Enhancing the separation efficiency of photogenerated carriers is propitious for the promotion of photocatalytic hydrogen production from formic acid decomposition.Herein,MoS2/Zn3In2S6(MoS2/ZIS6)composite photocatalys...Enhancing the separation efficiency of photogenerated carriers is propitious for the promotion of photocatalytic hydrogen production from formic acid decomposition.Herein,MoS2/Zn3In2S6(MoS2/ZIS6)composite photocatalysts containing varying mass percentages of MoS2 were obtained by a straightforward synthetic method.The results confirmed that MoS2,as a cocatalyst,markedly promoted the photogenerated charge separation efficiency and visible light-driven hydrogen production activity of ZIS6(λ>400 nm).Specifically,the as-prepared 0.5%MoS2/ZIS6 photocatalyst exhibited the highest photocatalytic hydrogen production rate(74.25μmol·h^-1),which was approximately 4.3 times higher than that of ZIS6(17.47μmol·h^-1).The excellent performance of the 0.5%MoS2/ZIS6 photocatalyst may be due to the fact that MoS2 has a low Fermi energy level and can thus enrich photogenerated electrons from ZIS6,and furthermore reduce H+derived from formic acid,to form hydrogen.The structure and morphology of the MoS2/ZIS6 photocatalysts and the reactive species were determined by X-ray diffraction,transmission electron microscopy,and field emission scanning electron microscopy,among others;a plausible mechanistic rationale is discussed based on the results.展开更多
Hydrogen is recognized as a promising energy scours in the close future.Online hydrogen preparation from formic acid under mild reaction conditions causes extensive interests.Mo_(2)C and metal(Fe,Ni,Co,K)doped Mo_(2)C...Hydrogen is recognized as a promising energy scours in the close future.Online hydrogen preparation from formic acid under mild reaction conditions causes extensive interests.Mo_(2)C and metal(Fe,Ni,Co,K)doped Mo_(2)C on granular activated carbon(GAC)were prepared and used as heterogeneous catalysts for H2 generation from formic acid on a fixed bed reactor at 100–250°C.The formic acid conversions on doped Mo_(2)C-Me/GAC are clearly improved,especially at lower reaction temperatures.Co doping presents outstanding effect on H2 selectivity and conversion rate compared to Ni and Fe.A 56.3%formic acid conversion was reached on Mo_(2)C-Co/GAC at 100°C,which triples that on Mo_(2)C/GAC at the same temperature.At 150°C,a high formic acid conversion over 90%was reached on Mo_(2)C-Co/GAC.These long lifetime catalysts with no precious metal provide a low cost route to hydrogen production from formic acid.展开更多
Formic acid(FA)has come to be considered a potential candidate for hydrogen storage,and the development of efficient catalysts for H2releasing is crucial for realizing the sustainable process from FA.Herein,we have de...Formic acid(FA)has come to be considered a potential candidate for hydrogen storage,and the development of efficient catalysts for H2releasing is crucial for realizing the sustainable process from FA.Herein,we have developed the ultrafine Pd nanoparticle(NPs)with amine-functionalized carbon as a support,which was found to show an excellent catalytic activity in H_(2)generation from FA dehydrogenation.The synergetic mechanism between amine-group and Pd active site was demonstrated to facilitate H2generation byβ-hydride elimination.Moreover,the texture of support for Pd NPs also plays an important role in determining the reactivity of FA,since the diffusion of gaseous products makes the kinetics of diffusion as a challenge in this high performance Pd catalysts.As a result,the as-prepared Pd/NH_(2)-TPC catalyst with the small sized Pd nanoparticles and the hierarchically porous structures shows a turnover of frequency(TOF)value of 4312 h^(-1)for the additive-free FA dehydrogenation at room temperature,which is comparable to the most promising heterogeneous catalysts.Our results demonstrated that the intrinsic catalytic activities of active site as well as the porous structure of support are both important factors in determining catalytic performances in H2generation from FA dehydrogenation,which is also helpful to develop high-activity catalysts for other advanced gas-liquid-solid reactions systems.展开更多
The absorption process in acrylic acid production was water-intensive.The concentration of acrylic acid before distillation process was low,which induced to large amount of wastewater and enormous energy consumption.I...The absorption process in acrylic acid production was water-intensive.The concentration of acrylic acid before distillation process was low,which induced to large amount of wastewater and enormous energy consumption.In this work,a new method was proposed to concentrate the side stream of absorption column and thus increase the concentration in bottom product by electrodialysis.The influence of operating conditions on concentration rate and specific energy consumption were investigated by a laboratory-scale device.When the voltage drop was 1 V·cP^(-1)(1 cP=10^(-3) Pa·s),flow velocity was 3 cm·s^(-1) and the temperature was 35℃,the concentration rates of acrylic acid and acetic acid could be 203.3%and 156.6%in the continual-ED process.Based on the experimental data,the absorption process combined with ED was simulated,in which the diluted solution from ED process was used as spray water and the concentrated solution was feed back to the absorption column.The results shown that the flow rate of spray water was decreased by 37.1%,and the acrylic acid concentration at the bottom of the tower was increased by 4.56%.The ions exchange membranes before and after use 1200 h were tested by membrane surface morphology(scanning electron microscope),membrane chemical groups(infrared spectra),ion exchange capacity,and membrane area resistance,which indicated the membrane were stable in the acid system.This method provides new method for energy conservation and emission reduction in the traditional chemical industry.展开更多
This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L^-1（Na^＋）, on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At ...This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L^-1（Na^＋）, on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the optimum sodium ion concentration [1000-2000mg·L^-1（Na^＋）] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6-413.1mg·L^-1.h^-1, 28.04-28.97ml·g^-1, 7.52-7.83ml·g^-1.h^-1, respectively. The specific production yields of propionate, butyrate and valerate decreased with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g^-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.展开更多
This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na+), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the op...This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na+), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the opti- mum sodium ion concentration [1000—2000mg·L-1(Na+)] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6— 413.1mg·L-1·h-1, 28.04—28.97ml·g-1, 7.52—7.83ml·g-1·h-1, respectively. The specific production yields of propionate, butyrate and valerate decreased with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.展开更多
Formic acid(FA),which is obtainable through CO_(2)hydrogenation with green hydrogen or biomass conversion,has been used as a prospective liquid organic hydrogen carrier(LOHC)because of the abundant advantages of renew...Formic acid(FA),which is obtainable through CO_(2)hydrogenation with green hydrogen or biomass conversion,has been used as a prospective liquid organic hydrogen carrier(LOHC)because of the abundant advantages of renewability,wide availability,stability,and high volumetric capacity(53 g H_(2)/L).The development of highly efficient catalytic systems to achieve enhanced catalytic activity is attractive but still challenging.Herein,ultrafine and highly dispersed PdAu nanoclusters(NCs)anchored on amino-modified reduced graphene oxide(ArGO)were successfully synthesized via a facile impregnation-reduction method and applied as a catalyst toward formic acid dehydrogenation(FAD).Benefiting from the promoting effect of amino groups,the strain and ligand effect in the alloy,and the Mott–Schottky effect between PdAu NCs and ArGO,the resultant PdAu/ArGO affords an ultrahigh activity under visible light irradiation with an exceptional turnover frequency value of 10,699.5 h^(-1)at 298 K without any additives,more than 2.6times improvement than that under dark,which is the highest among all reported catalysts under the same conditions.This study provides a green and convenient strategy for developing more efficient and sustainable FAD catalysts and promotes the effective utilization of FA as a prospective renewable LOHC.展开更多
文摘Enhancing the separation efficiency of photogenerated carriers is propitious for the promotion of photocatalytic hydrogen production from formic acid decomposition.Herein,MoS2/Zn3In2S6(MoS2/ZIS6)composite photocatalysts containing varying mass percentages of MoS2 were obtained by a straightforward synthetic method.The results confirmed that MoS2,as a cocatalyst,markedly promoted the photogenerated charge separation efficiency and visible light-driven hydrogen production activity of ZIS6(λ>400 nm).Specifically,the as-prepared 0.5%MoS2/ZIS6 photocatalyst exhibited the highest photocatalytic hydrogen production rate(74.25μmol·h^-1),which was approximately 4.3 times higher than that of ZIS6(17.47μmol·h^-1).The excellent performance of the 0.5%MoS2/ZIS6 photocatalyst may be due to the fact that MoS2 has a low Fermi energy level and can thus enrich photogenerated electrons from ZIS6,and furthermore reduce H+derived from formic acid,to form hydrogen.The structure and morphology of the MoS2/ZIS6 photocatalysts and the reactive species were determined by X-ray diffraction,transmission electron microscopy,and field emission scanning electron microscopy,among others;a plausible mechanistic rationale is discussed based on the results.
基金financial support of grant from the Natural Science Funds for Young Scholar of China(Grant No.21107049)the priority academic program development of Jiangsu Higher Education Institution(PAPD).
文摘Hydrogen is recognized as a promising energy scours in the close future.Online hydrogen preparation from formic acid under mild reaction conditions causes extensive interests.Mo_(2)C and metal(Fe,Ni,Co,K)doped Mo_(2)C on granular activated carbon(GAC)were prepared and used as heterogeneous catalysts for H2 generation from formic acid on a fixed bed reactor at 100–250°C.The formic acid conversions on doped Mo_(2)C-Me/GAC are clearly improved,especially at lower reaction temperatures.Co doping presents outstanding effect on H2 selectivity and conversion rate compared to Ni and Fe.A 56.3%formic acid conversion was reached on Mo_(2)C-Co/GAC at 100°C,which triples that on Mo_(2)C/GAC at the same temperature.At 150°C,a high formic acid conversion over 90%was reached on Mo_(2)C-Co/GAC.These long lifetime catalysts with no precious metal provide a low cost route to hydrogen production from formic acid.
基金funded by the Natural Science Basic Research Program of Shaanxi(2021JCW-20)the Key Research and Development Program of Shaanxi(2020ZDLGY11-06)+1 种基金the Scientific Research Plan Projects of Shaanxi Education Department(20JS014)the Scientific Research Project of City-University Co-construction of Shaanxi Province(SXC-2108)。
文摘Formic acid(FA)has come to be considered a potential candidate for hydrogen storage,and the development of efficient catalysts for H2releasing is crucial for realizing the sustainable process from FA.Herein,we have developed the ultrafine Pd nanoparticle(NPs)with amine-functionalized carbon as a support,which was found to show an excellent catalytic activity in H_(2)generation from FA dehydrogenation.The synergetic mechanism between amine-group and Pd active site was demonstrated to facilitate H2generation byβ-hydride elimination.Moreover,the texture of support for Pd NPs also plays an important role in determining the reactivity of FA,since the diffusion of gaseous products makes the kinetics of diffusion as a challenge in this high performance Pd catalysts.As a result,the as-prepared Pd/NH_(2)-TPC catalyst with the small sized Pd nanoparticles and the hierarchically porous structures shows a turnover of frequency(TOF)value of 4312 h^(-1)for the additive-free FA dehydrogenation at room temperature,which is comparable to the most promising heterogeneous catalysts.Our results demonstrated that the intrinsic catalytic activities of active site as well as the porous structure of support are both important factors in determining catalytic performances in H2generation from FA dehydrogenation,which is also helpful to develop high-activity catalysts for other advanced gas-liquid-solid reactions systems.
基金supported by the National Key Research and Development Program of China(2016YFC0401202)Key Research and Development Program of Hebei Province(18394008D)。
文摘The absorption process in acrylic acid production was water-intensive.The concentration of acrylic acid before distillation process was low,which induced to large amount of wastewater and enormous energy consumption.In this work,a new method was proposed to concentrate the side stream of absorption column and thus increase the concentration in bottom product by electrodialysis.The influence of operating conditions on concentration rate and specific energy consumption were investigated by a laboratory-scale device.When the voltage drop was 1 V·cP^(-1)(1 cP=10^(-3) Pa·s),flow velocity was 3 cm·s^(-1) and the temperature was 35℃,the concentration rates of acrylic acid and acetic acid could be 203.3%and 156.6%in the continual-ED process.Based on the experimental data,the absorption process combined with ED was simulated,in which the diluted solution from ED process was used as spray water and the concentrated solution was feed back to the absorption column.The results shown that the flow rate of spray water was decreased by 37.1%,and the acrylic acid concentration at the bottom of the tower was increased by 4.56%.The ions exchange membranes before and after use 1200 h were tested by membrane surface morphology(scanning electron microscope),membrane chemical groups(infrared spectra),ion exchange capacity,and membrane area resistance,which indicated the membrane were stable in the acid system.This method provides new method for energy conservation and emission reduction in the traditional chemical industry.
基金Supported by the National Natural Science Foundation of China （No.20122203）.
文摘This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L^-1（Na^＋）, on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the optimum sodium ion concentration [1000-2000mg·L^-1（Na^＋）] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6-413.1mg·L^-1.h^-1, 28.04-28.97ml·g^-1, 7.52-7.83ml·g^-1.h^-1, respectively. The specific production yields of propionate, butyrate and valerate decreased with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g^-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.
基金Supported by the National Natural Science Foundation of China (No.20122203).
文摘This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na+), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the opti- mum sodium ion concentration [1000—2000mg·L-1(Na+)] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6— 413.1mg·L-1·h-1, 28.04—28.97ml·g-1, 7.52—7.83ml·g-1·h-1, respectively. The specific production yields of propionate, butyrate and valerate decreased with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.
基金financially supported by the National Natural Science Foundation of China(Nos.22162014 and 22162013)Department of Science and Technology of Jiangxi Province(Nos.20212ACB204009,20212BCJL23059 and 20232ACB214002)。
文摘Formic acid(FA),which is obtainable through CO_(2)hydrogenation with green hydrogen or biomass conversion,has been used as a prospective liquid organic hydrogen carrier(LOHC)because of the abundant advantages of renewability,wide availability,stability,and high volumetric capacity(53 g H_(2)/L).The development of highly efficient catalytic systems to achieve enhanced catalytic activity is attractive but still challenging.Herein,ultrafine and highly dispersed PdAu nanoclusters(NCs)anchored on amino-modified reduced graphene oxide(ArGO)were successfully synthesized via a facile impregnation-reduction method and applied as a catalyst toward formic acid dehydrogenation(FAD).Benefiting from the promoting effect of amino groups,the strain and ligand effect in the alloy,and the Mott–Schottky effect between PdAu NCs and ArGO,the resultant PdAu/ArGO affords an ultrahigh activity under visible light irradiation with an exceptional turnover frequency value of 10,699.5 h^(-1)at 298 K without any additives,more than 2.6times improvement than that under dark,which is the highest among all reported catalysts under the same conditions.This study provides a green and convenient strategy for developing more efficient and sustainable FAD catalysts and promotes the effective utilization of FA as a prospective renewable LOHC.
