Nitrous oxide(N_(2)O),as an important gas affecting climate warming,is attracting attention from allwalks of life.This reviewaddresses N_(2)O emissions status in the adipic acid industry,a significant industrial green...Nitrous oxide(N_(2)O),as an important gas affecting climate warming,is attracting attention from allwalks of life.This reviewaddresses N_(2)O emissions status in the adipic acid industry,a significant industrial greenhouse gas source.It elucidates the N_(2)O emission mechanism and influencing factors in adipic acid production.It extensively evaluates N_(2)O emission accounting methods,including Intergovernmental Panel on Climate Change(IPCC)Guidelines,World Resources Institute(WRI)Protocol,and others.While the IPCC emission factor method offers simplicity and comparability,it may lack precision for facilities with advanced emission reduction measures.To address this,a combined modeling and monitoring approach is advocated.It scrutinizes modeling methods(statistical techniques,Greenhouse Gas and Air Pollution Interactions and Synergies,and Life-cycle Assessment)and highlights their reliance on specific data and perspectives.It emphasizes the growing importance of on-site monitoring with mid-IR technology.Additionally,it underscores the potential of aircraft-based and satellite remote sensing for comprehensive N_(2)O emissions data.The reviewalso highlights recent advancements in emission mitigation,particularly in adipic acid synthesis techniques,showing substantial potential for N_(2)O reduction.Innovative paradigms and strategies for N_(2)O mitigation in the adipic acid industry are presented,with a focus on achieving nitrogen oxides(NO_(x))-free production.These approaches hold promise for emission reduction,given the high removal efficiency in plant end-of-treatment processes.Various accounting methods,monitoring techniques,and mitigation strategies were integrated and analyzed to provides a comprehensive overview of N_(2)O emissions in the adipic acid industry,with the aim of guiding future research and policy initiatives.展开更多
The direct oxidation of cyclohexane to adipic acid(AA)without the use of HNO_(3)is important but still challenging.Herein,hierarchical manganese-containing TS-1 zeolite(HMTS)was prepared using an improved direct synth...The direct oxidation of cyclohexane to adipic acid(AA)without the use of HNO_(3)is important but still challenging.Herein,hierarchical manganese-containing TS-1 zeolite(HMTS)was prepared using an improved direct synthesis method,in which titanium and manganese coexist within the zeolite matrix,as characterized by X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,ultraviolet,extended X-ray absorption fine structure etc.The introduction of matrix Mn species(Mn^(3+),Mn^(4+))not only increased the surface oxygen vacancies,but also generated medium-strong acid sites,which endowed HMTS catalysts with the ability to efficiently activate oxygen and facilitate substrate coordination.On HMTS-3,one-pot oxidation of cyclohexane at 140℃and 2 MPa O_(2)gave 81.6%conversion and 71.5%AA selectivity,the highest value obtained at present.Control experiments with single-component samples confirmed that matrix Ti^(4+)catalyzed the conversion of cyclohexane to a mixture of cyclohexanone and cyclohexanol(KA oil),and matrix Mn favored the conversion of KA oil to AA.The synergy between matrix Ti and Mn inside the hierarchical structure were the key factor for the superior activity.Specifically,the matrix Ti^(4+)might activate oxygen to form Ti-O_(2)2-which facilitated the activation of the C-H bond of cyclohexane.The activation of O_(2)on matrix Mn^(3+)formed Mn^(4+)-O_(2)-favoring the breaking of the C-C bond of cyclohexanone.The hierarchical structure not only exposed more active sites and promoted mass transfer,but also provided a better microenvironment for the matrix Mn to synergize with the matrix Ti,which facilitated the overall reaction.This work demonstrated the practical application potential of HMTS and provided useful insights into the direct oxidation of cyclohexane to AA.展开更多
Constructing electrocatalytic overall reaction technology to couple the electrosynthesis of adipic acid with energy-saving hydrogen production is of significant for sustainable energy systems.However,the development o...Constructing electrocatalytic overall reaction technology to couple the electrosynthesis of adipic acid with energy-saving hydrogen production is of significant for sustainable energy systems.However,the development of highly-active bifunctional electrocatalysts remains a challenge.Herein,3D hierarchical nickel-copper alloying arrays with dendritic morphology are manufactured by a simple electrodeposition process,standing for the excellent bifunctional electrocatalyst towards the co-production of adipic acid and H_(2)from cyclohexanone and water.The membrane-free flow electrolyzer of Cu_(0.81)Ni_(0.19)/NF shows the superior electrooxidation performance of ketone-alcohol(KA)oil with high faradaic efficiencies of over 90%for adipic acid and H_(2),robust stability over 200 h as well as a high yield of 0.6 mmol h^(-1) for adipic acid at 100 mA cm^(-2).In-situ spectroscopy indicates the Cu_(0.81)Ni_(0.19)alloy contributes to forming more active NiOOH species to involve in the conversion of cyclohexanone to adipic acid,while the proposed reaction pathway undergoes the 2-hydroxycyclohexanone and 2,7-oxepanedione intermediates.Moreover,the theoretical calculations confirm that the optimal electronic interaction,boosted reaction kinetics as well as improved adsorption free energy of reaction intermediates,synergistically endows Cu_(0.81)Ni_(0.19)alloy with superior bifunctional performance.展开更多
The influence of adipic acid on the formation and corrosion resistance of anodic oxide film fabricated on 2024 aluminum alloy was investigated. The morphology was investigated by scanning electron microscopy （SEM） a...The influence of adipic acid on the formation and corrosion resistance of anodic oxide film fabricated on 2024 aluminum alloy was investigated. The morphology was investigated by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）, respectively. The corrosion resistance was evaluated by electrochemical impedance spectroscopy （EIS）. The results showed that the adipic acid was absorbed at the electrolyte/anodic layer interface during anodizing. The corrosion rate of anodic film decreased and the film thickness increased. The film was uniform and compact especially at the film/substrate interface. After sealing procedure, anodic film formed with the addition of adipic acid exhibited improved dielectric property and corrosion resistance in aggressive environment.展开更多
Using a laser detecting system, solubility data were measured for adipic acid dissolved in six pure solvents, namely, cyclohexanone, cyclohexanol, acetic acid, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethy...Using a laser detecting system, solubility data were measured for adipic acid dissolved in six pure solvents, namely, cyclohexanone, cyclohexanol, acetic acid, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethylsulfoxide at the temperature range from 293.15K to 353.15K. All these data were regressed by 2h, NRTL, Wilson, and the modified Wilson models. For the study of six, 2h, NRTL, and the modified Wilson models were found to provide an accurate mathematical representation of the experimental results, with overall average absolute relative deviations between measured and calculated values as 1.74%, 2.06%, and 3.06%, respectively. The results showed that the λh model is the most suitable for description of the solid-liquid equilibrium containing adipic acid.展开更多
Adipic acid is a dicarboxylic acid of great industrial importance,mainly used in the production of nylon-6,6 and polyurethane.The use of nitric acid as an oxidant in the industrial production of adipic acid poses sign...Adipic acid is a dicarboxylic acid of great industrial importance,mainly used in the production of nylon-6,6 and polyurethane.The use of nitric acid as an oxidant in the industrial production of adipic acid poses significant carbon footprint to the environment.Clean adipic acid synthesis methods using a heterogeneous catalyst with H2O2 as oxidant and water as solvent have potential advantages of low catalyst cost,easy synthesis and recovery,cleanness and environmental protection.In this work,hexagonal mesoporous silicate materials were synthesized by a sol–gel method and evaluated for cyclohexanol/cyclohexanone oxidation to adipic acid.The physical and chemical properties of Fe-HMS were characterized by XRD,HR-TEM,BET and UV–Vis.The experimental results showed that Fe-HMS materials show pore sizes ranging from 2–3 nm.W-and Mo-based polyoxometalates were also evaluated and compared to the Fe-based HMS catalysts.To improve the adipic acid yield,the influence of the transition metal as well as the effect of metal loading,reaction temperature and catalyst amount on the catalytic performances of Fe-HMS have been investigated in details.When Si/Fe atomic ratio=100,Fe-HMS catalyst shows the highest activity,with a cyclohexanone conversion of 92.3%and adipic acid selectivity of 29.4%.The reaction pathway of cyclohexanone oxidation was further proposed based on experimental data.展开更多
Using a simple and reliable apparatus, the solubilities of adipic acid in water, ethanol, chloroform, n-butanol and acetone are determined by the analytic method. The results are correlated with λh equation, Apelblat...Using a simple and reliable apparatus, the solubilities of adipic acid in water, ethanol, chloroform, n-butanol and acetone are determined by the analytic method. The results are correlated with λh equation, Apelblat equation, and UNIFAC equation. The solubilities calculated by these models are in good agreement with experi-mental data, so that the models can meet the requirements of engineering design.展开更多
The reaction mechanism of the liquid phase ammoniation of adipic acid to adiponitrile was studied experimentally in a semi-batch reactor. Macrokinetics of the main and side reactions were identified to minimize corros...The reaction mechanism of the liquid phase ammoniation of adipic acid to adiponitrile was studied experimentally in a semi-batch reactor. Macrokinetics of the main and side reactions were identified to minimize corrosion and coking to prolong the operation period, to increase the yield of adiponitrile and to improve the design of the reactor. Macrokinetic equations of ammoniation-neutralization of adipic acid and dehydration were of first-order to adipic concentration cB≥3.5% and of second order for cB≥3.5%. Catalyst H3PO4 reduced the activation energy of neutralization and dehydration reactions of adipic acid and was significantly important for the second step of dehydration to produce adiponitrile.展开更多
The adipic acid is an important intermediate in the production of nylon,polyurethane and polye ster resin s.The industrial approach for preparing adipic acid is through the liquid catalytic oxidation of KA oil with ni...The adipic acid is an important intermediate in the production of nylon,polyurethane and polye ster resin s.The industrial approach for preparing adipic acid is through the liquid catalytic oxidation of KA oil with nitric acid.In this work,a comprehensive model is developed for this reaction based on the kinetic study conducted in a continuous flow tubular reactor.The kinetic model fits well with the experimental results across the experimental conditions,and the average relative error between the calculated and experimental values is 5.7%.Results show that there was an induction period at the early stage of reaction.Moreover,it is found that at temperature range of 328-358 K,the formation rate of adipic acid strongly dependents on the temperature and nitric acid concentration.The developed model is used to predict the yield of adipic acid at 359-368 K.The work in this study could provide much knowledge for industrial tubular reactor design.展开更多
Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate ...Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate greenhouse gas control roadmaps.The forecasting method of this paper is consistent with the published national inventory in terms of caliber.Based on the N_2 O abatement technical parameters of adipic acid and the production trend,this paper combines the scenario analysis and provides a measurement of comprehensive N_2 O abatement effect of the entire industry in China.Four future scenarios are assumed.The baseline scenario(BAUS) is a frozen scenario.Three emission abatement scenarios(ANAS,SNAS,and ENAS) are assumed under different strength of abatement driving parameters.The results show that China's adipic acid production process can achieve increasingly significant N_2 O emission abatement effects.Compared to the baseline scenario,by 2030,the N_2 O emission abatements of the three emission abatement scenarios can reach 207-399 kt and the emission abatement ratios can reach 32.5%-62.6%.By 2050,the N_2 O emission abatements for the three emission abatement scenarios can reach 387-540 kt and the emission abatement ratios can reach 71.4%-99.6%.展开更多
The ring-opening copolymerization of adipic anhydride with propylene oxide was carried out with yttrium triflates as a catalyst. Poly（propylene adipate） could be synthesized by controlling the copolymerization condi...The ring-opening copolymerization of adipic anhydride with propylene oxide was carried out with yttrium triflates as a catalyst. Poly（propylene adipate） could be synthesized by controlling the copolymerization conditions. The copolymerization procedure was tracked by ^1H NMR analyses.展开更多
The goal of this work was to measure the heat transfer rates from thermofluid, Therminol 66, to two phase change materials, D-mannitol and adipic acid. It concerns the determination of heat transfer coefficients for t...The goal of this work was to measure the heat transfer rates from thermofluid, Therminol 66, to two phase change materials, D-mannitol and adipic acid. It concerns the determination of heat transfer coefficients for the design of a concentrated solar energy plant requiring PCM thermal energy storage and is part of a wider set of experiments, where several PCMs were tested. An experimental installation was used with a cylindrical vessel with three tubes disposed almost horizontally (5°inclination), containing the phase change material, around which the thermal fluid flowed almost perpendicular to the tubes. The experimental installation allowed to recreate heating and cooling cycles. In order to evaluate the influence of the flow on the rate at which the heating and cooling processes took place, tests were performed at different thermofluid mass flow rates, concluding that there is no great influence, since the thermal resistance inside the tubes is much higher than on the outside. D-mannitol and adipic acid, present different phase change temperatures, 164°C for D-mannitol and 152°C for adipic acid. The average heat transfer coefficient, during the phase change process, was of 340 W/(m<sup>2</sup>K) for D-mannitol and 1320 W/(m<sup>2</sup>K) for adipic acid.展开更多
The influences of kinds and level of catalyst, time of decomposition reaction on the distribution of dibasic acid and apparent yield of adipic acid were researched; the acidic washing waste water （BI waste water） pr...The influences of kinds and level of catalyst, time of decomposition reaction on the distribution of dibasic acid and apparent yield of adipic acid were researched; the acidic washing waste water （BI waste water） producing from the equipment of cyclohexane oxidation by air was as stuff, the component of products by decomposed and oxidated in different conditions were analysed. It indicated that in the presence of cobalt salt the apparent yield of adipic acid was upto 10%-12% for the total BI waste water after the concentrated BI waste water refluxed for two hours, and then oxidated by nitric acid.展开更多
Nitrous gas is one of the chemicals often produced in adipic acid production, which will have a certain impact on the environment. Therefore, people attach importance to the production, and people's requirements f...Nitrous gas is one of the chemicals often produced in adipic acid production, which will have a certain impact on the environment. Therefore, people attach importance to the production, and people's requirements for quality of life are getting higher and higher with the development of economy. Therefore, in the development of chemical industry, we should pay attention to optimizing the air environment, including nitrous gas in common harmful chemical gases, which will have an impact on the air. To improve the overall air quality, we should be scientific and reasonable. This paper mainly analyzes the production of Jill acid and discusses the recovery of nitrite gas, hoping to bring help and reference to relevant personnel.展开更多
Adipic acid(ADA)serves as a crucial monomer for the manufacturing of nylon and polyurethanes.However,current production methods are based on petrochemical feedstocks and pose significant environmental concerns.Consequ...Adipic acid(ADA)serves as a crucial monomer for the manufacturing of nylon and polyurethanes.However,current production methods are based on petrochemical feedstocks and pose significant environmental concerns.Consequently,the development of an innovative catalytic system for producing ADA from renewable biomass-derived feedstocks is of significant importance.Herein,we report a novel one-pot,two-step process for the highly efficient synthesis of ADA from the biomass derivative 2-furoic acid via hydrogenative carbonylation.In the first step,2-furoic acid is selectively reduced to 2-tetrahydrofuroic acid using a Rh catalyst with acetic acid(AcOH)and water(H_(2)O)as solvents.Subsequently,within the same catalytic system,the addition of I_(2) as a promoter enables the further conversion of 2-tetrahydrofuroic acid to ADA through a highly selective carbonylation reaction under CO and H_(2) atmospheres.This one-pot,two-step process achieved an ADA yield of 91.4% from 2-furoic acid.Mechanistic studies revealed that 5-iodopentanoic acid is the key intermediate in the carbonylation process.In summary,this research introduces an innovative and environmentally friendly approach for synthesizing ADA from biomass-derived 2-furoic acid,offering great potential for industrial application.展开更多
Carbon dots(CDs)have uniquely structural,physicochemical and photochemical properties,suggesting a promising platform for catalysis applications.The in-depth understanding of the structure-activity relationship in the...Carbon dots(CDs)have uniquely structural,physicochemical and photochemical properties,suggesting a promising platform for catalysis applications.The in-depth understanding of the structure-activity relationship in the CDs-based catalyst system needs to know the effect of the crystalline core on their catalytic performance.The efficient catalytic oxidation of cyclohexane is an urgent challenge in current chemical industry,in which,adipic acid(AA)plays an important role in industry for synthesis of nylon6 and nylon-66.Here,we fabricated the pristine CDs by electrochemical etching graphite rod method and derived CDs with high crystalline core(CD-600,CD-800,and CD-1100)through a thermal treatment method in tube furnace.Furthermore,these CDs performed an outstanding catalytic performance for one-step synthesis of AA from cyclohexane.With the help of machine learning(ML),the deep correlations between features(structures of CDs,catalytic conditions)and catalytic performances were investigated by XGBoost(XGB)model.Then under the optimization and prediction of XGB,it was found that high crystalline core preceded the other features and CD-1100 could get the best conversion of 30.696%and selectivity to AA of 92.52%at reaction conditions of 130℃,1.5 MPa,and 10 h.This work pioneered the application of ML in industrial issues and demonstrated a comprehensive understanding on CDs as catalyst to realize one-step synthesis of AA.展开更多
The ring-opening polymerization of adipic anhydride and the ring-opening copolymerization of adipic anhydride with ε-caprolactone catalyzed by single component rare earth trisphenolate have been reported. The structu...The ring-opening polymerization of adipic anhydride and the ring-opening copolymerization of adipic anhydride with ε-caprolactone catalyzed by single component rare earth trisphenolate have been reported. The structure of the copolymer poly（CL-b-AA） has been characterized by SEC, ^1H NMR and DSC.展开更多
This paper describes a formation of hybrid coatings on a Ti-2Ta-3Zr-36Nb surface.This is accomplished by plasma electrolytic oxidation and a dip-coating technique with poly(adipic anhydride)((C6H8O3)n)that is loaded w...This paper describes a formation of hybrid coatings on a Ti-2Ta-3Zr-36Nb surface.This is accomplished by plasma electrolytic oxidation and a dip-coating technique with poly(adipic anhydride)((C6H8O3)n)that is loaded with drugs:amoxicillin(C16H19N3O5S),cefazolin(C14H14N8O4S3)or vancomycin(C66H75Cl2N9O24·xHCl).The characteristic microstructure of the polymer was evaluated using scanning electron microscopy and confocal microscopy.Depending on the surface treatment,the surface roughness varied(between 1.53μm and 2.06μm),and the wettability was change with the over of time.X-ray photoelectron spectroscopy analysis showed that the oxide layer did not affect the polymer layer or loaded drugs.However,the drugs lose their stability in a phosphate-buffered saline solution after 6.5 h of exposure,and its decrease was greater than 7%(HPLC analysis).The stability,drug release and concentration of the drug loaded into the material were precisely analyzed by high-performance liquid chromatography.The results correlated with the degradation of the polymer in which the addition of drugs caused the percent of degraded polymer to be between 35.5%and 49.4%after 1 h of material immersion,depending on the mass of the loaded drug and various biological responses that were obtained.However,all of the coatings were cytocompatible with MG-63 osteoblast-like cells.The drug concentrations released from the coatings were sufficient to inhibit adhesion of reference and clinical bacterial strains(S.aureus).The coatings with amoxicillin showed the best results in the bacterial inhibition zone,whereas coatings with cefazolin inhibited adhesion of the above bacteria on the surface.展开更多
The catalysis of chloridized metalloporphyrins in the oxidation of cyclohexane to adipic acid was systemati-cally investigated.The turnover numbers(TON)data of 19 catalysts were obtained experimentally under optimal r...The catalysis of chloridized metalloporphyrins in the oxidation of cyclohexane to adipic acid was systemati-cally investigated.The turnover numbers(TON)data of 19 catalysts were obtained experimentally under optimal reac-tion conditions,and 2.4x106 TON for T(o-Cl)PP-MnIIICl catalyst at 2.0x10–6 mol/L of dosage was reached under the conditions of dioxygen pressure of 2.5 MPa at 150°C for 4 h.This was the best result reported for this reaction up to now.The QSAR models for each concerned metallopor-phyrin were established,where the catalytic activity was significantly correlated with the ELUMO(the energy level of the lowest unoccupied molecule orbit)and LM-N(the bond length between metal-nitrogen atoms).Using the QSAR models,four new metalloporphyrins with substituted nitro group were designed,and their catalytic activities were predicted.The experimental TON data of newly designed porphyrins were in good agreement with the predicted ones,and the square of their correlation coefficient was more than 0.958.The above results demonstrated that the proposed structure-activity relationship model could be applied to design some new metalloporphyrin catalysts,and to predict their catalytic activity in cyclohexane oxidation.展开更多
基金supported by the National Key R&D Program of China(No.2023YFC3707201)the National Natural Science Foundation of China(No.52320105003)+1 种基金the Informatization Plan of Chinese Academy of Sciences(No.CAS-WX2023PY-0103)the Fundamental Research Funds for the Central Universities(No.E3ET1803).
文摘Nitrous oxide(N_(2)O),as an important gas affecting climate warming,is attracting attention from allwalks of life.This reviewaddresses N_(2)O emissions status in the adipic acid industry,a significant industrial greenhouse gas source.It elucidates the N_(2)O emission mechanism and influencing factors in adipic acid production.It extensively evaluates N_(2)O emission accounting methods,including Intergovernmental Panel on Climate Change(IPCC)Guidelines,World Resources Institute(WRI)Protocol,and others.While the IPCC emission factor method offers simplicity and comparability,it may lack precision for facilities with advanced emission reduction measures.To address this,a combined modeling and monitoring approach is advocated.It scrutinizes modeling methods(statistical techniques,Greenhouse Gas and Air Pollution Interactions and Synergies,and Life-cycle Assessment)and highlights their reliance on specific data and perspectives.It emphasizes the growing importance of on-site monitoring with mid-IR technology.Additionally,it underscores the potential of aircraft-based and satellite remote sensing for comprehensive N_(2)O emissions data.The reviewalso highlights recent advancements in emission mitigation,particularly in adipic acid synthesis techniques,showing substantial potential for N_(2)O reduction.Innovative paradigms and strategies for N_(2)O mitigation in the adipic acid industry are presented,with a focus on achieving nitrogen oxides(NO_(x))-free production.These approaches hold promise for emission reduction,given the high removal efficiency in plant end-of-treatment processes.Various accounting methods,monitoring techniques,and mitigation strategies were integrated and analyzed to provides a comprehensive overview of N_(2)O emissions in the adipic acid industry,with the aim of guiding future research and policy initiatives.
文摘The direct oxidation of cyclohexane to adipic acid(AA)without the use of HNO_(3)is important but still challenging.Herein,hierarchical manganese-containing TS-1 zeolite(HMTS)was prepared using an improved direct synthesis method,in which titanium and manganese coexist within the zeolite matrix,as characterized by X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,ultraviolet,extended X-ray absorption fine structure etc.The introduction of matrix Mn species(Mn^(3+),Mn^(4+))not only increased the surface oxygen vacancies,but also generated medium-strong acid sites,which endowed HMTS catalysts with the ability to efficiently activate oxygen and facilitate substrate coordination.On HMTS-3,one-pot oxidation of cyclohexane at 140℃and 2 MPa O_(2)gave 81.6%conversion and 71.5%AA selectivity,the highest value obtained at present.Control experiments with single-component samples confirmed that matrix Ti^(4+)catalyzed the conversion of cyclohexane to a mixture of cyclohexanone and cyclohexanol(KA oil),and matrix Mn favored the conversion of KA oil to AA.The synergy between matrix Ti and Mn inside the hierarchical structure were the key factor for the superior activity.Specifically,the matrix Ti^(4+)might activate oxygen to form Ti-O_(2)2-which facilitated the activation of the C-H bond of cyclohexane.The activation of O_(2)on matrix Mn^(3+)formed Mn^(4+)-O_(2)-favoring the breaking of the C-C bond of cyclohexanone.The hierarchical structure not only exposed more active sites and promoted mass transfer,but also provided a better microenvironment for the matrix Mn to synergize with the matrix Ti,which facilitated the overall reaction.This work demonstrated the practical application potential of HMTS and provided useful insights into the direct oxidation of cyclohexane to AA.
基金financially supported by the National Natural Science Foundation of China(22205205,22472151)the Zhejiang Provincial Natural Science Foundation of China(LQ22B030008)the Science Foundation of Zhejiang Sci-Tech University(ZSTU)under Grant No.21062337-Y.
文摘Constructing electrocatalytic overall reaction technology to couple the electrosynthesis of adipic acid with energy-saving hydrogen production is of significant for sustainable energy systems.However,the development of highly-active bifunctional electrocatalysts remains a challenge.Herein,3D hierarchical nickel-copper alloying arrays with dendritic morphology are manufactured by a simple electrodeposition process,standing for the excellent bifunctional electrocatalyst towards the co-production of adipic acid and H_(2)from cyclohexanone and water.The membrane-free flow electrolyzer of Cu_(0.81)Ni_(0.19)/NF shows the superior electrooxidation performance of ketone-alcohol(KA)oil with high faradaic efficiencies of over 90%for adipic acid and H_(2),robust stability over 200 h as well as a high yield of 0.6 mmol h^(-1) for adipic acid at 100 mA cm^(-2).In-situ spectroscopy indicates the Cu_(0.81)Ni_(0.19)alloy contributes to forming more active NiOOH species to involve in the conversion of cyclohexanone to adipic acid,while the proposed reaction pathway undergoes the 2-hydroxycyclohexanone and 2,7-oxepanedione intermediates.Moreover,the theoretical calculations confirm that the optimal electronic interaction,boosted reaction kinetics as well as improved adsorption free energy of reaction intermediates,synergistically endows Cu_(0.81)Ni_(0.19)alloy with superior bifunctional performance.
基金Project(51271012)supported by the National Natural Science Foundation of China
文摘The influence of adipic acid on the formation and corrosion resistance of anodic oxide film fabricated on 2024 aluminum alloy was investigated. The morphology was investigated by scanning electron microscopy （SEM） and transmission electron microscopy （TEM）, respectively. The corrosion resistance was evaluated by electrochemical impedance spectroscopy （EIS）. The results showed that the adipic acid was absorbed at the electrolyte/anodic layer interface during anodizing. The corrosion rate of anodic film decreased and the film thickness increased. The film was uniform and compact especially at the film/substrate interface. After sealing procedure, anodic film formed with the addition of adipic acid exhibited improved dielectric property and corrosion resistance in aggressive environment.
文摘Using a laser detecting system, solubility data were measured for adipic acid dissolved in six pure solvents, namely, cyclohexanone, cyclohexanol, acetic acid, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethylsulfoxide at the temperature range from 293.15K to 353.15K. All these data were regressed by 2h, NRTL, Wilson, and the modified Wilson models. For the study of six, 2h, NRTL, and the modified Wilson models were found to provide an accurate mathematical representation of the experimental results, with overall average absolute relative deviations between measured and calculated values as 1.74%, 2.06%, and 3.06%, respectively. The results showed that the λh model is the most suitable for description of the solid-liquid equilibrium containing adipic acid.
基金supported by the National Natural Science Foundation(21706290)Natural Science Foundation of Shandong Province(ZR2017MB004,ZR2017BB007)+5 种基金Postdoctoral Research Funding of Shandong Province(201703016)Fundamental Research Funding of Qingdao(17-1-1-67-jch,17-1-1-80-jch)Qingdao Postdoctoral Research Funding(BY20170210)“the Fundamental Research Funds for the Central Universities”(18CX02145A,17CX02017A)new faculty start-up funding from China University of Petroleum(YJ201601058)China Postdoctoral Science Foundation(2017M612374)。
文摘Adipic acid is a dicarboxylic acid of great industrial importance,mainly used in the production of nylon-6,6 and polyurethane.The use of nitric acid as an oxidant in the industrial production of adipic acid poses significant carbon footprint to the environment.Clean adipic acid synthesis methods using a heterogeneous catalyst with H2O2 as oxidant and water as solvent have potential advantages of low catalyst cost,easy synthesis and recovery,cleanness and environmental protection.In this work,hexagonal mesoporous silicate materials were synthesized by a sol–gel method and evaluated for cyclohexanol/cyclohexanone oxidation to adipic acid.The physical and chemical properties of Fe-HMS were characterized by XRD,HR-TEM,BET and UV–Vis.The experimental results showed that Fe-HMS materials show pore sizes ranging from 2–3 nm.W-and Mo-based polyoxometalates were also evaluated and compared to the Fe-based HMS catalysts.To improve the adipic acid yield,the influence of the transition metal as well as the effect of metal loading,reaction temperature and catalyst amount on the catalytic performances of Fe-HMS have been investigated in details.When Si/Fe atomic ratio=100,Fe-HMS catalyst shows the highest activity,with a cyclohexanone conversion of 92.3%and adipic acid selectivity of 29.4%.The reaction pathway of cyclohexanone oxidation was further proposed based on experimental data.
基金Supported by the Natural Science Foundation of Henan Province (0511021700)
文摘Using a simple and reliable apparatus, the solubilities of adipic acid in water, ethanol, chloroform, n-butanol and acetone are determined by the analytic method. The results are correlated with λh equation, Apelblat equation, and UNIFAC equation. The solubilities calculated by these models are in good agreement with experi-mental data, so that the models can meet the requirements of engineering design.
文摘The reaction mechanism of the liquid phase ammoniation of adipic acid to adiponitrile was studied experimentally in a semi-batch reactor. Macrokinetics of the main and side reactions were identified to minimize corrosion and coking to prolong the operation period, to increase the yield of adiponitrile and to improve the design of the reactor. Macrokinetic equations of ammoniation-neutralization of adipic acid and dehydration were of first-order to adipic concentration cB≥3.5% and of second order for cB≥3.5%. Catalyst H3PO4 reduced the activation energy of neutralization and dehydration reactions of adipic acid and was significantly important for the second step of dehydration to produce adiponitrile.
基金the Ningbo Science and Technology Plan Project (2018B10013)the Program of Shanghai Subject Chief Scientist (18XD1402000)。
文摘The adipic acid is an important intermediate in the production of nylon,polyurethane and polye ster resin s.The industrial approach for preparing adipic acid is through the liquid catalytic oxidation of KA oil with nitric acid.In this work,a comprehensive model is developed for this reaction based on the kinetic study conducted in a continuous flow tubular reactor.The kinetic model fits well with the experimental results across the experimental conditions,and the average relative error between the calculated and experimental values is 5.7%.Results show that there was an induction period at the early stage of reaction.Moreover,it is found that at temperature range of 328-358 K,the formation rate of adipic acid strongly dependents on the temperature and nitric acid concentration.The developed model is used to predict the yield of adipic acid at 359-368 K.The work in this study could provide much knowledge for industrial tubular reactor design.
基金financial support by the Ministry of Science and Technology of China (Grant No.2018YFC1509006)the National Natural Science Foundation of China (Grant No.71874096)+1 种基金the Macao SAR Government Higher Education Fundthe Macao University of Science and Technology (Grant No.FRG-19-008-MSB)。
文摘Adipic acid is an important petrochemical product,and its production process emits a high concentration of greenhouse gas N_2 O.This paper aims to provide quantitative references for relevant authorities to formulate greenhouse gas control roadmaps.The forecasting method of this paper is consistent with the published national inventory in terms of caliber.Based on the N_2 O abatement technical parameters of adipic acid and the production trend,this paper combines the scenario analysis and provides a measurement of comprehensive N_2 O abatement effect of the entire industry in China.Four future scenarios are assumed.The baseline scenario(BAUS) is a frozen scenario.Three emission abatement scenarios(ANAS,SNAS,and ENAS) are assumed under different strength of abatement driving parameters.The results show that China's adipic acid production process can achieve increasingly significant N_2 O emission abatement effects.Compared to the baseline scenario,by 2030,the N_2 O emission abatements of the three emission abatement scenarios can reach 207-399 kt and the emission abatement ratios can reach 32.5%-62.6%.By 2050,the N_2 O emission abatements for the three emission abatement scenarios can reach 387-540 kt and the emission abatement ratios can reach 71.4%-99.6%.
基金Supported by the National Natural Science Foundation of China(Nos.20704036, Key Program 20434020)the State Basic Research Projects of China(No.2005CB623802)
文摘The ring-opening copolymerization of adipic anhydride with propylene oxide was carried out with yttrium triflates as a catalyst. Poly（propylene adipate） could be synthesized by controlling the copolymerization conditions. The copolymerization procedure was tracked by ^1H NMR analyses.
文摘The goal of this work was to measure the heat transfer rates from thermofluid, Therminol 66, to two phase change materials, D-mannitol and adipic acid. It concerns the determination of heat transfer coefficients for the design of a concentrated solar energy plant requiring PCM thermal energy storage and is part of a wider set of experiments, where several PCMs were tested. An experimental installation was used with a cylindrical vessel with three tubes disposed almost horizontally (5°inclination), containing the phase change material, around which the thermal fluid flowed almost perpendicular to the tubes. The experimental installation allowed to recreate heating and cooling cycles. In order to evaluate the influence of the flow on the rate at which the heating and cooling processes took place, tests were performed at different thermofluid mass flow rates, concluding that there is no great influence, since the thermal resistance inside the tubes is much higher than on the outside. D-mannitol and adipic acid, present different phase change temperatures, 164°C for D-mannitol and 152°C for adipic acid. The average heat transfer coefficient, during the phase change process, was of 340 W/(m<sup>2</sup>K) for D-mannitol and 1320 W/(m<sup>2</sup>K) for adipic acid.
文摘The influences of kinds and level of catalyst, time of decomposition reaction on the distribution of dibasic acid and apparent yield of adipic acid were researched; the acidic washing waste water （BI waste water） producing from the equipment of cyclohexane oxidation by air was as stuff, the component of products by decomposed and oxidated in different conditions were analysed. It indicated that in the presence of cobalt salt the apparent yield of adipic acid was upto 10%-12% for the total BI waste water after the concentrated BI waste water refluxed for two hours, and then oxidated by nitric acid.
文摘Nitrous gas is one of the chemicals often produced in adipic acid production, which will have a certain impact on the environment. Therefore, people attach importance to the production, and people's requirements for quality of life are getting higher and higher with the development of economy. Therefore, in the development of chemical industry, we should pay attention to optimizing the air environment, including nitrous gas in common harmful chemical gases, which will have an impact on the air. To improve the overall air quality, we should be scientific and reasonable. This paper mainly analyzes the production of Jill acid and discusses the recovery of nitrite gas, hoping to bring help and reference to relevant personnel.
基金funded by the National Natural Science Foundation of China(Grant no.22169011).
文摘Adipic acid(ADA)serves as a crucial monomer for the manufacturing of nylon and polyurethanes.However,current production methods are based on petrochemical feedstocks and pose significant environmental concerns.Consequently,the development of an innovative catalytic system for producing ADA from renewable biomass-derived feedstocks is of significant importance.Herein,we report a novel one-pot,two-step process for the highly efficient synthesis of ADA from the biomass derivative 2-furoic acid via hydrogenative carbonylation.In the first step,2-furoic acid is selectively reduced to 2-tetrahydrofuroic acid using a Rh catalyst with acetic acid(AcOH)and water(H_(2)O)as solvents.Subsequently,within the same catalytic system,the addition of I_(2) as a promoter enables the further conversion of 2-tetrahydrofuroic acid to ADA through a highly selective carbonylation reaction under CO and H_(2) atmospheres.This one-pot,two-step process achieved an ADA yield of 91.4% from 2-furoic acid.Mechanistic studies revealed that 5-iodopentanoic acid is the key intermediate in the carbonylation process.In summary,this research introduces an innovative and environmentally friendly approach for synthesizing ADA from biomass-derived 2-furoic acid,offering great potential for industrial application.
基金the National Key R&D Program of China(Nos.2020YFA0406103,2020YFA0406104,and 2020YFA0406101)National MCF Energy R&D Program of China(No.2018YFE0306105)+4 种基金Innovative Research Group Project of the National Natural Science Foundation of China(No.51821002)the National Natural Science Foundation of China(Nos.51725204,21771132,51972216,and 52041202)the Natural Science Foundation of Jiangsu Province(No.BK20190041)KeyArea Research and Development Program of GuangDong Province(No.2019B010933001)Collaborative Innovation Center of Suzhou Nano Science&Technology,the 111 Project,and Suzhou Key Laboratory of Functional Nano&Soft Materials.
文摘Carbon dots(CDs)have uniquely structural,physicochemical and photochemical properties,suggesting a promising platform for catalysis applications.The in-depth understanding of the structure-activity relationship in the CDs-based catalyst system needs to know the effect of the crystalline core on their catalytic performance.The efficient catalytic oxidation of cyclohexane is an urgent challenge in current chemical industry,in which,adipic acid(AA)plays an important role in industry for synthesis of nylon6 and nylon-66.Here,we fabricated the pristine CDs by electrochemical etching graphite rod method and derived CDs with high crystalline core(CD-600,CD-800,and CD-1100)through a thermal treatment method in tube furnace.Furthermore,these CDs performed an outstanding catalytic performance for one-step synthesis of AA from cyclohexane.With the help of machine learning(ML),the deep correlations between features(structures of CDs,catalytic conditions)and catalytic performances were investigated by XGBoost(XGB)model.Then under the optimization and prediction of XGB,it was found that high crystalline core preceded the other features and CD-1100 could get the best conversion of 30.696%and selectivity to AA of 92.52%at reaction conditions of 130℃,1.5 MPa,and 10 h.This work pioneered the application of ML in industrial issues and demonstrated a comprehensive understanding on CDs as catalyst to realize one-step synthesis of AA.
基金Project supported by the National Natural Science Foundation of China （No. 020434020）, Special Fund for Major State Basic Research Projects （No 2005CB623800） and the Committee of Science and Technology of Zhejiang Province.
文摘The ring-opening polymerization of adipic anhydride and the ring-opening copolymerization of adipic anhydride with ε-caprolactone catalyzed by single component rare earth trisphenolate have been reported. The structure of the copolymer poly（CL-b-AA） has been characterized by SEC, ^1H NMR and DSC.
基金supported by the National Science Centre,Poland(UMO-2016/21/D/ST5/01652)supported by Rector's Grant in the field of research and development(Silesian University of Technology,Poland,04/010/RGJ19/0095).
文摘This paper describes a formation of hybrid coatings on a Ti-2Ta-3Zr-36Nb surface.This is accomplished by plasma electrolytic oxidation and a dip-coating technique with poly(adipic anhydride)((C6H8O3)n)that is loaded with drugs:amoxicillin(C16H19N3O5S),cefazolin(C14H14N8O4S3)or vancomycin(C66H75Cl2N9O24·xHCl).The characteristic microstructure of the polymer was evaluated using scanning electron microscopy and confocal microscopy.Depending on the surface treatment,the surface roughness varied(between 1.53μm and 2.06μm),and the wettability was change with the over of time.X-ray photoelectron spectroscopy analysis showed that the oxide layer did not affect the polymer layer or loaded drugs.However,the drugs lose their stability in a phosphate-buffered saline solution after 6.5 h of exposure,and its decrease was greater than 7%(HPLC analysis).The stability,drug release and concentration of the drug loaded into the material were precisely analyzed by high-performance liquid chromatography.The results correlated with the degradation of the polymer in which the addition of drugs caused the percent of degraded polymer to be between 35.5%and 49.4%after 1 h of material immersion,depending on the mass of the loaded drug and various biological responses that were obtained.However,all of the coatings were cytocompatible with MG-63 osteoblast-like cells.The drug concentrations released from the coatings were sufficient to inhibit adhesion of reference and clinical bacterial strains(S.aureus).The coatings with amoxicillin showed the best results in the bacterial inhibition zone,whereas coatings with cefazolin inhibited adhesion of the above bacteria on the surface.
基金supported by the Key Project of Natural Science Foundation of Beijing(Grant No.2061001).
文摘The catalysis of chloridized metalloporphyrins in the oxidation of cyclohexane to adipic acid was systemati-cally investigated.The turnover numbers(TON)data of 19 catalysts were obtained experimentally under optimal reac-tion conditions,and 2.4x106 TON for T(o-Cl)PP-MnIIICl catalyst at 2.0x10–6 mol/L of dosage was reached under the conditions of dioxygen pressure of 2.5 MPa at 150°C for 4 h.This was the best result reported for this reaction up to now.The QSAR models for each concerned metallopor-phyrin were established,where the catalytic activity was significantly correlated with the ELUMO(the energy level of the lowest unoccupied molecule orbit)and LM-N(the bond length between metal-nitrogen atoms).Using the QSAR models,four new metalloporphyrins with substituted nitro group were designed,and their catalytic activities were predicted.The experimental TON data of newly designed porphyrins were in good agreement with the predicted ones,and the square of their correlation coefficient was more than 0.958.The above results demonstrated that the proposed structure-activity relationship model could be applied to design some new metalloporphyrin catalysts,and to predict their catalytic activity in cyclohexane oxidation.
