A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment...A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment.The physiochemical properties of composites were characterized thoroughly.It has found that heating temperature and N-doping through NH_3-ambiance pyrolysis significantly influence the visible-light sensitivity and bandgap energy of composites.The catalytic activities of composites were measured by degradation of Methylene Blue(MB)in the presence or absence of H_2O_2 and visible-light irradiation.Our best catalyst(N–TiO_2–Fe_3O_4-biochar)exhibits rapid and high MB removal competency(99.99%)via synergism of adsorption,photodegradation,and Fenton-like reaction.Continuous production of O_2U^-and UOH radicles performs MB degradation and mineralization,confirmed by scavenging experiments and degradation product analysis.The local trap state Ti^(3+),Fe_3O_4,and N-carbon of the catalyst acted as active sites.It has suggested that the Ti^(3+)and N-doped dense carbon layer improve charge separation and shuttle that prolonged photo-Fenton like reaction.Moreover,the catalyst is highly stable,collectible,and recyclable up to 5 cycles with high MB degradation efficiency.This work provides a new insight into the synthesis of highly visible-light sensitized biocharsupported photocatalyst through NH_3-ambiance pyrolysis of NPs-laden biomass.展开更多
The increased contamination of potentially toxic element(PTE)has posed remarkable ecological risks to environment.Application of functionalized biochar for the remediation of PTE contaminated water and soils are of gr...The increased contamination of potentially toxic element(PTE)has posed remarkable ecological risks to environment.Application of functionalized biochar for the remediation of PTE contaminated water and soils are of great concern,and effective strategies are urgently needed to enhance the removal capacity of biochar for PTE.As a novel surface modification technology,the effect of layered double hydroxides(LDH)and sodium dodecyl sulfonate(SDS)on the remediation capacity of biochar for PTE polluted soils and water remains unclear.Sawdust biochar(SB)was coated with Mg and Fe to synthesize the Mg-Fe-LDH functionalized biochar(MFB);thereafter,the MFB was mixed with SDS solution to synthesize the organic-Mg-Fe-LDH biochar(MSB).The potential of SB,MFB,and MSB for remediation of Cd and Pb contaminated soil and water was evaluated in terms of adsorption capacity,immobilization efficiency,and stability.Loading of Mg-Fe-LDH into SB,along with SDS treatment created a regular micro-nano hierarchical structure and enhanced the surface roughness,aromaticity,and hydrophobicity of MSB as compared to SB.MSB exhibited a significantly higher maximum adsorption capacity(mg g^(−1))for water Pb(405.2)and Cd(673.0)than MFB(335.9 for Pb and 209.0 for Cd)and SB(178.2 for Pb and 186.1 for Cd).MSB altered the soluble fraction of Cd/Pb to the residual fraction and thus significantly decreased their mobilization in soil.The higher removal/immobilization efficiency of MSB could be attributed to its alkalinity,and the enhanced synergistic interactions including surface precipitation,ion exchange,complexation,and hydrogen bonding.The resistance to carbon loss by H_(2)O_(2),thermal recalcitrance index R_(50),and degree of graphitization in MSB were significantly improved compared to SB,indicating a more stable carbon fraction sequestered in MSB following aging in soil.These results indicate that MSB could be used for remediation of Cd and Pb contaminated soil and water.展开更多
基金supported by the National Basic Research Program of China (973 Program, 2014CB238903)the National Natural Science Foundation of China (Nos. 41672144, 41173032, and 41373110)
文摘A series of new biochar-supported composite based on the combination of biochar and metallic nanoparticles(NPs)were produced through single-step pyrolysis of FeCl_3–Ti(OBu)_4 laden agar biomass under NH_3 environment.The physiochemical properties of composites were characterized thoroughly.It has found that heating temperature and N-doping through NH_3-ambiance pyrolysis significantly influence the visible-light sensitivity and bandgap energy of composites.The catalytic activities of composites were measured by degradation of Methylene Blue(MB)in the presence or absence of H_2O_2 and visible-light irradiation.Our best catalyst(N–TiO_2–Fe_3O_4-biochar)exhibits rapid and high MB removal competency(99.99%)via synergism of adsorption,photodegradation,and Fenton-like reaction.Continuous production of O_2U^-and UOH radicles performs MB degradation and mineralization,confirmed by scavenging experiments and degradation product analysis.The local trap state Ti^(3+),Fe_3O_4,and N-carbon of the catalyst acted as active sites.It has suggested that the Ti^(3+)and N-doped dense carbon layer improve charge separation and shuttle that prolonged photo-Fenton like reaction.Moreover,the catalyst is highly stable,collectible,and recyclable up to 5 cycles with high MB degradation efficiency.This work provides a new insight into the synthesis of highly visible-light sensitized biocharsupported photocatalyst through NH_3-ambiance pyrolysis of NPs-laden biomass.
基金supported by the Major Scientific and Technological Innovation Project of Shandong Province(2021CXGC011206)Key Research and Development Program of Zhejiang Province,China(2024C03125)the author Esmat F.Ali extends his appreciation to Taif University,Saudi Arabia for supporting this work through project number(TU-DSPP-2024-27).
文摘The increased contamination of potentially toxic element(PTE)has posed remarkable ecological risks to environment.Application of functionalized biochar for the remediation of PTE contaminated water and soils are of great concern,and effective strategies are urgently needed to enhance the removal capacity of biochar for PTE.As a novel surface modification technology,the effect of layered double hydroxides(LDH)and sodium dodecyl sulfonate(SDS)on the remediation capacity of biochar for PTE polluted soils and water remains unclear.Sawdust biochar(SB)was coated with Mg and Fe to synthesize the Mg-Fe-LDH functionalized biochar(MFB);thereafter,the MFB was mixed with SDS solution to synthesize the organic-Mg-Fe-LDH biochar(MSB).The potential of SB,MFB,and MSB for remediation of Cd and Pb contaminated soil and water was evaluated in terms of adsorption capacity,immobilization efficiency,and stability.Loading of Mg-Fe-LDH into SB,along with SDS treatment created a regular micro-nano hierarchical structure and enhanced the surface roughness,aromaticity,and hydrophobicity of MSB as compared to SB.MSB exhibited a significantly higher maximum adsorption capacity(mg g^(−1))for water Pb(405.2)and Cd(673.0)than MFB(335.9 for Pb and 209.0 for Cd)and SB(178.2 for Pb and 186.1 for Cd).MSB altered the soluble fraction of Cd/Pb to the residual fraction and thus significantly decreased their mobilization in soil.The higher removal/immobilization efficiency of MSB could be attributed to its alkalinity,and the enhanced synergistic interactions including surface precipitation,ion exchange,complexation,and hydrogen bonding.The resistance to carbon loss by H_(2)O_(2),thermal recalcitrance index R_(50),and degree of graphitization in MSB were significantly improved compared to SB,indicating a more stable carbon fraction sequestered in MSB following aging in soil.These results indicate that MSB could be used for remediation of Cd and Pb contaminated soil and water.
