02028nas a2200181 4500008004100000022001400041245009800055210006900153260000800222300001400230490000700244520137000251100002401621700002801645700002201673700002601695856012501721 2023 eng d a0021-956800aEquilibrium adsorption of nitrogen, oxygen, and argon on silver-exchanged hierarchical ETS-100 aEquilibrium adsorption of nitrogen oxygen and argon on silverexc cJUL a2159-21720 v683 a

Silver-exchanged hierarchical ETS-10(Ag-H-ETS-10) was synthesizedusing Ag+ exchange with hierarchical Engelhard titanosilicate(H-ETS-10) using silver nitrate solution. The physical propertiesof the adsorbent were analyzed using X-ray diffraction (XRD), BETsurface area, nitrogen adsorption-desorption, pore volume,energy dispersive spectroscopy (EDS), and high resolution-transmissionelectron microscopy (HR-TEM). N-2 physisorption data confirmedthat a micro-mesoporous (bimodal) structure was created in the Ag-H-ETS-10.The equilibrium adsorbent data of pure gases N-2, O-2, and Ar were investigated in the temperature range from 288to 318 K up to 10 bar. The equilibrium adsorption capacity of Ag-H-ETS-10was found to be 1.12 mmol g(-1) for N-2,0.87 mmol g(-1) for O-2, and 1.09 mmol g(-1) for Ar at 298 K and & SIM;10 bar. & SIM;20% higheradsorption capacity was found for N-2 and Ar in Ag-H-ETS-10compared to Ag-ETS-10. The higher sorption capacity was attributedto the formation of a bimodal structure and & pi;-complexation interactionby the Ag cation, which allows a multilayer of N-2 and Armolecules. The Sips isotherm model was well fitted for the Ag-H-ETS-10experimental data among Langmuir, Freundlich, Toth, and Temkin models.The measured equilibrium adsorption data for Ag-H-ETS-10 can be usefulfor the O-2 purification process.

1 aShrotri, Aadesh, R.1 aNiphadkar, Prashant, S.1 aBokade, Vijay, V.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/equilibrium-adsorption-nitrogen-oxygen-and-argon-silver-exchanged-hierarchical-ets-1002014nas a2200241 4500008004100000245006700041210006700108260000800175300001100183490000700194520127900201653001501480653001901495653002001514653001701534653002001551653001301571100001901584700002401603700002001627700002601647856009901673 2024 eng d00aContinuous flow synthesis of hierarchical low silica X zeolite0 aContinuous flow synthesis of hierarchical low silica X zeolite cJUN a1090470 v393 a

Zeolites, renowned for their versatile applications in catalysis, adsorption, and ion exchange, have long been synthesized using conventional batch processes. However, the inherent limitations of these methods, such as resource-intensive conditions and inconsistent product quality, underscore the need for a sustainable and efficient approach. In this study, a continuous flow synthesis process was established for the synthesis of industrially important low silica X (LSX) zeolite using a tubular reactor. The synthesis gel was subjected to aging for 5 days at room temperature to facilitate nucleation and crystal growth combined with the fast-heating rate in a tubular reactor at 363 K & 1.1 atm., which in turn produces LSX after 40 min. The synthesized product was confirmed by the XRD, FE-SEM, EDS, XRF, TEM, and N2 adsorption-desorption; the data was compared with the LSX sample synthesized by batch process. The result implies that LSX prepared by continuous flow has a pure phase of LSX with the hierarchical structure, which provides better adsorption capacity of CO2 at 298 K up to 20 bar. Due to continuous flow synthesis, the crystallization time was reduced and faster kinetics which may be helpful for scale-up the process for LSX synthesis.

10aAdsorption10aCarbon dioxide10acontinuous flow10aLow silica X10aTubular reactor10azeolites1 aAdarsh, V., K.1 aShrotri, Aadesh, R.1 aBirje, Amit, R.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/continuous-flow-synthesis-hierarchical-low-silica-x-zeolite02167nas a2200265 4500008004100000022001400041245009100055210006900146260000900215300001200224490000800236520130800244653001501552653001901567653001301586653002701599653001501626100002401641700002001665700002801685700002201713700002101735700002601756856011901782 2024 eng d a1226-086X00aPerformance of Li exchange hierarchical X zeolite for CO2 adsorption and H2 separation0 aPerformance of Li exchange hierarchical X zeolite for CO2 adsorp cMAY  a505-5140 v1333 a

Li exchange hierarchical X zeolite (Li-H-X) was prepared by decationization of X zeolite by NH4Cl solution followed by Li exchange and subsequent calcination. NH4-X and Li-X were prepared to compare the results of LiH-X. XRD, FE-SEM, EDS, N2 adsorption-desorption, and micro-/mesoporous volume were performed. The higher mesoporosity was confirmed in Li-H-X due to the framework dealumination during decationization. Static and dynamic sorption capacity of sorbents was evaluated to identify the performance of sorbent. The CO2 and H2 equilibrium adsorption capacity of Li-H-X was found to be 9.6 mmol g-1 and 0.78 mmol g-1, respectively, at 298 K and 20 bar, which was 25 % (CO2) and 30 % (H2) higher than Li-X. Static experimental data were validated using the Langmuir, Freundlich, and Sips models. The CO2 & H2 dynamic sorption capacity of Li-H-X sorbent for binary gas (CO2/H2, 25/75 %) was 4.145 mmol g-1 and 0.258 mmol g-1 at 303 K and 10 bar. The higher sorption capacity of Li-H-X was obtained due to large micro-/mesoporous volume of sorbent, which may allow to access unoccupied sites at higher pressure. This result reveals that micro-/mesoporous structure of zeolite adsorbs significantly higher CO2 from binary gas stream, which can use to separate pure H2 from gas stream.

10aAdsorption10aCarbon dioxide10aHydrogen10aMicroporous-mesoporous10aSeparation1 aShrotri, Aadesh, R.1 aBirje, Amit, R.1 aNiphadkar, Prashant, S.1 aBokade, Vijay, V.1 aMali, Nilesh, A.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/performance-li-exchange-hierarchical-x-zeolite-co2-adsorption-and-h2-separation02375nas a2200241 4500008004100000022001400041245011000055210006900165260000900234300001200243490000700255520154900262653001401811653002301825653002601848653001101874653002301885653003001908100002401938700002001962700002601982856012502008 2024 eng d a0360-319900aPressure swing adsorption of Li exchange hierarchical X zeolite for pure hydrogen from binary gas mixture0 aPressure swing adsorption of Li exchange hierarchical X zeolite  cJUL  a138-1470 v733 a

This study reports the separation of pure hydrogen (H2) employing pressure swing adsorption (PSA). The Li-X and Li-hierarchical X (Li-H-X) zeolite were prepared by an ion exchange process. The sorbents were evaluated through several experiments including, breakthrough, empty bed contact time (EBCT), single-bed, and two-bed PSA with different steps. The effect of pressure, purity, and recovery relationship was developed. The highpressure PSA study was performed at 4, 6, and 10 bar with varying feed flow rates to assess their efficacy in pure H2 separation using binary gas stream (H2/CO2, 75/25 vol.%). The breakthrough adsorption capacity of Li-H-X exhibited 3.4 mmol g-1 and 0.212 mmol g-1 of CO2 and H2, respectively. Li-H-X shows -8% higher CO2 sorption capacity than the Li-X sorbent at 1 bar and 300 K due to the large meso-microporous structure of the sorbent. The two-bed PSA purity and recovery were found higher than single-bed PSA. Using two-bed PSA, the Li-H-X achieved a 99.5% of purity, 92.9% of recovery, and 10.4 mL min-1 g-1 of productivity, which was -16% higher recovery and productivity than single-bed PSA at a flow rate of 1200 mL min-1 at 6 bar. With increasing the pressure and flow rate, the recovery of Li-H-X was enhanced up to 93.7% with 99.1%-99.9% H2 purity. The long-term PSA was run using Li-H-X sorbent for 7.5 h with 230 cycles with H2 purity between 98.5 and 99.5% at 6 bar. Interestingly, the adsorbent shows the scalability of PSA for efficient H2 separation for a binary mixture of H2/CO2.

10aadsorbent10aBinary gas mixture10aHydrogen purification10aLi-H-X10aMesoporous zeolite10aPressure swing adsorption1 aShrotri, Aadesh, R.1 aBirje, Amit, R.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/pressure-swing-adsorption-li-exchange-hierarchical-x-zeolite-pure-hydrogen-binary-gas02358nas a2200313 4500008004100000022001400041245014700055210006900202260000900271300001200280490000800292520132300300653001501623653001101638653001601649653001201665653000801677653001501685100002201700700002401722700002301746700002001769700002801789700002101817700002601838700002201864700002601886856013201912 2025 eng d a1226-086X00aBinderless low silica X zeolite for methane separation from binary CO2/CH4 biogas stream: A comprehensive experimental and computational study0 aBinderless low silica X zeolite for methane separation from bina cSEP  a705-7190 v1493 a

This study presents the synthesis of binderless Na-LSX (B-Na-LSX) and binderless NaK-LSX (B-NaK-LSX). XRD, SEM, EDS, and N-2 physisorption were used for characterization of samples. Computational modelling of prepared sorbent was performed for the fundamental understanding of zeolite topology and adsorption behaviour. The breakthrough experiments are used to evaluate the adsorption capacities on CO2/CH4 (40/60 vol%) binary biogas stream. The results were compared with commercial Na-LSX (C-Na-LSX). The breakthrough adsorption capacity of B-Na-LSX was 3.08 mmol g(-1) and 0.29 mmol g(-1) of CO2 and CH4, respectively, at 300 K and 1 bar. CO2 sorption capacity of B-Na-LSX was similar to 11 % and similar to 17 % higher than B-NaK-LSX (2.77 mmol g(-1)) and C-Na-LSX (2.56 mmol g(-1)), respectively. DFT study reveals that the higher adsorption of CO2 over CH4 was attributed to higher charge transfer from CO2 to zeolite framework. Dual-bed six-step Pressure Swing Adsorption (PSA) was performed on B-Na-LSX at 6 bar. similar to 232 cycles were run with above 98 % of CH4 purity and similar to 74 % of recovery. The life-cycle test of sorbent was studied. It was implied that the designed sorbent is effective to produce the high purity of CH4 and can be utilized for a longer period for CH4 production.

10aBinderless10aBiogas10aLSX zeolite10amethane10aPSA10aSeparation1 aYadav, Tushar, R.1 aShrotri, Aadesh, R.1 aKate, Pranjali, N.1 aDevasia, George1 aNiphadkar, Prashant, S.1 aMali, Nilesh, A.1 aKrishnamurty, Sailaja1 aBokade, Vijay, V.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/binderless-low-silica-x-zeolite-methane-separation-binary-co2ch4-biogas-stream-comprehensive02284nas a2200229 4500008004100000022001400041245013800055210006900193260000800262300001200270490000800282520147000290653001401760653002201774653002301796653002201819653002201841653001601863100002401879700002601903856012501929 2025 eng d a0360-319900aOptimizing H2/CO2 binary gas mixture separation using Li-K-ETS-10 zeolite: Breakthrough analysis and impact of operational conditions0 aOptimizing H2CO2 binary gas mixture separation using LiKETS10 ze cMAR a673-6830 v1053 a

The polycation-exchanged ETS-10 (Li-K-ETS-10) zeolite was employed as a sorbent in breakthrough experiments using a binary H2/CO2 (75/25%) gas mixture. The data compared with parent adsorbent (NaK)-ETS-10, and mono cation exchange of ETS-10 (K-ETS-10 and Li-ETS-10). Adsorbents underwent for various characterization including XRD, Raman, FTIR, EDS, CO2-TPD, BET surface area, and pore diameter of samples to understand the physicochemical properties. CO2-TPD shows that Li-K-ETS-10 has higher basicity than parent (NaK)-ETS-10. The process parameters were optimized to ensure a higher CO2 sorption capacity and better H2 purity including effects of flow rate, pressure, temperature, feed concentration, bed height, and recyclability. The adsorption capacities of CO2 and H2 were found to be 1.57 mmol g- 1 and 0.24 mmol g-1, respectively, at 1 bar and a flow rate of 200 mL min- 1. These values represent a 40% improvement over (NaK)-ETS-10 and a-10.4% improvement over Li-ETS-10. At 6 bar, the CO2 and H2 adsorption capacities reached 2.79 mmol g- 1 and 0.22 mmol g-1, respectively. The higher CO2 sorption over Li-K-ETS-10 leads due to improve in basic sites and physical properties of sample compare to studied adsorbent. The experimental data of binary gas mixture was used to evaluate the kinetic models including Thomas, and Yoon-Nelson. This results implies that Li-K-ETS-10 is the promising candidates for H2 separation from binary gas mixture.

10aadsorbent10aBinary gas stream10aBreakthrough study10aH2/CO2 separation10aKinetic modelling10aLi-K-ETS-101 aShrotri, Aadesh, R.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/optimizing-h2co2-binary-gas-mixture-separation-using-li-k-ets-10-zeolite-breakthrough02525nas a2200241 4500008004100000022001400041245010900055210006900164260000900233300001100242490000800253520173500261653001501996653002502011653002402036653001002060653001302070653000802083100002002091700002402111700002602135856012202161 2026 eng d a1387-181100aSynthesis of Core-Shell ETS-4@LSX zeolite composite to enhance CO2/N2 selectivity in flue gas separation0 aSynthesis of CoreShell ETS4LSX zeolite composite to enhance CO2N cJAN  a1138400 v3993 a

The selective removal of CO2 from the flue gas remains a quite challenging due to the weak selectivity of CO2/N2 in adsorbents. Therefore, it is necessary to design an effective sorbent to improve its selectivity. This work attempts to synthesis of novel core-shell ETS-4@LSX composite via a seed-assisted hydrothermal method. In this composite structure, a small pore titanosilcate ETS-4 as a core, while a large pore aluminosilicate LSX forms the outer shell. The effects of ETS-4 seed loading (1-5 wt.%) and crystallization time on the formation and structural integrity of the core-shell architecture was systematically investigated. The structural and physicochemical properties of samples were characterized by XRD, FE-SEM, HR-TEM, EDS, FT-IR, TGA, N2 adsorption-desorption, and pore size distribution. From XRD pattern and FE-SEM results confirmed that the composite synthesized with 2 wt% ETS-4 seed and 3 h crystallization time has pure phase of ETS-4@LSX structure. HR-TEM imaging revealed uniform growth of LSX over the ETS-4 surface, resulting in the formation of a continuous shell. The 2 wt% ETS4@LSX composite demonstrated an outstanding CO2/N2 equilibrium selectivity of 81.4 at 1 bar and 303 K with five and seven times higher than that of pure LSX and ETS-4, respectively. At 20 bar, the composite achieved a CO2 uptake of 5.25 mmol g- 1 and an N2 uptake of 0.50 mmol g- 1. Dynamic adsorption study exhibited the 2 wt% ETS-4@LSX has 3.52 mmol g- 1 CO2 sorption capacity and N2 uptake capacity of 0.26 mmol g- 1. The enhanced adsorption capacity and selectivity of ETS-4@LSX are attributed to its dual-pore structure, highlighting its potential as an effective adsorbent for CO2 capture from flue gas.

10aAdsorption10aCore-shell composite10aDual-pore structure10aETS-410aFlue gas10aLSX1 aBirje, Amit, R.1 aShrotri, Aadesh, R.1 aNandanwar, Sachin, U. uhttps://library.ncl.res.in/content/synthesis-core-shell-ets-4lsx-zeolite-composite-enhance-co2n2-selectivity-flue-gas