Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into pol...Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into polyethersulfone(PES)membranes fabricated by none-solvent induced phase separation.Then,polydopamine(PDA)coating on the surface of prepared membrane was carried out at pH 8.5.The morphology and structure,surface hydrophilicity,permeation flux,BSA rejection,antifouling and stability performances of PES and PDA/PES modified membranes were investigated in detail.The results indicated that PDA was successfully attached onto the membranes.Membrane hydrophilicity was evaluated by water contact angle measurement.The contact angles of modified membranes reduced remarkably,suggesting that the membrane hydrophilicities were significantly increased.The results of filtration tests,which were done by dead-end filtration of bovine serum albumin solution,showed that the properties of permeability and fouling resistance were obviously improved by PDA modification.When polyvinylpyrrolidone mass content reached 10%,flux recovery ratio of modified membrane was up to91.23%,and its BSA rejection were over 70%.The results of stability tests showed that the modified membranes had good mechanical stability and chemical stability.This facile fabrication procedure and outstanding performances suggested that the modified membranes had a potential in treating fouling.展开更多
A highly efficient and stable hydrotalcite-derived Cu-MgAlO catalyst was developed for the partial oxidation of cyclohexane with molecular oxygen.The physical–chemical properties of Cu-MgAlO catalysts were studied,an...A highly efficient and stable hydrotalcite-derived Cu-MgAlO catalyst was developed for the partial oxidation of cyclohexane with molecular oxygen.The physical–chemical properties of Cu-MgAlO catalysts were studied,and the results indicated that the copper component had been successfully introduced into the hydrotalcite unit layer structure.The catalytic reaction results showed that copper as the active species could activate CAH bond and effectively promote the decomposition of cyclohexyl hydroperoxide(CHHP)to the mixture of cyclohexanol and cyclohexanone(KA oil).8.3%of cyclohexane conversion and 82.9%of selectivity for KA oil were obtained over 9%Cu-MgAlO catalyst at 150℃with 0.6 MPa of oxygen pressure for 2 h.Especially,its catalytic performance was still stable after five runs.展开更多
The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation,poor reusability,and low efficiency.In this work,a facile strate...The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation,poor reusability,and low efficiency.In this work,a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts.Biological veins(Bio-veins)with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles.Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins,and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins(50–300 nm)was significantly smaller than Ag@AgCl obtained by the co-precipitation method(1–3μm).The Bio-veins played a vital role in the photocatalysis reaction system.The degradation efficiency of the Ag@AgCl/Bio-veins(CI4)was up to 3.50 times as high as pure Ag@AgCl.Furthermore,the composites also exhibited excellent recyclability and stability under both visible and solar light.This work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.展开更多
A stable and recyclable of BiOBr/silk fibroincellulose acetate composite film was prepared by blendingwet phase transformation and in situ precipitate technology.The cellulose acetate film modified by silk fibroin for...A stable and recyclable of BiOBr/silk fibroincellulose acetate composite film was prepared by blendingwet phase transformation and in situ precipitate technology.The cellulose acetate film modified by silk fibroin formed a finger-shaped porous structure,which provided a large space for the uniform growth of BiOBr nanosheets and facilitated the shuttle flow of dyes in film.The morphology,phase structure,and optical properties of the composite films were characterized using various techniques,and their photocatalytic performance for dye wastewater was evaluated under visible light irradiation.Results showed that the BiOBr/SF-CA composite film exhibited efficient photocatalytic activity with 99.9%of rhodamine B degradation rate.Moreover,the composite film maintained high catalytic stability because Bi as the active species deposited on the film showed almost no loss.Finally,the possible photocatalytic mechanisms in the BiOBr/SF-CA composite film were speculated through radical-trapping experiments and electron spin resonance testing.展开更多
In this work,a new mesoporous silicon sulfonic acid catalyst derived from silicic acid has been successfully prepared by the chemical bonding method.The physicochemical properties of mesoporous silicon sulfonic acid c...In this work,a new mesoporous silicon sulfonic acid catalyst derived from silicic acid has been successfully prepared by the chemical bonding method.The physicochemical properties of mesoporous silicon sulfonic acid catalysts have been systematically characterized using various techniques.The results demonstrate that sulfonic acid groups have been grafted on silicic acid by forming a new chemical bond(Si-O-S).The mesoporous silicon sulfonic acid exhibits excellent catalytic performance and stability in the vapor phase hydroamination reaction of cyclohexene with cyclohexylamine.Cyclohexene conversion of 61% and 97% selectivity to dicyclohexylamine was maintained after running the reaction for over 350 h at 280℃.The developed mesoporous silicon sulfonic acid catalyst shows advantages of low cost,superior acid site accessibility,and long term reactivity stability.Moreover,a possible catalytic hydroamination reaction mechanism over silicon sulfonic acid was suggested.It has been demonstrated that the sulfonic acid groups of the catalyst play an important role in the hydroamination.The present work provides a simple,efficient,and environmentally friendly method for the hydroamination of cyclohexene to valuable dicyclohexylamine,which also shows important industrial application prospects.展开更多
An ion-imprinted sorbent(IIP)was prepared by using Ni^2+ as template,3-[2(2-aminoethylamino)ethylamino]propyl-trimethoxysilane as functional monomer,and silica gel as carrier.The adsorption performance of IIP towards ...An ion-imprinted sorbent(IIP)was prepared by using Ni^2+ as template,3-[2(2-aminoethylamino)ethylamino]propyl-trimethoxysilane as functional monomer,and silica gel as carrier.The adsorption performance of IIP towards Ni^2+ was investigated.IIP showed a higher adsorption capacity than that of non-imprinted sorbent,and it also exhibited high selectivity for Ni^2+ in the presence of Cu^2+ and Zn^2+ ions.Then,IIP was used to form a dynamic membrane onto the surface of ceramic membrane for treatment of electroplating wastewater containing Ni^2+.Compared with ceramic membrane,IIP dynamic membrane had much higher steady membrane flux,and also rejected Ni^2+ to obtain a lower concentration of Ni2+ in the permeate fluid.Perhaps it is suitable for future practice applications.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51573041,21776067)the Demonstration Base Project of University-Enterprise Cooperation of Hunan Province(No.145812)。
文摘Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into polyethersulfone(PES)membranes fabricated by none-solvent induced phase separation.Then,polydopamine(PDA)coating on the surface of prepared membrane was carried out at pH 8.5.The morphology and structure,surface hydrophilicity,permeation flux,BSA rejection,antifouling and stability performances of PES and PDA/PES modified membranes were investigated in detail.The results indicated that PDA was successfully attached onto the membranes.Membrane hydrophilicity was evaluated by water contact angle measurement.The contact angles of modified membranes reduced remarkably,suggesting that the membrane hydrophilicities were significantly increased.The results of filtration tests,which were done by dead-end filtration of bovine serum albumin solution,showed that the properties of permeability and fouling resistance were obviously improved by PDA modification.When polyvinylpyrrolidone mass content reached 10%,flux recovery ratio of modified membrane was up to91.23%,and its BSA rejection were over 70%.The results of stability tests showed that the modified membranes had good mechanical stability and chemical stability.This facile fabrication procedure and outstanding performances suggested that the modified membranes had a potential in treating fouling.
基金the financial support by the National Natural Science Foundation of China (21676226 and 21776067)Natural Science Foundation for Distinguished Young Scholars in Hunan Province (2018JJ1023 and 2020JJ2014)+3 种基金Natural Science Foundation in Hunan Province (2018JJ3144)Key Research and Development Program in Hunan Province (2019GK2041)Scientific Research Fund of Hunan Provincial Education Department (17C0630)PhD Startup Foundation of Hunan University of Science and Technology (E51756)
文摘A highly efficient and stable hydrotalcite-derived Cu-MgAlO catalyst was developed for the partial oxidation of cyclohexane with molecular oxygen.The physical–chemical properties of Cu-MgAlO catalysts were studied,and the results indicated that the copper component had been successfully introduced into the hydrotalcite unit layer structure.The catalytic reaction results showed that copper as the active species could activate CAH bond and effectively promote the decomposition of cyclohexyl hydroperoxide(CHHP)to the mixture of cyclohexanol and cyclohexanone(KA oil).8.3%of cyclohexane conversion and 82.9%of selectivity for KA oil were obtained over 9%Cu-MgAlO catalyst at 150℃with 0.6 MPa of oxygen pressure for 2 h.Especially,its catalytic performance was still stable after five runs.
基金This work was supported by the National Natural Science Foundation of China(Grant No.21776067)the Outstanding Youth Foundation of Hunan Province(Grant No.2020JJ2014)+1 种基金the Natural Science Foundation of Hunan Province(Grant Nos.2022JJ30264,2020JJ5159)the Scientific Research Fund of Hunan Provincial Education Department(Grant Nos.20C0803,21B0476).
文摘The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation,poor reusability,and low efficiency.In this work,a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts.Biological veins(Bio-veins)with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles.Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins,and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins(50–300 nm)was significantly smaller than Ag@AgCl obtained by the co-precipitation method(1–3μm).The Bio-veins played a vital role in the photocatalysis reaction system.The degradation efficiency of the Ag@AgCl/Bio-veins(CI4)was up to 3.50 times as high as pure Ag@AgCl.Furthermore,the composites also exhibited excellent recyclability and stability under both visible and solar light.This work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.
基金the financial support by the National Natural Science Foundation of China(Grant No.22202068)Natural Science Foundation in Hunan Province(Grant No.2021JJ30239)Natural Science Foundation for Distinguished Young Scholars in Hunan Province(Grant No.2020JJ2014).
文摘A stable and recyclable of BiOBr/silk fibroincellulose acetate composite film was prepared by blendingwet phase transformation and in situ precipitate technology.The cellulose acetate film modified by silk fibroin formed a finger-shaped porous structure,which provided a large space for the uniform growth of BiOBr nanosheets and facilitated the shuttle flow of dyes in film.The morphology,phase structure,and optical properties of the composite films were characterized using various techniques,and their photocatalytic performance for dye wastewater was evaluated under visible light irradiation.Results showed that the BiOBr/SF-CA composite film exhibited efficient photocatalytic activity with 99.9%of rhodamine B degradation rate.Moreover,the composite film maintained high catalytic stability because Bi as the active species deposited on the film showed almost no loss.Finally,the possible photocatalytic mechanisms in the BiOBr/SF-CA composite film were speculated through radical-trapping experiments and electron spin resonance testing.
基金the financial support by the National Natural Science Foundation of China(Grant No.21676226)the Natural Science Foundation for Distinguished Young Scholars in Hunan Province(Grant No.2018JJ1023)+1 种基金Key Research and Development Program in Hunan Province(Grant No.2019GK2041)Collaborative Innovation Center of New Chemical Technologies for Environmental Benignity and Efficient Resource Utilization.
文摘In this work,a new mesoporous silicon sulfonic acid catalyst derived from silicic acid has been successfully prepared by the chemical bonding method.The physicochemical properties of mesoporous silicon sulfonic acid catalysts have been systematically characterized using various techniques.The results demonstrate that sulfonic acid groups have been grafted on silicic acid by forming a new chemical bond(Si-O-S).The mesoporous silicon sulfonic acid exhibits excellent catalytic performance and stability in the vapor phase hydroamination reaction of cyclohexene with cyclohexylamine.Cyclohexene conversion of 61% and 97% selectivity to dicyclohexylamine was maintained after running the reaction for over 350 h at 280℃.The developed mesoporous silicon sulfonic acid catalyst shows advantages of low cost,superior acid site accessibility,and long term reactivity stability.Moreover,a possible catalytic hydroamination reaction mechanism over silicon sulfonic acid was suggested.It has been demonstrated that the sulfonic acid groups of the catalyst play an important role in the hydroamination.The present work provides a simple,efficient,and environmentally friendly method for the hydroamination of cyclohexene to valuable dicyclohexylamine,which also shows important industrial application prospects.
基金the National Natural Science Foundation of China(Grant Nos.51573041 and 21776067)the Demonstration Base Project of University-Enterprise Cooperation of Hunan Province(No.145812).
文摘An ion-imprinted sorbent(IIP)was prepared by using Ni^2+ as template,3-[2(2-aminoethylamino)ethylamino]propyl-trimethoxysilane as functional monomer,and silica gel as carrier.The adsorption performance of IIP towards Ni^2+ was investigated.IIP showed a higher adsorption capacity than that of non-imprinted sorbent,and it also exhibited high selectivity for Ni^2+ in the presence of Cu^2+ and Zn^2+ ions.Then,IIP was used to form a dynamic membrane onto the surface of ceramic membrane for treatment of electroplating wastewater containing Ni^2+.Compared with ceramic membrane,IIP dynamic membrane had much higher steady membrane flux,and also rejected Ni^2+ to obtain a lower concentration of Ni2+ in the permeate fluid.Perhaps it is suitable for future practice applications.
