The biosorption potential of dried activated sludge as a biosorbent for zinc（Ⅱ） removal from aqueous solution was investigated.The effects of initial pH,contact time,initial zinc ion concentration,and adsorbent dos...The biosorption potential of dried activated sludge as a biosorbent for zinc（Ⅱ） removal from aqueous solution was investigated.The effects of initial pH,contact time,initial zinc ion concentration,and adsorbent dosage on the biosorption processes were determined,and the equilibrium data were modeled by the Langmuir and Freundlich isotherms.The Langmuir isotherm model （R 2=0.999） was proved to fit the equilibrium data much better than the Freundlich isotherm model （R 2=0.918）.The monolayer adsorption capacity of dried activated sludge for zinc（Ⅱ） was found to be 17.86 mg/g at pH of 5 and 25°C.The kinetic data were tested using pseudo firstand second-order models.The results suggested that the pseudo second-order model （R 2 〉 0.999） was better for the description of the adsorption behavior of zinc（Ⅱ） onto the dried activated sludge.Fourier transform infrared spectral analysis showed that the dominant mechanism of zinc（Ⅱ） biosorption onto the dried activated sludge was the binding between amide groups and zinc ions.展开更多
Oxygen vacancy plays vital roles in regulating the electronic and charge distribution of the oxygen deficient materials.Herein,abundant oxygen vacancies are created during assembling the two-dimensional(2D)ultra-thin ...Oxygen vacancy plays vital roles in regulating the electronic and charge distribution of the oxygen deficient materials.Herein,abundant oxygen vacancies are created during assembling the two-dimensional(2D)ultra-thin Bi_(2)MoO_(6) nanoflakes into three dimensional(3D)Bi_(2)MoO_(6) nanospheres,resulting in significantly improved performance for photocatalytical conversion of CO_(2) into liquid hydrocarbons.The increased performance is contributed by two primary sites,namely the abundant oxygen vacancy and the exposed molybdenum(Mo)atom induced by oxygen-migration,as revealed by the theoretical calculation.The oxygen vacancy(Ov)and uncovered Mo atom serving as dual binding sites for trapping CO_(2) molecules render the synchronous fixation-reduction process,resulting in the decline of activation energy for CO_(2) reduction from 2.15 eV on bulk Bi_(2)MoO_(6) to 1.42 eV on Ov-rich Bi_(2)MoO_(6).Such a striking decrease in the activation energy induces the efficient selective generation of liquid hydrocarbons,especially the methanol(C_(2)H_(5) OH)and ethanol(CH_(3) OH).The yields of CH_(3) OH and C_(2)H_(5) OH over the optimal Ov-Bi_(2)MoO_(6) is high up to 106.5 and 10.3μmol g^(-1) respectively,greatly outperforming that on the Bulk-Bi_(2)MoO_(6).展开更多
Herein,Co_(2)P nanorods(NRs)with exposure to high-index facets(HIFs)were prepared by a special assembly-calcination method using thioacetamide(TAA)as a structure-directing reagent.The analysis of adsorption energies o...Herein,Co_(2)P nanorods(NRs)with exposure to high-index facets(HIFs)were prepared by a special assembly-calcination method using thioacetamide(TAA)as a structure-directing reagent.The analysis of adsorption energies of S atoms on different facets as well as the surface energies of Co_(2)P indicate that the HIFs become more stable after adsorbing S atoms.With rich unsaturated sites on HIFs,the photochemical reduction rate of CO_(2)over Co_(2)P NRs is 14.5 mmol h^(-1)g^(-1)for the production of CO within 3 h.The analysis of electron transfer,bond lengths,bond angles and adsorption energies indicate that the CO_(2)molecules are more easily adsorbed and activated on the HIFs.The free energy calculations and d band theory demonstrate that the HIFs are conducive to reducing the formation energy barriers as well as improving the stability of the intermediate^(*)COOH,then enhancing the catalytic performance of CO_(2)reduction.展开更多
In this article,we present our research results on chemical fixation of CO_(2) using organobismuth compounds.We fabricated bismuth biphenoate complex,Zn-Mg-Al composite oxides,and SBA-15 or Al-SBA-15 immobilized hydro...In this article,we present our research results on chemical fixation of CO_(2) using organobismuth compounds.We fabricated bismuth biphenoate complex,Zn-Mg-Al composite oxides,and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO_(2) cycloaddition onto epoxides.The hypervalent bismuth compounds show good ability for association and dissociation with CO_(2).The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction.The heterogeneous catalysts,viz.Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid,are efficient for the synthesis of cyclic carbonate from CO_(2) and epoxide.It is found that the presence of a trace amount of water can improve the catalytic activity of the immobilized ionic liquid.展开更多
In recent years,microbiological treatment to remediate contamination by heavy metals has aroused public attention as such pollution has seriously threatens ecosystems and human health and impedes sustainable developme...In recent years,microbiological treatment to remediate contamination by heavy metals has aroused public attention as such pollution has seriously threatens ecosystems and human health and impedes sustainable development.However,the aspect of actual industrial wastewater and solid waste remediation by microorganisms is not explored sufficiently.And what we focus on is technical field of microbial remediation.Therefore,in this review,we discuss and summarize heavy metal treatment via microbiological approaches in different media,including wastewater,solid waste from industrial factories and polluted sites.We also clarify the technical applicability from the perspective of biosorption,bioleaching,biominerization,etc.In particular,the exploration of the combination of microbiological approaches with chemical methods or phytoextraction are scrutinized in this review relative to real waste heavy metal remediation.Furthermore,we highlight the importance of hyperaccumulator endophytes.展开更多
The adsorbents–adsorbates interaction is critical for resourcelization in heavy metal wastewater treatment.Nevertheless,it is still indistinct to depict the impact of metal center effect on heavy metals removal perfo...The adsorbents–adsorbates interaction is critical for resourcelization in heavy metal wastewater treatment.Nevertheless,it is still indistinct to depict the impact of metal center effect on heavy metals removal performance in metal-organic frameworks(MOFs)-based adsorbents.Herein,a series of MOFs with different metal centers of Mg(II),La(III),and Zr(IV)are rationally designed,and the effect of electronic structure on the Sb(V)removal performance is systematically investigated.The obtained La-MGs achieve Sb(V)adsorption capacity of 897.6 mg/g,which is about 1.2 and 4.5 times above average than those of Zr-MGs and Mg-MGs,respectively.On account of more edge adsorption sites achieve,the sites utilization efficiency of La-MGs(92.1%)is much better than Zr-MGs(75.0%)and Mg-MGs(20.4%).Furthermore,density functional theory(DFT)calculations reveal that La-MGs are more active than Mg-MGs and Zr-MGs,owing to the lower adsorption energy,higher charge transfer,and stronger bonding interaction,which will promote the Sb(V)removal performance.The experimental results in practical water indicate that La-MGs effectively capture antimony at low concentration,reaching drinking water standard in samples from Ganjiang River.This study opens an avenue for atomic-level insight into high-efficient absorbents design for water treatment from electronic structuremodification of active centers.展开更多
In order to achieve high-efficiency conversion of CO_(2) into valuable chemicals,and to exploit new applications of organobismuth compounds,cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f][1,5]azabis...In order to achieve high-efficiency conversion of CO_(2) into valuable chemicals,and to exploit new applications of organobismuth compounds,cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f][1,5]azabismocine framework was examined for the first time for the coupling of CO_(2) into cyclic carbonates,using terminal epoxides as substrates and tetrabutylammonium halide as co-catalyst in a solvent-free environment under mild conditions.It is shown that the catalyst exhibited high activity and selectivity for the coupling reaction of CO_(2) with a wide range of terminal epoxide.The selectivity of propylene carbonates could reach 100%,and the maximum turnover frequency was up to 10740 h^(-1) at 120℃ and 3 MPa CO_(2) pressure when tetrabutylammonium iodide was used as co-catalyst.Moreover,the catalyst is environment friendly,resistant to air and water,and can be readily reused and recycled without any loss of activity,demonstrating a potential in industrial application.展开更多
基金supported by the National Natural Science Foundation of China (No. 50778066)the National Science and Technology Support Program of China(No. 2006BAJ04A13)+1 种基金the Program for New Century Excellent Talents in University from the Ministry of Education of China (No. NCET-08-0181)the China Postdoctoral Science Foundation (No. 200801338)
文摘The biosorption potential of dried activated sludge as a biosorbent for zinc（Ⅱ） removal from aqueous solution was investigated.The effects of initial pH,contact time,initial zinc ion concentration,and adsorbent dosage on the biosorption processes were determined,and the equilibrium data were modeled by the Langmuir and Freundlich isotherms.The Langmuir isotherm model （R 2=0.999） was proved to fit the equilibrium data much better than the Freundlich isotherm model （R 2=0.918）.The monolayer adsorption capacity of dried activated sludge for zinc（Ⅱ） was found to be 17.86 mg/g at pH of 5 and 25°C.The kinetic data were tested using pseudo firstand second-order models.The results suggested that the pseudo second-order model （R 2 〉 0.999） was better for the description of the adsorption behavior of zinc（Ⅱ） onto the dried activated sludge.Fourier transform infrared spectral analysis showed that the dominant mechanism of zinc（Ⅱ） biosorption onto the dried activated sludge was the binding between amide groups and zinc ions.
基金financially supported by the National Natural Science Foundation of China(Grants 52072165,52070092,51662031)。
文摘Oxygen vacancy plays vital roles in regulating the electronic and charge distribution of the oxygen deficient materials.Herein,abundant oxygen vacancies are created during assembling the two-dimensional(2D)ultra-thin Bi_(2)MoO_(6) nanoflakes into three dimensional(3D)Bi_(2)MoO_(6) nanospheres,resulting in significantly improved performance for photocatalytical conversion of CO_(2) into liquid hydrocarbons.The increased performance is contributed by two primary sites,namely the abundant oxygen vacancy and the exposed molybdenum(Mo)atom induced by oxygen-migration,as revealed by the theoretical calculation.The oxygen vacancy(Ov)and uncovered Mo atom serving as dual binding sites for trapping CO_(2) molecules render the synchronous fixation-reduction process,resulting in the decline of activation energy for CO_(2) reduction from 2.15 eV on bulk Bi_(2)MoO_(6) to 1.42 eV on Ov-rich Bi_(2)MoO_(6).Such a striking decrease in the activation energy induces the efficient selective generation of liquid hydrocarbons,especially the methanol(C_(2)H_(5) OH)and ethanol(CH_(3) OH).The yields of CH_(3) OH and C_(2)H_(5) OH over the optimal Ov-Bi_(2)MoO_(6) is high up to 106.5 and 10.3μmol g^(-1) respectively,greatly outperforming that on the Bulk-Bi_(2)MoO_(6).
基金financially supported by the National Natural Science Foundation of China(52072165,51662031 and 51720105001)the general project of science and technology research of Jiangxi Provincial Department of Education(DA202102160)+1 种基金the project funded by China Postdoctoral Science Foundation(2019M653583)the starting research fund(EA202102179)。
文摘Herein,Co_(2)P nanorods(NRs)with exposure to high-index facets(HIFs)were prepared by a special assembly-calcination method using thioacetamide(TAA)as a structure-directing reagent.The analysis of adsorption energies of S atoms on different facets as well as the surface energies of Co_(2)P indicate that the HIFs become more stable after adsorbing S atoms.With rich unsaturated sites on HIFs,the photochemical reduction rate of CO_(2)over Co_(2)P NRs is 14.5 mmol h^(-1)g^(-1)for the production of CO within 3 h.The analysis of electron transfer,bond lengths,bond angles and adsorption energies indicate that the CO_(2)molecules are more easily adsorbed and activated on the HIFs.The free energy calculations and d band theory demonstrate that the HIFs are conducive to reducing the formation energy barriers as well as improving the stability of the intermediate^(*)COOH,then enhancing the catalytic performance of CO_(2)reduction.
基金The financial supports of the National Natural Science Foundation of China(Grant Nos.20507005 and 20873038)Outstanding Young Research Award of National Natural Science Foundation of China(Grant No.E50725825)Hong Kong Baptist University(FRG/08-09/II-09)。
文摘In this article,we present our research results on chemical fixation of CO_(2) using organobismuth compounds.We fabricated bismuth biphenoate complex,Zn-Mg-Al composite oxides,and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO_(2) cycloaddition onto epoxides.The hypervalent bismuth compounds show good ability for association and dissociation with CO_(2).The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction.The heterogeneous catalysts,viz.Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid,are efficient for the synthesis of cyclic carbonate from CO_(2) and epoxide.It is found that the presence of a trace amount of water can improve the catalytic activity of the immobilized ionic liquid.
基金National Natural Science Foundation of China(Grant NO.51968048).
文摘In recent years,microbiological treatment to remediate contamination by heavy metals has aroused public attention as such pollution has seriously threatens ecosystems and human health and impedes sustainable development.However,the aspect of actual industrial wastewater and solid waste remediation by microorganisms is not explored sufficiently.And what we focus on is technical field of microbial remediation.Therefore,in this review,we discuss and summarize heavy metal treatment via microbiological approaches in different media,including wastewater,solid waste from industrial factories and polluted sites.We also clarify the technical applicability from the perspective of biosorption,bioleaching,biominerization,etc.In particular,the exploration of the combination of microbiological approaches with chemical methods or phytoextraction are scrutinized in this review relative to real waste heavy metal remediation.Furthermore,we highlight the importance of hyperaccumulator endophytes.
基金the National Natural Science Foundation of China(Nos.51938007,51720105001,52100039,52125002,and 52100043)the Youth Natural Science Foundation of Hunan Province(No.2020JJ5076).
文摘The adsorbents–adsorbates interaction is critical for resourcelization in heavy metal wastewater treatment.Nevertheless,it is still indistinct to depict the impact of metal center effect on heavy metals removal performance in metal-organic frameworks(MOFs)-based adsorbents.Herein,a series of MOFs with different metal centers of Mg(II),La(III),and Zr(IV)are rationally designed,and the effect of electronic structure on the Sb(V)removal performance is systematically investigated.The obtained La-MGs achieve Sb(V)adsorption capacity of 897.6 mg/g,which is about 1.2 and 4.5 times above average than those of Zr-MGs and Mg-MGs,respectively.On account of more edge adsorption sites achieve,the sites utilization efficiency of La-MGs(92.1%)is much better than Zr-MGs(75.0%)and Mg-MGs(20.4%).Furthermore,density functional theory(DFT)calculations reveal that La-MGs are more active than Mg-MGs and Zr-MGs,owing to the lower adsorption energy,higher charge transfer,and stronger bonding interaction,which will promote the Sb(V)removal performance.The experimental results in practical water indicate that La-MGs effectively capture antimony at low concentration,reaching drinking water standard in samples from Ganjiang River.This study opens an avenue for atomic-level insight into high-efficient absorbents design for water treatment from electronic structuremodification of active centers.
基金This work was supported by the National Natural Science Foundation of China(Grant No.20507005)Outstanding Young Research Award of National Natural Science Foundation of China(Grant No.E50725825).
文摘In order to achieve high-efficiency conversion of CO_(2) into valuable chemicals,and to exploit new applications of organobismuth compounds,cationic organobismuth complex with 5,6,7,12-tetrahydrodibenz[c,f][1,5]azabismocine framework was examined for the first time for the coupling of CO_(2) into cyclic carbonates,using terminal epoxides as substrates and tetrabutylammonium halide as co-catalyst in a solvent-free environment under mild conditions.It is shown that the catalyst exhibited high activity and selectivity for the coupling reaction of CO_(2) with a wide range of terminal epoxide.The selectivity of propylene carbonates could reach 100%,and the maximum turnover frequency was up to 10740 h^(-1) at 120℃ and 3 MPa CO_(2) pressure when tetrabutylammonium iodide was used as co-catalyst.Moreover,the catalyst is environment friendly,resistant to air and water,and can be readily reused and recycled without any loss of activity,demonstrating a potential in industrial application.
