Superior adsorption performance of graphitic carbon nitride nanosheets for both cationic and anionic heavy metals from wastewater
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摘要
Water pollution caused by highly toxic Cd(II), Pb(II), and Cr(VI) is a serious problem. In the present work,a green and low-cost adsorbent of g-C_3N_4 nanosheets was developed with superior capacity for both cationic and anionic heavy metals. The adsorbent was easily fabricated through one-step calcination of guanidine hydrochloride with thickness less than 1.6 nm and specific surface area of 111.2 m~2·g~(-1). Kinetic and isotherm studies suggest that the adsorption is an endothermic chemisorption process, occurring on the energetically heterogeneous surface based on a hybrid mechanism of multilayer and monolayer adsorption. The tri-s-triazine units and surface N-containing groups of g-C_3N_4 nanosheets are proposed to be responsible for the adsorption process.Further study on pH demonstrates that electrostatic interaction plays an important role. The maximum adsorption capacity of Cd(II), Pb(II), and Cr(VI) on g-C_3N_4 nanosheets is 123.205 mg·g~(-1), 136.571 mg·g~(-1),and 684.451 mg·g~(-1), respectively. The better adsorption performance of the adsorbent than that of the recently reported nanomaterials and low-cost adsorbents proves its great application potential in the removal of heavy metal contaminants from wastewater. The present paper developed a promising adsorbent which will certainly find applications in wastewater treatment and also provides guiding significance in designing adsorption processes.
Water pollution caused by highly toxic Cd(II), Pb(II), and Cr(VI) is a serious problem. In the present work,a green and low-cost adsorbent of g-C_3N_4 nanosheets was developed with superior capacity for both cationic and anionic heavy metals. The adsorbent was easily fabricated through one-step calcination of guanidine hydrochloride with thickness less than 1.6 nm and specific surface area of 111.2 m~2·g~(-1). Kinetic and isotherm studies suggest that the adsorption is an endothermic chemisorption process, occurring on the energetically heterogeneous surface based on a hybrid mechanism of multilayer and monolayer adsorption. The tri-s-triazine units and surface N-containing groups of g-C_3N_4 nanosheets are proposed to be responsible for the adsorption process.Further study on pH demonstrates that electrostatic interaction plays an important role. The maximum adsorption capacity of Cd(II), Pb(II), and Cr(VI) on g-C_3N_4 nanosheets is 123.205 mg·g~(-1), 136.571 mg·g~(-1),and 684.451 mg·g~(-1), respectively. The better adsorption performance of the adsorbent than that of the recently reported nanomaterials and low-cost adsorbents proves its great application potential in the removal of heavy metal contaminants from wastewater. The present paper developed a promising adsorbent which will certainly find applications in wastewater treatment and also provides guiding significance in designing adsorption processes.
Water pollution caused by highly toxic Cd(II), Pb(II), and Cr(VI) is a serious problem. In the present work,a green and low-cost adsorbent of g-C_3N_4 nanosheets was developed with superior capacity for both cationic and anionic heavy metals. The adsorbent was easily fabricated through one-step calcination of guanidine hydrochloride with thickness less than 1.6 nm and specific surface area of 111.2 m~2·g~(-1). Kinetic and isotherm studies suggest that the adsorption is an endothermic chemisorption process, occurring on the energetically heterogeneous surface based on a hybrid mechanism of multilayer and monolayer adsorption. The tri-s-triazine units and surface N-containing groups of g-C_3N_4 nanosheets are proposed to be responsible for the adsorption process.Further study on pH demonstrates that electrostatic interaction plays an important role. The maximum adsorption capacity of Cd(II), Pb(II), and Cr(VI) on g-C_3N_4 nanosheets is 123.205 mg·g~(-1), 136.571 mg·g~(-1),and 684.451 mg·g~(-1), respectively. The better adsorption performance of the adsorbent than that of the recently reported nanomaterials and low-cost adsorbents proves its great application potential in the removal of heavy metal contaminants from wastewater. The present paper developed a promising adsorbent which will certainly find applications in wastewater treatment and also provides guiding significance in designing adsorption processes.
引文
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[28]L.Vafajoo,R.Cheraghi,R.Dabbagh,G.McKay,Removal of cobalt(II)ions from aqueous solutions utilizing the pre-treated 2-Hypnea Valentiae algae:Equilibrium,thermodynamic,and dynamic studies,Chem.Eng.J.331(2018)39-47.
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[31]S.Yang,Y.Gong,J.Zhang,L.Zhan,L.Ma,Z.Fang,R.Vajtai,X.Wang,P.M.Ajayan,Exfoliated graphitic carbon nitride nanosheets as efficient catalysts for hydrogen evolution under visible light,Adv.Mater.25(2013)2452-2456.
[32]A.Kumar,P.Kumar,C.Joshi,M.Manchanda,R.Boukherroub,S.L.Jain,Nickel decorated on phosphorous-doped carbon nitride as an efficient photocatalyst for reduction of nitrobenzenes,Nanomaterials 6(2016)59.
[33]Y.Yu,Q.Zhou,J.Wang,The ultra-rapid synthesis of 2D graphitic carbon nitride nanosheets via direct microwave heating for field emission,Chem.Commun.52(2016)3396-3399.
[34]T.Phatthanakittiphong,G.T.Seo,Characteristic evaluation of graphene oxide for bisphenol A adsorption in aqueous solution,Nanomaterials 6(2016)128.
[35]M.Shaban,M.R.Abukhadra,Geochemical evaluation and environmental application of Yemeni natural zeolite as sorbent for Cd2+from solution:Kinetic modeling,equilibrium studies,and statistical optimization,Environ.Earth Sci.76(2017)310.
[36]M.Shaban,H.Mem,F.M.Nasief,M.R.Abukhadra,Adsorption properties of kaolinitebased nanocomposites for Fe and Mn pollutants from aqueous solutions and raw ground water:Kinetics and equilibrium studies,Environ.Sci.Pollut.Res.24(2017)22954-22966.
[37]L.Jiang,Y.Li,Y.Shao,Y.Zhang,R.Han,S.Li,W.Wei,Enhanced removal of humic acid from aqueous solution by novel stabilized nano-amorphous calcium phosphate:Behaviors and mechanisms,Appl.Surf.Sci.427((2018)965-975.
[38]N.Liu,Y.Wu,H.Sha,Characterization of EDTA-cross-linkedβ-cyclodextrin grafted onto Fe-Al hydroxides as an efficient adsorbent for methylene blue,J.Colloid Interface Sci.516(2018)98-109.
[39]S.Hena,Removal of chromium hexavalent ion from aqueous solutions using biopolymer chitosan coated with poly 3-methyl thiophene polymer,J.Hazard.Mater.181(2010)474-479.
[40]A.J.K.Kupeta,E.B.Naidoo,A.E.Ofomaja,Kinetics and equilibrium study of 2-nitrophenol adsorption onto polyurethane cross-linked pine cone biomass,J.Clean.Prod.179(2018)191-209.
[41]O.Pezoti,A.L.Cazetta,K.C.Bedin,L.S.Souza,A.C.Martins,T.L.Silva,O.O.Santos Júnior,J.V.Visentainer,V.C.Almeida,NaOH-activated carbon of high surface area produced from guava seeds as a high-efficiency adsorbent for amoxicillin removal:Kinetic,isotherm and thermodynamic studies,Chem.Eng.J.288(2016)778-788.
[42]A.R.Khan,R.Ataullah,A.Al-Haddad,Equilibrium adsorption studies of some aromatic pollutants from dilute aqueous solutions on activated carbon at different temperatures,J.Colloid Interface Sci.194(1997)154-165.
[43]J.Lin,B.Su,M.Sun,B.Chen,Z.Chen,Biosynthesized iron oxide nanoparticles used for optimized removal of cadmium with response surface methodology,Sci.Total Environ.627(2018)314-321.
[44]J.Xiang,Q.Lin,S.Cheng,J.Guo,X.Yao,Q.Liu,J.Yin,D.Liu,Enhanced adsorption of Cd(II)from aqueous solution by a magnesium oxide-rice husk biochar composite,Environ.Sci.Pollut.Res.25(2018)14032-14042.
[45]J.Chen,X.Lu,Equilibrium and kinetics studies of Cd(II)sorption on zeolite NaX synthesized from coal gangue,J.Water Reuse Desal.8(2018)94-101.
[46]D.Zhang,C.Wang,Q.Bao,J.Zheng,D.Deng,Y.Duan,L.Shen,The physicochemical characterization,equilibrium,and kinetics of heavy metal ions adsorption from aqueous solution by arrowhead plant(Sagittaria trifolia L.)stalk,J.Food Biochem.42(2018),e12448.
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[2]L.Li,F.Zhu,Y.Lu,J.Guan,Synthesis,adsorption and selectivity of inverse emulsion Cd(II)imprinted polymers,Chin.J.Chem.Eng.26(3)(2017)494-500.
[3]G.Xiao,X.Zhang,H.Su,T.Tan,Plate column biosorption of Cu(II)on membranetype biosorbent(MBS)of Penicillium biomass:Optimization using statistical design methods,Bioresour.Technol.143(2013)490-498.
[4]G.Liu,P.Wang,Q.Liu,W.Han,Removal of Cd(II)by nanometer AlO(OH)loaded on fiberglass with activated carbon fiber felt as carrier,Chin.J.Chem.Eng.16(5)(2008)805-811.
[5]H.Liu,X.Lu,M.Li,L.Zhang,C.Pan,R.Zhang,J.Li,W.Xiang,Structural incorporation of manganese into goethite and its enhancement of Pb(II)adsorption,Environ.Sci.Technol.52(8)(2018)4719-4727.
[6]Q.Liang,H.Luo,J.Geng,J.Chen,Facile one-pot preparation of nitrogen-doped ultralight graphene oxide aerogel and its prominent adsorption performance of Cr(VI),Chem.Eng.J.338(2017)62-71.
[7]F.Fu,Q.Wang,Removal of heavy metal ions from wastewaters:A review,J.Environ.Manag.92(2011)407-418.
[8]Y.Han,Z.Xu,C.Gao,Ultrathin graphene nanofiltration membrane for water purification,Adv.Funct.Mater.23(2013)3693-3700.
[9]S.Rengaraj,K.H.Yeon,S.H.Moon,Removal of chromium from water and wastewater by ion exchange resins,J.Hazard.Mater.87(2001)273-287.
[10]Y.Yang,Y.Xie,L.Pang,M.Li,X.Song,J.Wen,H.Zhao,Preparation of reduced graphene oxide/poly(acrylamide)nanocomposite and its adsorption of Pb(II)and methylene blue,Langmuir 29(2013)10727-10736.
[11]C.G.Lee,M.K.Song,J.C.Ryu,C.Park,J.W.Choi,S.H.Lee,Application of carbon foam for heavy metal removal from industrial plating wastewater and toxicity evaluation of the adsorbent,Chemosphere 153(2016)1-9.
[12]M.H.Mahaninia,P.Rahimian,T.Kaghazchi,Modified activated carbons with amino groups and their copper adsorption properties in aqueous solution,Chin.J.Chem.Eng.23(1)(2015)50-56.
[13]Y.El Mouzdahir,A.Elmchaouri,R.Mahboub,A.ElAnssari,A.Gil,S.A.Korili,M.A.Vicente,Interaction of stevensite with Cd2+and Pb2+in aqueous dispersions,Appl.Clay Sci.35(2007)47-58.
[14]G.Xiao,K.Lan,H.Su,T.Tan,Preparation of a modified chitosan-mycelium adsorbent with polyvinyl alcohol,Sep.Sci.Technol.49(2014)1279-1288.
[15]M.A.Habila,Z.A.ALOthman,A.M.El-Toni,J.P.Labis,A.Khan,A.Al-Marghany,H.E.Elafifi,One-step carbon coating and polyacrylamide functionalization of Fe3O4nanoparticles for enhancing magnetic adsorptive-remediation of heavy metals,Molecules 22(2017)2074.
[16]J.Xu,Z.Cao,Y.Zhang,Z.Yuan,Z.Lou,X.Xu,X.Wang,A review of functionalized carbon nanotubes and graphene for heavy metal adsorption from water:Preparation,application,and mechanism,Chemosphere 195(2018)351-364.
[17]E.Salehi,L.Bakhtiari,M.Askari,Extended adsorption transport models for permeation of copper ions through nanocomposite chitosan/polyvinyl alcohol thin affinity membranes,Chin.J.Chem.Eng.24(11)(2016)1527-1532.
[18]G.Vilardi,T.Mpouras,D.Dermatas,N.Verdone,A.Polydera,L.Di Palma,Nanomaterials application for heavy metals recovery from polluted water:The combination of nano zero-valent iron and carbon nanotubes.Competitive adsorption non-linear modeling,Chemosphere 201(2018)716-729.
[19]C.Shen,C.Chen,T.Wen,Z.Zhao,X.Wang,A.Xu,Superior adsorption capacity of g-C3N4for heavy metal ions from aqueous solutions,J.Colloid Interface Sci.456(2015)7-14.
[20]Y.Zheng,L.Lin,B.Wang,X.Wang,Graphitic carbon nitride polymers toward sustainable photoredox catalysis,Angew.Chem.Int.Ed.54(2015)12868-12884.
[21]A.Thomas,A.Fischer,F.Goettmann,M.Antonietti,J.O.Müller,R.Schl?gl,J.M.Carlsson,Graphitic carbon nitride materials:Variation of structure and morphology and their use as metal-free catalysts,J.Mater.Chem.18(2008)4893-4908.
[22]S.Cao,J.Low,J.Yu,M.Jaroniec,Polymeric photocatalysts based on graphitic carbon nitride,Adv.Mater.27(2015)2150-2176.
[23]X.Cai,J.He,L.Chen,K.Chen,Y.Li,K.Zhang,Z.Jin,J.Liu,C.Wang,X.Wang,L.Kong,J.Liu,A 2D-g-C3N4nanosheet as an eco-friendly adsorbent for various environmental pollutants in water,Chemosphere 171(2017)192-201.
[24]Z.Chen,S.Mitchell,E.Vorobyeva,R.K.Leary,R.Hauert,T.Furnival,Q.M.Ramasse,J.M.Thomas,P.A.Midgley,D.Dontsova,M.Antonietti,S.Pogodin,N.López,J.Pérez-Ramírez,Stabilization of single metal atoms on graphitic carbon nitride,Adv.Funct.Mater.27(2017)1605785.
[25]C.Daikopoulos,Y.Georgiou,A.B.Bourlinos,M.Baikousi,M.A.Karakassides,R.Zboril,T.A.Steriotis,Y.Deligiannakis,Arsenite remediation by an amine-rich graphitic carbon nitride synthesized by a novel low-temperature method,Chem.Eng.J.256(2014)347-355.
[26]Z.Huang,F.Li,B.Chen,G.Yuan,Nanosheets of graphitic carbon nitride as metal-free environmental photocatalysts,Catal.Sci.Technol.4(2014)4258-4264.
[27]E.S.Dragan,D.Humelnicu,M.V.Dinu,R.I.Olariu,Kinetics,equilibrium modeling,and thermodynamics on removal of Cr(VI)ions from aqueous solution using novel composites with strong base anion exchanger microspheres embedded into chitosan/poly(vinyl amine)cryogels,Chem.Eng.J.330(2017)675-691.
[28]L.Vafajoo,R.Cheraghi,R.Dabbagh,G.McKay,Removal of cobalt(II)ions from aqueous solutions utilizing the pre-treated 2-Hypnea Valentiae algae:Equilibrium,thermodynamic,and dynamic studies,Chem.Eng.J.331(2018)39-47.
[29]A.Günay,E.Arslankaya,I.Tosun,Lead removal from aqueous solution by natural and pretreated clinoptilolite:Adsorption equilibrium and kinetics,J.Hazard.Mater.146(2007)362-371.
[30]P.Yang,H.Ou,Y.Fang,X.Wang,A facile steam reforming strategy to delaminate layered carbon nitride semiconductors for photoredox catalysis,Angew.Chem.Int.Ed.56(2017)3992-3996.
[31]S.Yang,Y.Gong,J.Zhang,L.Zhan,L.Ma,Z.Fang,R.Vajtai,X.Wang,P.M.Ajayan,Exfoliated graphitic carbon nitride nanosheets as efficient catalysts for hydrogen evolution under visible light,Adv.Mater.25(2013)2452-2456.
[32]A.Kumar,P.Kumar,C.Joshi,M.Manchanda,R.Boukherroub,S.L.Jain,Nickel decorated on phosphorous-doped carbon nitride as an efficient photocatalyst for reduction of nitrobenzenes,Nanomaterials 6(2016)59.
[33]Y.Yu,Q.Zhou,J.Wang,The ultra-rapid synthesis of 2D graphitic carbon nitride nanosheets via direct microwave heating for field emission,Chem.Commun.52(2016)3396-3399.
[34]T.Phatthanakittiphong,G.T.Seo,Characteristic evaluation of graphene oxide for bisphenol A adsorption in aqueous solution,Nanomaterials 6(2016)128.
[35]M.Shaban,M.R.Abukhadra,Geochemical evaluation and environmental application of Yemeni natural zeolite as sorbent for Cd2+from solution:Kinetic modeling,equilibrium studies,and statistical optimization,Environ.Earth Sci.76(2017)310.
[36]M.Shaban,H.Mem,F.M.Nasief,M.R.Abukhadra,Adsorption properties of kaolinitebased nanocomposites for Fe and Mn pollutants from aqueous solutions and raw ground water:Kinetics and equilibrium studies,Environ.Sci.Pollut.Res.24(2017)22954-22966.
[37]L.Jiang,Y.Li,Y.Shao,Y.Zhang,R.Han,S.Li,W.Wei,Enhanced removal of humic acid from aqueous solution by novel stabilized nano-amorphous calcium phosphate:Behaviors and mechanisms,Appl.Surf.Sci.427((2018)965-975.
[38]N.Liu,Y.Wu,H.Sha,Characterization of EDTA-cross-linkedβ-cyclodextrin grafted onto Fe-Al hydroxides as an efficient adsorbent for methylene blue,J.Colloid Interface Sci.516(2018)98-109.
[39]S.Hena,Removal of chromium hexavalent ion from aqueous solutions using biopolymer chitosan coated with poly 3-methyl thiophene polymer,J.Hazard.Mater.181(2010)474-479.
[40]A.J.K.Kupeta,E.B.Naidoo,A.E.Ofomaja,Kinetics and equilibrium study of 2-nitrophenol adsorption onto polyurethane cross-linked pine cone biomass,J.Clean.Prod.179(2018)191-209.
[41]O.Pezoti,A.L.Cazetta,K.C.Bedin,L.S.Souza,A.C.Martins,T.L.Silva,O.O.Santos Júnior,J.V.Visentainer,V.C.Almeida,NaOH-activated carbon of high surface area produced from guava seeds as a high-efficiency adsorbent for amoxicillin removal:Kinetic,isotherm and thermodynamic studies,Chem.Eng.J.288(2016)778-788.
[42]A.R.Khan,R.Ataullah,A.Al-Haddad,Equilibrium adsorption studies of some aromatic pollutants from dilute aqueous solutions on activated carbon at different temperatures,J.Colloid Interface Sci.194(1997)154-165.
[43]J.Lin,B.Su,M.Sun,B.Chen,Z.Chen,Biosynthesized iron oxide nanoparticles used for optimized removal of cadmium with response surface methodology,Sci.Total Environ.627(2018)314-321.
[44]J.Xiang,Q.Lin,S.Cheng,J.Guo,X.Yao,Q.Liu,J.Yin,D.Liu,Enhanced adsorption of Cd(II)from aqueous solution by a magnesium oxide-rice husk biochar composite,Environ.Sci.Pollut.Res.25(2018)14032-14042.
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