@article { ISI:000358610200004, title = {Fruit peel waste as a novel low-cost bio adsorbent}, journal = {Reviews in Chemical Engineering}, volume = {31}, number = {4}, year = {2015}, month = {AUG}, pages = {361-381}, publisher = {WALTER DE GRUYTER GMBH}, address = {GENTHINER STRASSE 13, D-10785 BERLIN, GERMANY}, abstract = {

Fruit peel waste (FPW) is abundantly available from the agricultural and food processing industry and has been studied in recent past as an adsorbent. This paper critically reviews the reported work and investigates various FPW-pollutant systems. The study includes statistics of FPW generation, modification, characterization, adsorption ability, recovery/regeneration, and modeling (isotherms, kinetics, and thermodynamics) of batch adsorption. It is found that orange and banana peels are the most extensively studied adsorbents, whereas Pb2+ and methylene blue are the most efficiently removed pollutants, the Langmuir and Freundlich adsorption isotherms provide the best fit in most of the cases, and in general, pseudo-second-order kinetics is followed. There are very limited column studies and no report on commercial plant. Though the reproducibility of the results is poor, FPW has a great potential in the wastewater treatment due to its abundant and cheap availability. FPW can be used for removal of heavy metals and dyes; however, removal of organic and gaseous impurities needs further investigation.

}, keywords = {adsorbent, Adsorption, fruit peel waste, organic and inorganic pollutants, wastewater}, issn = {0167-8299}, doi = {10.1515/revce-2014-0041}, author = {Pathak, Pranav D. and Mandavgane, Sachin A. and Kulkarni, Bhaskar D.} } @article {47639, title = {Fabrication of bacterial nanocellulose/polyethyleneimine (PEI-BC) based cationic adsorbent for efficient removal of anionic dyes}, journal = {Journal of Polymer Research}, volume = {28}, year = {2021}, month = {SEP}, pages = {354}, type = {Article}, abstract = {A bacterial cellulose (BC) based adsorbent was prepared by using polyethyleneimine (PEI) using epichlorohydrin as a cross-linker. The physicochemical characterization of the of the developed adsorbent was carried out using FTIR, BET analysis and SEM, respectively. The dye removal efficiency of the adsorbent was assessed towards two anionic model dyes viz. congo red (CR) and reactive red 120(RR). The kinetic data for the removal of both the anionic dyes were fitted better using pseudo-second-order model. Langmuir model describes well the process of adsorption with predicted maximum adsorption capacity (q(max)) 515.46 and 300.3 mg L-1 for CR (at pH 6.0) and RR (at pH 3.0) respectively. The adsorption-desorption study showed that PEI-BC adsorbent is effective with more than 90\% dye removal efficiency even after four cycles. Furthermore, the bactericidal activity of the adsorbent was analysed using Escherichia coli and Staphylococcus aureus and adsorbent showed good inhibition against both test organisms. The study reveals that PEI-BC adsorbent can be a good candidate for water remediation purpose bearing multifunctional behaviour.}, keywords = {adsorbent, Anionic dyes, Bacterial cellulose, Bactericidal, Polyethyleneimine}, issn = {1022-9760}, doi = {10.1007/s10965-021-02702-y}, author = {Thorat, Meghana N. and Jagtap, Ashish and Dastager, Syed G.} } @article {48291, title = {Short review on recent advances in porous adsorbents for separation of oxygen from atmospheric air}, journal = {Asia-Pacific Journal of Chemical Engineering}, volume = {18}, year = {2023}, month = {MAR}, type = {Review}, abstract = {

Pure 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 O-2 from atmospheric air. The porous solid adsorbent is a key element in the PSA to trap nitrogen (N-2) and release O-2. 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 N-2 from the air. This review article is a summarization of recent research work published on O-2 separation using different porous adsorbents via PSA. This review also emphasizes on the best porous sorbent for purification of O-2 by sorption of N-2 and Ar. The adsorption capacities with experimental conditions are also rigorously discussed. The review also proposed future trends and prospects for O-2 separation. This review will be helpful to choose remarkable adsorbent for the generation pure O-2.

}, keywords = {13X zeolite, adsorbent, ETS-10, oxygen, Separation}, issn = {1932-2135}, doi = {10.1002/apj.2896}, author = {Shrotri, Aadesh R. R. and Niphadkar, Prashant S. S. and Bokade, Vijay V. V. and Utgikar, Vivek P. P. and Nandanwar, Sachin U. U.} } @article {49254, title = {Pressure swing adsorption of Li exchange hierarchical X zeolite for pure hydrogen from binary gas mixture}, journal = {International Journal of Hydrogen Energy}, volume = {73}, year = {2024}, month = {JUL }, pages = {138-147}, type = {Article}, abstract = {

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.

}, keywords = {adsorbent, Binary gas mixture, Hydrogen purification, Li-H-X, Mesoporous zeolite, Pressure swing adsorption}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2024.06.011}, author = {Shrotri, Aadesh R. and Birje, Amit R. and Nandanwar, Sachin U.} } @article {49529, title = {Optimizing H2/CO2 binary gas mixture separation using Li-K-ETS-10 zeolite: Breakthrough analysis and impact of operational conditions}, journal = {International Journal of Hydrogen Energy}, volume = {105}, year = {2025}, month = {MAR}, pages = {673-683}, type = {Article}, abstract = {

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.

}, keywords = {adsorbent, Binary gas stream, Breakthrough study, H2/CO2 separation, Kinetic modelling, Li-K-ETS-10}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2025.01.324}, author = {Shrotri, Aadesh R. and Nandanwar, Sachin U.} }