 13X, application in household oxygen concentrators

Dechlorination of a real plastic waste pyrolysis oil by adsorption with zeolites

The adsorptive dechlorination of a pyrolysis oil coming from real plastic waste was investigated using different Na-zeolites (4A, 13X, and Y) as adsorbents. The dechlorination experiments were performed in a fixed bed trap under inert atmosphere operating at moderate temperatures (< 180 °C). The dechlorination efficiency of the adsorbents was significantly improved by performing a dehydration pre-treatment due to the removal of water molecules physisorbed on the zeolite surface. Among the zeolitic materials tested, 13X zeolite showed the best dechlorination efficiency, which was related to its high content of Lewis acid sites (attributed to the presence of Na+ cations ionically interacting with the zeolite framework), acting as chemisorption sites, as well as the high accessibility of the FAU-zeolitic topology to the Cl-containing compounds. For that sample, a detailed study of the adsorption temperature (from 30 to 180 °C) and time on stream (1–6 h) was further carried out. The maximum chlorine removal efficiency was achieved, reducing the chlorine content of the pyrolysis oil from 421 to 45 ppm, at temperatures of about 150 – 180 °C. Interestingly, under these conditions, thermal or catalytic cracking effects of the zeolite on the feedstock were not observed. However, the study of the time on stream showed that, after 3 h, the chlorine removal efficiency of the zeolite started to decrease. Thus, different regeneration treatments were evaluated proving that, after a combustion at 600 °C, the zeolite recovered its initial dechlorination efficiency. This research reveals the potential of the adsorptive dechlorination process with Na-zeolites to reduce the chlorine content in plastic pyrolysis oils under mild operating conditions.

High capacity laminate adsorbers: Enhancing separation performance beyond packed beds

In response to the growing demand for more efficient adsorption processes, structured adsorbents have emerged as a promising solution as they offer improved mass transfer and pressure drop characteristics. However, they are often hampered by a lower volumetric capacity due the presence of support structures or a large bed void fraction. This research focuses on the manufacturing and evaluation of self-standing zeolitic laminates of various thickness and spacing, comparing their performance to a traditional packed bed. A shaping method to obtain laminates with a 84 wt% zeolite 13X content is described. Furthermore, a method for precise assembly and spacing of the laminates is detailed. Three such laminar adsorbers with different geometries were evaluated in breakthrough experiments and compared to a packed bed to assess their efficiency in the bulk separation of carbon dioxide. Superior performance of the laminar adsorbers was found, with one configuration employing 1.2 mm laminates and 0.4 mm spacing showing a significant 19 % increase in volumetric capacity compared to a packed bed of pellets. This enhanced capacity is achieved while maintaining efficient heat and mass transfer, resulting in sharp breakthrough profiles. Furthermore, using thinner (0.5 mm) laminates, the length of unused bed was further reduced. Additionally, pressure drop calculations were performed and experimentally validated. The pressure drop over the laminar adsorbers was shown to be significantly lower than over a packed bed. These findings underscore the potential of laminar adsorbers to intensify adsorptive separation processes, reduce energy consumption, and address the demand for more effective adsorption technologies.

Experimental Testing System for Adsorption Space Heating

Approximately 40 % of the final energy is used for heating and cooling of buildings. Of this, as much as 75 % is used in residential buildings. The proportion of energy needed in buildings is relatively high, so it is necessary to start using technologies that have low energy consumption, use it efficiently or provide it from renewable sources. One such technology is thermal energy storage, which allows us to store excess energy for later when we need extra energy. The paper presents two experiments in the field of adsorption space heating. In the first experiment, measurements were carried out on the adsorbents - zeolite 13X and zeolite NaYBFK, which were placed into a duct, through which humid air was transported by means of a centrifugal fan. In the second experiment, water vapour as the working medium was used. With the first experiment we achieved better water uptake on NaYBF, while the second experiment shows the increase of water uptake of zeolite 13X.

Concentration of stigmasterol, β-sitosterol and squalene from passion fruit (Passiflora edulis Sims.) by-products by supercritical CO2 adsorption in zeolite 13-X

Phytosterols and squalene, widely applied in pharmaceutical and food industries, were extracted and concentrated from passion fruit by-products (PFBP). A supercritical extraction using CO2 (SFE) was performed for PFBP, and the obtained extract underwent supercritical fractionation (SFA) (inlet at 35 MPa, 50–70 ℃) in a column packed with zeolite 13-X (5–15 g). The extraction and fractionation yields were measured, whereas the composition of the PFBP extract and their fractions was assessed by gas chromatography-mass spectrometry (GC-MS). Fractionated extract recovered presented different trends depending on temperature and zeolite mass combinations, and the highest recovery (approximately 95%) was achieved at 50 ºC with 15 g of adsorbent. At the same SFA conditions, the concentration of squalene, β-sitosterol and stigmasterol was twice that obtained in PFBP extract. Finally, SFA proved to be a clean and effective technique to concentrate squalene and phytosterols from PFBP, which should be extended to other food residues.

Impact of varied zeolite materials on nickel catalysts in CO2 methanation

Ni catalysts supported on 4A, 5A, 13X, ZSM-5, and BEA zeolites were prepared using the vacuum-heating method for CO2 methanation. These support materials play a pivotal role in shaping the catalysts' properties and their catalytic performance. High-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDS) mappings suggest a significant concentration of Ni nanoparticles situated on the external surfaces of catalysts with low Si/Al ratios zeolites (Ni-4A, Ni-5A, and Ni-13X). These Ni nanoparticles exhibit characteristics of weaker metal-support interaction, lower metal reduction temperatures, and moderate H2 adsorption activity. Moreover, these low Si/Al ratio zeolites demonstrate robust CO2 adsorption activity. These properties endow Ni-5A and Ni-13X catalysts with heightened CO2 conversion (70.4–70.9%) and methane selectivity (92.4–96.4%). In contrast, high Si/Al ratio zeolite-based catalysts (Ni-ZSM-5 and Ni-BEA) exhibit smaller Ni particles, strong metal-support interaction and weaker CO2 adsorption activity, resulting in reduced CO2 methanation activity and decreased methane selectivity (71.2–73.4%). The normalized CO2 conversion rate presents a correlation with the average Ni particle size.

Experimental microwave assisted CO2 desorption of a solid sorbent in a fluidized bed reactor

In this study, a novel method has been applied to regenerate CO2 from a solid sorbent (Zeolite 13X) using a mono-mode microwave unit under fluidization conditions. Several parameters have been varied to investigate their effect on the desorption characteristics as well as on the energy consumption. While flow rate varied between 200 Nml/min to 1,000 Nml/min, regeneration temperature changed from 40 °C to 100 °C. Microwave initial forward power also varied from 15 W to 30 W.Volumetric heating of microwave led to desorption of CO2 from the sorbent effectively while fluidization enhanced the heat transfer within the sorbent by providing homogeneous heat transfer with lower desorption time and absorbed energy. The most dominant parameters on the desorption time and energy consumptions were found to be flow rate and regeneration temperature, respectively. Under different conditions, the energy consumptions to regenerate a kg CO2 varied between 2.84 MJ and 27.17 MJ. Even though the lowest energy consumption was obtained when the flow rate was 200 Nml/min at 40 °C; the time for a complete desorption found to be quite high with this flow rate. Therefore, a minimum energy consumption of 3.87 MJ/kg CO2 within a short period of regeneration time can be achieved under the fluidization regime with the flow rate of 1,000 Nml/min at 40 °C. While an increase in the flow rate also caused a slight increase in the energy consumption for low regeneration temperatures, it resulted in a significant decrease under higher regeneration temperatures. Furthermore, the main drawback of low flow rate conditions is that most of the energy was consumed to remove the last 10 % of CO2 from the sorbent. Therefore, fluidization plays a significant role on the removal of CO2, especially between the 90 % and 100 % regeneration percentages.This work is the first study in the literature that has investigated the effects of fluidization on the desorption characteristics of CO2 under mono-mode microwave conditions. It was proved that fluidization reduced the energy consumption of CO2 desorption with higher microwave efficiency.

Preparation and thermal properties of zeolite 13X/MgSO4-LiCl binary-salt composite material for sorption heat storage

Thermal energy storage can play a pivotal role in waste heat recovery and solar energy thermal utilization by balancing the time and space-mismatch between supply and demand of energy. Thermochemical sorption heat storage technology has gained the enormous interest for its ability to make use of the low-grade thermal energy. However, the slow sorption reaction kinetics of sorbents remains an obstacle for the large-scale industrial applications of thermochemical sorption heat storage technology. In this study, a new type of zeolite 13X/MgSO4-LiCl composite sorbent material has been fabricated by impregnating zeolite 13X with the mixed solution of MgSO4 and LiCl. The structural characteristics and sorption heat storage performance of composite adsorbents with different mass ratios of MgSO4 and LiCl were studied experimentally by scanning electron microscopy (SEM), full-automatic specific surface area and pore analyzer (ASAP), and thermogravimetry analysis-differential scanning calorimetry (TGA-DSC). The results indicate that binary-salt sorbents show the faster sorption kinetics and higher water sorption capacity compared to single salt sorbents. When the mass ratio of MgSO4 and LiCl is 2:1, the zeolite 13X/MgSO4-LiCl composite sorbent (XML-2/1) has the best sorption heat storage performance. Under the sorption temperature of 25 °C and relative humidity (RH) of 60 %, the maximum sorption capacity is 0.24 g/g, and the corresponding heat storage density of 458.3 kJ/kg can be achieved. The results indicate that the zeolite 13X/MgSO4-LiCl composite adsorbent can improve the sorption rate and heat storage density. Compared with pure zeolite 13X and zeolite 13X/MgSO4 composite sorbents, the addition of LiCl can effectively improve the sorption rate and sorption heat storage capacity. The findings of this investigation could promote the growing body of research on the mixed salt (binary-salt or multiple-salt) composite materials and new insights can be offered by broadening the application of zeolite-based composite materials in low-grade thermal energy storage for space heating, which can guide further research and development in this field and ultimately help facilitate the transition toward the clean energy.

Tuning selectivity of acetic acid and alcohols by Brønsted and Lewis acid sites in plasma-catalytic CH4/CO2 conversion over zeolites

Plasma catalysis enables CH4/CO2 direct conversion to oxygenates under mild conditions. However, addressing complexity of oxygenate products is the main scientific challenge. Herein, the roles of Brønsted and Lewis acid site (i.e., BAS and LAS) in tuning the selectivity of acetic acid and alcohols have been comparatively investigated for the first time. BAS and LAS are provided by HZSM-5 and 13X zeolites, respectively, and their amounts are adjusted by steam treatment. Results reveal that BAS significantly promotes acetic acid formation, while LAS favors alcohols generation. In addition, Au supported zeolites show that Au3+-BAS synergy exhibits potential for acetic acid. In-situ FTIR spectra identify the bicarbonate (HCO3,ad) and formate (HCOOad) to be the primary surface species on BAS and LAS, respectively. Correspondingly, the pathways for acetic acid and methanol production are proposed based on catalyst characterizations and plasma diagnosis. This work opens up zeolite-based catalysts for selective CH4/CO2 conversion to oxygenates.

A Kinetic Study of Microwave‐Assisted Desorption of Co2 from Zeolite 13x

CO2 is the main contributor of the greenhouse gas emission which considerably accelerates climate change. The capture of CO2 requires the development of sustainable adsorption‐desorption processes, which can be upscaled to satisfy the industrial demands. It is well‐known that sustainable microwave (MW) heating leads to fast desorption of CO2 compared to conventional, but there is a lack of study on how to upscale this process. Here it is investigated a concept for the upscaled multi‐mode MW heating of zeolite 13X. The proposed concept is based on the non‐isothermal kinetic study of CO2 desorption, revealing a complex multi‐step process: activation of zeolite 13X below 40 °C and CO2 desorption at T &gt; 40 °C with Eact = 0 kJ mol−1. It was found that MW‐assisted CO2 desorption happens simultaneously with H2O desorption after zeolite MW‐activation. The mechanism of MW‐assisted desorption of CO2 has been proposed. Based on this mechanism, the parameters important for optimizing CO2 desorption process at a larger scale are offered together with an upscaled concept.

Zeolite 13X incorporated with Zn-Ce oxide nanocatalyst for removal of Reactive Red 120 dye: RSM-based approach.

In this study, the photocatalytic removal of Reactive Red 120 (RR120) dye was examined using zeolite 13X incorporated with Zn-Ce under UV irradiation. The synthesis of Zn-Ce nanoparticles incorporated with zeolite 13X was conducted through the co-precipitation method, and the features of the prepared nanocatalyst were analyzed using various techniques. The SEM and BET analyses indicated successful incorporation of ZnO-Ce oxides on the surface of zeolite 13X and a specific surface area of 359.39 m2/gm, respectively. Further, the average size of crystal grains was 28 nm. The response surface methodology (RSM) approach was employed to optimize operating parameters. The quadratic model suggested by the RSM approach, characterized by a high regression coefficient (R2 = 0.9632), indicates a high level of reliability. Moreover, under optimal conditions (catalyst loading of 4 mg, pH of 3, H2O2 amount of 0.2 mL, UV power of 25 W, and reaction time of 60 min), the highest RR120 dye removal percentage was 99.97%. Kinetic data indicated an increase in the reaction rate constant from 0.0631 to 0.1796 min-1. The zeolite 13X incorporated with Zn-Ce photocatalyst exhibited excellent stability over 5 cycles, with only a 5.50% decrease in RR120 dye removal yield. This study demonstrates the promising potential of zeolite 13X incorporated with Zn-Ce nanoparticles for the removal of RR120 dye from aqueous suspension.

Preparation and thermal properties of zeolite/MgSO4 composite sorption material for heat storage

Thermochemical sorption heat storage based on salt hydrates offers the potential advantages such as high energy density, negligible heat loss, small volume change and flexible working modes. Magnesium sulphate (MgSO4) is a high energy density hydrated salt available for the thermochemical sorption heat storage. In this work, different types of zeolites (including 3A, 5A and 13X zeolites) have been selected as mass-transfer-enhancing and structural stabilizing materials, and a series of zeolite/MgSO4 composites have been fabricated. To investigate the thermal energy storage performance of zeolite/MgSO4 composites, the properties of the composites, such as micro-morphology, pore structure, chemical composition and sorption-desorption behavior, have been characterized and analyzed. Results indicated that the mass transfer performance of the composite materials is significantly better than that of the pure zeolites. As the mass fraction of MgSO4 in the composite sorbents increases, the specific surface area and porosity of the composite sorbent decreases, and the sorption performance has been enhanced. Compared with 3A zeolite-based and 5A zeolite-based composites, 13X zeolite/MgSO4 composite materials show the best heat storage performance. At the condition of 25 °C and 60% RH, the 13XM20 has the highest sorption capacity of 0.21 g/g, which is 24% higher than that of pure zeolite 13X. Accordingly, the maximum heat storage density is 438.4 kJ/kg, which exhibits the superior heat storage performance among of the hydrated salt sorbents. The potential of 13X zeolite/MgSO4 as sorption heat storage material in efficient utilization of solar heat and low-grade industrial waste heat has been revealed.

Statistical analysis of parameters and adsorption isotherm models.

The present work intends to discuss parameter estimation and statistical analysis in adsorption. The Langmuir and Tóth isotherm models are compared for a set of carbon dioxide adsorption data on 13X zeolite from literature at different temperatures: 303, 323, 373, and 423 K. Statistical analyses were performed under frequentist and Bayesian perspectives. Under the frequentist statistical view, parameters were estimated using Maximum Likelihood estimation (MLE). Statistical analyses of parameters were performed by confidence regions in terms of elliptical approximation and likelihood region, while the evaluation of models was performed by chi-square statistics. The results showed that, for these nonlinear models, the elliptical region offers a poor approximation of the parameter estimates' confidence region, especially for the most correlated parameter pairs. Additionally, the four-parameter Tóth's equation yields less correlated parameters than the three-parameter Langmuir model. From a Bayesian perspective, the Markov chain Monte Carlo (MCMC) technique facilitated the reconstruction of the probability density functions of parameters as well as enabled the propagation of parametric uncertainties in the model responses. Finally, the accurate assessment of experimental uncertainty significantly influences the evaluation of models and their respective parameters.

Synthesis and Structural Analysis of High-Silica ERI Zeolite with Spatially-Biased Al Distribution as a Promising NH3-SCR Catalyst.

Erionite (ERI) zeolite has recently attracted considerable attention for its application prospect in the selective catalytic reduction of NOx with NH3 (NH3-SCR), provided that the high-silica (Si/Al > 5.5) analog with improved hydrothermal stability can be facilely synthesized. In this work, ERI zeolites with different Si/Al ratios (4.6, 6.4, and 9.1) are synthesized through an ultrafast route, and in particular, a high-silica ERI zeolite with a Si/Al ratio of 9.1 is obtained by using faujasite (FAU) as a starting material. The solid-state 29Si MAS NMR spectroscopic study in combination with a computational simulation allows for figuring out the atomic configurations of the Al species in the three ERI zeolites. It is revealed that the ERI zeolite with the highest Si/Al ratio (ERI-9.1, where the number indicates the Si/Al ratio) exhibits a biased Al occupancy at T1 site, which is possibly due to the presence of a higher fraction of the residual potassium cations in the can cages. In contrast, the Al siting in ERI-4.6 and ERI-6.4 proves to be relatively random.

Synthesis of zeolite molecular sieve 13X from coal-fired slag for efficient room temperature CO2 adsorption

Coal-fired slag (CFS) was used to successfully synthesize zeolite molecular sieve (ZMS) 13X by the alkali fusion hydrothermal method for efficient room-temperature CO2 adsorption. The optimum synthesis conditions of ZMS 13X were confirmed using the single-factor and Box-Behnken methods. With a specific surface area of 585.67 m2·g−1, the resultant ZMS 13X is a mesoporous material with good CO2 adsorption selectivity and cyclic performance. At 25 °C and 1 bar, the initial CO2 adsorption amount presented 3.69 mmol·g−1 and still maintained 3.37 mmol·g−1 of CO2 adsorption amount after 10 cycles. The Langmuir isotherm model can well describe the CO2 adsorption process of ZMS 13X as an entropy-decreasing physical adsorption process with the intermolecular interaction of van der Waals forces. Therefore, this work proposes a new strategy for the low-cost synthesis of ZMS 13 from the CFS solid waste for efficient room-temperature CO2 capture.

Desorbent swing adsorption process using ethylene to separate propane and propylene under isobaric conditions

The separation of olefin and paraffin using adsorption technology remains a significant challenge. This study proposes a novel desorbent swing adsorption (DSA) process using an olefin desorbent with a weaker adsorption affinity (C2: ethylene) to separate a paraffin/olefin mixture with a higher adsorption affinity (C3s: propane and propylene) under isobaric conditions, which is the reverse concept of using a desorbent with a stronger affinity in conventional DSA systems. The proposed DSA process effectively separates the C3 mixture because the deteriorating effects caused by the desorbent is minimized. Based on sequential breakthrough experiments with zeolite 13X DSA using ethylene, the efficient separation of a propylene dehydrogenation product (propane:propylene = 60:40 vol%) to produce polymer-grade propylene is achieved. It is confirmed that ethylene desorbent stream pushes out the adsorbed propylene and regenerates the adsorption bed without changing the pressure. The desorption step plays a key role in the separation performance of the proposed DSA process because the regenerated bed offers favorable conditions when filled with the weaker desorbent after the desorption step. The flowrate of the desorbent strongly affects the efficiency of propylene desorption. After validating the dynamic mathematical model using the experimental results, a two-bed DSA process using a six-step sequence that includes rinse export/import and idle steps is shown to achieve a propylene purity above 99.999 % (desorbent-free basis) with a recovery of 99.39 %, a productivity of 4.21 mol∙kg−1∙hr−1, and an ethylene usage of 7.59 mol∙kg−1∙hr−1. This study offers important insights into the development of adsorptive separation designs for olefin/paraffin separation.

Scaling up 3D printed hybrid sorbents towards (cost) effective post-combustion CO2 capture: A multiscale study

A 3D-printed sorbent containing polyethylene-imine and multi-walled carbon nanotubes (PEI-MWCNT) was studied for post-combustion carbon capture. In this work, the adsorbent was printed on a kg scale and characterized for CO2 adsorption through lab experiments. A 6-step VSA process was simulated using the lab data to capture CO2 from a representative 800 MW power plant. The adsorbent captured >70 % of the CO2 and 95 % CO2 purity was achieved. The levelized cost of electricity (LCOE) was 130.2 $/MWh and the costs of CO2 captured and avoided were 80 and 100.12 $/tonne. However, a zeolite 13X-activated carbon (13X-AC) monolith achieved a lower LCOE of 118.1 $/MWh, with the captured and avoided costs being 63 and 78.4 $/tonne, respectively. The LCOE value for the 13X-AC monolith was 5.1 % lower than a reference-packed bed system with Zeolite 13X pellets. The corresponding cost values were lower by 9.1 % and 13.9 %, respectively for the costs of CO2 captured and avoided. The lab experiments on the PEI-MWCNT sorbent revealed that further work is necessary to improve the thermal stability and stability with long-term storage of the precursor paste.