The presence of Hg in the aqueous media is known to cause severe health issues in both humans and animals.Many technologies and especially adsorbents have been applied for its removal. In this study, a graphene oxide...The presence of Hg in the aqueous media is known to cause severe health issues in both humans and animals.Many technologies and especially adsorbents have been applied for its removal. In this study, a graphene oxide–carbon composite(GO–CC) as a new adsorbent was prepared by sol gel procedure and characterized using field emission scanning electron microscopy, BET and EDX. The effects of different variables including solution p H, contact time, adsorbent dose and GO ratio in adsorbent matrix on the removal capacity of Hg were studied. The isotherm data correlated well with the Langmuir isotherm model. Further analysis recommended that the Hg^(2+) adsorption process is governed by the intra-particle and external mass transfer, in which the film diffusion was the rate restrictive step. The presented composite has maximum absorption capacity, q_(max) of 68.8 mg·g^(-1), which is comparable with carbon based adsorbent reported in the previous publications.展开更多
A new composite adsorbent, nano-Fe3O4/bacterial cellulose（BC）, was prepared through blending method. The process of adsorbing Cd2＋ including its isotherm and kinetics measured was studied. The results show that the...A new composite adsorbent, nano-Fe3O4/bacterial cellulose（BC）, was prepared through blending method. The process of adsorbing Cd2＋ including its isotherm and kinetics measured was studied. The results show that the adsorption efficiency is improved because of huge surface area and surface coordination of nano-Fe3O4 particles. Its adsorption capacity is 27.97 mg/g and the maximum of Cd2＋ removal is 74%. The adsorption kinetics can be described by pseudo-second rate model and the adsorption equilibrium by Langmuir type. The superparamagnetism of nano-Fe3O4 particles can help to solve the difficult separation of single BC adsorbent and lead to the quick separation of composite adsorbent from the liquid if a magnetic field was applied. Cd2＋ can be desorbed effectively by EDTA and HCl from the composite adsorbent, which can make it be reused.展开更多
Thermal conductivity is one of key parameters of adsorbents, which will affect the overall system performance of adsorption chiller. To improve adsorbent＇s thermal conductivity is always one of research focuses in ch...Thermal conductivity is one of key parameters of adsorbents, which will affect the overall system performance of adsorption chiller. To improve adsorbent＇s thermal conductivity is always one of research focuses in chemisorption field. A new chemical composite adsorbent is fabricated by adding carbon coated metal（Aluminum and Nickel） nanoparticles with three different addition amounts into the mixture of chloride salts and natural expanded graphite aiming to improve the thermal conductivity. The preparation processes and its thermal conductivity of this novel composite adsorbent are reported and summarized. Experimental results indicate that the nanoparticles are homogenously dispersed in the composite adsorbent by applying the reported preparation processes. The thermal conductivity of the composite adsorbent can averagely enlarge by 20% when the weight ratio of the added nanoparticles is 10 wt%. Moreover, carbon coated aluminum nanoparticles exhibit more effective enlargement in thermal conductivity than nickel nanoparticles. As for the composite adsorbent of CaCl2-NEG, there is a big reinforcement from 30% to 50% for Al@C nanoparticles, however only 10% in maximum caused by Ni@C nanoparticles. The proposed research provides a methodology to design and prepare thermal conductive chemical composite adsorbent.展开更多
This work reports the adsorption of strontium from aqueous solutions onto PAN/zeolite composite. The strontium adsorption on the composite adsorbent was studied as a function of initial strontium concentration, pH of ...This work reports the adsorption of strontium from aqueous solutions onto PAN/zeolite composite. The strontium adsorption on the composite adsorbent was studied as a function of initial strontium concentration, pH of the solution, contact time and temperature. Adsorption isotherms like Langmuir, Freundlich,Dubinin–Radushkevich (D–R) and Temkin were used to analyze the equilibrium data at the different concentrations.Adsorption process well fitted to Temkin isotherm model. Thermodynamic parameters such as the changes in enthalpy, entropy and Gibbs’ free energy were determined, showing adsorption to be an exothermic and spontaneous process.展开更多
As a kind of rare metals,rubidium is often used to prepare special glass,photomultiplier tubes,thermoelectric converter,organic catalysts and antidepressants.Rubidium forms no minerals of its own,hence,it often coexis...As a kind of rare metals,rubidium is often used to prepare special glass,photomultiplier tubes,thermoelectric converter,organic catalysts and antidepressants.Rubidium forms no minerals of its own,hence,it often coexists with展开更多
The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal fu...The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal function.Herein,we proposed a novel strategy of thin-film nanofibrous composite(TNFC)dialysis membrane combined with reduced graphene oxide(rGO)aerogel adsorbents for clinical removal of IS as well as high retention of proteins.The TFNC membrane was prepared by electrospinning in conjunction with coating-reaction method and proved to have good selectivity and permeability.To further improve the removal rate of toxins,we used a medium hydrothermal method following by freeze-drying treatment to obtain the r GO aerogel adsorbents.It exhibited excellent adsorption for IS with a maximum adsorption capacity of 69.40 mg·g^(-1)throughπ-πinteraction and hydrogen bonding interaction based on Langmuir isotherm models.Time-dependent absorption experiments showed that it reached adsorption equilibrium within 4 h,which was matched with the hemodialysis time.The coordination was significantly exhibited by introducing r GO aerogel blocks into the dialysate for absorbing the diffused free IS during hemodialysis.Taking the advantages of the TFNC dialysis membrane and the rGO aerogel,the volume of dialysate for hemodialysis was only one-tenth of that without adsorbent blocks but with very comparable dialysis performance(the clearance of IS at 51.8%and the retention of HSA over 98%),which could lighten conventional hemodialysis effectively and be benefit to realize the miniaturization of the hemodialysis equipment.Therefore,the coordination of the TFNC dialysis membrane and rGO aerogel adsorbents would open a new path for the development of portable artificial kidney.展开更多
A novel carbon-sulfur nano-composite material was synthesized by heating sublimed sulfur and high surface area activated carbon （HSAAC） under certain conditions. The physical and chemical per- formances of the novel...A novel carbon-sulfur nano-composite material was synthesized by heating sublimed sulfur and high surface area activated carbon （HSAAC） under certain conditions. The physical and chemical per- formances of the novel carbon-sulfur nano-composite were characterized by scanning electron microscopy （SEM）, Brunauer-Emmett-Teller （BET） and X-ray diffraction （XRD）. The electrochemical performances of nano-composite were characterized by charge-discharge characteristic, cyclic voltammetry and electrochemical impendence spectroscopy （EIS）. The experimental results indicate that the electrochemical capability of nano- composite material was superior to that of traditional S-containing composite material. The cathode made by carbon-sulfur nano-composite material shows a good cycle ability and a high specific charge-discharge capacity. The HSAAC shows a vital role in adsorbing sublimed sulfur and the polysulfides within the cathode and is an excellent electric conductor for a sulfur cathode and prevents the shuttle behavior of the lithium-sulfur battery.展开更多
Lithium-sulfur(Li-S)battery is labeled as a promising high-energy-density battery system,but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical application...Lithium-sulfur(Li-S)battery is labeled as a promising high-energy-density battery system,but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical applications.Herein,an integrated approach is proposed to fabricate the high-performance rGO/VS_(4)/S cathode composites through a simple one-step solvothermal method,where nano sulfur and VS_(4) particles are uniformly distributed on the conductive rGO matrix.rGO and sulfiphilic VS_(4)provide electron transfer skeleton and physical/chemical anchor for soluble lithium polysulfides(LiPS).Meanwhile,VS_(4) could also act as an electrochemical mediator to efficiently enhance the utilization and reversible conversion of LiPS.Correspondingly,the rGO/VS_(4)/S composites maintain a high reversible capacity of 969 mAh/g at 0.2 C after 100 cycles,with a capacity retention rate of 82.3%.The capacity fade rate could lower to 0.0374%per cycle at 1 C.Moreover,capacity still sustains 795 m Ah/g after 100 cycles in the relatively high-sulfurloading battery(6.5 mg/cm^(2)).Thus,the suggested method in configuring the sulfur-based composites is demonstrated a simple and efficient strategy to construct the high-performance Li-S batteries.展开更多
Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility.In this work,a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilizatio...Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility.In this work,a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilization of ferrocyanides modified zinc phytate into polysulfone(PSF)substrate for the treatment of Cs-contaminated water.The maximum adsorption capacity of ZnFC-PA/PSF was 305.38 mg/g,and the removal efficiency of Cs+was reached 94.27%within 2 hr.The ZnFC-PA/PSF presented favorable stability with negligible dissolution loss of Zn^(2+)and Fe^(2+)(<2%).The ZnFC-PA/PSF achieved high-selectivity towards Cs+(K_(d)=2.24×10^(4)mL/g)even in actual geothermal water.The adsorption mechanism was inferred to be the ion-exchange between Cs^(+)and K^(+).What’s more,ZnFC-PA/PSF worked well in the fixed-bed adsorption(E=91.92%),indicating the application potential for the hazardous Cs^(+)removal from wastewater.展开更多
A novel ferrite composite using rice husk as substrate has been prepared via high temperature treatment under nitrogen atmosphere.The rice husk substrate consists of porous activated carbon and silica,where spinel fer...A novel ferrite composite using rice husk as substrate has been prepared via high temperature treatment under nitrogen atmosphere.The rice husk substrate consists of porous activated carbon and silica,where spinel ferrite particles with average diameter of 59 nm are distributed.The surface area of the composite is greater than 170 m^2 g^(-1) and the bulk density is less than 0.6 g cm^(-3).Inert atmosphere is indispensable for the synthesis of pure ferrite composites,while different preparation temperatures ...展开更多
In this work,the snail shell/hydroxyapatite/chitosan composite was prepared as adsorbent.The adsorption potential of the composite was studied for simultaneous sorption behavior of Zn(Ⅱ)and Cu(Ⅱ)ions in a batch syst...In this work,the snail shell/hydroxyapatite/chitosan composite was prepared as adsorbent.The adsorption potential of the composite was studied for simultaneous sorption behavior of Zn(Ⅱ)and Cu(Ⅱ)ions in a batch system.Chitosan and hydroxyapatite(HAP)were extracted from shrimp shell and bone ash,respectively,so this is a low cost natural composite.To prepare the composite,chitosan was dissolved in acetic acid,then HAP and snail shell powders were added to the chitosan solution.The morphology and characterization of the composite was studied by SEM and EDX analysis.Atomic adsorption was used to measure the amount of the ions.Experimental parameters were optimized with Design Expert Software and five parameters such as the concentration of ions,pH,adsorbent amount and contact time were studied at room temperature.Optimized value for the parameters of Zn(Ⅱ)and Cu(Ⅱ)concentrations,pH,adsorbent dose,and contact time were 3.01 mg·L^(-1),5.5,0.02 g and 95 min,respectively.The adsorption isotherms for Zn(Ⅱ)and Cu(Ⅱ)showed Langmuir and Tempkin,respectively.Kinetic and equilibrium studies showed the experimental data of Zn(Ⅱ)and Cu(Ⅱ)ions were best described by the pseudo-second-order model.Studies on thermodynamic show the adsorption process were physical and spontaneous.展开更多
The rising production of produced water from oilfields had been proven to bring detrimental environmental effects.In this study,an efficient,recyclable,and environmental-friendly reduced graphene oxide immobilizedκ-C...The rising production of produced water from oilfields had been proven to bring detrimental environmental effects.In this study,an efficient,recyclable,and environmental-friendly reduced graphene oxide immobilizedκ-Carrageenan hydrogel composite(κCaGO)was fabricated as an alternative sorbent for crude oil-in-water demulsification.Polyethyleneimine(PEI)was employed to form a stable hydrogel composite.The conditions for the immobilization of graphene oxide(GO)on PEI-modifiedκ-Carrageenan(κC)beads were optimized appropriately.An immobilization yield of 77%was attained at 2%PEI,2 h immobilization activation time,and pH 6.5.Moreover,the synthesizedκCaGO is capable of demulsification with an average demulsification efficiency of 70%.It was found that the demulsification efficiency increases with salinity andκCaGO dosage,and it deteriorates under alkaline condition.These phenomena can be attributed to the interfacial interactions betweenκCaGO and the emulsion.Furthermore,theκCaGO can be recycled to use for up to six cycles without significant leaching and degradation.As such,the synthesizedκCaGO could be further developed as a potential sorbent substitute for the separation of crude oil from produced water.展开更多
A recyclable copper removal adsorbent was developed from diatomite and alu- minum sludge composite materials. The. effects of different formulas on the adsorption of Cu2~ under different conditions were discussed. The...A recyclable copper removal adsorbent was developed from diatomite and alu- minum sludge composite materials. The. effects of different formulas on the adsorption of Cu2~ under different conditions were discussed. The properties and rnicrostructures of the samples were characterized. The results showed that the optimum pH value, contacting time and raw materials proportion for copper removal are 6, 90 min and 40：60 （sludge： diatomite）, respectively, The copper removal capacity could reach 0.46 mg/g at the initial copper concentration of 5 mg/L. There was no change in the composition of crystal phase before and after copper removal, so physical adsorption was dominant during the adsorption process.展开更多
In this research,polyamide modified baghouse dust nanocomposite(PMBHD)was synthesized from steel industry waste using the interfacial polymerization technique.Adsorption capacities of the PMBHD were examined for the u...In this research,polyamide modified baghouse dust nanocomposite(PMBHD)was synthesized from steel industry waste using the interfacial polymerization technique.Adsorption capacities of the PMBHD were examined for the uptake of cadmium Cd(Ⅱ),lead Pb(Ⅱ),and methylene blue MB from simulated solutions.The effects of different operational factors of the adsorption,including contact time,pH,adsorbent dosage,initial concentration,and temperature,were investigated.The obtained results revealed that the equilibrium data of MB,Pb(Ⅱ),and Cd(Ⅱ)were best fitted to Dubinin-Radushkevich,Langmuir,and Freundlich isotherm.Maximum removal uptake was found to be 6.08,119,and 234 mg·g^(-1),whereas maximum removal efficiencies of 90%,99.8%,and 98%were achieved for MB,Pb(Ⅱ),and Cd(Ⅱ).Adsorption kinetics of MB and metals well-fitted to the pseudo-second-order kinetic.The characterization results showed the presence of polymeric chain on the surface of the PMBHD.The thermodynamic study revealed that the values of the free energy DG for Pb(Ⅱ)and Cd(Ⅱ)were found to be negative,which indicates spontaneous,energetic,and favorable adsorption.While for MB removal,positive values of(DG)were noticed,which implies that the adsorption was unfavorable.The proposed mechanism for the adsorption of MB and metals on the PMBHD showed that the dominating mechanism is physisorption.The adsorption/desorption results verified the high reusability of the PMBHD for adsorption of MB and metals.展开更多
Far-ranging and improper uses of pharmaceuticals and personal care products(PPCPs)over the last few decades have led to severe water contamination that imposes serious effects on human beings and the ecological system...Far-ranging and improper uses of pharmaceuticals and personal care products(PPCPs)over the last few decades have led to severe water contamination that imposes serious effects on human beings and the ecological system.Therefore,there is an increasing demand for a highly-efficient and environmentally friendly technology for the removal of PPCPs from aqueous solutions.Adsorption technology is an appropriate technology to solve this issue.Carbon-based composites,ranging from modified activated carbon to functionalized biochar,show great potential for this purpose.This review hence elaborates on the environmental occurrences and risks of PPCPs and summarizes the recent progress in removing PPCPs from water using carbon-based adsorbents.The pore structure,relatively large specific surface area(SSA),abundant surface functional groups,highly aromatic structures and the extra excellent characteristics of the cooperative materials contribute to their outstanding adsorption performance.Furthermore,the biochar-clay material is cost effective and more efficient compared to traditional activated carbon regarding the adsorption of PPCPs.Among the emerging adsorbents,graphene and carbon nanotubes composites show superior adsorption ability.Their adsorption mechanisms,such as electrostatic interactions,hydrogen bonding,and pore filling,are discussed in details.展开更多
A new composite adsorbent SiO2·xH2O·yCaCl2 which is composed of macro-porous silica gel and calcium chloride is introduced. In order to analyze its adsorption theory, adsorption and desorption isotherms, BET...A new composite adsorbent SiO2·xH2O·yCaCl2 which is composed of macro-porous silica gel and calcium chloride is introduced. In order to analyze its adsorption theory, adsorption and desorption isotherms, BET surface areas, pore volumes and average pore diameters of macro-porous silica gel and four composite adsorbent samples with different CaCl2 content are measured using SEM and Asap2010 apparatus. From the adsorption isotherms, desorption isotherms and lag loops, it can be deduced that the main pore structure in macro-porous silica gel and the new composite adsorbent have two shapes: taper with one top open and taper or hyperbolic taper with both ends open. Based on the analysis of pore diameter distribution and lag loop, a sketch map showing calcium chloride filled in pore of macro-porous silica gel is presented. The adsorption isotherms at 25°C are measured. Experimental results show that the new composite adsorbent can adsorb more water than common adsorbents (macro-porous silica gel, micro-porous silica gel and synthetic zeolite 13X). In the light of the results of pore structure, adsorption isotherms and lyolysis phenomenon are analyzed.展开更多
To solve the problem of swelling and agglomeration of CaCl2 during the process of ammonia adsorption and improve the performance of mass transfer, we present a new method for the preparation of adsorbent. The CaCl2 is...To solve the problem of swelling and agglomeration of CaCl2 during the process of ammonia adsorption and improve the performance of mass transfer, we present a new method for the preparation of adsorbent. The CaCl2 is first immerged into sawdust by soaking method, then the composite adsorbent is prepared by carbonizing the mixture of CaCl2 and sawdust. The SEM image and elements analysis indicated that the new adsorbent has high porosity and uniform distribution of CaCl2 due to carbonization under temperature of 700℃. The performance testing of ammonia adsorption showed that under the conditions of evaporation temperature of -5℃ and condensation temperature of 40℃, the ammonia uptake reaches 0.204, 0.253 and 0.285 kg/kg, the specific cooling power （SCP） is 868.96, 540.02 and 405.16 W/kg, and the average adsorption rate is 6.79×10^-4, 4.22×10^-4 and 3.17×10^-4 kg/kg/s when the adsorption time is 5, 10 and 15 min, respectively. The problems of swelling and agglomeration of CaCl2 are solved.展开更多
A novel triolein-embedded activated carbon composite adsorbent was developed. Experiments were car-ried out in areas such as the preparation method, the char-acterization of physicochemical properties, and the adsorp-...A novel triolein-embedded activated carbon composite adsorbent was developed. Experiments were car-ried out in areas such as the preparation method, the char-acterization of physicochemical properties, and the adsorp-tion behavior of the composite adsorbent in removing diel-drin from aqueous solution. Results suggested that the novel composite adsorbent was composed of the supporting acti-vated carbon and the surrounding triolein-embedded cellu-lose acetate membrane. The adsorbent was stable in water, for no triolein leakage was detected after soaking the ad-sorbent for five weeks. The adsorbent had good adsorption capability to dieldrin, which was indicated by a residual di-eldrin concentration of 0.204 μg·L?1. The removal efficiency of the composite adsorbent was higher than the traditional activated carbon adsorbent.展开更多
文摘The presence of Hg in the aqueous media is known to cause severe health issues in both humans and animals.Many technologies and especially adsorbents have been applied for its removal. In this study, a graphene oxide–carbon composite(GO–CC) as a new adsorbent was prepared by sol gel procedure and characterized using field emission scanning electron microscopy, BET and EDX. The effects of different variables including solution p H, contact time, adsorbent dose and GO ratio in adsorbent matrix on the removal capacity of Hg were studied. The isotherm data correlated well with the Langmuir isotherm model. Further analysis recommended that the Hg^(2+) adsorption process is governed by the intra-particle and external mass transfer, in which the film diffusion was the rate restrictive step. The presented composite has maximum absorption capacity, q_(max) of 68.8 mg·g^(-1), which is comparable with carbon based adsorbent reported in the previous publications.
基金Supported by the National Natural Science Foundation of China(No.50174014)
文摘A new composite adsorbent, nano-Fe3O4/bacterial cellulose（BC）, was prepared through blending method. The process of adsorbing Cd2＋ including its isotherm and kinetics measured was studied. The results show that the adsorption efficiency is improved because of huge surface area and surface coordination of nano-Fe3O4 particles. Its adsorption capacity is 27.97 mg/g and the maximum of Cd2＋ removal is 74%. The adsorption kinetics can be described by pseudo-second rate model and the adsorption equilibrium by Langmuir type. The superparamagnetism of nano-Fe3O4 particles can help to solve the difficult separation of single BC adsorbent and lead to the quick separation of composite adsorbent from the liquid if a magnetic field was applied. Cd2＋ can be desorbed effectively by EDTA and HCl from the composite adsorbent, which can make it be reused.
基金Supported by National Natural Science Foundation of China(No.51276044)Science and Technology Planning Project of Guangdong Province,China(Grant Nos.2015A050502047,2015B010135011)+3 种基金Science and Technology Planning Project of Guangzhou City,China(Grant Nos.201508030018,2016201604030040)Youth Foundation of Guangdong University of Technology,China(Grant No.252151038)EPSRC Grants(Grant Nos.EP/I027904/1,EP/K004689/1,EP/M008088/1)IChemE Global Awards 2015:MCSA for FP&VA
文摘Thermal conductivity is one of key parameters of adsorbents, which will affect the overall system performance of adsorption chiller. To improve adsorbent＇s thermal conductivity is always one of research focuses in chemisorption field. A new chemical composite adsorbent is fabricated by adding carbon coated metal（Aluminum and Nickel） nanoparticles with three different addition amounts into the mixture of chloride salts and natural expanded graphite aiming to improve the thermal conductivity. The preparation processes and its thermal conductivity of this novel composite adsorbent are reported and summarized. Experimental results indicate that the nanoparticles are homogenously dispersed in the composite adsorbent by applying the reported preparation processes. The thermal conductivity of the composite adsorbent can averagely enlarge by 20% when the weight ratio of the added nanoparticles is 10 wt%. Moreover, carbon coated aluminum nanoparticles exhibit more effective enlargement in thermal conductivity than nickel nanoparticles. As for the composite adsorbent of CaCl2-NEG, there is a big reinforcement from 30% to 50% for Al@C nanoparticles, however only 10% in maximum caused by Ni@C nanoparticles. The proposed research provides a methodology to design and prepare thermal conductive chemical composite adsorbent.
文摘This work reports the adsorption of strontium from aqueous solutions onto PAN/zeolite composite. The strontium adsorption on the composite adsorbent was studied as a function of initial strontium concentration, pH of the solution, contact time and temperature. Adsorption isotherms like Langmuir, Freundlich,Dubinin–Radushkevich (D–R) and Temkin were used to analyze the equilibrium data at the different concentrations.Adsorption process well fitted to Temkin isotherm model. Thermodynamic parameters such as the changes in enthalpy, entropy and Gibbs’ free energy were determined, showing adsorption to be an exothermic and spontaneous process.
基金financially supported by the National High Technology Research and Development Program of China (2012AA061704)
文摘As a kind of rare metals,rubidium is often used to prepare special glass,photomultiplier tubes,thermoelectric converter,organic catalysts and antidepressants.Rubidium forms no minerals of its own,hence,it often coexists with
基金supported by the Fundamental Research Funds for the Central Universities(2232020A-04)Natural Science Foundation of Shanghai City(19ZR1401300)。
文摘The protein-bound uremic toxins,represented by indoxyl sulfate(IS),have been associated with the progression of chronic kidney disease and the development of cardiovascular disease in the presence of impaired renal function.Herein,we proposed a novel strategy of thin-film nanofibrous composite(TNFC)dialysis membrane combined with reduced graphene oxide(rGO)aerogel adsorbents for clinical removal of IS as well as high retention of proteins.The TFNC membrane was prepared by electrospinning in conjunction with coating-reaction method and proved to have good selectivity and permeability.To further improve the removal rate of toxins,we used a medium hydrothermal method following by freeze-drying treatment to obtain the r GO aerogel adsorbents.It exhibited excellent adsorption for IS with a maximum adsorption capacity of 69.40 mg·g^(-1)throughπ-πinteraction and hydrogen bonding interaction based on Langmuir isotherm models.Time-dependent absorption experiments showed that it reached adsorption equilibrium within 4 h,which was matched with the hemodialysis time.The coordination was significantly exhibited by introducing r GO aerogel blocks into the dialysate for absorbing the diffused free IS during hemodialysis.Taking the advantages of the TFNC dialysis membrane and the rGO aerogel,the volume of dialysate for hemodialysis was only one-tenth of that without adsorbent blocks but with very comparable dialysis performance(the clearance of IS at 51.8%and the retention of HSA over 98%),which could lighten conventional hemodialysis effectively and be benefit to realize the miniaturization of the hemodialysis equipment.Therefore,the coordination of the TFNC dialysis membrane and rGO aerogel adsorbents would open a new path for the development of portable artificial kidney.
基金the Science and Technique Key Foundation of Guangdong Province(No.2003A1100101,2003C105006)
文摘A novel carbon-sulfur nano-composite material was synthesized by heating sublimed sulfur and high surface area activated carbon （HSAAC） under certain conditions. The physical and chemical per- formances of the novel carbon-sulfur nano-composite were characterized by scanning electron microscopy （SEM）, Brunauer-Emmett-Teller （BET） and X-ray diffraction （XRD）. The electrochemical performances of nano-composite were characterized by charge-discharge characteristic, cyclic voltammetry and electrochemical impendence spectroscopy （EIS）. The experimental results indicate that the electrochemical capability of nano- composite material was superior to that of traditional S-containing composite material. The cathode made by carbon-sulfur nano-composite material shows a good cycle ability and a high specific charge-discharge capacity. The HSAAC shows a vital role in adsorbing sublimed sulfur and the polysulfides within the cathode and is an excellent electric conductor for a sulfur cathode and prevents the shuttle behavior of the lithium-sulfur battery.
基金supported by the National Natural Science Foundation of China(No.21905289)the Independent Cultivation Program of Innovation Team of Ji’nan City(No.2019GXRC011)+1 种基金the Natural Science Foundation of Shandong Province(No.ZR2020QE062)China Postdoctoral Science Foundation(No.2021T140268)。
文摘Lithium-sulfur(Li-S)battery is labeled as a promising high-energy-density battery system,but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical applications.Herein,an integrated approach is proposed to fabricate the high-performance rGO/VS_(4)/S cathode composites through a simple one-step solvothermal method,where nano sulfur and VS_(4) particles are uniformly distributed on the conductive rGO matrix.rGO and sulfiphilic VS_(4)provide electron transfer skeleton and physical/chemical anchor for soluble lithium polysulfides(LiPS).Meanwhile,VS_(4) could also act as an electrochemical mediator to efficiently enhance the utilization and reversible conversion of LiPS.Correspondingly,the rGO/VS_(4)/S composites maintain a high reversible capacity of 969 mAh/g at 0.2 C after 100 cycles,with a capacity retention rate of 82.3%.The capacity fade rate could lower to 0.0374%per cycle at 1 C.Moreover,capacity still sustains 795 m Ah/g after 100 cycles in the relatively high-sulfurloading battery(6.5 mg/cm^(2)).Thus,the suggested method in configuring the sulfur-based composites is demonstrated a simple and efficient strategy to construct the high-performance Li-S batteries.
基金supported by the National Natural Science Foundation of China(Nos.22203062,22078247,U1707602,U1507109)the Yangtze Scholars and Innovative Research Team in University of Ministry of Education of China(No.IRT17R81)。
文摘Radioisotope leaking from nuclear waste has become an intractable problem due to its gamma radiation and strong water solubility.In this work,a novel porous ZnFC-PA/PSF composite sphere was fabricated by immobilization of ferrocyanides modified zinc phytate into polysulfone(PSF)substrate for the treatment of Cs-contaminated water.The maximum adsorption capacity of ZnFC-PA/PSF was 305.38 mg/g,and the removal efficiency of Cs+was reached 94.27%within 2 hr.The ZnFC-PA/PSF presented favorable stability with negligible dissolution loss of Zn^(2+)and Fe^(2+)(<2%).The ZnFC-PA/PSF achieved high-selectivity towards Cs+(K_(d)=2.24×10^(4)mL/g)even in actual geothermal water.The adsorption mechanism was inferred to be the ion-exchange between Cs^(+)and K^(+).What’s more,ZnFC-PA/PSF worked well in the fixed-bed adsorption(E=91.92%),indicating the application potential for the hazardous Cs^(+)removal from wastewater.
基金supported by National High Technology Research and Development(863) Program of China(No.2007AA06Z128).
文摘A novel ferrite composite using rice husk as substrate has been prepared via high temperature treatment under nitrogen atmosphere.The rice husk substrate consists of porous activated carbon and silica,where spinel ferrite particles with average diameter of 59 nm are distributed.The surface area of the composite is greater than 170 m^2 g^(-1) and the bulk density is less than 0.6 g cm^(-3).Inert atmosphere is indispensable for the synthesis of pure ferrite composites,while different preparation temperatures ...
文摘In this work,the snail shell/hydroxyapatite/chitosan composite was prepared as adsorbent.The adsorption potential of the composite was studied for simultaneous sorption behavior of Zn(Ⅱ)and Cu(Ⅱ)ions in a batch system.Chitosan and hydroxyapatite(HAP)were extracted from shrimp shell and bone ash,respectively,so this is a low cost natural composite.To prepare the composite,chitosan was dissolved in acetic acid,then HAP and snail shell powders were added to the chitosan solution.The morphology and characterization of the composite was studied by SEM and EDX analysis.Atomic adsorption was used to measure the amount of the ions.Experimental parameters were optimized with Design Expert Software and five parameters such as the concentration of ions,pH,adsorbent amount and contact time were studied at room temperature.Optimized value for the parameters of Zn(Ⅱ)and Cu(Ⅱ)concentrations,pH,adsorbent dose,and contact time were 3.01 mg·L^(-1),5.5,0.02 g and 95 min,respectively.The adsorption isotherms for Zn(Ⅱ)and Cu(Ⅱ)showed Langmuir and Tempkin,respectively.Kinetic and equilibrium studies showed the experimental data of Zn(Ⅱ)and Cu(Ⅱ)ions were best described by the pseudo-second-order model.Studies on thermodynamic show the adsorption process were physical and spontaneous.
基金The authors would like to acknowledge for the financial supports given by Fundamental Research Grant Scheme (FRGS/1/2019/TK02/CURTIN/03/2) from Ministry of Higher Education (MOHE),Malaysia.
文摘The rising production of produced water from oilfields had been proven to bring detrimental environmental effects.In this study,an efficient,recyclable,and environmental-friendly reduced graphene oxide immobilizedκ-Carrageenan hydrogel composite(κCaGO)was fabricated as an alternative sorbent for crude oil-in-water demulsification.Polyethyleneimine(PEI)was employed to form a stable hydrogel composite.The conditions for the immobilization of graphene oxide(GO)on PEI-modifiedκ-Carrageenan(κC)beads were optimized appropriately.An immobilization yield of 77%was attained at 2%PEI,2 h immobilization activation time,and pH 6.5.Moreover,the synthesizedκCaGO is capable of demulsification with an average demulsification efficiency of 70%.It was found that the demulsification efficiency increases with salinity andκCaGO dosage,and it deteriorates under alkaline condition.These phenomena can be attributed to the interfacial interactions betweenκCaGO and the emulsion.Furthermore,theκCaGO can be recycled to use for up to six cycles without significant leaching and degradation.As such,the synthesizedκCaGO could be further developed as a potential sorbent substitute for the separation of crude oil from produced water.
基金Supported by the National Natural Science Foundation of China (No.51102047)Fujian Natural Science Foundation for Distinguished Youth Scholars (2012J06011)National Undergraduate Practice Innovation Plan (121038632)
文摘A recyclable copper removal adsorbent was developed from diatomite and alu- minum sludge composite materials. The. effects of different formulas on the adsorption of Cu2~ under different conditions were discussed. The properties and rnicrostructures of the samples were characterized. The results showed that the optimum pH value, contacting time and raw materials proportion for copper removal are 6, 90 min and 40：60 （sludge： diatomite）, respectively, The copper removal capacity could reach 0.46 mg/g at the initial copper concentration of 5 mg/L. There was no change in the composition of crystal phase before and after copper removal, so physical adsorption was dominant during the adsorption process.
文摘In this research,polyamide modified baghouse dust nanocomposite(PMBHD)was synthesized from steel industry waste using the interfacial polymerization technique.Adsorption capacities of the PMBHD were examined for the uptake of cadmium Cd(Ⅱ),lead Pb(Ⅱ),and methylene blue MB from simulated solutions.The effects of different operational factors of the adsorption,including contact time,pH,adsorbent dosage,initial concentration,and temperature,were investigated.The obtained results revealed that the equilibrium data of MB,Pb(Ⅱ),and Cd(Ⅱ)were best fitted to Dubinin-Radushkevich,Langmuir,and Freundlich isotherm.Maximum removal uptake was found to be 6.08,119,and 234 mg·g^(-1),whereas maximum removal efficiencies of 90%,99.8%,and 98%were achieved for MB,Pb(Ⅱ),and Cd(Ⅱ).Adsorption kinetics of MB and metals well-fitted to the pseudo-second-order kinetic.The characterization results showed the presence of polymeric chain on the surface of the PMBHD.The thermodynamic study revealed that the values of the free energy DG for Pb(Ⅱ)and Cd(Ⅱ)were found to be negative,which indicates spontaneous,energetic,and favorable adsorption.While for MB removal,positive values of(DG)were noticed,which implies that the adsorption was unfavorable.The proposed mechanism for the adsorption of MB and metals on the PMBHD showed that the dominating mechanism is physisorption.The adsorption/desorption results verified the high reusability of the PMBHD for adsorption of MB and metals.
基金supported by the National Natural Science Foundation of China(No.51778230)Program of Shanghai Outstanding Technology Leaders(No.20XD1433900)。
文摘Far-ranging and improper uses of pharmaceuticals and personal care products(PPCPs)over the last few decades have led to severe water contamination that imposes serious effects on human beings and the ecological system.Therefore,there is an increasing demand for a highly-efficient and environmentally friendly technology for the removal of PPCPs from aqueous solutions.Adsorption technology is an appropriate technology to solve this issue.Carbon-based composites,ranging from modified activated carbon to functionalized biochar,show great potential for this purpose.This review hence elaborates on the environmental occurrences and risks of PPCPs and summarizes the recent progress in removing PPCPs from water using carbon-based adsorbents.The pore structure,relatively large specific surface area(SSA),abundant surface functional groups,highly aromatic structures and the extra excellent characteristics of the cooperative materials contribute to their outstanding adsorption performance.Furthermore,the biochar-clay material is cost effective and more efficient compared to traditional activated carbon regarding the adsorption of PPCPs.Among the emerging adsorbents,graphene and carbon nanotubes composites show superior adsorption ability.Their adsorption mechanisms,such as electrostatic interactions,hydrogen bonding,and pore filling,are discussed in details.
文摘A new composite adsorbent SiO2·xH2O·yCaCl2 which is composed of macro-porous silica gel and calcium chloride is introduced. In order to analyze its adsorption theory, adsorption and desorption isotherms, BET surface areas, pore volumes and average pore diameters of macro-porous silica gel and four composite adsorbent samples with different CaCl2 content are measured using SEM and Asap2010 apparatus. From the adsorption isotherms, desorption isotherms and lag loops, it can be deduced that the main pore structure in macro-porous silica gel and the new composite adsorbent have two shapes: taper with one top open and taper or hyperbolic taper with both ends open. Based on the analysis of pore diameter distribution and lag loop, a sketch map showing calcium chloride filled in pore of macro-porous silica gel is presented. The adsorption isotherms at 25°C are measured. Experimental results show that the new composite adsorbent can adsorb more water than common adsorbents (macro-porous silica gel, micro-porous silica gel and synthetic zeolite 13X). In the light of the results of pore structure, adsorption isotherms and lyolysis phenomenon are analyzed.
基金supported by the Chinese Academy of Sciences and Foreign Experts Bureau of Guangdong under the Adsorption Refrigeration Program (Grant nos. y007y51001 and 2010004)The structure and preparation process of the new adsorbent has a patent (China Patent 20111015-1114.2)
文摘To solve the problem of swelling and agglomeration of CaCl2 during the process of ammonia adsorption and improve the performance of mass transfer, we present a new method for the preparation of adsorbent. The CaCl2 is first immerged into sawdust by soaking method, then the composite adsorbent is prepared by carbonizing the mixture of CaCl2 and sawdust. The SEM image and elements analysis indicated that the new adsorbent has high porosity and uniform distribution of CaCl2 due to carbonization under temperature of 700℃. The performance testing of ammonia adsorption showed that under the conditions of evaporation temperature of -5℃ and condensation temperature of 40℃, the ammonia uptake reaches 0.204, 0.253 and 0.285 kg/kg, the specific cooling power （SCP） is 868.96, 540.02 and 405.16 W/kg, and the average adsorption rate is 6.79×10^-4, 4.22×10^-4 and 3.17×10^-4 kg/kg/s when the adsorption time is 5, 10 and 15 min, respectively. The problems of swelling and agglomeration of CaCl2 are solved.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.50578154,20337020)the Hi-Tech Research and Development Program of China(Grant No.2005AA642020).
文摘A novel triolein-embedded activated carbon composite adsorbent was developed. Experiments were car-ried out in areas such as the preparation method, the char-acterization of physicochemical properties, and the adsorp-tion behavior of the composite adsorbent in removing diel-drin from aqueous solution. Results suggested that the novel composite adsorbent was composed of the supporting acti-vated carbon and the surrounding triolein-embedded cellu-lose acetate membrane. The adsorbent was stable in water, for no triolein leakage was detected after soaking the ad-sorbent for five weeks. The adsorbent had good adsorption capability to dieldrin, which was indicated by a residual di-eldrin concentration of 0.204 μg·L?1. The removal efficiency of the composite adsorbent was higher than the traditional activated carbon adsorbent.
