Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin f...Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.展开更多
Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dyn...Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dynamic changes in soil communities,potential bacterial pathogens,and ARG profiles under various organicmaterial treatments during RSD,including distillers’grains,potato peel,peanut vine,and peanut vine combined with charcoal.Results revealed that applying diverse organic materials in RSD significantly altered bacterial community composition and diminished the relative abundance of potential bacterial pathogens(P<0.05).The relative abundance of high-risk ARGs decreased by 10.7%-30.6%after RSD treatments,the main decreased ARG subtypeswere AAC(3)_Via,dfrA1,ErmB,lnuB,aadA.Actinobacteria was the primary host of ARGs and was suppressed by RSD.Soil physicochemical properties,such as total nitrogen,soil pH,total carbon,were crucial factors affecting ARG profiles.Our findings demonstrated that RSD treatment inhibited pathogenic bacteria and could be an option for reducing high-risk ARG proliferation in soil.展开更多
An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The r...An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The reductive hydroarylation of acrylates with aryl halides was successfully achieved without requiring exogenous photoredox catalysts.This reaction is highlighted by the simple and mild conditions,good functional group tolerance,thus providing a complementary approach for alkenes reductive Heck reaction.展开更多
Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of...Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of polyfluoroarenes with alkyl halides under mild conditions is reported.Polyfluoroarenes(3~6 F)can reacted smoothly with a diverse range of alkyl halides,such as primary,secondary,and tertiary alkyl iodides.The efficient formation of C(sp2)—C(sp3)can be achieved through the combination of Ni catalysis and(Bpin)2/K2CO3 as terminal reductant.展开更多
The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the ef...The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the efficacy of carbon dioxide radical anion(CO_(2)·^(-))mediated advanced reduction processes(ARPs)for the reductive dechlorination of chlorinated alkanes using small molecular monocarboxylic acids(SMAs)under UV irradiation.The study focused on formic acid(HCOOH),acetic acid(CH_3COOH),and propionic acid(CH_3CH_(2)COOH)to generate CO_(2)·^(-),revealing that UV/HCOOH system exhibits a notably high chloroform(CF)degradation efficiency of 97.8%in 90 min.Kinetic studies indicated a linear relationship between the HCOOH concentrations and the observed reaction rate constants(k_(obs)),demonstrating that CO_(2)·^(-)production is crucial for CF degradation.Electron paramagnetic resonance spectroscopy identified CO_(2)·^(-)and hydroxyl radicals(HO·)as the active species,with the former playing a predominant role in CF degradation.The study also explored the influence of carbon chain length in SMAs on CF degradation,finding that longer chains decrease the degradation efficiency,potentially due to reduced UV activation.A higher reaction rate constant(k_(obs))under acidic conditions,with a marked decrease in efficiency as the pH exceeds 3.7,where HCOO^(-)becomes predominant.This study enhances our understanding of CO_(2)·^(-)mediated ARPs and explores potential applications in environmental remediation,providing insights into the pathways and mechanisms of CF degradation.The UV/SMAs systems offer advantages for practical applications,such as milder reaction conditions and higher efficiency compared to traditional methods.展开更多
The thermal effects,spontaneity and proceeding degree of 32 chemical reactions during coal reductive decomposition phosphogypsum(PG)to prepare CaO and SO_(2)are analyzed utilizing thermodynamic theory and method.The i...The thermal effects,spontaneity and proceeding degree of 32 chemical reactions during coal reductive decomposition phosphogypsum(PG)to prepare CaO and SO_(2)are analyzed utilizing thermodynamic theory and method.The ideal reaction temperature for PG decomposition and desulfurization is 1173-1273 K.The 10 key chemical reactions controlling coal reductive decomposition PG have been selected.The heat release of critical exothermic reactions can satisfy the autothermal operation of PG decomposition and desulfurization process.Meanwhile,the spontaneity of oxidation reactions has thermodynamically priority over reduction reactions.But the reaction mechanism shows that the oxidation of CaS by O_(2)is in parallel competition with the reduction of CaSO_(4)by CO and C.Furthermore,clarifying the regulatory mechanisms of PG decomposition temperature and reaction atmosphere(reducibility and oxidation)is beneficial for maximizing the production of CaO and SO_(2).展开更多
Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petro...Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petroleum,while harsh or toxic conditions are often needed.Biomass is abundant and renewable,which serves as a promising alternative raw material to produce primary diamines.This review primarily focuses on the synthesis of 2,5-bis(aminomethyl)furan(BAMF),a bio-based diamine with potential as a biomonomer for polyamides and polyureas.Specifically,this review emphasizes the synthesis of BAMF fromthree biomass-derived alcohols and aldehydes,namely 5-hydroxymethylfurfural(HMF),2,5-bis(hydroxymethyl)furan(BHMF),and 2,5-diformylfuran(DFF).These are the key substrates to get BAMF and could be readily obtained from carbohydrates.Even though great effort has been put into the synthesis of BAMF,it remains a tough problem to obtain BAMF with a high yield at a low cost due to the inevitable side reactions,such as unwanted hydrogenation reactions and condensation reactions.Many strategies have been proposed to solve this problem,such as the hydrogen-borrowing strategy and stepwise reductive amination strategy.Herein,we will summarize the key advancements in this area,and discuss the challenges that need to be responded in the future,hoping to provide an insight into the design and development of a more efficient system for the production of biomass-derived diamines.展开更多
Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon bonds.Herein,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp...Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon bonds.Herein,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds.This presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)halides.This presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.展开更多
Aromatic aldehydes are the most fundamentally important compounds used in organic synthesis.The development of new synthetic methods for introduction of a formyl group into an organic scaffold is highly desirable.In t...Aromatic aldehydes are the most fundamentally important compounds used in organic synthesis.The development of new synthetic methods for introduction of a formyl group into an organic scaffold is highly desirable.In this report,a nickel-catalyzed reductive coupling between aryl halides andα–chloro N-methoxyphthalimide has been documented for the synthesis of a diverse array of aromatic aldehydes.Because of mild reductive coupling conditions,excellent functional group tolerance,especially for substrates containing free-OH and-NH_(2),was observed.Due to the simple operation mode,a large library of aromatic aldehydes can be quickly constructed by this process.Moreover,the present protocol is amenable for late-stage functionalization of bioactive compound.A combined computational and experimental investigation suggested the reaction may undergo a reaction mechanism of active Ni(I)catalyst formation and the formation of key formyl radical intermediate under zinc reductive conditions.展开更多
Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device perform...Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device performance and reproducibility.Here,we utilize a reductive natural amino acid,Nacetylcysteine(NALC),to stabilize the precursor solution for printable carbon-based hole-conductorfree mesoscopic perovskite solar cells.We find that I_(2) can be generated in the aged solution containing methylammonium iodide(MI) in an inert atmosphere and speed up the MA-FA^(+)(formamidinium) reaction which produces large-size cations and hinders the formation of perovskite phase.NALC effectively stabilizes the precursor via its sulfhydryl group which reduces I_(2) back to I^(-)and provides H^(+).The NALC-stabilized precursor which is aged for 1440 h leads to devices with a power conversion efficiency equivalent to 98% of that for devices prepared with the fresh precursor.Furthermore,NALC improves the device power conversion efficiency from 16.16% to 18.41% along with enhanced stability under atmospheric conditions by modifying grain boundaries in perovskite films and reducing associated defects.展开更多
Developing applicable methods to forge linkages between sp^(3)and sp^(2)-hydridized carbons is of great significance in drug discovery.We show here a new,Ni-catalyzed reductive cross-coupling reaction that forms Csp^(...Developing applicable methods to forge linkages between sp^(3)and sp^(2)-hydridized carbons is of great significance in drug discovery.We show here a new,Ni-catalyzed reductive cross-coupling reaction that forms Csp^(3)-Csp^(2)bonds from aryl iodides and cyclic sulfonium salts.Notably,Csp^(3)-Csp^(2)bonds can be forged selectively at the iodine-bearing carbon of bromo(iodo)arenes which is usually recognized as a huge challenge under the catalytic reductive cross-coupling(CRCC)conditions.Experimental and computational mechanistic studies support LNi~IAr as an active species,while the untraditional anti-Markovnikov selective alkylation of asymmetric sulfonium salts is determined by the oxidative S-substitution of sulfonium salts with LNi~IAr.This protocol further expands the range of alkyl electrophiles under the CRCC conditions and provides a new strategy for the construction of Csp^(3)-Csp^(2)bonds.展开更多
Zinc ferrite is the principal constituent in zinc neutral-leach residue（NLR） which is commonly treated by hot-acid leaching in electrolytic zinc plants. Reductive leaching of zinc ferrite with sphalerite concentrate...Zinc ferrite is the principal constituent in zinc neutral-leach residue（NLR） which is commonly treated by hot-acid leaching in electrolytic zinc plants. Reductive leaching of zinc ferrite with sphalerite concentrate as a reducing agent was performed. It was found that leaching of zinc ferrite in the presence of sphalerit concentrate was a viable process that effectively extracted zinc and indium and converted Fe^3＋ into Fe^2＋ at the same time. Reflux leaching tests by two stages were performed to achieve extractions of 98.1% for zinc and 97.5% for indium, and a Fe^2＋/Fe^3＋ molar ratio of 9.6 in leach solution was also obtained. The leaching behaviors of other elements, such as iron, copper and tin were also studied. The results showed that iron and copper were completely leached, whereas tin presented lower extraction values.展开更多
A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%,...A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%, 96.7% and 92.6% after grinding for 4, 6, 1 and 1 h, respectively. Based on the chemical phase composition analysis and morphological characteristics of sulfidized products by XRD, SEM and TEM, a possible reaction mechanism, mechanically induced self-propagating reaction （MSR）, was proposed to explain the sulfidization reaction. In addition, the floatability of sulfidized products was investigated for the recovery of metal sulfide and ZnS can be concentrated with a high concentration ratio and concentrate grade. By using the sulfidizing process, it is expected that the recovery of zinc from the wastes or purification of heavy-metal-containing hazardous residues is technically feasible.展开更多
Pure compounds and kaolin were employed to investigate the reaction behavior of ferric oxide in thetrinarysystem Fe2O3?SiO2?Al2O3 during reductive sintering process. The thermodynamic analyses and reductive sintering ...Pure compounds and kaolin were employed to investigate the reaction behavior of ferric oxide in thetrinarysystem Fe2O3?SiO2?Al2O3 during reductive sintering process. The thermodynamic analyses and reductive sintering experimental results show that ferrous oxide generated from the reduction of ferric oxide by carbon can react with silicon dioxide and aluminum oxide to form ferrous silicate and hercynite at 1173 K, respectively. In the trinary system Fe2O3?SiO2?Al2O3, ferrous oxide obtained from ferric oxide reduction preferentially reacts with aluminum oxide to form hercynite, and the reaction of ferrous oxide with silicon dioxide occurs only when there is surplus ferrous oxide after the exhaustion of aluminum oxide. When sintering temperature rises to 1473 K, hercynite further reacts with silicon dioxide to form mullite and ferrous oxide. Results presented in this work may throw a new light upon the separation of alumina and silica present in Al/Fe-bearing materials with low mass ratio of alumina to silica in alumina production.展开更多
Zinc neutral leaching residue（ZNLR） from hydrometallurgical zinc smelting processing can be determined as hazardous intermediate containing considerable amounts of Cd and Zn which have great threats to the environme...Zinc neutral leaching residue（ZNLR） from hydrometallurgical zinc smelting processing can be determined as hazardous intermediate containing considerable amounts of Cd and Zn which have great threats to the environment. The ZNLR contained approximately 35.99% Zn, 15.93% Fe and 0.26% Cd, and Cd mainly existed as ferrites in the ZNLR in this research. Reductive acid leaching of ZNLR was investigated. The effects of hydrazine sulfate concentration, initial sulfuric acid concentration, temperature, duration and liquid-to-solid ratio on the extraction of Cd, Zn and Fe were examined. The extraction efficiencies of Cd, Zn and Fe reached 90.81%, 95.83% and 94.19%, respectively when the leaching parameters were fixed as follows： hydrazine sulfate concentration, 33.3 g/L; sulfuric acid concentration, 80 g/L; temperature, 95 °C; duration of leaching, 120 min; liquid-to-solid ratio, 10 m L/g and agitation, 400 r/min. XRD and SEM-EDS analyses of the leaching residue confirmed that lead sulfate（Pb SO4） and hydrazinium zinc sulfate（（N2H5）2Zn（SO4）2） were the main phases remaining in the reductive leaching residue.展开更多
Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching t...Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching temperature and reaction time on leaching process were explored. The leaching efficiency of Gabonese manganese oxide ore reached almost 100% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 2.5 molFL, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching efficiency of Xiangxi manganese oxide ore reached 99.8% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 1.7 mol/L, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching process followed the internal diffusion controlled kinetic model, and the apparent activation energies of Gabonese manganese oxide ore and Xiangxi manganese oxide ore were calculated to be 38.2 kJ/mol and 20.4 kJ/mol, respectively. The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of XRD analysis and SEM analysis.展开更多
The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the e...The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2 SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol –1 . The experimental results indicate a reaction order of 0.52 for H2SO4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.展开更多
Hydrazine sulfate was used as a reducing agent for the leaching of Li,Ni,Co and Mn from spent lithium-ion batteries.The effects of the reaction conditions on the leaching mechanism and kinetics were characterized and ...Hydrazine sulfate was used as a reducing agent for the leaching of Li,Ni,Co and Mn from spent lithium-ion batteries.The effects of the reaction conditions on the leaching mechanism and kinetics were characterized and examined.97%of the available Li,96%of the available Ni,95%of the available Co,and 86%of the available Mn are extracted under the following optimized conditions:sulfuric acid concentration of 2.0 mol/L,hydrazine sulfate dosage of 30 g/L,solid-to-liquid ratio of 50 g/L,temperature of 80℃,and leaching time of 60 min.The activation energies of the leaching are determined to be 44.32,59.37 and 55.62 k J/mol for Li,Ni and Co,respectively.By performing X-ray diffraction and scanning electron microscopy in conjunction with energy dispersive X-ray spectroscopy,it is confirmed that the main phase in the leaching residue is MnO2.The results show that hydrazine sulfate is an effective reducing agent in the acid leaching process for spent lithium-ion batteries.展开更多
Sulfur hexafluoride （SF6） is known as one of the most powerful greenhouse gases in the atmosphere. Reductive photodegradation of SF6 by styrene has been studied with the purpose of developing a novel remediation for...Sulfur hexafluoride （SF6） is known as one of the most powerful greenhouse gases in the atmosphere. Reductive photodegradation of SF6 by styrene has been studied with the purpose of developing a novel remediation for sulfur hexafluoride pollution. Effects of reaction conditions on the destruction and removal efficiency （DRE） of SF6 are examined in this study. Both initial styrene-to-SF6 ratio and initial oxygen concentration exert a significant influence on DRE. SF6 removal efficiency reaches a maximum value at the initial styrene-to-SF6 ratio of 0.2. It is found that DRE increases with oxygen concentration over the range of 0 to 0.09 mol/m^3 and then decreases with increasing oxygen concentration. When water vapor is fed into the gas mixture, DRE is slightly enhanced over the whole studied time scale. The X-ray Photoelectron Spectroscopy （XPS） analysis, together with gas chromatography-mass spectrometry （GC-MS） and Fourier Transform Infrared spectroscopy （FT-IR） analysis, prove that nearly all the initial fluorine residing in the gas phase is in the form of SiF4, whereas, the initial sulfur is deposited in the form of elemental sulfur, after photodegradation. Free from toxic byproducts, photodegradation in the presence of styrene may serve as a promising technique for SF6 abatement.展开更多
The kinetics of reductive leaching of manganese from a low-grade manganese oxide ore were studied using cellulose as reductant in dilute sulfuric acid medium.It was found that when the stirring speed was higher than 2...The kinetics of reductive leaching of manganese from a low-grade manganese oxide ore were studied using cellulose as reductant in dilute sulfuric acid medium.It was found that when the stirring speed was higher than 200 r/min,the effect of gas film diffusion on manganese extraction efficiency could be neglected,and the kinetic behavior was investigated under the condition of elimination of external diffusion influence on the leaching process.Effects of leaching temperature,mass ratio of cellulose and ore,and the sulfuric acid concentration on manganese extraction efficiency were discussed.The kinetic data were analyzed based on the shrinking core model,which indicated that the leaching process was dominated by both ash layer diffusion and chemical reaction at the initial stage,with the progress of leaching reaction,the rate-controlling step switched to the ash layer diffusion.It was also concluded that the sulfuric acid concentration had the most significant influence on the leaching rate,the reaction orders with respect to the sulfuric acid concentration were 2.102 in the first 60 min,and 3.642 in the later 90 min,while the reaction orders for mass ratio of cellulose and ore were 0.660 and 0.724,respectively.An Arrhenius relationship was used to relate the temperature to the rate of leaching,from which apparent activation energies were calculated to be 46.487 kJ/mol and 62.290 kJ/mol at the two stages,respectively.Finally,the overall leaching rate equations for the manganese dissolution reaction with cellulose in sulphuric acid solution were developed.The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of SEM and XRD analyses.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(QNTD202302)National Natural Science Foundation of China(22378024)the Foreign expert program(G2022109001L).
文摘Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent years.Herein,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps process.The key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene glycol.The utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling up.In the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.
基金supported by the Key Research and Development Program of Shandong Province,China(No 2021CXGC010803)Pan’an County Chinese Medicine Industry Project(No.PZYF202103).
文摘Reductive soil disinfestation(RSD)is commonly employed for soil remediation in greenhouse cultivation.However,its influence on antibiotic resistance genes(ARGs)in soil remains uncertain.This study investigated the dynamic changes in soil communities,potential bacterial pathogens,and ARG profiles under various organicmaterial treatments during RSD,including distillers’grains,potato peel,peanut vine,and peanut vine combined with charcoal.Results revealed that applying diverse organic materials in RSD significantly altered bacterial community composition and diminished the relative abundance of potential bacterial pathogens(P<0.05).The relative abundance of high-risk ARGs decreased by 10.7%-30.6%after RSD treatments,the main decreased ARG subtypeswere AAC(3)_Via,dfrA1,ErmB,lnuB,aadA.Actinobacteria was the primary host of ARGs and was suppressed by RSD.Soil physicochemical properties,such as total nitrogen,soil pH,total carbon,were crucial factors affecting ARG profiles.Our findings demonstrated that RSD treatment inhibited pathogenic bacteria and could be an option for reducing high-risk ARG proliferation in soil.
文摘An efficient visible-light induced nickel-catalyzed reductive Heck reaction of alkenes by using mild organic reductant Hantzsch ester(HEH)instead of traditional metal reductants or hydride reagents was developed.The reductive hydroarylation of acrylates with aryl halides was successfully achieved without requiring exogenous photoredox catalysts.This reaction is highlighted by the simple and mild conditions,good functional group tolerance,thus providing a complementary approach for alkenes reductive Heck reaction.
文摘Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of polyfluoroarenes with alkyl halides under mild conditions is reported.Polyfluoroarenes(3~6 F)can reacted smoothly with a diverse range of alkyl halides,such as primary,secondary,and tertiary alkyl iodides.The efficient formation of C(sp2)—C(sp3)can be achieved through the combination of Ni catalysis and(Bpin)2/K2CO3 as terminal reductant.
基金supported by the National Natural Science Foundation of China(Nos.52270165 and 51978537)the Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province。
文摘The persistence of chlorinated alkanes in aquatic environments poses significant health risks due to its biotoxicity and high volatility,which contributes to both water and air pollution.This study investigates the efficacy of carbon dioxide radical anion(CO_(2)·^(-))mediated advanced reduction processes(ARPs)for the reductive dechlorination of chlorinated alkanes using small molecular monocarboxylic acids(SMAs)under UV irradiation.The study focused on formic acid(HCOOH),acetic acid(CH_3COOH),and propionic acid(CH_3CH_(2)COOH)to generate CO_(2)·^(-),revealing that UV/HCOOH system exhibits a notably high chloroform(CF)degradation efficiency of 97.8%in 90 min.Kinetic studies indicated a linear relationship between the HCOOH concentrations and the observed reaction rate constants(k_(obs)),demonstrating that CO_(2)·^(-)production is crucial for CF degradation.Electron paramagnetic resonance spectroscopy identified CO_(2)·^(-)and hydroxyl radicals(HO·)as the active species,with the former playing a predominant role in CF degradation.The study also explored the influence of carbon chain length in SMAs on CF degradation,finding that longer chains decrease the degradation efficiency,potentially due to reduced UV activation.A higher reaction rate constant(k_(obs))under acidic conditions,with a marked decrease in efficiency as the pH exceeds 3.7,where HCOO^(-)becomes predominant.This study enhances our understanding of CO_(2)·^(-)mediated ARPs and explores potential applications in environmental remediation,providing insights into the pathways and mechanisms of CF degradation.The UV/SMAs systems offer advantages for practical applications,such as milder reaction conditions and higher efficiency compared to traditional methods.
基金financial support by the Phosphogypsum Low-Temperature Decomposition to Produce Calcium-Based Materials and Sulfuric Acid Raw Gas Technology(Horizontal Project)(8503009049)National Natural Science Foundation of China(52376101).
文摘The thermal effects,spontaneity and proceeding degree of 32 chemical reactions during coal reductive decomposition phosphogypsum(PG)to prepare CaO and SO_(2)are analyzed utilizing thermodynamic theory and method.The ideal reaction temperature for PG decomposition and desulfurization is 1173-1273 K.The 10 key chemical reactions controlling coal reductive decomposition PG have been selected.The heat release of critical exothermic reactions can satisfy the autothermal operation of PG decomposition and desulfurization process.Meanwhile,the spontaneity of oxidation reactions has thermodynamically priority over reduction reactions.But the reaction mechanism shows that the oxidation of CaS by O_(2)is in parallel competition with the reduction of CaSO_(4)by CO and C.Furthermore,clarifying the regulatory mechanisms of PG decomposition temperature and reaction atmosphere(reducibility and oxidation)is beneficial for maximizing the production of CaO and SO_(2).
基金financially supported by China Scholarship Council,Science and Technology Project of the State Administration for Market Regulation(2022MK111)the Fundamental Research Funds for the Central Universities.
文摘Primary diamines play an important role in the chemical industry,where they are widely used as raw materials for the manufacture of pharmaceuticals and polymers.Currently,primary diamines are mainly derived from petroleum,while harsh or toxic conditions are often needed.Biomass is abundant and renewable,which serves as a promising alternative raw material to produce primary diamines.This review primarily focuses on the synthesis of 2,5-bis(aminomethyl)furan(BAMF),a bio-based diamine with potential as a biomonomer for polyamides and polyureas.Specifically,this review emphasizes the synthesis of BAMF fromthree biomass-derived alcohols and aldehydes,namely 5-hydroxymethylfurfural(HMF),2,5-bis(hydroxymethyl)furan(BHMF),and 2,5-diformylfuran(DFF).These are the key substrates to get BAMF and could be readily obtained from carbohydrates.Even though great effort has been put into the synthesis of BAMF,it remains a tough problem to obtain BAMF with a high yield at a low cost due to the inevitable side reactions,such as unwanted hydrogenation reactions and condensation reactions.Many strategies have been proposed to solve this problem,such as the hydrogen-borrowing strategy and stepwise reductive amination strategy.Herein,we will summarize the key advancements in this area,and discuss the challenges that need to be responded in the future,hoping to provide an insight into the design and development of a more efficient system for the production of biomass-derived diamines.
基金the National Natural Science Foundation of China(Nos.22371273,22293011 and T2341001)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2023476)the National Science Foundation of Anhui Province(No.2208085J26)。
文摘Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon bonds.Herein,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds.This presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)halides.This presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.
基金financial support from the National Natural Science Foundation of China(No.22001147)Taishan Scholars Project of Shandong Province(No.tsqn202103027)+1 种基金Distinguished Young Scholars of Shandong Province(Overseas)(No.2022HWYQ-001)Qilu Youth Scholar Funding of Shandong University。
文摘Aromatic aldehydes are the most fundamentally important compounds used in organic synthesis.The development of new synthetic methods for introduction of a formyl group into an organic scaffold is highly desirable.In this report,a nickel-catalyzed reductive coupling between aryl halides andα–chloro N-methoxyphthalimide has been documented for the synthesis of a diverse array of aromatic aldehydes.Because of mild reductive coupling conditions,excellent functional group tolerance,especially for substrates containing free-OH and-NH_(2),was observed.Due to the simple operation mode,a large library of aromatic aldehydes can be quickly constructed by this process.Moreover,the present protocol is amenable for late-stage functionalization of bioactive compound.A combined computational and experimental investigation suggested the reaction may undergo a reaction mechanism of active Ni(I)catalyst formation and the formation of key formyl radical intermediate under zinc reductive conditions.
基金financial support from the National Natural Science Foundation of China(grant nos.52172198,51902117,and 91733301)。
文摘Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device performance and reproducibility.Here,we utilize a reductive natural amino acid,Nacetylcysteine(NALC),to stabilize the precursor solution for printable carbon-based hole-conductorfree mesoscopic perovskite solar cells.We find that I_(2) can be generated in the aged solution containing methylammonium iodide(MI) in an inert atmosphere and speed up the MA-FA^(+)(formamidinium) reaction which produces large-size cations and hinders the formation of perovskite phase.NALC effectively stabilizes the precursor via its sulfhydryl group which reduces I_(2) back to I^(-)and provides H^(+).The NALC-stabilized precursor which is aged for 1440 h leads to devices with a power conversion efficiency equivalent to 98% of that for devices prepared with the fresh precursor.Furthermore,NALC improves the device power conversion efficiency from 16.16% to 18.41% along with enhanced stability under atmospheric conditions by modifying grain boundaries in perovskite films and reducing associated defects.
基金supported by the National Natural Science Foundation of China(No.22271170)the Scientific Research Foundation of Qingdao University of Science and Technology。
文摘Developing applicable methods to forge linkages between sp^(3)and sp^(2)-hydridized carbons is of great significance in drug discovery.We show here a new,Ni-catalyzed reductive cross-coupling reaction that forms Csp^(3)-Csp^(2)bonds from aryl iodides and cyclic sulfonium salts.Notably,Csp^(3)-Csp^(2)bonds can be forged selectively at the iodine-bearing carbon of bromo(iodo)arenes which is usually recognized as a huge challenge under the catalytic reductive cross-coupling(CRCC)conditions.Experimental and computational mechanistic studies support LNi~IAr as an active species,while the untraditional anti-Markovnikov selective alkylation of asymmetric sulfonium salts is determined by the oxidative S-substitution of sulfonium salts with LNi~IAr.This protocol further expands the range of alkyl electrophiles under the CRCC conditions and provides a new strategy for the construction of Csp^(3)-Csp^(2)bonds.
基金Project(2014CB643404)supported by the National Basic Research Program of ChinaProjects(51564030,51474117,51304093,51364022)supported by the National Natural Science Foundation of China+1 种基金Project(0120150070)supported by Yunnan Applied Basic Reach Project,ChinaProject(ZD2014003)supported by the Education Department of Yunnan Province,China
文摘Zinc ferrite is the principal constituent in zinc neutral-leach residue（NLR） which is commonly treated by hot-acid leaching in electrolytic zinc plants. Reductive leaching of zinc ferrite with sphalerite concentrate as a reducing agent was performed. It was found that leaching of zinc ferrite in the presence of sphalerit concentrate was a viable process that effectively extracted zinc and indium and converted Fe^3＋ into Fe^2＋ at the same time. Reflux leaching tests by two stages were performed to achieve extractions of 98.1% for zinc and 97.5% for indium, and a Fe^2＋/Fe^3＋ molar ratio of 9.6 in leach solution was also obtained. The leaching behaviors of other elements, such as iron, copper and tin were also studied. The results showed that iron and copper were completely leached, whereas tin presented lower extraction values.
基金Project(50925417) supported by the China National Funds for Distinguished Young ScientistsProject(50830301) supported by the National Natural Science Foundation of China+1 种基金Projects(2010AA065203,2011AA061001) supported by the National High-tech Research Program of ChinaProject(NCET-10-0840) supported by the Program for New Century Excellent Talents in University,China
文摘A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%, 96.7% and 92.6% after grinding for 4, 6, 1 and 1 h, respectively. Based on the chemical phase composition analysis and morphological characteristics of sulfidized products by XRD, SEM and TEM, a possible reaction mechanism, mechanically induced self-propagating reaction （MSR）, was proposed to explain the sulfidization reaction. In addition, the floatability of sulfidized products was investigated for the recovery of metal sulfide and ZnS can be concentrated with a high concentration ratio and concentrate grade. By using the sulfidizing process, it is expected that the recovery of zinc from the wastes or purification of heavy-metal-containing hazardous residues is technically feasible.
基金Project(51274243)supported by the National Natural Science Foundation of China
文摘Pure compounds and kaolin were employed to investigate the reaction behavior of ferric oxide in thetrinarysystem Fe2O3?SiO2?Al2O3 during reductive sintering process. The thermodynamic analyses and reductive sintering experimental results show that ferrous oxide generated from the reduction of ferric oxide by carbon can react with silicon dioxide and aluminum oxide to form ferrous silicate and hercynite at 1173 K, respectively. In the trinary system Fe2O3?SiO2?Al2O3, ferrous oxide obtained from ferric oxide reduction preferentially reacts with aluminum oxide to form hercynite, and the reaction of ferrous oxide with silicon dioxide occurs only when there is surplus ferrous oxide after the exhaustion of aluminum oxide. When sintering temperature rises to 1473 K, hercynite further reacts with silicon dioxide to form mullite and ferrous oxide. Results presented in this work may throw a new light upon the separation of alumina and silica present in Al/Fe-bearing materials with low mass ratio of alumina to silica in alumina production.
基金Project(2012FJ1010)supported by the Key Project of Science and Technology of Hunan ProvinceChina+2 种基金Project(51474247)supported by the National Natural Science Foundation of ChinaProject(2012GS430201)supported by the Science and Technology Program for Public WellbeingChina
文摘Zinc neutral leaching residue（ZNLR） from hydrometallurgical zinc smelting processing can be determined as hazardous intermediate containing considerable amounts of Cd and Zn which have great threats to the environment. The ZNLR contained approximately 35.99% Zn, 15.93% Fe and 0.26% Cd, and Cd mainly existed as ferrites in the ZNLR in this research. Reductive acid leaching of ZNLR was investigated. The effects of hydrazine sulfate concentration, initial sulfuric acid concentration, temperature, duration and liquid-to-solid ratio on the extraction of Cd, Zn and Fe were examined. The extraction efficiencies of Cd, Zn and Fe reached 90.81%, 95.83% and 94.19%, respectively when the leaching parameters were fixed as follows： hydrazine sulfate concentration, 33.3 g/L; sulfuric acid concentration, 80 g/L; temperature, 95 °C; duration of leaching, 120 min; liquid-to-solid ratio, 10 m L/g and agitation, 400 r/min. XRD and SEM-EDS analyses of the leaching residue confirmed that lead sulfate（Pb SO4） and hydrazinium zinc sulfate（（N2H5）2Zn（SO4）2） were the main phases remaining in the reductive leaching residue.
基金Project(2010FJ1011)supported by the Major Project of Hunan Science and Technology,ChinaProject(cstc2012ggB90002)supported by the Chongqing Key Science and Technology Program,China
文摘Manganese oxide ores from Gabon and Xiangxi were leached with waste tea as reductant in dilute sulfuric acid solution. The effects of waste tea dosage, concentration of sulfuric acid, liquid-to-solid ratio, leaching temperature and reaction time on leaching process were explored. The leaching efficiency of Gabonese manganese oxide ore reached almost 100% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 2.5 molFL, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching efficiency of Xiangxi manganese oxide ore reached 99.8% under the optimal condition which was determined as follows： manganese oxide ore to waste tea mass ratio of 10：1, sulfuric acid concentration of 1.7 mol/L, liquid-to-solid ratio of 7.5：1, leaching temperature of 368 K, time of 8 h. The leaching process followed the internal diffusion controlled kinetic model, and the apparent activation energies of Gabonese manganese oxide ore and Xiangxi manganese oxide ore were calculated to be 38.2 kJ/mol and 20.4 kJ/mol, respectively. The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of XRD analysis and SEM analysis.
基金Supported by the National Natural Science Foundation of China （20866001） the Natural Science Foundation of GuangxiProvince （0832035）
文摘The kinetics of reductive leaching of manganese from low grade pyrolusite in dilute sulfuric acid in the presence of molasses alcohol wastewater was investigated. The shrinking core model was applied to quantify the effects of reaction parameters on leaching rate. The leaching rate increases with reaction temperature, concentrations of H 2 SO 4 and organic matter in molasses alcohol wastewater increase and ore particle size decreases. The leaching process follows the kinetics of a shrinking core model and the apparent activation energy is 57.5 kJ·mol –1 . The experimental results indicate a reaction order of 0.52 for H2SO4 concentration and 0.90 for chemical oxygen demand (COD) of molasses alcohol wastewater. It is concluded that the reductive leaching of pyrolusite with molasses alcohol wastewater is controlled by the diffusion through the ash/inert layer composed of the associated minerals.
基金Project(51674298)supported by the National Natural Science Foundation of ChinaProject supported by Anhui Province Research and Development Innovation Program,China。
文摘Hydrazine sulfate was used as a reducing agent for the leaching of Li,Ni,Co and Mn from spent lithium-ion batteries.The effects of the reaction conditions on the leaching mechanism and kinetics were characterized and examined.97%of the available Li,96%of the available Ni,95%of the available Co,and 86%of the available Mn are extracted under the following optimized conditions:sulfuric acid concentration of 2.0 mol/L,hydrazine sulfate dosage of 30 g/L,solid-to-liquid ratio of 50 g/L,temperature of 80℃,and leaching time of 60 min.The activation energies of the leaching are determined to be 44.32,59.37 and 55.62 k J/mol for Li,Ni and Co,respectively.By performing X-ray diffraction and scanning electron microscopy in conjunction with energy dispersive X-ray spectroscopy,it is confirmed that the main phase in the leaching residue is MnO2.The results show that hydrazine sulfate is an effective reducing agent in the acid leaching process for spent lithium-ion batteries.
基金This work was supported by the National Natural Science Foundation of China （No. 20177004, 20507004）.
文摘Sulfur hexafluoride （SF6） is known as one of the most powerful greenhouse gases in the atmosphere. Reductive photodegradation of SF6 by styrene has been studied with the purpose of developing a novel remediation for sulfur hexafluoride pollution. Effects of reaction conditions on the destruction and removal efficiency （DRE） of SF6 are examined in this study. Both initial styrene-to-SF6 ratio and initial oxygen concentration exert a significant influence on DRE. SF6 removal efficiency reaches a maximum value at the initial styrene-to-SF6 ratio of 0.2. It is found that DRE increases with oxygen concentration over the range of 0 to 0.09 mol/m^3 and then decreases with increasing oxygen concentration. When water vapor is fed into the gas mixture, DRE is slightly enhanced over the whole studied time scale. The X-ray Photoelectron Spectroscopy （XPS） analysis, together with gas chromatography-mass spectrometry （GC-MS） and Fourier Transform Infrared spectroscopy （FT-IR） analysis, prove that nearly all the initial fluorine residing in the gas phase is in the form of SiF4, whereas, the initial sulfur is deposited in the form of elemental sulfur, after photodegradation. Free from toxic byproducts, photodegradation in the presence of styrene may serve as a promising technique for SF6 abatement.
基金Project(2010FJ1011)supported by the Major Project of Science and Technology of Hunan Province,China
文摘The kinetics of reductive leaching of manganese from a low-grade manganese oxide ore were studied using cellulose as reductant in dilute sulfuric acid medium.It was found that when the stirring speed was higher than 200 r/min,the effect of gas film diffusion on manganese extraction efficiency could be neglected,and the kinetic behavior was investigated under the condition of elimination of external diffusion influence on the leaching process.Effects of leaching temperature,mass ratio of cellulose and ore,and the sulfuric acid concentration on manganese extraction efficiency were discussed.The kinetic data were analyzed based on the shrinking core model,which indicated that the leaching process was dominated by both ash layer diffusion and chemical reaction at the initial stage,with the progress of leaching reaction,the rate-controlling step switched to the ash layer diffusion.It was also concluded that the sulfuric acid concentration had the most significant influence on the leaching rate,the reaction orders with respect to the sulfuric acid concentration were 2.102 in the first 60 min,and 3.642 in the later 90 min,while the reaction orders for mass ratio of cellulose and ore were 0.660 and 0.724,respectively.An Arrhenius relationship was used to relate the temperature to the rate of leaching,from which apparent activation energies were calculated to be 46.487 kJ/mol and 62.290 kJ/mol at the two stages,respectively.Finally,the overall leaching rate equations for the manganese dissolution reaction with cellulose in sulphuric acid solution were developed.The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of SEM and XRD analyses.
