Amino-functionalized Fe3O4@mesoporous SiO/ core-shell composite microspheres NH2-MS in created in multiple synthesis steps have been investigated for Pb(Ⅱ) and Cd(Ⅱ) adsorption. The microspheres were characteriz...Amino-functionalized Fe3O4@mesoporous SiO/ core-shell composite microspheres NH2-MS in created in multiple synthesis steps have been investigated for Pb(Ⅱ) and Cd(Ⅱ) adsorption. The microspheres were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), N2 adsorption-desorption, zeta potential measurements and vibrating sample magnetometer. Batch adsorption tests indicated that NH2-MS exhibited higher adsorption affinity toward Pb(Ⅱ) and Cd(Ⅱ) than MS did. The Langmuir model could fit the adsorption isotherm very well with maximum adsorption capacity of 128.21 and 51.81 mg/g for Pb(Ⅱ) and Cd(Ⅱ), respectively, implying that adsorption processes involved monolayer adsorption. Pb(Ⅱ) and Cd(Ⅱ) adsorption could be well described by the pseudo second-order kinetics model, and was found to be strongly dependent on pH and humic acid. The Pb(Ⅱ)- and Cd(Ⅱ)-loaded microspheres were effectively desorbed using 0.01 mol/L HC1 or EDTA solution. NH2-MS have promise for use as adsorbents in the removal of Pb(Ⅱ) and Cd(Ⅱ) in wastewater treatment processes.展开更多
Hydrogen sulfide(H_(2)S)is an industrial exhausted gas that is highly toxic to humans and the environment.Combining desulfurization and fabrication of cathode materials for lithium-sulfur batteries(LSBs)can solve this...Hydrogen sulfide(H_(2)S)is an industrial exhausted gas that is highly toxic to humans and the environment.Combining desulfurization and fabrication of cathode materials for lithium-sulfur batteries(LSBs)can solve this issue with a double benefit.Herein,the amino-functionalized lotus root-like carbon nanofibers(NH_(2)-PLCNFs)are prepared by the amination of electrospinning carbon nanofibers under dielectric barrier discharge plasma.Selective catalytic oxidation of H_(2)S to elemental sulfur(S)is achieved over the metalfree NH_(2)-PLCNFs catalyst,and the obtained composite S@NH_(2)-PLCNFs is further used as cathode in LSBs.NH_(2)-PLCNFs enable efficient desulfurization(removal capacity as high as 3.46 g H_(2)S g^(−1) catalyst)and strongly covalent stabilization of S on modified carbon nanofibers.LSBs equipped with S@NH_(2)-PLCNFs deliver a high specific capacity of 705.8 mA h g^(−1) at 1 C after 1000 cycles based on the spatial confinement and the covalent stabilization of electroactive materials on amino-functionalized porous carbon matrix.It is revealed that S@NH_(2)-PLCNFs obtained by this kind of chemical vapor deposition leads to a more homogeneous S distribution and superior electrochemical performance to the sample S/NH_(2)-PLCNF-M prepared by the traditional molten infusion.This work opens a new avenue for the combination of environment protection and energy storage.展开更多
The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterif...The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol.γ-Aminopropyltriethoxysilane(APTES)was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups,and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic bonding.The Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the modifications.The amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization,which promoted the dispersity,abundance,as well as the stability of the acid sites.The tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites,and the protons from the immobilized HPW acted as the moderate or strong Brønsted acid sites.An optimized TBC yield of 96.2%(mol)with a conversion of-COOH of 98.1%(mol)was achieved at 150℃for 6 h over the HPW immobilized on amino-functionalized TS-1.The catalyst exhibited good stability after four consecutive reaction runs,where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW.展开更多
Excessive fluoride anions in drinking water are toxic to the health of human beings.In this article,an effective fluoride removal adsorbent on the basis of amino-functionalized porous polydivinylbenzene(PDVB)was prepa...Excessive fluoride anions in drinking water are toxic to the health of human beings.In this article,an effective fluoride removal adsorbent on the basis of amino-functionalized porous polydivinylbenzene(PDVB)was prepared through low cost processes,which included solvothermal preparation of porous PDVB and subsequent surface amino-functionalization.The obtained amino-functionalized porous PDVB(A-PDVB)has high surface area of 443 m2 g1 and high adsorption capacity towards fluoride anion up to 105.9 mg g1.Considering adsorbents surface area,the adsorption capacity per unit surface area of A-PDVB is 0.24 mg m2 which is more than 4 times of porous PDVB(0.058 mg m2).The enhanced adsorption performance of A-PDVB was due to amino groups electrostatic interaction coupled with hydrogen bond binding with fluoride anions.In addition,the aminofunctionalized porous PDVB could be regenerated in high efficiency under alkaline conditions.This work not only exhibits the possibility of A-PDVB for application as an environment-friendly adsorbent for fluoride removal but also gives an insight into understanding mechanism of the fluoride anions adsorption onto aminofunctionalized porous PDVB.展开更多
Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch ...Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode.This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heterogeneous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and durability in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports.展开更多
以月桂酸为阴离子表面活性剂,3-胺丙基三乙氧基硅烷(APTES)为共结构导向剂,合成了高含量氨基功能化介孔氧化硅材料(AFMS)。以AFMS为吸附剂对溶液中酸性橙7(AO7)进行吸附,对影响AO7吸附效率的相关因素进行了详细研究,结果表明,溶液p H值...以月桂酸为阴离子表面活性剂,3-胺丙基三乙氧基硅烷(APTES)为共结构导向剂,合成了高含量氨基功能化介孔氧化硅材料(AFMS)。以AFMS为吸附剂对溶液中酸性橙7(AO7)进行吸附,对影响AO7吸附效率的相关因素进行了详细研究,结果表明,溶液p H值及温度影响较大。吸附动力学表明,本研究中合成的AFMS对AO7的吸附速率极快。Sips吸附模型对吸附等温线模拟效果最好,从中可知AO7在样品D(由3.0 m L正硅酸乙酯及1.4 m L APTES合成)上的最大吸附量为1.26 mmol·g-1,远远高于相关文献报道的值。此外,通过吸-脱附循环实验证明,样品D具有良好的稳定性。展开更多
基金supported by the National Natural Science Foundation of China (No. 21007048)the Key Projects in the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period (No. 2012BAF03B06,2012BAJ25B06)partial fund of the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No. PCRRY11011,PCRRF11003)
文摘Amino-functionalized Fe3O4@mesoporous SiO/ core-shell composite microspheres NH2-MS in created in multiple synthesis steps have been investigated for Pb(Ⅱ) and Cd(Ⅱ) adsorption. The microspheres were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), N2 adsorption-desorption, zeta potential measurements and vibrating sample magnetometer. Batch adsorption tests indicated that NH2-MS exhibited higher adsorption affinity toward Pb(Ⅱ) and Cd(Ⅱ) than MS did. The Langmuir model could fit the adsorption isotherm very well with maximum adsorption capacity of 128.21 and 51.81 mg/g for Pb(Ⅱ) and Cd(Ⅱ), respectively, implying that adsorption processes involved monolayer adsorption. Pb(Ⅱ) and Cd(Ⅱ) adsorption could be well described by the pseudo second-order kinetics model, and was found to be strongly dependent on pH and humic acid. The Pb(Ⅱ)- and Cd(Ⅱ)-loaded microspheres were effectively desorbed using 0.01 mol/L HC1 or EDTA solution. NH2-MS have promise for use as adsorbents in the removal of Pb(Ⅱ) and Cd(Ⅱ) in wastewater treatment processes.
基金financial support from projects funded by the National Natural Science Foundation of China(22179017,52172038).
文摘Hydrogen sulfide(H_(2)S)is an industrial exhausted gas that is highly toxic to humans and the environment.Combining desulfurization and fabrication of cathode materials for lithium-sulfur batteries(LSBs)can solve this issue with a double benefit.Herein,the amino-functionalized lotus root-like carbon nanofibers(NH_(2)-PLCNFs)are prepared by the amination of electrospinning carbon nanofibers under dielectric barrier discharge plasma.Selective catalytic oxidation of H_(2)S to elemental sulfur(S)is achieved over the metalfree NH_(2)-PLCNFs catalyst,and the obtained composite S@NH_(2)-PLCNFs is further used as cathode in LSBs.NH_(2)-PLCNFs enable efficient desulfurization(removal capacity as high as 3.46 g H_(2)S g^(−1) catalyst)and strongly covalent stabilization of S on modified carbon nanofibers.LSBs equipped with S@NH_(2)-PLCNFs deliver a high specific capacity of 705.8 mA h g^(−1) at 1 C after 1000 cycles based on the spatial confinement and the covalent stabilization of electroactive materials on amino-functionalized porous carbon matrix.It is revealed that S@NH_(2)-PLCNFs obtained by this kind of chemical vapor deposition leads to a more homogeneous S distribution and superior electrochemical performance to the sample S/NH_(2)-PLCNF-M prepared by the traditional molten infusion.This work opens a new avenue for the combination of environment protection and energy storage.
基金supported by the National Natural Science Foundation of China(21978089)the Program of Shanghai Academic/Technology Research Leader(21XD1433000)Key Research and Development Program of Xinjiang Uygur Autonomous Region(2022B01032-1).
文摘The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol.γ-Aminopropyltriethoxysilane(APTES)was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups,and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic bonding.The Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the modifications.The amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization,which promoted the dispersity,abundance,as well as the stability of the acid sites.The tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites,and the protons from the immobilized HPW acted as the moderate or strong Brønsted acid sites.An optimized TBC yield of 96.2%(mol)with a conversion of-COOH of 98.1%(mol)was achieved at 150℃for 6 h over the HPW immobilized on amino-functionalized TS-1.The catalyst exhibited good stability after four consecutive reaction runs,where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW.
基金supported by the National Natural Science Foundation of China(Grant No.21976003)the Major Project of Natural Science Research in Colleges and Universities of Anhui Province(Grant No.KJ2019ZD51)+1 种基金the Key Research and Development Projects in Anhui Province(Grant No.201904b11020041,1708085QE120)the Academic Funding Project for Top Talents in Colleges and Universities of Anhui Province(Grant No.gxbjZD2020077).
文摘Excessive fluoride anions in drinking water are toxic to the health of human beings.In this article,an effective fluoride removal adsorbent on the basis of amino-functionalized porous polydivinylbenzene(PDVB)was prepared through low cost processes,which included solvothermal preparation of porous PDVB and subsequent surface amino-functionalization.The obtained amino-functionalized porous PDVB(A-PDVB)has high surface area of 443 m2 g1 and high adsorption capacity towards fluoride anion up to 105.9 mg g1.Considering adsorbents surface area,the adsorption capacity per unit surface area of A-PDVB is 0.24 mg m2 which is more than 4 times of porous PDVB(0.058 mg m2).The enhanced adsorption performance of A-PDVB was due to amino groups electrostatic interaction coupled with hydrogen bond binding with fluoride anions.In addition,the aminofunctionalized porous PDVB could be regenerated in high efficiency under alkaline conditions.This work not only exhibits the possibility of A-PDVB for application as an environment-friendly adsorbent for fluoride removal but also gives an insight into understanding mechanism of the fluoride anions adsorption onto aminofunctionalized porous PDVB.
基金the support of the National Natural Science Foundation of China (20222809, 21978146)TsinghuaFoshan Innovation Special Fund (2021THFS0214)。
文摘Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode.This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heterogeneous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and durability in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports.
文摘以月桂酸为阴离子表面活性剂,3-胺丙基三乙氧基硅烷(APTES)为共结构导向剂,合成了高含量氨基功能化介孔氧化硅材料(AFMS)。以AFMS为吸附剂对溶液中酸性橙7(AO7)进行吸附,对影响AO7吸附效率的相关因素进行了详细研究,结果表明,溶液p H值及温度影响较大。吸附动力学表明,本研究中合成的AFMS对AO7的吸附速率极快。Sips吸附模型对吸附等温线模拟效果最好,从中可知AO7在样品D(由3.0 m L正硅酸乙酯及1.4 m L APTES合成)上的最大吸附量为1.26 mmol·g-1,远远高于相关文献报道的值。此外,通过吸-脱附循环实验证明,样品D具有良好的稳定性。