Mixed matrix membrane used to selective removal of CO2 was considered as an efficient solution to energy and environmental sustainability. In this study, a MMM that consists of amide functionalized porous coordination...Mixed matrix membrane used to selective removal of CO2 was considered as an efficient solution to energy and environmental sustainability. In this study, a MMM that consists of amide functionalized porous coordination polymer filler（MIL-53-NH2） was successfully prepared, which sharply promotes the CO2/N2 selectivity from 44（neat polymeric membrane） to 75. Remarkably, the positive effect of amide group and nanochannel of MIL-53-NH2 filler was illustrated by decreased selectivity of the MMM with formic acid modified MIL-53-NH2 filler（MIL-53-NHCOH）.展开更多
Samples of methane molecules grade diameter channel CHA-type molecular sieves(Chabazite-K, SAPO-34 and SSZ-13) were investigated using the adsorption separation of CH4/N2 mixtures. The isotherms recorded for CH4 and N...Samples of methane molecules grade diameter channel CHA-type molecular sieves(Chabazite-K, SAPO-34 and SSZ-13) were investigated using the adsorption separation of CH4/N2 mixtures. The isotherms recorded for CH4 and N2 follow a typical type-Ι behavior, which were fitted well with the Sips model(R2>0.999) and the selectivity was calculated using IAST theory. The results reveal that Chabazite-K has the highest selectivity(SCH4/N= 5.5).2 SSZ-13 has the largest capacity, which can adsorb up to a maximum of 30.957 cm3·g-1(STP) of CH4, due to it having the largest pore volume and surface area, but the lowest selectivity(SCH4/N2= 2.5). From the breakthrough test, we can conclude that SSZ-13 may be a suitable candidate for the recovery of CH4 from low concentration methane(CH4<20%) based on its larger pore volume and higher CH4 capacity. Chabazite-K is more suited to the separation of high concentration methane(CH4>50%) due to its higher selectivity.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
In order to investigate the effect of the La2O3 on the phase separation and crystallization of ZnO-B2O3-SiO2 glass, after the occurence of the phase separation and crystallization of glasses by heat treatment, the mic...In order to investigate the effect of the La2O3 on the phase separation and crystallization of ZnO-B2O3-SiO2 glass, after the occurence of the phase separation and crystallization of glasses by heat treatment, the microstructure morphology and distribution of elements in different sample areas were characterized by the scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS);the non-isothermal crystallization kinetics of the glass samples was studied by using a differential scanning calorimeter(DSC) and the precipitated crystals of crystallized glass were determined by the X-ray diffraction(XRD). The results suggest that the phase separation and crystallization of 60ZnO-30 B2O3-10SiO2 glass occur at glass surface, and the incorporation of small amount(<4 mol%) of La2O3 significantly inhibits the glass phase separation and consequently improves the thermal stability of glass.Doping of La2O3 accelerates the glass crystallization at the elevated temperature(660 ℃), making the depth of crystal layer thicker and diffraction intensity in XRD patterns stronger. However, due to the precipitation of several crystals that occur simultaneously when La2O3 doping amount is 4 mol%, crystallization of the 60ZnO-30B2O3-10SiO2 glass is obviously depressed, the crystallization activation energy Ec and the relative crystallinity Xc of the glass reach the maximum and the minimum values, respectively.Although transition from one-dimensional growth of crystals to two-dimensional growth of crystals results from La2O3 addition, the one-dimensional growth of crystals remains dominant in crystallization process. This work can provide some useful information for preparing glass ceramics with nano-crystals precipitated in the glass surface.展开更多
The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][...The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][Pro]/polyethylene glycol 200(PEG200) mixtures were selected to prepare novel SILMs because of their green and costeffective characterization, and the CO_2/N_2 separation with the prepared SILMs was investigated experimentally at temperatures from 308.15 to 343.15 K. The temperature effect on the permeability, solubility and diffusivity of CO_2 was modeled with the Arrhenius equation. A competitive performance of the prepared SILMs was observed with high CO_2 permeability ranged in 343.3–1798.6 barrer and high CO_2/N_2 selectivity from 7.9 to 34.8.It was also found that the CO_2 permeability increased 3 times by decreasing the viscosity of liquids from 370 to38 m Pa·s. In addition, the inherent mechanism behind the significant permeability enhancement was revealed based on the diffusion-reaction theory, i.e. with the addition of PEG200, the overall resistance was substantially decreased and the SILMs process was switched from diffusion-control to reaction-control.展开更多
The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction ...The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction within 6 h using AlCl 3 as complex former. The rare earth chlorides were more readily transported and concentrated in the middle temperature range of 980～1100 K and the transport efficiency was in the order of Sm≈Gd>Eu. The separation factor, expressed as molar ratio for the resulting chlorides, was 1 70 for Eu∶Sm, 1 88 for Eu∶Gd, 1 24 for Sm∶Gd in the higher temperature region, and 2 76 for Sm∶Eu, 2 83 for Gd∶Eu and 1 12 for Gd∶Sm in the lower temperature region, respectively. All results are much higher than those of the conventional wet process.展开更多
Developing high activity and low-cost materials to produce hydrogen by the sustainable way of photoelectrochemical is key to social development.The abundance and inexpensive Cu_(2)O has been received increasing resear...Developing high activity and low-cost materials to produce hydrogen by the sustainable way of photoelectrochemical is key to social development.The abundance and inexpensive Cu_(2)O has been received increasing research as its suitable energy level for photocatalytic water reduction.However,the fast charge recombination rate and the sluggish catalytic kinetics are the huge challenges facing the Cu_(2)O photoreduction.Here,the highly reactive Cu_(2)O@C-MoS_(2)photocathode is constructed by depositing dual-cocatalysts of the carbon layer and MoS_(2)nanosheets on Cu_(2)O nanowires to realize efficient water reduction.An impressive carrier concentration of 6.59×10^(23)cm^(-3)is received,which is 2.78 times of the bare Cu_(2)O,resulting in remarkable enhancement in photocurrent density of 3.34 times for the Cu_(2)O@CMoS_(2)photocathode.Moreover,the applied bias photon-to-current conversion efficiency of the bare Cu_(2)O enhanced 4.5 times from 0.16%to 0.72%in the Cu_(2)O@C-MoS_(2)photocathode.The analysis shows that the Cu_(2)O as light absorber,the carbon layer as electron transfer promoter,and MoS_(2)nanosheets as catalytic sites,thus facilitating chrage separation and enhancing catalytic kinetics.This system paves a feasible strategy for designing other photoelectrodes to realize efficient charge separation and high catalytic activity.展开更多
This research investigates the permeability of CO2 and N2 as well as selectivity of CO2 over N2 of polysulfone (PSF) mixed matrix membranes filled with zeolite 4Å particles. The membranes were prepared by sol...This research investigates the permeability of CO2 and N2 as well as selectivity of CO2 over N2 of polysulfone (PSF) mixed matrix membranes filled with zeolite 4Å particles. The membranes were prepared by solution-casting method and utilized to determine the permeation rates of N2 and CO2. It was characterized by FTIR and the gas separation performance was analysed by Design of Expert (DOE) method. FTIR result revealed the intensity of peak for sulfone S=O vibration at 1322 cm-1;it was related to O=S=O bound of polysulfone in the sample. The single concentration variable has low outcome, however the mixture concentration interaction was effectively to lead better selectivity of CO2 over N2. In terms of interaction between mixture concentrations, interaction between PSF and N-Methyl-2-pyrrolidone (NMP) has considerable effect on the permeability of CO2 with the highest F value of 0.46 membrane. NMP exhibited a high degree of polarity and hydrogen bonding which led to effect of selective skin and permeation rate. The model regression equations were developed as the potential use for screening the permeability of CO2 and N2 based on the deviation effect of polymer concentration.展开更多
An efficient route for the synthesis of 5-substituted 1H-tetrazole via[2＋3]cycloaddition of nitriles and sodium azide is reported usingγ-Fe2O3 nanoparticles as a magnetic separable catalyst.Under optimized condition...An efficient route for the synthesis of 5-substituted 1H-tetrazole via[2＋3]cycloaddition of nitriles and sodium azide is reported usingγ-Fe2O3 nanoparticles as a magnetic separable catalyst.Under optimized conditions,the moderate to good yields（71-95%） can be obtained.The catalyst can be easily separated by a magnet and reused for several circles.展开更多
基金financial support of the National Natural Science Foundation of China (No. 21671102)Natural Science Foundation of Jiangsu Province (No. BK20161538)+2 种基金Innovative Research Team Program by the Ministry of Education of China (No. IRT17R54)Six Talent Peaks Project in Jiangsu Province (No. JY-030)State Key Laboratory of Materials-Oriented Chemical Engineering (No. ZK201406)
文摘Mixed matrix membrane used to selective removal of CO2 was considered as an efficient solution to energy and environmental sustainability. In this study, a MMM that consists of amide functionalized porous coordination polymer filler（MIL-53-NH2） was successfully prepared, which sharply promotes the CO2/N2 selectivity from 44（neat polymeric membrane） to 75. Remarkably, the positive effect of amide group and nanochannel of MIL-53-NH2 filler was illustrated by decreased selectivity of the MMM with formic acid modified MIL-53-NH2 filler（MIL-53-NHCOH）.
基金financial support from the National Natural Science Foundation of China (Nos. 51672186, 21676175)
文摘Samples of methane molecules grade diameter channel CHA-type molecular sieves(Chabazite-K, SAPO-34 and SSZ-13) were investigated using the adsorption separation of CH4/N2 mixtures. The isotherms recorded for CH4 and N2 follow a typical type-Ι behavior, which were fitted well with the Sips model(R2>0.999) and the selectivity was calculated using IAST theory. The results reveal that Chabazite-K has the highest selectivity(SCH4/N= 5.5).2 SSZ-13 has the largest capacity, which can adsorb up to a maximum of 30.957 cm3·g-1(STP) of CH4, due to it having the largest pore volume and surface area, but the lowest selectivity(SCH4/N2= 2.5). From the breakthrough test, we can conclude that SSZ-13 may be a suitable candidate for the recovery of CH4 from low concentration methane(CH4<20%) based on its larger pore volume and higher CH4 capacity. Chabazite-K is more suited to the separation of high concentration methane(CH4>50%) due to its higher selectivity.
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Project supported by National Natural Science Foundation of China(51662033,51362019)Natural Science Foundation of the Inner Mongolia Autonomous Region(2016JQ05)
文摘In order to investigate the effect of the La2O3 on the phase separation and crystallization of ZnO-B2O3-SiO2 glass, after the occurence of the phase separation and crystallization of glasses by heat treatment, the microstructure morphology and distribution of elements in different sample areas were characterized by the scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS);the non-isothermal crystallization kinetics of the glass samples was studied by using a differential scanning calorimeter(DSC) and the precipitated crystals of crystallized glass were determined by the X-ray diffraction(XRD). The results suggest that the phase separation and crystallization of 60ZnO-30 B2O3-10SiO2 glass occur at glass surface, and the incorporation of small amount(<4 mol%) of La2O3 significantly inhibits the glass phase separation and consequently improves the thermal stability of glass.Doping of La2O3 accelerates the glass crystallization at the elevated temperature(660 ℃), making the depth of crystal layer thicker and diffraction intensity in XRD patterns stronger. However, due to the precipitation of several crystals that occur simultaneously when La2O3 doping amount is 4 mol%, crystallization of the 60ZnO-30B2O3-10SiO2 glass is obviously depressed, the crystallization activation energy Ec and the relative crystallinity Xc of the glass reach the maximum and the minimum values, respectively.Although transition from one-dimensional growth of crystals to two-dimensional growth of crystals results from La2O3 addition, the one-dimensional growth of crystals remains dominant in crystallization process. This work can provide some useful information for preparing glass ceramics with nano-crystals precipitated in the glass surface.
基金Supported by the National Basic Research Program of China(2013CB733501)the National Natural Science Foundation of China(21136004,21176112,21476106,and21428601)+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education(No.20133221110001)the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][Pro]/polyethylene glycol 200(PEG200) mixtures were selected to prepare novel SILMs because of their green and costeffective characterization, and the CO_2/N_2 separation with the prepared SILMs was investigated experimentally at temperatures from 308.15 to 343.15 K. The temperature effect on the permeability, solubility and diffusivity of CO_2 was modeled with the Arrhenius equation. A competitive performance of the prepared SILMs was observed with high CO_2 permeability ranged in 343.3–1798.6 barrer and high CO_2/N_2 selectivity from 7.9 to 34.8.It was also found that the CO_2 permeability increased 3 times by decreasing the viscosity of liquids from 370 to38 m Pa·s. In addition, the inherent mechanism behind the significant permeability enhancement was revealed based on the diffusion-reaction theory, i.e. with the addition of PEG200, the overall resistance was substantially decreased and the SILMs process was switched from diffusion-control to reaction-control.
文摘The mutual separation characteristics were investigated for the neighboring Sm, Eu and Gd from their ternary oxide mixture Sm 2O 3 Eu 2O 3 Gd 2O 3 by a stepwise chlorination chemical vapor transport reaction within 6 h using AlCl 3 as complex former. The rare earth chlorides were more readily transported and concentrated in the middle temperature range of 980～1100 K and the transport efficiency was in the order of Sm≈Gd>Eu. The separation factor, expressed as molar ratio for the resulting chlorides, was 1 70 for Eu∶Sm, 1 88 for Eu∶Gd, 1 24 for Sm∶Gd in the higher temperature region, and 2 76 for Sm∶Eu, 2 83 for Gd∶Eu and 1 12 for Gd∶Sm in the lower temperature region, respectively. All results are much higher than those of the conventional wet process.
基金supported financially by the National Natural Science Foundation of China(Nos.51571151,51701139,51671143,and U1601216)the China Postdoctoral Science Foundation(2019M661014)the Tianjin Natural Science Foundation(No.16JCYBJC17600)。
文摘Developing high activity and low-cost materials to produce hydrogen by the sustainable way of photoelectrochemical is key to social development.The abundance and inexpensive Cu_(2)O has been received increasing research as its suitable energy level for photocatalytic water reduction.However,the fast charge recombination rate and the sluggish catalytic kinetics are the huge challenges facing the Cu_(2)O photoreduction.Here,the highly reactive Cu_(2)O@C-MoS_(2)photocathode is constructed by depositing dual-cocatalysts of the carbon layer and MoS_(2)nanosheets on Cu_(2)O nanowires to realize efficient water reduction.An impressive carrier concentration of 6.59×10^(23)cm^(-3)is received,which is 2.78 times of the bare Cu_(2)O,resulting in remarkable enhancement in photocurrent density of 3.34 times for the Cu_(2)O@CMoS_(2)photocathode.Moreover,the applied bias photon-to-current conversion efficiency of the bare Cu_(2)O enhanced 4.5 times from 0.16%to 0.72%in the Cu_(2)O@C-MoS_(2)photocathode.The analysis shows that the Cu_(2)O as light absorber,the carbon layer as electron transfer promoter,and MoS_(2)nanosheets as catalytic sites,thus facilitating chrage separation and enhancing catalytic kinetics.This system paves a feasible strategy for designing other photoelectrodes to realize efficient charge separation and high catalytic activity.
文摘This research investigates the permeability of CO2 and N2 as well as selectivity of CO2 over N2 of polysulfone (PSF) mixed matrix membranes filled with zeolite 4Å particles. The membranes were prepared by solution-casting method and utilized to determine the permeation rates of N2 and CO2. It was characterized by FTIR and the gas separation performance was analysed by Design of Expert (DOE) method. FTIR result revealed the intensity of peak for sulfone S=O vibration at 1322 cm-1;it was related to O=S=O bound of polysulfone in the sample. The single concentration variable has low outcome, however the mixture concentration interaction was effectively to lead better selectivity of CO2 over N2. In terms of interaction between mixture concentrations, interaction between PSF and N-Methyl-2-pyrrolidone (NMP) has considerable effect on the permeability of CO2 with the highest F value of 0.46 membrane. NMP exhibited a high degree of polarity and hydrogen bonding which led to effect of selective skin and permeation rate. The model regression equations were developed as the potential use for screening the permeability of CO2 and N2 based on the deviation effect of polymer concentration.
基金the Jiangsu Province Foundation of Natural Science(No.BK2009678) for the financial support
文摘An efficient route for the synthesis of 5-substituted 1H-tetrazole via[2＋3]cycloaddition of nitriles and sodium azide is reported usingγ-Fe2O3 nanoparticles as a magnetic separable catalyst.Under optimized conditions,the moderate to good yields（71-95%） can be obtained.The catalyst can be easily separated by a magnet and reused for several circles.
