Novel activated carbon-zeolite composite adsorbent was prepared from macadamia shell bio-waste and synthetic zeolite X using hydrothermal treatment.Characterisation studies revealed mainly mesoporous structure with 41...Novel activated carbon-zeolite composite adsorbent was prepared from macadamia shell bio-waste and synthetic zeolite X using hydrothermal treatment.Characterisation studies revealed mainly mesoporous structure with 418 m^2·g^(-1) BET surface area with faujasite clusters on the carbon carrier.Sorption capacity for methylene blue model pollutant increased from 85 to 97 mg·g^(-1) with the temperature increase from 25 to 45 ℃, and improved with increasing pH.Nonlinear regression analyses found accurate fit to the pseudo-first-order kinetics model and intra-particle diffusion rate controlling mechanism.Excellent fits to the Jovanovic isotherm model indicated monolayer coverage on chiefly homotattic surfaces with variable potential.The thermodynamic analysis confirmed spontaneous and endothermic physisorption process.The spent adsorbent was regenerated with 20% capacity loss over five reuse cycles.Although the adsorbent was developed for ammonia, heavy metal and organic matter removal from water sources, the results also indicate good performance in cationic dye removal from wastewaters.展开更多
Zwitterionic glycine was employed to modify Fe/Mg-layered double hydroxides(LDH)to realize an GFe/Mg-LDH adsorbent with high adsorption capacities of oxygen-containing anions including As(Ⅴ),P(Ⅴ)and Cr(Ⅵ).When the ...Zwitterionic glycine was employed to modify Fe/Mg-layered double hydroxides(LDH)to realize an GFe/Mg-LDH adsorbent with high adsorption capacities of oxygen-containing anions including As(Ⅴ),P(Ⅴ)and Cr(Ⅵ).When the Fe/Mg mole ratio was 0.02 mol/0.02 mol,the G-Fe/Mg-LDH has a good adsorption performance.The optimum adsorption pH value of G-Fe/Mg-LDH for oxygen-containing anions was 6.The selectivity of three oxygen-containing anions was Cr(Ⅵ)展开更多
Efficient adsorption of gaseous radioiodine is pivotal for the sustainable development of nuclear energy and the long-termradiation safety of the ecological system.However,state-of-the-art adsorbents(e.g.metal-organic...Efficient adsorption of gaseous radioiodine is pivotal for the sustainable development of nuclear energy and the long-termradiation safety of the ecological system.However,state-of-the-art adsorbents(e.g.metal-organic frameworks and covalent-organic frameworks)currently under exploration suffer severely from limited adsorption capacity,especially under a real-world scenariowith extremely lowradioiodine concentration and elevated temperature.This mostly originates from the relatively weak sorption driving forces mainly determinedby the iodine-adsorbent interaction consistingof noncovalent interactionswith a small fraction of strong chemical bonding.Here,we document the discovery of an open metal-sulfide framework((NH_(4))_(2)(Sn_(3)S_(7)),donated as SCU-SnS)constructed by three different types of active sites as a superior iodine adsorbent.Benefiting from the ability of iodine for pre-enrichment into the framework by charge-balancing NH_(4)^(+)through N-H···I interaction,the efficient reduction of I^(2)affording I^(-)by S^(2-),and extremely high binding affinity between Sn_(4)^(+)and I^(-),SCU-SnS exhibit a record-breaking iodine adsorption capacity(2.12 g/g)under dynamic breakthrough conditions and the highest static capacity(6.12 g/g)among all reported inorganic adsorbents,both at 348 K.Its facile synthesis and low cost endow SCU-SnS with powerful application potential for the nuclear industry.展开更多
基金the University of Southern Queensland and Australian Government Research Training Program Scholarship for providing a scholarship to pursue this work
文摘Novel activated carbon-zeolite composite adsorbent was prepared from macadamia shell bio-waste and synthetic zeolite X using hydrothermal treatment.Characterisation studies revealed mainly mesoporous structure with 418 m^2·g^(-1) BET surface area with faujasite clusters on the carbon carrier.Sorption capacity for methylene blue model pollutant increased from 85 to 97 mg·g^(-1) with the temperature increase from 25 to 45 ℃, and improved with increasing pH.Nonlinear regression analyses found accurate fit to the pseudo-first-order kinetics model and intra-particle diffusion rate controlling mechanism.Excellent fits to the Jovanovic isotherm model indicated monolayer coverage on chiefly homotattic surfaces with variable potential.The thermodynamic analysis confirmed spontaneous and endothermic physisorption process.The spent adsorbent was regenerated with 20% capacity loss over five reuse cycles.Although the adsorbent was developed for ammonia, heavy metal and organic matter removal from water sources, the results also indicate good performance in cationic dye removal from wastewaters.
文摘Zwitterionic glycine was employed to modify Fe/Mg-layered double hydroxides(LDH)to realize an GFe/Mg-LDH adsorbent with high adsorption capacities of oxygen-containing anions including As(Ⅴ),P(Ⅴ)and Cr(Ⅵ).When the Fe/Mg mole ratio was 0.02 mol/0.02 mol,the G-Fe/Mg-LDH has a good adsorption performance.The optimum adsorption pH value of G-Fe/Mg-LDH for oxygen-containing anions was 6.The selectivity of three oxygen-containing anions was Cr(Ⅵ)
基金The authors gratefully acknowledge the financial support from the National Key R&D Program of China(grant nos.2021YFB3200400 and 2018YFB1900203)the National Natural Science Foundation of China(grant nos.21825601,21790374,22176139,21906113,and 22176163)+2 种基金the Young Taishan Scholars Program(grant no.tsqn201909082)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(grant no.KYCX22_3212)This work is dedicated to Prof.Zhifang Chai on the occasion of his 80th birthday.
文摘Efficient adsorption of gaseous radioiodine is pivotal for the sustainable development of nuclear energy and the long-termradiation safety of the ecological system.However,state-of-the-art adsorbents(e.g.metal-organic frameworks and covalent-organic frameworks)currently under exploration suffer severely from limited adsorption capacity,especially under a real-world scenariowith extremely lowradioiodine concentration and elevated temperature.This mostly originates from the relatively weak sorption driving forces mainly determinedby the iodine-adsorbent interaction consistingof noncovalent interactionswith a small fraction of strong chemical bonding.Here,we document the discovery of an open metal-sulfide framework((NH_(4))_(2)(Sn_(3)S_(7)),donated as SCU-SnS)constructed by three different types of active sites as a superior iodine adsorbent.Benefiting from the ability of iodine for pre-enrichment into the framework by charge-balancing NH_(4)^(+)through N-H···I interaction,the efficient reduction of I^(2)affording I^(-)by S^(2-),and extremely high binding affinity between Sn_(4)^(+)and I^(-),SCU-SnS exhibit a record-breaking iodine adsorption capacity(2.12 g/g)under dynamic breakthrough conditions and the highest static capacity(6.12 g/g)among all reported inorganic adsorbents,both at 348 K.Its facile synthesis and low cost endow SCU-SnS with powerful application potential for the nuclear industry.
