A series of Fe/HZSM-5 catalysts with different iron loadings were prepared by impregnation method.Characterization was performed by N2 adsorption-desorption,X-ray diffraction（XRD）,NH3 temperature-programmed desorpt...A series of Fe/HZSM-5 catalysts with different iron loadings were prepared by impregnation method.Characterization was performed by N2 adsorption-desorption,X-ray diffraction（XRD）,NH3 temperature-programmed desorption（NH3-TPD）,temperature-programmed reduction （TPR）,temperature-programmed oxidation（TPO）and thermogravimetry（TG）analysis.Iron content in the synthesized samples varied from 1.1 wt%to 20 wt%.The obtained samples have been used for ethanol conversion into light olefins.It was found that the amount of strong acidity at 300 -5 50-C on Fe-modified samples was decreased,going with another new acid site appearance at 550- 600-C and that Fe/HZSM-5 catalysts were highly selective towards light olefins,especially the 9FZ sample.In addition,Fe-modified catalysts suppressed the conversion of ethanol to aromatics and paraffins and enhanced their anti-carbon deposit ability.展开更多
Emergent plants have been remarkably effective in reducing phosphorus(P)discharge from ecological ditches;however,the treatment and recycling of these residues is a great challenge.In this study,magnetic biochars(MBs,...Emergent plants have been remarkably effective in reducing phosphorus(P)discharge from ecological ditches;however,the treatment and recycling of these residues is a great challenge.In this study,magnetic biochars(MBs,i.e.,MB-A,MB-C,and MB-T)were fabricated from three emergent plant residues(Acorus calamus L.,Canna indica L.,and Thalia dealbata Fraser,respectively)and modified with Fe(II)/Fe(III).Scanning electron microscopy-energy dispersive spectroscopy and X-ray diffraction spectra confirmed the successful loading of Fe_(3)O_(4)and FeO(OH)onto the surfaces of the MBs.Batch adsorption experiments showed that MBs exhibited a higher P adsorption capacity than that of the raw biochars.Within the range of 0.8-43.0 mg L^(−1)in solution,the adsorption capacities of P by MB-A,MB-C,and MB-T were 304.6-5658.8,314.9-6845.6,and 292.8-5590.0 mg kg^(−1),with adsorption efficiencies of 95.2-32.9%,98.4-39.8%,and 91.5-32.5%,respectively.The primary mechanisms that caused P to adsorb onto the MBs were inner-sphere complexation and electrostatic attraction.Low pH conditions were more beneficial for the P adsorption of the MBs,while co-existing anions had a negative impact with the following order:HCO_(3)^(-)>SO_(4)^(2−)>Cl^(−)≈NO_(3)^(−).The P-31 nuclear magnetic resonance results further demonstrated that the main adsorbed P species on the MBs was orthophosphate,followed by orthophosphate monoesters and DNA.Overall,MBs offer a resource utilization strategy for emergent plant residues and P-laden MBs are promising alternative P fertilizers.展开更多
The modification with dark metallic oxide is identified as the crucial strategy to enhance optical absorptions of calcium-based materials for the direct solar-driven thermochemical energy storage.The effect of modific...The modification with dark metallic oxide is identified as the crucial strategy to enhance optical absorptions of calcium-based materials for the direct solar-driven thermochemical energy storage.The effect of modification on the heat release behavior in carbonation of calcium-based material has been widely investigated,but its effect on the heat storage behavior in calcination is lacking of sufficient research,typically for low-cost calcium resource such as carbide slag.The Fe-modified and Mn-modified carbide slags for CaCO_(3)/CaO heat storage were synthesized and their optimum decomposition temperatures,effective heat storage conversions,heat flows and heat storage rates in endothermic stage were investigated.Although the Fe modification exacerbates the CaO sintering due to the formation of Ca_(2)Fe2O5,that is still effective in reducing the regeneration temperature of CaO in CaCO_(3)/CaO cycles.The Mn modification enhances significantly sintering resistance by forming the CaMnO_(3)and its transformation into Ca_(2)MnO_(4).The effective heat storage conversion of Mn-modified carbide slag after 30 cycles is 3.2 times as high as that of untreated carbide slag.Mn-modified carbide slag exhibits the lowest regeneration temperature and the highest heat storage rate after cycles.The loose and stable porous structure of Mn-modified carbide slag contributes to its superior endothermic performance.Therefore,Mn-modified carbide slag seems to be the potential candidate for calcium looping thermochemical heat storage.展开更多
Residual antibiotics in chicken manure may interfere with the stability of anaerobic digestion(AD)and inhibit resource utilization efficiency.In this study,we aimed to enhance chicken manure bio-methanation in AD with...Residual antibiotics in chicken manure may interfere with the stability of anaerobic digestion(AD)and inhibit resource utilization efficiency.In this study,we aimed to enhance chicken manure bio-methanation in AD with highconcentration of sulfamethazine(SMZ)by adding metal(Fe,Co)-modified Enteromorpha-based hydrochar(Co-HC,Fe-HC).The results showed that Fe-HC and Co-HC increased the degree of acidogenesis by 1.25 times and 1.58 times,respectively.The maximum protein concentration in EPS was increased by 47.64%and 72.5%after adding Fe-HC and Co-HC.However,only Co-HC demonstrated notable improvements in both methane production and SMZ removal efficiency.Electrochemical analysis showed that Co-HC possessed a richer variety of oxygen and nitrogen functional groups,along with superior electron exchange capabilities compared to Fe-HC.Furthermore,microbiological assessments revealed that Co-HC enriched syntrophic bacteria(such as Syntrophomonas and Mesotoga),facilitating direct interspecies electron transfer(DIET)and subsequently enhancing biomethane production.The abundance of genes involved in electron transfer increased significantly with Co-HC,with a maximum increase of 75.86%in Co1.5-HC treatment.Additionally,the elimination of antibiotic resistance genes(sul1,sul2)increased by 65.66%in the Co1.5-HC treatment.This study offers a theoretical foundation and empirical support for the synergistic improvement of livestock and poultry manure containing high antibiotic concentrations,thereby helping to overcome challenges posed by recalcitrant substances.展开更多
基金supported by the National Natural Science Foundation of China(No.20963010)the Doctor Fund of Science Research(No.070267)
文摘A series of Fe/HZSM-5 catalysts with different iron loadings were prepared by impregnation method.Characterization was performed by N2 adsorption-desorption,X-ray diffraction（XRD）,NH3 temperature-programmed desorption（NH3-TPD）,temperature-programmed reduction （TPR）,temperature-programmed oxidation（TPO）and thermogravimetry（TG）analysis.Iron content in the synthesized samples varied from 1.1 wt%to 20 wt%.The obtained samples have been used for ethanol conversion into light olefins.It was found that the amount of strong acidity at 300 -5 50-C on Fe-modified samples was decreased,going with another new acid site appearance at 550- 600-C and that Fe/HZSM-5 catalysts were highly selective towards light olefins,especially the 9FZ sample.In addition,Fe-modified catalysts suppressed the conversion of ethanol to aromatics and paraffins and enhanced their anti-carbon deposit ability.
基金the Key Research and Development Project of Science and Technology Department of Zhejiang Province(2023C02016,2023C02019)the National Key Research and Development Program of China(2022YFD1700704-3)Bingtuan Science and Technology Program(2021DB019).
文摘Emergent plants have been remarkably effective in reducing phosphorus(P)discharge from ecological ditches;however,the treatment and recycling of these residues is a great challenge.In this study,magnetic biochars(MBs,i.e.,MB-A,MB-C,and MB-T)were fabricated from three emergent plant residues(Acorus calamus L.,Canna indica L.,and Thalia dealbata Fraser,respectively)and modified with Fe(II)/Fe(III).Scanning electron microscopy-energy dispersive spectroscopy and X-ray diffraction spectra confirmed the successful loading of Fe_(3)O_(4)and FeO(OH)onto the surfaces of the MBs.Batch adsorption experiments showed that MBs exhibited a higher P adsorption capacity than that of the raw biochars.Within the range of 0.8-43.0 mg L^(−1)in solution,the adsorption capacities of P by MB-A,MB-C,and MB-T were 304.6-5658.8,314.9-6845.6,and 292.8-5590.0 mg kg^(−1),with adsorption efficiencies of 95.2-32.9%,98.4-39.8%,and 91.5-32.5%,respectively.The primary mechanisms that caused P to adsorb onto the MBs were inner-sphere complexation and electrostatic attraction.Low pH conditions were more beneficial for the P adsorption of the MBs,while co-existing anions had a negative impact with the following order:HCO_(3)^(-)>SO_(4)^(2−)>Cl^(−)≈NO_(3)^(−).The P-31 nuclear magnetic resonance results further demonstrated that the main adsorbed P species on the MBs was orthophosphate,followed by orthophosphate monoesters and DNA.Overall,MBs offer a resource utilization strategy for emergent plant residues and P-laden MBs are promising alternative P fertilizers.
基金supported by the National Natural Science Foundation of China(62273213,52006128)Shandong Provincial Natural Science Foundation(ZR2023QE196)+4 种基金Qingdao Natural Science Foundation(23-2-1-87-zyyd-jch)Qingdao Postdoctoral Innovation Project(QDBSH20230102003)Natural Science Foundation of Shandong Province for Innovation and Development Joint Funds(ZR2022LZH001)Youth Innovation Team of universities in Shandong Province(2022KJ221)Project of Shandong Province Higher Educational Young Innovative Talent Introduction and Cultivation Team(Hydrogen energy chemistry innovation team)。
文摘The modification with dark metallic oxide is identified as the crucial strategy to enhance optical absorptions of calcium-based materials for the direct solar-driven thermochemical energy storage.The effect of modification on the heat release behavior in carbonation of calcium-based material has been widely investigated,but its effect on the heat storage behavior in calcination is lacking of sufficient research,typically for low-cost calcium resource such as carbide slag.The Fe-modified and Mn-modified carbide slags for CaCO_(3)/CaO heat storage were synthesized and their optimum decomposition temperatures,effective heat storage conversions,heat flows and heat storage rates in endothermic stage were investigated.Although the Fe modification exacerbates the CaO sintering due to the formation of Ca_(2)Fe2O5,that is still effective in reducing the regeneration temperature of CaO in CaCO_(3)/CaO cycles.The Mn modification enhances significantly sintering resistance by forming the CaMnO_(3)and its transformation into Ca_(2)MnO_(4).The effective heat storage conversion of Mn-modified carbide slag after 30 cycles is 3.2 times as high as that of untreated carbide slag.Mn-modified carbide slag exhibits the lowest regeneration temperature and the highest heat storage rate after cycles.The loose and stable porous structure of Mn-modified carbide slag contributes to its superior endothermic performance.Therefore,Mn-modified carbide slag seems to be the potential candidate for calcium looping thermochemical heat storage.
基金supported by the National High Technology Research and Development Program of China(2022YFC3700187)National Natural Science Foundation of China(U1806216 and 51608304)Young Scholars Program of Shandong University(2018WLJH53).
文摘Residual antibiotics in chicken manure may interfere with the stability of anaerobic digestion(AD)and inhibit resource utilization efficiency.In this study,we aimed to enhance chicken manure bio-methanation in AD with highconcentration of sulfamethazine(SMZ)by adding metal(Fe,Co)-modified Enteromorpha-based hydrochar(Co-HC,Fe-HC).The results showed that Fe-HC and Co-HC increased the degree of acidogenesis by 1.25 times and 1.58 times,respectively.The maximum protein concentration in EPS was increased by 47.64%and 72.5%after adding Fe-HC and Co-HC.However,only Co-HC demonstrated notable improvements in both methane production and SMZ removal efficiency.Electrochemical analysis showed that Co-HC possessed a richer variety of oxygen and nitrogen functional groups,along with superior electron exchange capabilities compared to Fe-HC.Furthermore,microbiological assessments revealed that Co-HC enriched syntrophic bacteria(such as Syntrophomonas and Mesotoga),facilitating direct interspecies electron transfer(DIET)and subsequently enhancing biomethane production.The abundance of genes involved in electron transfer increased significantly with Co-HC,with a maximum increase of 75.86%in Co1.5-HC treatment.Additionally,the elimination of antibiotic resistance genes(sul1,sul2)increased by 65.66%in the Co1.5-HC treatment.This study offers a theoretical foundation and empirical support for the synergistic improvement of livestock and poultry manure containing high antibiotic concentrations,thereby helping to overcome challenges posed by recalcitrant substances.
