Separating oil/water mixtures via superhydrophobic stainless steel mesh(SSM)is a kind of efficient methods of treating oily wastewater,and the superhydrophobic SSM with a low cost,simple fabrication process and robust...Separating oil/water mixtures via superhydrophobic stainless steel mesh(SSM)is a kind of efficient methods of treating oily wastewater,and the superhydrophobic SSM with a low cost,simple fabrication process and robust usability remains a challenge.Herein,urushiol-based benzoxazine(U-D)with a strong substrate adhesion and low surface free energy was used to anchor SiO_(2) particles on the SSM surface to obtain a durable superhydrophobic SSM(PU-D/SiO_(2)/SSM)through a simple dip-coating process,meanwhile,epoxy resin was also introduced to further improve the adhesion between coating and SSM.PU-D/SiO_(2)/SSM could successfully separate various immiscible oil-water mixtures with a separation efficiency of over 96%and a flux up to 27100 L/m^(2) h only by gravity,respectively.Especially,the modified SSM could effectively remove water from water-in-oil emulsion with a separation efficiency of 99.7%.Moreover,PU-D/SiO_(2)/SSM had an outstanding reusability,whose water contact angle and separation efficiency only slightly decreased after 20 cycles of separating oil/water mixture.In addition,the modified SSM also displayed a satisfactory abrasion resistance,chemical stability and self-cleaning property.Thereby,the robust PU-D/SiO_(2)/SSM prepared by cheap raw materials and facile dip-coating method exhibits a high potential for separating oil/water mixtures.展开更多
Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-...Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading.展开更多
The crisis of excessive increase in CO_(2)emissions has quickly become a serious issue and requires low-cost and bio-compatible solutions.The employee of membrane technology for CO_(2)gas separation has garnered signi...The crisis of excessive increase in CO_(2)emissions has quickly become a serious issue and requires low-cost and bio-compatible solutions.The employee of membrane technology for CO_(2)gas separation has garnered significant interest among researchers.However,this method encounters challenges related to selectivity and permeability.Therefore,modifying and reinforcing the polymer membranes to improve gas separation performance seems essential.Among the various methods for polymer membrane modification,modification with magnesium-based fillers to prepare a mixed matrix membrane(MMM)is considered an efficient method.Owing to magnesium metal's low weight,low density,high strength,and good selectivity,magnesium-based materials(Mg-based materials)have more porosity,higher available surface area,more adsorption sites,lighter weight,and more gas absorption tendency than other fillers,which makes them an attractive choice for the preparation of gas separation MMMs.This research deals with the introduction of Mg-based materials,various methods of synthesis of Mg-based materials,different methods of introducing Mg-based materials into the membrane matrix,and their effect on the performance of MMMs in CO_(2)gas separation applications.Therefore,this review can provide researchers with light horizons in using the high potential of Mg-based materials as efficient fillers in MMMs to achieve excellent permeability and selectivity and generally improve their performance in CO_(2)gas separation applications.展开更多
Due to the similar physicochemical properties of acetylene(C_(2)H_(2))and carbon dioxide(CO_(2)),separating C_(2)H_(2)from a CO_(2)/C_(2)H_(2)mixture poses a significant challenge in the petrochemical industry.Herein,...Due to the similar physicochemical properties of acetylene(C_(2)H_(2))and carbon dioxide(CO_(2)),separating C_(2)H_(2)from a CO_(2)/C_(2)H_(2)mixture poses a significant challenge in the petrochemical industry.Herein,we successfully synthesized a novel SiF_(6)^(2) anion pillared cage metal-organic framework ZNU-15 possessing a new crs topological structure for the selective capture of C_(2)H_(2).As a linear bidentate linker,the fluorinated SiF_(6)^(2) anion partitions the pores into various sized cages.ZNU-15 displays moderate adsorption for C_(2)H_(2)with a capacity of 36.0 cm^(3)g^(-1)at 298 K and 1 bar,which is 2.7 times higher than the CO_(2)uptake.The IAST selectivity of C_(2)H_(2)/CO_(2)for ZNU-15 at 298 K and 100 kPa is 10.5,surpassing that of most reported materials.The Qst values for C_(2)H_(2)and CO_(2)at zero coverage are 54.0 and 42.8 kJ mol^(-1),respectively.Moreover,breakthrough experimental tests show that ZNU-15 is capable of effectively separating C_(2)H_(2)from a C_(2)H_(2)/CO_(2)mixture.Theoretical calculations further indicate that C_(2)H_(2)is preferentially trapped by the small cage with four cooperative hydrogen bonds.展开更多
The production of high-purity H_(2) is the building block of hydrogen economy,which can greatly promote the construction of related technologies and infrastructure.Efficient H_(2)/CH_(4) separation is a necessary unit...The production of high-purity H_(2) is the building block of hydrogen economy,which can greatly promote the construction of related technologies and infrastructure.Efficient H_(2)/CH_(4) separation is a necessary unit in producing high-purity energy and reducing greenhouse gas emissions,which can meet the industrial demand and help to address the energy issue and achieve global carbon neutrality goals.Membrane separation technology,as a promising strategy for H_(2) purification,has attracted much attention due to its high efficiency,energy conservation and versatile applications.This article reviews the latest research advances in the high-performance membranes for H_(2)/CH_(4) separation,and elu-cidates the effect of membrane materials,preparation methods and membrane structure on separation performance from the perspective of separation mechanisms.It also summarized the essential aspects of membrane design,such as microstructural regulation,multiphase coupling,the optimal usage conditions and simple analysis of economic benefits.Finally,the current challenges and future directions of membranes for H_(2)/CH_(4) separation were discussed,intending to provide in-depth reference and inspiration for the theoretical research and practical application of membrane separation technology.展开更多
Achieving efficient adsorption and separation of C_(2)H_(2)/CO_(2)mixtures is a goal that people have always pursued to improve the situation of high energy consumption brought by traditional separation technologies i...Achieving efficient adsorption and separation of C_(2)H_(2)/CO_(2)mixtures is a goal that people have always pursued to improve the situation of high energy consumption brought by traditional separation technologies in industry today.High-nuclearity metal cluster-based MOFs with different functionalities are promising for this separation,but it is a complicated and difficult task to precisely control their structures.The strategy of pore-space partition(PSP)is a powerful way to construct this type MOFs,which has the characteristic of isostructural relationship,and can be resulted in a similar performance for them.Therefore,it is an interesting work to explore the effect of MOFs property by adjusting the size of PSP dividers.Herein,three tetranuclear Cu(Ⅱ)cluster-based MOFs(FJU-112/113/114)with dual functionalities has been successfully obtained by PSP strategy with various lengths of divider units.With the highest microporosity and unique functional site,FJU-114 realized a good improvement in the adsorption and separation performance of C_(2)H_(2)/CO_(2).The gas adsorption and lab-scale C_(2)H_(2)/CO_(2)breakthrough experiments demonstrated that FJU-114 exhibits the highest adsorption uptake of 77 cm^(3)/g for C_(2)H_(2),and shows the best separation factor of 4.2 among three MOFs.The GCMC simulation reveals that a stronger adsorption binding site of C_(2)H_(2)in FJU-114a located in the cage II near the unchanged tetranuclear copper node,combined with its high microporosity to achieve the effect of dual functionalities for the improvement performance of C_(2)H_(2)adsorption and separation.展开更多
Zeolitic imidazole frameworks(ZIFs)are a class of three-dimensional(3D)skeletalmaterials with zeolitic topology composed of metal ions and imidazolium ligands,which combine the advantages of zeolites and metal-organic...Zeolitic imidazole frameworks(ZIFs)are a class of three-dimensional(3D)skeletalmaterials with zeolitic topology composed of metal ions and imidazolium ligands,which combine the advantages of zeolites and metal-organic frameworks.ZIFs are widely used for adsorption of carbon dioxide(CO_(2))from flue gas due to its excellent hydrophobicity,chemical stability,thermal stability and gas adsorption properties.This study focuses on the effects of structures of ZIFs on CO_(2)capture and separation from the viewpoints of topologies,pore channels,ligand functional groups and composite structures.On this basis,the mechanisms of CO_(2)adsorption and selective separation are reviewed,as well as the challenges such as hydrophobicity,thermal and chemical stability faced by ZIFs in practical applications.展开更多
One of the main challenges in oil-water separation of traditional Chinese medicines(TCM)is to obtain essential oils from the aromatic water of TCM.In this study,silicon dioxide/polyvinylidene fluoride(SiO_(2)/PVDF)mem...One of the main challenges in oil-water separation of traditional Chinese medicines(TCM)is to obtain essential oils from the aromatic water of TCM.In this study,silicon dioxide/polyvinylidene fluoride(SiO_(2)/PVDF)membranes were prepared using nonsolvent induce phase separation.Then polydimethylsiloxane(PDMS)was coated to obtain PDMS/SiO_(2/)PVDF membranes.Separated essential oils and water from aromatic water in the gaseous state by vapor permeation membrane separation technology.The relationship between membrane structure and membrane separation effect was investigated.Response surface methodology was used to develop a quadratic model for the separation factor,membrane permeation separation index and membrane preparation process.The optimal process parameters for the membrane separation were 12.31%(mass)concentration of PVDF solution,9.6%(mass)of N,Ndimethylacetamide in the solidification bath,and 0.2 g hydrophobic nano-SiO_(2)incorporation,with a separation factor of 14.45,and a membrane flux of 1203.04 g·m^(-2)·h^(-1).Compared with the PDMS/PVDF membranes,the separation factor and membrane flux were increased by 68.59%and 3.46%,respectively.Compared with the SiO_(2)/PVDF membranes,the separation factor and membrane flux were increased by478%and 79.33%,respectively.Effectively mitigated the limitations of traditional polymer membrane material performance affected by the"trade-off"effect.Attenuated total internal reflection-Fourier transform infrared spectroscopy,contact angle,scanning electron microscopy and energy dispersive spectroscopy were used to characterize the PDMS/SiO_(2)/PVDF membranes,and gas chromatography was used to characterize the permeate.In addition,the contents of L-menthol,L-menthone,menthyl acetate and limonene in the permeate,conformed to the European Pharmacopoeia standards.This study provided an effective preparation strategy of a feasible hydrophobic powder polymer membrane for the separation of essential oils from gaseous peppermint aromatic water.展开更多
The lime-Cu^(2+)-xanthate process is commonly used for the flotation separation of sphalerite from pyrite.In this process,lime is added to the pulp to inhibit the floatability of pyrite.However,the excessive use of li...The lime-Cu^(2+)-xanthate process is commonly used for the flotation separation of sphalerite from pyrite.In this process,lime is added to the pulp to inhibit the floatability of pyrite.However,the excessive use of lime can result in pipeline blockage and inadequate recovery of associated precious metals.Therefore,it is necessary to develop new flotation process that minimizes or eliminates the use of lime.In this paper,a novel Fe^(3+)-Cu^(2+)-butyl xanthate process was developed as an alternative to lime for separating of sphalerite from pyrite.The flotation results indicated that with the artificially-mixed minerals,the flotation recovery of pyrite was lower than 16%and that of sphalerite was higher than 47%at pH 5.0−10.0.The zeta potential measurements revealed that ferric ion preferred to adsorb on pyrite,and copper ion displaced with zinc ion from the lattice at the interface of sphalerite.The wettability analyses indicated that the hydrophobicity of sphalerite surface increased apparently after being treated with Fe^(3+)-Cu^(2+)-BX,while the hydrophobicity of pyrite surface remained nearly unchanged.With XPS analysis,Cu-S bond and hydrophilic ferric hydroxide were detected separately on the surface of sphalerite and pyrite after conditioning with Fe^(3+)-Cu^(2+)-BX,which facilitated the flotation separation of sphalerite from pyrite with butyl xanthate collector.展开更多
In this study,Pebax■2533 polymer was used as the continuous phase and UiO-67 was employed as the filler to prepare mixed matrix membranes.UiO-67 is usually synthesized using two ligands:biphenyl-4,4'-dicarboxylat...In this study,Pebax■2533 polymer was used as the continuous phase and UiO-67 was employed as the filler to prepare mixed matrix membranes.UiO-67 is usually synthesized using two ligands:biphenyl-4,4'-dicarboxylate(bpdc)and 2,2'-bipyridine-5,5'-dicarboxylic acid(bpy).In this research,UiO-67 was synthesized not only with these two ligands but also using a mixed ligand approach(50% bpdc and 50% bpy).The synthesized UiOs were incorporated into the polymer matrix at mass percentages ranging from 0% to 2% to form the mixed matrix membranes(MMMs).Membranes containing UiO-67 with mixed ligands exhibited a greater affinity for CO_(2) compared to other membranes.Various analytical techniques,including X-ray diffraction,thermogravimetric analyzer,Fourier transform infrared spectroscope(FTIR),field emission scanning electron micro scope(FESEM),and differential scanning calorimetry,were used to analyze the properties of the prepared membranes.The FTIR spectrum confirmed all desired bands of Pebax?2533 and UiO-67 in the MMMs.The FESEM images showed that the pure Pebax membrane has a uniform structure,and the developed membranes are uniformly incorporated with the synthesized UiO-67 nanoparticles.Gas permeation measurements indicated that CO_(2) permeability and CO_(2)/CH_4 selectivity increased from 402.7 Barrer(1 Barrer=1.33×10^(-14)m^(3)(STP)·m·m^(-2)·s^(-1)·kPa^(-1))and 9.32 for the pure Pebax membrane at 1.0 MPa to 770.1 Barrer and 16.96 in the modified membrane.Additionally,the gas permeation test results demonstrated that adding functionalized porous nanofillers increases the CO_(2)separation performance.Permeability tests at different temperatures revealed that as temperature was raised,at constant pressure,CO_(2) permeability for the membrane containing the mixed ligand increased from 682.2 Barrer to 733.5 Barrer,While CO_(2)/CH_(4) selectivity decreased from 15.46 to 13.43.展开更多
Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is...Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is particularly significant in challenging coupled systems,such as CO_(2)photoreduction integrated with selective oxidation of toluene to benzaldehyde.However,developing such a system is quite challenging and often requires a precise design and engineering.Herein,we demonstrate a unique Ni-CdS@Ni(OH)_(2)heterojunction synthesized via an in-situ self-assembly method.Comprehensive mechanistic and theoretical investigations reveal that the NiCdS@Ni(OH)_(2)heterojunction induces dual electric fields(EFs):an intrinsic polarized electric-field within the CdS lattice from Ni doping and an interfacial electric-field from the growth of ultrathin nanosheets of Ni(OH)_(2)on NiCdS nanorods,enabling efficient spatial charge separation and enhanced redox potential.As proof of concept,the Ni-CdS@Ni(OH)_(2)heterojunction simultaneously exhibits outstanding bifunctional photocatalytic performance,producing CO at a rate of 427μmol g^(-1)h^(-1)and selectively oxidizing toluene to benzaldehyde at a rate of 1476μmol g^(-1)h^(-1)with a selectivity exceeding 85%.This work offers a promising strategy to optimize the utilization of photogenerated carriers in heterojunction photocatalysts,advancing synergistic photocatalytic redox systems.展开更多
Covalent organic skeletons(COFs)have been widely used in gas separation due to their excellent pore structure,high crystallinity,and high specific surface area.In this work,Dha Tab-COF was synthesized by solvothermal ...Covalent organic skeletons(COFs)have been widely used in gas separation due to their excellent pore structure,high crystallinity,and high specific surface area.In this work,Dha Tab-COF was synthesized by solvothermal method and filled in polyether block polyamide(PEBAX)to form mixed matrix membranes(MMMs).Various characterization methods such as Fourier transform infrared spectroscopy(FT-IR),Xray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM)and X-ray diffractometry(XRD)were used to characterize the structure of Dha Tab-COF as well as the MMMs.The effects of operating pressure,operating temperature and the content of Dha Tab-COF particles on the CO_(2)/CH_(4)separation performance of the membranes were investigated.The best separation performance with a CO_(2)permeability of 295.8 barrer(1 barrer=7.52×10^(-18)m^(3)·(STP)·m^(-2)·m·s^(-1)·Pa^(-1))and a CO_(2)/CH_(4)selectivity of 21.6 was achieved when the Dha Tab-COF content is 2%(mass),which were 45.7%and 108.1%higher than that of the pure PEBAX membrane,respectively.展开更多
CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hi...CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hindered by poor charge separation efficiency.Herein,we introduce a characteristic in-situ solution Fe-doping strategy that markedly improves photoelectrochemical performance of CBO,doubling the photocurrent density and achieving an unprecedented 190 mV anodic shift in the onset potential.By integrating with an electrochemical oxidation post-treatment,a record incident photon-to-current efficiency(IPCE)exceeding 40% at 0.6 V vs.RHE under visible light illumination is achieved.The versatility of the doping strategy is demonstrated across CBO photocathodes synthesized by different methods with various morphologies,grain sizes,and crystallinities.Mechanistic studies reveal that the gradient distribution of Fe^(3+)ions generates an internal electric field that facilitates efficient charge separation and increases acceptor density.The strong Fe-O bonding also enhances structural stability against photoinduced corrosion.Notably,our investigation uncovers the non-temperature-dependent nature of CBO photocurrent,indicating that PEC performance enhancement primarily depends on reducing carrier recombination rather than improving bulk conductivity.This work lays the groundwork for future advancements in water splitting performance of CBO photocathodes,offering a complementary strategy to conventional methods for enhancing charge separation efficiency.展开更多
In this paper, poly（amide-6-b-ethylene oxide） （Pebax1657）/SAPO-34 mixed matrix membranes （MMMs） were prepared by solvent-evaporation method with acetic acid as a novel solvent. CO2, N2, CH4 and H2 permeation pro...In this paper, poly（amide-6-b-ethylene oxide） （Pebax1657）/SAPO-34 mixed matrix membranes （MMMs） were prepared by solvent-evaporation method with acetic acid as a novel solvent. CO2, N2, CH4 and H2 permeation properties were investigated, and the physical properties of Pebax/SAPO-34 MMMs were characterized by XRD and SEM. At low SAPO-34 content, it was homogeneously distributed in the Pebax ma- trix, and then precipitated and agglomerated at high SAPO-34 content. The crystallinity of Pebax phase in Pebax/SAPO-34 MMMs decreased initially and then rebounded as a result of phase separation. With the increase of transmembrane pressure difference, CO2 permeability was en- hanced due to the effect of pressure-induced plasticization. Owing to the happening of stratification, the CO2 permeability of Pebax/SAPO-34 MMMs （50 wt% SAPO-34） increased to 338 Barrer from 111 Barrer of pristine Pebax, while the selectivities of CO2/CH4 and CO2/N2 were almost unchanged. Compared with the pristine Pebax, the gas separation performances of Pebax/SAPO-34 MMMs were remarkably enhanced.展开更多
Membrane separation technology has popularized rapidly and attracts much interest in gas industry as a promising sort of newly chemical separation unit operation. In this paper, recent advances on membrane processes f...Membrane separation technology has popularized rapidly and attracts much interest in gas industry as a promising sort of newly chemical separation unit operation. In this paper, recent advances on membrane processes for CO_2 separation are reviewed. The researches indicate that the optimization of operating process designs could improve the separation performance, reduce the energy consumption and decrease the cost of membrane separation systems. With the improvement of membrane materials recently,membrane processes are beginning to be competitive enough for CO_2 separation, especially for postcombustion CO_2 capture, biogas upgrading and natural gas carbon dioxide removal, compared with the traditional separation methods. We summarize the needs and most promising research directions for membrane processes for CO_2 separation in current and future membrane applications. As the time goes by, novel membrane materials developed according to the requirement proposed by process optimization with increased selectivity and/or permeance will accelerate the industrialization of membrane process in the near future. Based on the data collected in a pilot scale test, more effort could be made on the optimization of membrane separation processes. This work would open up a new horizon for CO_2 separation/Capture on Carbon Capture Utilization and Storage(CCUS).展开更多
In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane a...In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane and nanocomposite membranes were prepared via solution casting and solution blending methods, respectively. The fabricated membranes were characterized by field emission scanning electron microscopy（FESEM） to survey cross-sectional morphologies and thermal gravimetric analysis（TGA）to study thermal stability. Fourier transform infrared（FT-IR） and X-ray diffraction（XRD） analyses were also employed to identify variations of the chemical bonds and crystal structure of the membranes, respectively. Permeation of pure gases, CO, CHand Nthrough the prepared neat and nanocomposite membranes was studied at pressures of 3–18 bar and temperature of 25 °C. The obtained results showed that the fabricated nanocomposite membranes exhibit better separation performance compared to the neat PEBAX membrane in terms of both permeability and selectivity. As an example, at temperature of 25 °C and pressure of 3 bar, COpermeability, ideal CO/CHand CO/Nselectivity values for the neat PEBAX membrane are 110.67 Barrer, 11.09 and 50.08, respectively, while those values are 152.27 Barrer,13.52 and 62.15 for PEBAX/ZnO nanocomposite membrane containing 8 wt% ZnO.展开更多
Ionic liquids （ILs） have been regarded as the potential novel solvents for improved analytical- and process-scale separation methods.The development of methods for the recovery of ILs from aqueous solutions to escap...Ionic liquids （ILs） have been regarded as the potential novel solvents for improved analytical- and process-scale separation methods.The development of methods for the recovery of ILs from aqueous solutions to escape contamination and recycle samples will ultimately govern the viability of ILs in the future industrial applications. Therefore, in this paper a new method for separation of ILs from their dilute aqueous solutions and simultaneously purification of water was proposed on the basis of the CO2 hydrate formation. For illustration, the dilute aqueous solutions with concentrations of ILs ranging from 2× 10^-3 mol% to 2×10^-1 mol% were concentrated. The results show that the separation efficiency is very impressive and that the new method is applicable to aqueous solutions of both hydrophobic and hydrophilic ILs. Compared to the literature separation method based on the supercritical CO2, the new method is applicable to lower concentrations, and more importantly, its operation condition is mild.展开更多
Novel porous aromatic frameworks（PAF-53 and PAF-54） have been obtained by the polymerization of amino compound（p-phenylenediamine and melamine） and cyanuric chloride. They display a certain amount of CO2 adsorptio...Novel porous aromatic frameworks（PAF-53 and PAF-54） have been obtained by the polymerization of amino compound（p-phenylenediamine and melamine） and cyanuric chloride. They display a certain amount of CO2 adsorption capacity and highly selective separation of CO2/CH4 and CO2/N2 as 18.1 and83 by Henry Law respectively. They may be applied as ideal adsorbents to separate and capture CO2.展开更多
The process of an O2//CO2 power plant based on chemical looping air separation （CLAS） is modeled using the Aspen Plus software. The operating parameters and power consumption of the CLAS unit are analyzed. The CLAS ...The process of an O2//CO2 power plant based on chemical looping air separation （CLAS） is modeled using the Aspen Plus software. The operating parameters and power consumption of the CLAS unit are analyzed. The CLAS system, thermal power generation system and flue gas cooling and compression unit （CCU） are coupled and optimized, and the temperature and flow of the flue gas extraction are determined. The results indicate that the net plant efficiency of CLAS O2/CO2 power plant is 39.2%, which is only 3.54% lower than that of the conventional power plants without carbon capture. However, the O2/CO2 power plant based on cryogenic air separation technology brings 8% to 10% decrease in the net plant efficiency. By optimizations, the net plant efficiency increases by 1.65%. The energy consumption of the CCU accounts for 59.7% and the pump accounts for 27.1%. The oxygen concentration from the chemical looping air separation unit is 12.2%.展开更多
This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristic...This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption （PSA）, chemical absorption （CA）, and membrane absorption （MA）. Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA.展开更多
基金Funded by the National Natural Science Foundation of China(No.22165019)。
文摘Separating oil/water mixtures via superhydrophobic stainless steel mesh(SSM)is a kind of efficient methods of treating oily wastewater,and the superhydrophobic SSM with a low cost,simple fabrication process and robust usability remains a challenge.Herein,urushiol-based benzoxazine(U-D)with a strong substrate adhesion and low surface free energy was used to anchor SiO_(2) particles on the SSM surface to obtain a durable superhydrophobic SSM(PU-D/SiO_(2)/SSM)through a simple dip-coating process,meanwhile,epoxy resin was also introduced to further improve the adhesion between coating and SSM.PU-D/SiO_(2)/SSM could successfully separate various immiscible oil-water mixtures with a separation efficiency of over 96%and a flux up to 27100 L/m^(2) h only by gravity,respectively.Especially,the modified SSM could effectively remove water from water-in-oil emulsion with a separation efficiency of 99.7%.Moreover,PU-D/SiO_(2)/SSM had an outstanding reusability,whose water contact angle and separation efficiency only slightly decreased after 20 cycles of separating oil/water mixture.In addition,the modified SSM also displayed a satisfactory abrasion resistance,chemical stability and self-cleaning property.Thereby,the robust PU-D/SiO_(2)/SSM prepared by cheap raw materials and facile dip-coating method exhibits a high potential for separating oil/water mixtures.
基金sponsored by the National Natural Science Foundation of China (Nos. 22308145, 22208140, 22178159, 22078145)Natural Science Foundation of Jiangsu Province (BK20230791)Postgraduate Research Innovation Program of Jiangsu Province (KYCX24_0165)。
文摘Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading.
文摘The crisis of excessive increase in CO_(2)emissions has quickly become a serious issue and requires low-cost and bio-compatible solutions.The employee of membrane technology for CO_(2)gas separation has garnered significant interest among researchers.However,this method encounters challenges related to selectivity and permeability.Therefore,modifying and reinforcing the polymer membranes to improve gas separation performance seems essential.Among the various methods for polymer membrane modification,modification with magnesium-based fillers to prepare a mixed matrix membrane(MMM)is considered an efficient method.Owing to magnesium metal's low weight,low density,high strength,and good selectivity,magnesium-based materials(Mg-based materials)have more porosity,higher available surface area,more adsorption sites,lighter weight,and more gas absorption tendency than other fillers,which makes them an attractive choice for the preparation of gas separation MMMs.This research deals with the introduction of Mg-based materials,various methods of synthesis of Mg-based materials,different methods of introducing Mg-based materials into the membrane matrix,and their effect on the performance of MMMs in CO_(2)gas separation applications.Therefore,this review can provide researchers with light horizons in using the high potential of Mg-based materials as efficient fillers in MMMs to achieve excellent permeability and selectivity and generally improve their performance in CO_(2)gas separation applications.
基金supported by the National Natural Science Foundation of China(Nos.22205207 and 22378369)major project of NSF of Zhejiang Province(LD24B060001).
文摘Due to the similar physicochemical properties of acetylene(C_(2)H_(2))and carbon dioxide(CO_(2)),separating C_(2)H_(2)from a CO_(2)/C_(2)H_(2)mixture poses a significant challenge in the petrochemical industry.Herein,we successfully synthesized a novel SiF_(6)^(2) anion pillared cage metal-organic framework ZNU-15 possessing a new crs topological structure for the selective capture of C_(2)H_(2).As a linear bidentate linker,the fluorinated SiF_(6)^(2) anion partitions the pores into various sized cages.ZNU-15 displays moderate adsorption for C_(2)H_(2)with a capacity of 36.0 cm^(3)g^(-1)at 298 K and 1 bar,which is 2.7 times higher than the CO_(2)uptake.The IAST selectivity of C_(2)H_(2)/CO_(2)for ZNU-15 at 298 K and 100 kPa is 10.5,surpassing that of most reported materials.The Qst values for C_(2)H_(2)and CO_(2)at zero coverage are 54.0 and 42.8 kJ mol^(-1),respectively.Moreover,breakthrough experimental tests show that ZNU-15 is capable of effectively separating C_(2)H_(2)from a C_(2)H_(2)/CO_(2)mixture.Theoretical calculations further indicate that C_(2)H_(2)is preferentially trapped by the small cage with four cooperative hydrogen bonds.
基金financially supported by the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(XDA0390000)open research fund of State Key Laboratory of Mesoscience and Engineering(MESO-23-D11).
文摘The production of high-purity H_(2) is the building block of hydrogen economy,which can greatly promote the construction of related technologies and infrastructure.Efficient H_(2)/CH_(4) separation is a necessary unit in producing high-purity energy and reducing greenhouse gas emissions,which can meet the industrial demand and help to address the energy issue and achieve global carbon neutrality goals.Membrane separation technology,as a promising strategy for H_(2) purification,has attracted much attention due to its high efficiency,energy conservation and versatile applications.This article reviews the latest research advances in the high-performance membranes for H_(2)/CH_(4) separation,and elu-cidates the effect of membrane materials,preparation methods and membrane structure on separation performance from the perspective of separation mechanisms.It also summarized the essential aspects of membrane design,such as microstructural regulation,multiphase coupling,the optimal usage conditions and simple analysis of economic benefits.Finally,the current challenges and future directions of membranes for H_(2)/CH_(4) separation were discussed,intending to provide in-depth reference and inspiration for the theoretical research and practical application of membrane separation technology.
基金financially supported by the National Natural Science Foundation of China(Nos.21975044,21971038,21922810 and 22271046)the Fujian Provincial Department of Science and Technology(Nos.2023J01355,2023J011106 and 2022R1022001).
文摘Achieving efficient adsorption and separation of C_(2)H_(2)/CO_(2)mixtures is a goal that people have always pursued to improve the situation of high energy consumption brought by traditional separation technologies in industry today.High-nuclearity metal cluster-based MOFs with different functionalities are promising for this separation,but it is a complicated and difficult task to precisely control their structures.The strategy of pore-space partition(PSP)is a powerful way to construct this type MOFs,which has the characteristic of isostructural relationship,and can be resulted in a similar performance for them.Therefore,it is an interesting work to explore the effect of MOFs property by adjusting the size of PSP dividers.Herein,three tetranuclear Cu(Ⅱ)cluster-based MOFs(FJU-112/113/114)with dual functionalities has been successfully obtained by PSP strategy with various lengths of divider units.With the highest microporosity and unique functional site,FJU-114 realized a good improvement in the adsorption and separation performance of C_(2)H_(2)/CO_(2).The gas adsorption and lab-scale C_(2)H_(2)/CO_(2)breakthrough experiments demonstrated that FJU-114 exhibits the highest adsorption uptake of 77 cm^(3)/g for C_(2)H_(2),and shows the best separation factor of 4.2 among three MOFs.The GCMC simulation reveals that a stronger adsorption binding site of C_(2)H_(2)in FJU-114a located in the cage II near the unchanged tetranuclear copper node,combined with its high microporosity to achieve the effect of dual functionalities for the improvement performance of C_(2)H_(2)adsorption and separation.
基金supported by the Fundamental Research Program of Shanxi Province(Nos.20210302124003 and 20210302124015)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(No.2021L032)+2 种基金the National Natural Science Foundation of China(No.52103307)China Postdoctoral Science Foundation(No.2023M742575)the General Program of Shanxi Province(No.202203021211150).
文摘Zeolitic imidazole frameworks(ZIFs)are a class of three-dimensional(3D)skeletalmaterials with zeolitic topology composed of metal ions and imidazolium ligands,which combine the advantages of zeolites and metal-organic frameworks.ZIFs are widely used for adsorption of carbon dioxide(CO_(2))from flue gas due to its excellent hydrophobicity,chemical stability,thermal stability and gas adsorption properties.This study focuses on the effects of structures of ZIFs on CO_(2)capture and separation from the viewpoints of topologies,pore channels,ligand functional groups and composite structures.On this basis,the mechanisms of CO_(2)adsorption and selective separation are reviewed,as well as the challenges such as hydrophobicity,thermal and chemical stability faced by ZIFs in practical applications.
基金supported by the National Natural Science Foundation of China(22478007)the National Key Research and Development Program of China(2022YFB3805100)the Anhui Provincial Natural Science Foundation(2023AH050728)。
文摘One of the main challenges in oil-water separation of traditional Chinese medicines(TCM)is to obtain essential oils from the aromatic water of TCM.In this study,silicon dioxide/polyvinylidene fluoride(SiO_(2)/PVDF)membranes were prepared using nonsolvent induce phase separation.Then polydimethylsiloxane(PDMS)was coated to obtain PDMS/SiO_(2/)PVDF membranes.Separated essential oils and water from aromatic water in the gaseous state by vapor permeation membrane separation technology.The relationship between membrane structure and membrane separation effect was investigated.Response surface methodology was used to develop a quadratic model for the separation factor,membrane permeation separation index and membrane preparation process.The optimal process parameters for the membrane separation were 12.31%(mass)concentration of PVDF solution,9.6%(mass)of N,Ndimethylacetamide in the solidification bath,and 0.2 g hydrophobic nano-SiO_(2)incorporation,with a separation factor of 14.45,and a membrane flux of 1203.04 g·m^(-2)·h^(-1).Compared with the PDMS/PVDF membranes,the separation factor and membrane flux were increased by 68.59%and 3.46%,respectively.Compared with the SiO_(2)/PVDF membranes,the separation factor and membrane flux were increased by478%and 79.33%,respectively.Effectively mitigated the limitations of traditional polymer membrane material performance affected by the"trade-off"effect.Attenuated total internal reflection-Fourier transform infrared spectroscopy,contact angle,scanning electron microscopy and energy dispersive spectroscopy were used to characterize the PDMS/SiO_(2)/PVDF membranes,and gas chromatography was used to characterize the permeate.In addition,the contents of L-menthol,L-menthone,menthyl acetate and limonene in the permeate,conformed to the European Pharmacopoeia standards.This study provided an effective preparation strategy of a feasible hydrophobic powder polymer membrane for the separation of essential oils from gaseous peppermint aromatic water.
基金Project(52204363)supported by the National Natural Science Foundation of ChinaProject(2024JJ8042)supported by the Hunan Natural Science Foundation,ChinaProject(22C0220)supported by the Education Department of Hunan Province,China。
文摘The lime-Cu^(2+)-xanthate process is commonly used for the flotation separation of sphalerite from pyrite.In this process,lime is added to the pulp to inhibit the floatability of pyrite.However,the excessive use of lime can result in pipeline blockage and inadequate recovery of associated precious metals.Therefore,it is necessary to develop new flotation process that minimizes or eliminates the use of lime.In this paper,a novel Fe^(3+)-Cu^(2+)-butyl xanthate process was developed as an alternative to lime for separating of sphalerite from pyrite.The flotation results indicated that with the artificially-mixed minerals,the flotation recovery of pyrite was lower than 16%and that of sphalerite was higher than 47%at pH 5.0−10.0.The zeta potential measurements revealed that ferric ion preferred to adsorb on pyrite,and copper ion displaced with zinc ion from the lattice at the interface of sphalerite.The wettability analyses indicated that the hydrophobicity of sphalerite surface increased apparently after being treated with Fe^(3+)-Cu^(2+)-BX,while the hydrophobicity of pyrite surface remained nearly unchanged.With XPS analysis,Cu-S bond and hydrophilic ferric hydroxide were detected separately on the surface of sphalerite and pyrite after conditioning with Fe^(3+)-Cu^(2+)-BX,which facilitated the flotation separation of sphalerite from pyrite with butyl xanthate collector.
基金Babol Noshirvani University of Technology for financially support of this project(BNUT/393054/2023)。
文摘In this study,Pebax■2533 polymer was used as the continuous phase and UiO-67 was employed as the filler to prepare mixed matrix membranes.UiO-67 is usually synthesized using two ligands:biphenyl-4,4'-dicarboxylate(bpdc)and 2,2'-bipyridine-5,5'-dicarboxylic acid(bpy).In this research,UiO-67 was synthesized not only with these two ligands but also using a mixed ligand approach(50% bpdc and 50% bpy).The synthesized UiOs were incorporated into the polymer matrix at mass percentages ranging from 0% to 2% to form the mixed matrix membranes(MMMs).Membranes containing UiO-67 with mixed ligands exhibited a greater affinity for CO_(2) compared to other membranes.Various analytical techniques,including X-ray diffraction,thermogravimetric analyzer,Fourier transform infrared spectroscope(FTIR),field emission scanning electron micro scope(FESEM),and differential scanning calorimetry,were used to analyze the properties of the prepared membranes.The FTIR spectrum confirmed all desired bands of Pebax?2533 and UiO-67 in the MMMs.The FESEM images showed that the pure Pebax membrane has a uniform structure,and the developed membranes are uniformly incorporated with the synthesized UiO-67 nanoparticles.Gas permeation measurements indicated that CO_(2) permeability and CO_(2)/CH_4 selectivity increased from 402.7 Barrer(1 Barrer=1.33×10^(-14)m^(3)(STP)·m·m^(-2)·s^(-1)·kPa^(-1))and 9.32 for the pure Pebax membrane at 1.0 MPa to 770.1 Barrer and 16.96 in the modified membrane.Additionally,the gas permeation test results demonstrated that adding functionalized porous nanofillers increases the CO_(2)separation performance.Permeability tests at different temperatures revealed that as temperature was raised,at constant pressure,CO_(2) permeability for the membrane containing the mixed ligand increased from 682.2 Barrer to 733.5 Barrer,While CO_(2)/CH_(4) selectivity decreased from 15.46 to 13.43.
基金The authors sincerely appreciate funding from“Producing Hydrogen in Trentino-H2@TN”(PAT-Trento)through the research grant(SAP 40104237)Researchers Supporting Project number(RSP2025R399)King Saud University,Riyadh,Saudi Arabia.
文摘Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is particularly significant in challenging coupled systems,such as CO_(2)photoreduction integrated with selective oxidation of toluene to benzaldehyde.However,developing such a system is quite challenging and often requires a precise design and engineering.Herein,we demonstrate a unique Ni-CdS@Ni(OH)_(2)heterojunction synthesized via an in-situ self-assembly method.Comprehensive mechanistic and theoretical investigations reveal that the NiCdS@Ni(OH)_(2)heterojunction induces dual electric fields(EFs):an intrinsic polarized electric-field within the CdS lattice from Ni doping and an interfacial electric-field from the growth of ultrathin nanosheets of Ni(OH)_(2)on NiCdS nanorods,enabling efficient spatial charge separation and enhanced redox potential.As proof of concept,the Ni-CdS@Ni(OH)_(2)heterojunction simultaneously exhibits outstanding bifunctional photocatalytic performance,producing CO at a rate of 427μmol g^(-1)h^(-1)and selectively oxidizing toluene to benzaldehyde at a rate of 1476μmol g^(-1)h^(-1)with a selectivity exceeding 85%.This work offers a promising strategy to optimize the utilization of photogenerated carriers in heterojunction photocatalysts,advancing synergistic photocatalytic redox systems.
基金supported by the National Natural Science Foundation of China(No.22271022,No 22378327).
文摘Covalent organic skeletons(COFs)have been widely used in gas separation due to their excellent pore structure,high crystallinity,and high specific surface area.In this work,Dha Tab-COF was synthesized by solvothermal method and filled in polyether block polyamide(PEBAX)to form mixed matrix membranes(MMMs).Various characterization methods such as Fourier transform infrared spectroscopy(FT-IR),Xray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM)and X-ray diffractometry(XRD)were used to characterize the structure of Dha Tab-COF as well as the MMMs.The effects of operating pressure,operating temperature and the content of Dha Tab-COF particles on the CO_(2)/CH_(4)separation performance of the membranes were investigated.The best separation performance with a CO_(2)permeability of 295.8 barrer(1 barrer=7.52×10^(-18)m^(3)·(STP)·m^(-2)·m·s^(-1)·Pa^(-1))and a CO_(2)/CH_(4)selectivity of 21.6 was achieved when the Dha Tab-COF content is 2%(mass),which were 45.7%and 108.1%higher than that of the pure PEBAX membrane,respectively.
基金financial support by the National Natural Science Foundation of China(NSFC,Grant No.22379153 and 22109128)the Ningbo Key Research and Development Project(2023Z147)the Ningbo 3315 Program。
文摘CuBi_(2)O_(4)(CBO)photocathodes hold significant promise for efficient photoelectrochemical(PEC)water splitting due to their favorable band gap and theoretical onset potential.However,their practical application is hindered by poor charge separation efficiency.Herein,we introduce a characteristic in-situ solution Fe-doping strategy that markedly improves photoelectrochemical performance of CBO,doubling the photocurrent density and achieving an unprecedented 190 mV anodic shift in the onset potential.By integrating with an electrochemical oxidation post-treatment,a record incident photon-to-current efficiency(IPCE)exceeding 40% at 0.6 V vs.RHE under visible light illumination is achieved.The versatility of the doping strategy is demonstrated across CBO photocathodes synthesized by different methods with various morphologies,grain sizes,and crystallinities.Mechanistic studies reveal that the gradient distribution of Fe^(3+)ions generates an internal electric field that facilitates efficient charge separation and increases acceptor density.The strong Fe-O bonding also enhances structural stability against photoinduced corrosion.Notably,our investigation uncovers the non-temperature-dependent nature of CBO photocurrent,indicating that PEC performance enhancement primarily depends on reducing carrier recombination rather than improving bulk conductivity.This work lays the groundwork for future advancements in water splitting performance of CBO photocathodes,offering a complementary strategy to conventional methods for enhancing charge separation efficiency.
基金supported by the National Science and Technology Planning Project(No.2011BAC08B00)the National High Technology Research and Development Program of China(863 Program)(No.2012AA03A611)
文摘In this paper, poly（amide-6-b-ethylene oxide） （Pebax1657）/SAPO-34 mixed matrix membranes （MMMs） were prepared by solvent-evaporation method with acetic acid as a novel solvent. CO2, N2, CH4 and H2 permeation properties were investigated, and the physical properties of Pebax/SAPO-34 MMMs were characterized by XRD and SEM. At low SAPO-34 content, it was homogeneously distributed in the Pebax ma- trix, and then precipitated and agglomerated at high SAPO-34 content. The crystallinity of Pebax phase in Pebax/SAPO-34 MMMs decreased initially and then rebounded as a result of phase separation. With the increase of transmembrane pressure difference, CO2 permeability was en- hanced due to the effect of pressure-induced plasticization. Owing to the happening of stratification, the CO2 permeability of Pebax/SAPO-34 MMMs （50 wt% SAPO-34） increased to 338 Barrer from 111 Barrer of pristine Pebax, while the selectivities of CO2/CH4 and CO2/N2 were almost unchanged. Compared with the pristine Pebax, the gas separation performances of Pebax/SAPO-34 MMMs were remarkably enhanced.
基金Supported by the National Key R&D Program of China(No.2017YFB0603400)the National Natural Science Foundation of China(No.21436009)Tianjin Research Program of Basic Research and Frontier Technology(No.15JCQNJC43400)
文摘Membrane separation technology has popularized rapidly and attracts much interest in gas industry as a promising sort of newly chemical separation unit operation. In this paper, recent advances on membrane processes for CO_2 separation are reviewed. The researches indicate that the optimization of operating process designs could improve the separation performance, reduce the energy consumption and decrease the cost of membrane separation systems. With the improvement of membrane materials recently,membrane processes are beginning to be competitive enough for CO_2 separation, especially for postcombustion CO_2 capture, biogas upgrading and natural gas carbon dioxide removal, compared with the traditional separation methods. We summarize the needs and most promising research directions for membrane processes for CO_2 separation in current and future membrane applications. As the time goes by, novel membrane materials developed according to the requirement proposed by process optimization with increased selectivity and/or permeance will accelerate the industrialization of membrane process in the near future. Based on the data collected in a pilot scale test, more effort could be made on the optimization of membrane separation processes. This work would open up a new horizon for CO_2 separation/Capture on Carbon Capture Utilization and Storage(CCUS).
文摘In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane and nanocomposite membranes were prepared via solution casting and solution blending methods, respectively. The fabricated membranes were characterized by field emission scanning electron microscopy（FESEM） to survey cross-sectional morphologies and thermal gravimetric analysis（TGA）to study thermal stability. Fourier transform infrared（FT-IR） and X-ray diffraction（XRD） analyses were also employed to identify variations of the chemical bonds and crystal structure of the membranes, respectively. Permeation of pure gases, CO, CHand Nthrough the prepared neat and nanocomposite membranes was studied at pressures of 3–18 bar and temperature of 25 °C. The obtained results showed that the fabricated nanocomposite membranes exhibit better separation performance compared to the neat PEBAX membrane in terms of both permeability and selectivity. As an example, at temperature of 25 °C and pressure of 3 bar, COpermeability, ideal CO/CHand CO/Nselectivity values for the neat PEBAX membrane are 110.67 Barrer, 11.09 and 50.08, respectively, while those values are 152.27 Barrer,13.52 and 62.15 for PEBAX/ZnO nanocomposite membrane containing 8 wt% ZnO.
基金supported by the National Natural Science Foundation of China (40673043 and 20576073)the Program for New Century Excellent Talents in University of Ministry of Education of China (NCET-06-0088)
文摘Ionic liquids （ILs） have been regarded as the potential novel solvents for improved analytical- and process-scale separation methods.The development of methods for the recovery of ILs from aqueous solutions to escape contamination and recycle samples will ultimately govern the viability of ILs in the future industrial applications. Therefore, in this paper a new method for separation of ILs from their dilute aqueous solutions and simultaneously purification of water was proposed on the basis of the CO2 hydrate formation. For illustration, the dilute aqueous solutions with concentrations of ILs ranging from 2× 10^-3 mol% to 2×10^-1 mol% were concentrated. The results show that the separation efficiency is very impressive and that the new method is applicable to aqueous solutions of both hydrophobic and hydrophilic ILs. Compared to the literature separation method based on the supercritical CO2, the new method is applicable to lower concentrations, and more importantly, its operation condition is mild.
基金support of the National Natural Science Foundation of China(No.0831002)Major International (Regional) Joint Research Project(No.21120102034)
文摘Novel porous aromatic frameworks（PAF-53 and PAF-54） have been obtained by the polymerization of amino compound（p-phenylenediamine and melamine） and cyanuric chloride. They display a certain amount of CO2 adsorption capacity and highly selective separation of CO2/CH4 and CO2/N2 as 18.1 and83 by Henry Law respectively. They may be applied as ideal adsorbents to separate and capture CO2.
基金The National High Technology Research and Development Program of China(863 Program)(No.2012AA051801)the National Natural Science Foundation of China(No.51176033)
文摘The process of an O2//CO2 power plant based on chemical looping air separation （CLAS） is modeled using the Aspen Plus software. The operating parameters and power consumption of the CLAS unit are analyzed. The CLAS system, thermal power generation system and flue gas cooling and compression unit （CCU） are coupled and optimized, and the temperature and flow of the flue gas extraction are determined. The results indicate that the net plant efficiency of CLAS O2/CO2 power plant is 39.2%, which is only 3.54% lower than that of the conventional power plants without carbon capture. However, the O2/CO2 power plant based on cryogenic air separation technology brings 8% to 10% decrease in the net plant efficiency. By optimizations, the net plant efficiency increases by 1.65%. The energy consumption of the CCU accounts for 59.7% and the pump accounts for 27.1%. The oxygen concentration from the chemical looping air separation unit is 12.2%.
基金the China University of Petroleum Foundationthe Research Institute of Safety and Environment TechnologyChina National Petroleum Corporation
文摘This study aims at determining the optimal CO2 separation technology for Chinese refineries, based on current available technologies, by the method of comprehensive evaluation. Firstly, according to the characteristics of flue gas from Chinese refineries, three feasible CO2 separation technologies are selected. These are pressure swing adsorption （PSA）, chemical absorption （CA）, and membrane absorption （MA）. Secondly, an economic assessment of these three techniques is carried out in accordance with cash flow analysis. The results show that these three techniques all have economic feasibility and the PSA technique is the best. Finally, to further optimize the three techniques, a two-level fuzzy comprehensive evaluation model is established, including economic, technological, and environmental factors. Considering all the factors, PSA is optimal for Chinese refineries, followed by CA and MA. Therefore, to reduce Chinese refineries carbon emission, it is suggested that CO2 should be captured from off-gases using PSA.
