Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.C...Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.Compared with the traditional coal-fired power plant flue gas emission reduction technology,carbon fixation and emission reduction by microalgae is considered as a promising technology due to the advantages of simple process equipment,convenient operation and environmental protection.When the flue gas is treated by microalgae carbon fixation and emission reduction technology,microalgae cells can fix CO_(2) in the flue gas through photosynthesis,and simultaneously absorb NO_(x) and SO_(x) as nitrogen and sulfur sources required for growth.Meanwhile,they can also absorb mercury,selenium,arsenic,cadmium,lead and other heavy metal ions in the flue gas to obtain microalgae biomass.The obtained microalgae biomass can be further transformed into high valueadded products,which has broad development prospects.This paper reviews the mechanisms and pathways of CO_(2) sequestration,the mechanism and impacts of microalgal emission reduction of flue gas pollutants,and the applications of carbon sequestration in industrial flue gas by microalgae.Finally,this paper provides some guidelines and prospects for the research and application of green emission reduction technology for industrial flue gas.展开更多
Silicon nanowires(SiNWs)have been used in a wide variety of applications over the past few decades due to their excellent material properties.The only drawback is the high production cost of SiNWs.The preparation of S...Silicon nanowires(SiNWs)have been used in a wide variety of applications over the past few decades due to their excellent material properties.The only drawback is the high production cost of SiNWs.The preparation of SiNWs from photovoltaic waste silicon(WSi)powders,which are high-volume industrial wastes,not only avoids the secondary energy consumption and environmental pollution caused by complicated recycling methods,but also realizes its high-value utilization.Herein,we present a method to rapidly convert photovoltaic WSi powders into SiNWs products.The flash heating and quenching provided by carbothermal shock induce the production of free silicon atoms from the WSi powders,which are rapidly reorganized and assembled into SiNWs during the vapor-phase process.This method allows for the one-step composite of SiNWs and carbon cloth(CC)and the formation of SiC at the interface of the silicon(Si)and carbon(C)contact to create a stable chemical connection.The obtained SiNWs-CC(SiNWs@CC)composites can be directly used as lithium anodes,exhibiting high initial coulombic efficiency(86.4%)and stable cycling specific capacity(2437.4 mA h g^(-1)at 0.5 A g^(-1)after 165 cycles).In addition,various SiNWs@C composite electrodes are easily prepared using this method.展开更多
Acrylic acid(AA)is an important and widely used industrial chemical,but its high toxicity renders its use incompatible with the concept of green development.By leveraging its terminal carboxyl group and unsaturated bo...Acrylic acid(AA)is an important and widely used industrial chemical,but its high toxicity renders its use incompatible with the concept of green development.By leveraging its terminal carboxyl group and unsaturated bond,we designed and explored a new strategy to increase the greenness of AA via its eutectic melting using a quaternary ammonium salt(choline chloride)to form a deep eutectic solvent(DES),followed by polymerisation of the DES to form a polymer(poly(DES)).The greenness of AA,DES,and poly(DES)was evaluated via an in vitro test using MGC80-3 cells and an in vivo test using Kunming mice.The toxicity improved from Grade 2(moderately toxic)for AA to Grade 1(slightly toxic)for DESs and Grade 0(non-toxic)for poly(DES)in the in vitro test.Moreover,the poly(DES)s showed a lower toxicity in mice than the DESs in the in vivo test.Thus,greenness enhancement was successfully achieved,with the greenness following the order AA<DES<poly(DES).Furthermore,the mechanisms underlying the change in toxicity were explored through microscopy and flow cytometry,which revealed that the DES can permeate the MGC80-3 cell membrane during the G_(0)/G_(1) phase to adversely affect DNA synthesis in the S phase,but the poly(DES)cannot.Finally,the green poly(DES),which showed good adsorption properties and flexible functionality,was successfully applied as a carrier or excipient of drugs.Through the novel strategy reported herein,greenness enhancement and the broadening of the application scope of a toxic organic acid were achieved,making such acids applicable for green development.展开更多
The efficient and environmentally friendly recycling technology of waste residue that including abundant heavy metal produced during the recovery of lithium batteries has become a research hotspot.Herein,a novelty pro...The efficient and environmentally friendly recycling technology of waste residue that including abundant heavy metal produced during the recovery of lithium batteries has become a research hotspot.Herein,a novelty process of acid leaching-selective electrodeposition-deep impurity removal-regeneration was proposed to recovery of the CuS slag,which has been efficient transferred to high purity cathode copper and commercially available ternary precursors.Copper cathode with a purity of 99.67%was prepared under electrochemical reaction conditions at-0.55 V for 2 h.A novel impurity remover-Mn powder,which was used to remove the residual impurities and as a feedstock for the ternary precursor.Finally,NCM523 was regenerated by co-precipitation.The process is superior to the traditional process in economy,energy consumption,CO_(2)emissions,product purity and process duration.This study provides a new approach for solid waste recovery and precious metal enrichment.展开更多
A double-effect reactive distillation(DERD)process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy cons...A double-effect reactive distillation(DERD)process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy consumption in the tubular plug-flow reactor.A single-column reactive distillation(RD)process was conducted under optimized operating conditions based on sensitivity analysis as a reference.The results demonstrated that the proposed DERD process is able to achieve more than 95%selectivity of the desired product.After that,a design approach of the DERD process with an objective of the minimum operating cost was proposed to achieve further energy savings in the RD process.The proposed DERD configuration can provide a large energy-savings by totally utilization of the overhead vapor steam in the high-pressure RD column.A comparison of the single-column RD process revealed that the proposed DERD process can reduce the operating cost and the total annual cost of 25.3%and 30.7%,respectively,even though the total capital cost of DERD process is larger than that of the RD process.展开更多
Vanadium is a strategic metal in many countries,and it is mainly extracted from vanadium slag produced in titanomagnetite metallurgy.The traditional sodium roasting process for vanadium extraction poses environmental ...Vanadium is a strategic metal in many countries,and it is mainly extracted from vanadium slag produced in titanomagnetite metallurgy.The traditional sodium roasting process for vanadium extraction poses environmental threats,and a green calcification pro-cess has been proposed.However,the vanadium extraction rate in the calcification process is much lower than in the sodium roasting pro-cess,which is related to vanadium solid solubility in Fe_(2)TiO_(5).Previous studies about vanadium behavior in Fe_(2)TiO_(5) were conducted in air,with a vanadium oxidation state of V5+.Vanadium with lower oxidation states has been detected in the tailings in the calcification process.The present paper studied the effects of vanadium oxidation states on the solid solubility in Fe_(2)TiO_(5) through solid-state reaction,X-ray diffraction characterization,transmission electron microscopy characterization,X-ray photoelectron spectroscopy analysis,and solid solu-tion modeling.The relative interaction values between vanadium oxides and Fe_(2)TiO_(5) are obtained as|L_(V_(2)O_(3))|>|L_(V_(2)O_(4))|>|L_(V_(2)O_(5)),indicating that vanadium with lower valence is preferable to be solid dissolved in Fe_(2)TiO_(5).The results imply that insufficiently oxidized vanadium increases the vanadium content in the Fe_(2)TiO_(5) phase during vanadium slag’s calcification roasting.Besides,experimental conditions op-timization shows that higher experimental temperature,vanadium introduction as V2O3,and a high-purity argon atmosphere would lead to higher vanadium solubility in Fe_(2)TiO_(5),and high temperature is beneficial for the release of vanadium from vanadium-containing Fe_(2)TiO_(5) when dissociated in air.展开更多
In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by io...In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by ion morphology pretreatme nt and solvent extraction.An acidic V(Ⅴ)/W(Ⅵ)solution was obtained using the me mbrane electrolysis method without adding any other chemical reagents.In addition,Na was recovered in the form of NaOH by product,avoiding the generation of Na containing wastewater.The electrolysis parameters were investigated,the lowest power consumption of 3063 kW·h·t^(-1)NaOH was obtained at a current density of 125 A·m^(-2)and an initial NaOH concentration of 2 mol·L^(-1).After electrolysis,oxalic acid was added to the acidic V/W containing solution,converting V(Ⅴ)negative ion to V(Ⅳ)positive ion.Since W(Ⅵ)ion state remained in negative form,the generation of heteropolyacid ions(W_(x)V_(y)O_(z)^(n-))was prevented.It was found that under the condition of oxalic acid addition/theoretical consumption 1.2 and reaction temperature 75℃,100%V(Ⅴ)was co nverted to V(Ⅳ4).Using 10%N263+10%noctanol+80%sulfonated kerosene as extractant,the highest W(Ⅵ)/V(Ⅳ)separation coefficient of 7559.76was obtained at pH=1.8,O:A ratio=1:1 and extraction time 15 min.With 2 mol·L^(-1)NaOH as stripping reagent,the W stripping efficiency reached 98.50%at O:A ratio=2:1 after 4-stages of stripping.The enrichment of V remained in the solution was realized using P204 as extractant and 20%(mass)H_(2)SO_(4)as stripping reagent.The parameters of extraction/stripping process were investigated,using 10%P204+10%TBP+80%sulfonated kerosene as extractant,the V extraction efficiency reached 97.50%at O:A ratio=1:2after 4 stages of extraction.Using 20%H_(2)SO_(4)as the stripping reagent,the V stripping efficiency was 98.30%at an O:A ratio of 4:1 after five stage s of stripping.After the entire process,a high-purity VOSO_(4)and Na_(2)WO_(4)product solutions were obtained with V/W recovery efficiency 95.84%/98.50%,separately.This study examined a more effective and cleaner method for separating V/W/Na in Na_(2)WO_(4)/NaVO_(3)solution,which may serve as a reference for the separation and recovery of V/W/Na in waste SCR catalysts.展开更多
A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling flows.In order to control vortex breakdown withi...A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling flows.In order to control vortex breakdown within the chamber,this study first establishes a computational fluid dynamics simulation coupled with the level set method.Verified by experimental results in literature,this method accurately simulates the position and shape of vortex breakdown,and also predicts the critical Reynolds numbers for the appearance and detachment of vortex breakdown bubbles from the center.Additionally,it precisely captures the gas-liquid interface and depicts the vortex breakdown phenomenon in the air above the liquid for the first time.Finally,it predicts the impact of physical property of gas-liquid systems on vortex breakdown in response to significant changes in viscosity of microbial process systems.展开更多
Ionic liquids (ILs) and deep eutectic solvents (DESs) as green solvents have attracted dramatic attention recently due to their highly tunable properties. However, traditional experimental screening methods are ineffi...Ionic liquids (ILs) and deep eutectic solvents (DESs) as green solvents have attracted dramatic attention recently due to their highly tunable properties. However, traditional experimental screening methods are inefficient and resource-intensive. The article provides a comprehensive overview of various ML algorithms, including artificial neural network (ANN), support vector machine (SVM), random forest (RF), and gradient boosting trees (GBT), etc., which have demonstrated exceptional performance in handling complex and high-dimensional data. Furthermore, the integration of ML with quantum chemical calculations and conductor-like screening model-real solvent (COSMO-RS) has significantly enhanced predictive accuracy, enabling the rapid screening and design of novel solvents. Besides, recent ML applications in the prediction and design of ILs and DESs focused on solubility, melting point, electrical conductivity, and other physicochemical properties become more and more. This paper emphasizes the potential of ML in solvent design, overviewing an efficient approach to accelerate the development of sustainable and high-performance materials, providing guidance for their widespread application in a variety of industrial processes.展开更多
MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due...MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due to its exceptional electrical conductivity,structural flexibility,and mechanical properties.This comprehensive review describes the sandwich-like structure of the synthesized MBene,derived from its multilayered parent material and its distinct chemical framework to date.The fields of focus encompass the investigation of novel MBenes,the study of phase-changing mechanisms,and the examination of hex-MBenes,ortho-MBenes,tetra-MBenes,tri-MBenes,and MXenes with identical transition metal components.A critical analysis is also provided on the electrochemical mechanism and performance of MBene in energy storage(Li/Na/Mg/Ca/Li–S batteries and supercapacitors),as well as conversion and harvesting(CO_(2) reduction,and nitrogen reduction reactions).The persistent difficulties associated with conducting experimental synthesis and establishing artificial intelligence-based forecasts are extensively deliberated alongside the potential and forthcoming prospects of MBenes.This review provides a single platform for an overview of the MBene’s potential in energy storage and harvesting.展开更多
Carbon dioxide(CO_(2))emissions from the cement industry account for 26%of the total industrial emissions,and the need to develop low-carbon techniques within the cement industry is extremely urgent.Low-carbon project...Carbon dioxide(CO_(2))emissions from the cement industry account for 26%of the total industrial emissions,and the need to develop low-carbon techniques within the cement industry is extremely urgent.Low-carbon projects and technologies for the cement industry in different regions and countries have been thoroughly reviewed in this manuscript,and the low-carbon development concept for each county has been analyzed.For developing countries such as China and India,energy saving and efficiency enhancement are currently the key points,while for developed countries and regions such as Europe,more efforts have been focused on carbon capture,utilization,and storage(CCUS).Global CCUS projects have been previously conducted,and the majority of CCUS projects are currently performed in Europe where major projects such as the CEMCAP,CLEANKER,and IEILAC projects represent the latest research progress in cement production technologies and low-carbon technologies for the global cement industry.The development of low-carbon cement technologies has changed from focusing on the end point to instead focusing on the source and process through the exploration of hydrogen and solar energies,and more disruptive and original technologies are expected to be developed,particularly in the cement industry in China.展开更多
With the vigorous development of China's iron and steel industry and the introduction of ultra-low emission policies,the emission of pollutants such as SO_(2)and NO x has received unprecedented attention.Consideri...With the vigorous development of China's iron and steel industry and the introduction of ultra-low emission policies,the emission of pollutants such as SO_(2)and NO x has received unprecedented attention.Considering the increase of the proportion of semi-dry desulfurization technology in the desulfurization process,several semi-dry desulphurization technologies such as flue gas circulating fluidized bed(CFB),dense flow absorber(DFA)and spray drying absorption(SDA)are briefly summarized.Moreover,a method for simultaneous treatment of SO_(2)and NOx in sintering/pelletizing flue gas by O_(3)oxidation combined with semidry method is introduced.Meantime,the effects of key parameters such as O_(3)/NO molar ratio,Ca SO_(3),SO_(2),reaction temperature,Ca/(S+2 N)molar ratio,droplet size and approach to adiabatic saturation temperature(AAST)on denitrification and desulfurization are analyzed.Furthermore,the reaction mechanism of denitrification and desulfurization is further elucidated.Finally,the advantages and development prospects of the new technology are proposed.展开更多
Proper treatment of acidleaching tailings(ALTs)of vanadiumbearing stone coal minerals is of great urgency.One approach is adding it into the raw materials during the preparation of lightweight aggregate(LWA).But clay ...Proper treatment of acidleaching tailings(ALTs)of vanadiumbearing stone coal minerals is of great urgency.One approach is adding it into the raw materials during the preparation of lightweight aggregate(LWA).But clay is always needed.In this paper,another solid waste,red mud,was mixed with ALTs as a source of flux components instead of clay.Evaluation of the physical characteristics,morphological structures,as well as crystal phases during the sintering process were investigated.When their mixtures with a proper ratio were sintered at 1080℃,a glassy phase with certain viscosity was formed,and the gases generated simultaneously were encapsulated by the melt.Finally,LWA with a onehour water absorption as low as 1.46%,a bulk density as low as 728.76 kgm 3 and a compressive strength as high as 10.77 MPa was fabricated.展开更多
To reduce the power consumption and improve the mixing performance in stirred tanks,two improved disc turbines namely swept-back parabolic disc turbine(SPDT)and staggered fan-shaped parabolic disc turbine(SFPDT)are de...To reduce the power consumption and improve the mixing performance in stirred tanks,two improved disc turbines namely swept-back parabolic disc turbine(SPDT)and staggered fan-shaped parabolic disc turbine(SFPDT)are developed.After validation of computational fluid dynamics(CFD)model with experimental results,CFD simulations are carried out to study the flow pattern,mean velocity,power consumption,pumping capacity and mixing efficiency of the improved and traditional impellers in a dished-bottom tank under turbulent flow conditions,The results indicate that compared with the commonly used parabolic disc turbine(PDT),the power number of proposed SPDT and SFPDT impellers is reduced by 43%and 12%,and the pumping efficiency is increased by 68%and 13%,respectively.Furthermore,under the same power consumption(0-700 W·m^(-3)),the mixing performance of both SPDT and SFPDT is also superior to that of Rushton turbine and PDT.展开更多
The chemical utilization of CO_2 is a crucial step for the recycling of carbon resource. In recent years, the study on the conversion of CO_2 into a wide variety of C_(2+) important chemicals and fuels has received co...The chemical utilization of CO_2 is a crucial step for the recycling of carbon resource. In recent years, the study on the conversion of CO_2 into a wide variety of C_(2+) important chemicals and fuels has received considerable attention as an emerging technology. Since CO_2 is thermodynamically stable and kinetically inert, the effective activation of CO_2 molecule for the selective transformation to target products still remains a challenge. The welldesigned CO_2 reduction route and efficient catalyst system has imposed the feasibility of CO_2 conversion into C_(2+) chemicals and fuels. In this paper, we have reviewed the recent advances on chemical conversion of CO_2 into C_(2+) chemicals and fuels with wide practical applications, including important alcohols, acetic acid, dimethyl ether, olefins and gasoline. In particular, the synthetic routes for C\\C coupling and carbon chain growth, multifunctional catalyst design and reaction mechanisms are exclusively emphasized.展开更多
Decomposition kinetics of mullite and corundum in coal fly ash with highly alkaline solution was studied.The effects of the reaction temperature and reaction time on decomposition rates of mullite and corundum and alu...Decomposition kinetics of mullite and corundum in coal fly ash with highly alkaline solution was studied.The effects of the reaction temperature and reaction time on decomposition rates of mullite and corundum and alumina extraction efficiency were investigated.The results show that increasing reaction temperature and reaction time increases the decomposition rates of mullite and corundum and alumina extraction efficiency,with the decomposition temperature of mullite lower than that of corundum.After 90 min reaction at 220℃,more than 100 g alumina was extracted when recycling 1 L of alkaline solution.The decomposition processes of mullite and corundum corresponded with the shrinking unreacted core model,and the reaction rate was under chemical reaction control,with the activation energies of mullite and corundum being 67.46 and 161.82 kJ/mol,respectively.展开更多
A new method by liquid-liquid-liquid three phase system, consisting of acidified primary amine N1923 （abbreviated as A-N1923）, poly（ethylene glycol） （PEG） and （NH4）2S04 aqueous solution, was suggested for the ...A new method by liquid-liquid-liquid three phase system, consisting of acidified primary amine N1923 （abbreviated as A-N1923）, poly（ethylene glycol） （PEG） and （NH4）2S04 aqueous solution, was suggested for the separation and simultaneous extraction of Ⅴ（Ⅴ） and Cr（Ⅵ） from the acidic leach solutions of high- chromium vanadium-titanium magnetite. Experimental results indicated that Ⅴ（Ⅴ） and Cr（Ⅵ） could be selectively enriched into the A-N1923 organic top phase and PEG-rich middle phase, respectively, while AI（Ⅲ） and other co-existing impurity ions, such as Si（Ⅳ）, Fe（Ⅲ）, Ti（Ⅳ）, Mg（Ⅱ） and Ca（Ⅱ） in acidic leach solutions, could be enriched in the （NH4）2SO4 bottom aqueous phase. During the process for extraction and separation of Ⅴ（Ⅴ） and Cr（Ⅵ）, almost all of impurity ions could be removed. The separation factors between Ⅴ （Ⅴ） and Cr（Ⅵ） could reach 630 and 908, respectively in the organic top phase and PEG middle phase, and yields of recovered Ⅴ（Ⅴ） and Cr（Ⅵ） in the top phase and middle phase respectively were all above 90%. Various effects including aqueous pH, A-N1923 concentration, PEG added amount and （NH4）2SO4 concentration on three-phase partitioning of Ⅴ（Ⅴ） and Cr（Ⅵ） were discussed. It was found that the partition of Cr（Ⅵ） into the PEG-rich middle phase was driven by hydrophobic interaction, while extraction of Ⅴ（Ⅴ） by A-N1923 resulted of anion exchange between NO; and H2V10O4-28. Stripping of Ⅴ（Ⅴ） and Cr（Ⅵ） from the top organic phase and the middle PEG-rich phase were achieved by mixing respectively with NANO3 aqueous solutions and NaOH-（NH4）2SO4 solutions. The present work highlights a new approach for the extraction and purification of V and Cr from the complex multi-metal co-existing acidic leach solutions of high-chromium vanadium-titanium magnetite.展开更多
A new approach was suggested in present work for improving the separation between Pr(Ⅲ) and Nd(Ⅲ)by a so-called kinetic "push and pull" system consisting of [A336][NO3] and DTPA in a column extractor.It is...A new approach was suggested in present work for improving the separation between Pr(Ⅲ) and Nd(Ⅲ)by a so-called kinetic "push and pull" system consisting of [A336][NO3] and DTPA in a column extractor.It is revealed that,when organic extractant [A336][NO3] is continuously pumped into the column extractor in the form of dispersed oil droplets and at the same time DTPA was injected into the aqueous feed solution whet the extraction was just started,the separatiot factor of Pr(Ⅲ) to Nd(Ⅲ),βPr/Nd,increased obviously with the time,and could even achieve 21.7.Such an amazing increase in βPr/Nd value might be due to the extraction rate of Pr(Ⅲ) by [A336][NO3] oil droplets being faster than that of Nd(Ⅲ),while the complexing rate of Nd(Ⅲ) with DTPA in the aqueous solutions being faster than that of Pr(III).The opposite order of the two rates for Pr(Ⅲ) and Nd(Ⅲ) result in their kinetic "push and pull" separation.In contrast,the βPr/Nd value in traditional thermodynamic separation reported in previous literatures is only around 5 or even less,even though using the same extractant [A336][NO3] and DTPA but by previously adding DTPA into the aqueous feed solutions for pre-complexing of Pr(Ⅲ) and Nd(Ⅲ).Various effects from the pH and addition amount of DTPA aqueous solutions,LiNO3 concentrations in initial aqueous feed solutions,the initial concentration ratios of Pr(Ⅲ) to Nd(Ⅲ) ions,the initial pH of aqueous feed solutions,and the concentrations of [A336][NO3] in organic phases,on the kinetic separatiot of Pr(Ⅲ) and Nd(Ⅲ) are discussed.The present work highlights a promising approach for separation of rare earths or other targets with extreme similarity in physicochemical properties.展开更多
Titanium mineral was prepared from vanadium titanomagnetite concentrates by hydrogen reduction and acid leaching.The leaching behaviors of elements like Fe,V,Mn,Al,Mg,Ca,and Si were highly related to the reduction deg...Titanium mineral was prepared from vanadium titanomagnetite concentrates by hydrogen reduction and acid leaching.The leaching behaviors of elements like Fe,V,Mn,Al,Mg,Ca,and Si were highly related to the reduction degree.The phase compositions of the reduced materials and the leached residues were analyzed by XRD to identify the effect of reduction degree on the leaching mechanisms.The results showed that the concentrates were reduced to iron metal and titanomagnetite at 800-1000°C for 0.5 h,and the above elements of Fe and impurities were easily leached.Deeper reduction led to the formation of ilmenite and Mg-Al spinel,which hindered leaching.Mg-bearing anosovite appeared in the further reduced materials,and the leaching rates of impurities became much lower.An upgraded titanium mineral with a normalized TiO_(2) grade of 70.3%was achieved by H_(2) reduction at 850°C for 0.5 h and acid leaching,which is a satisfactory Ti resource for the preparation of titanium oxide by sulfate process.展开更多
The coupled CFD-E-model for multiphase micro-mixing was developed,and used to predict the micro-mixing effects on the parallel competing chemical reactions in semi-batch gas–liquid and solid–liquid stirred tanks.Bas...The coupled CFD-E-model for multiphase micro-mixing was developed,and used to predict the micro-mixing effects on the parallel competing chemical reactions in semi-batch gas–liquid and solid–liquid stirred tanks.Based on the multiphase macro-flow field,the key parameters of the micro-mixing E-model were obtained with solving the Reynolds-averaged transport equations of mixture fraction and its variance at low computational costs.Compared with experimental data,the multiphase numerical method shows the satisfactory predicting ability.For the gas–liquid system,the segregated reaction zone is mainly near the feed point,and shrinks to the exit of feed-pipe when the feed position is closer to the impeller.Besides,surface feed requires more time to completely exhaust the added H+solution than that of impeller region feed at the same operating condition.For the solid–liquid system,when the solid suspension cloud is formed at high solid holdups,the flow velocity in the clear liquid layer above the cloud is notably reduced and the reactions proceed slowly in this almost stagnant zone.Therefore,the segregation index in this case is larger than that in the dilute solid–liquid system.展开更多
基金supported by the National Key R&D Program of China(No.2023YFC3709500).
文摘Global warming caused by the emission of CO_(2) in industrial flue gas has attractedmore and more attention.Therefore,to fix CO_(2) with high efficiency and environmentally friendly had become the hot research field.Compared with the traditional coal-fired power plant flue gas emission reduction technology,carbon fixation and emission reduction by microalgae is considered as a promising technology due to the advantages of simple process equipment,convenient operation and environmental protection.When the flue gas is treated by microalgae carbon fixation and emission reduction technology,microalgae cells can fix CO_(2) in the flue gas through photosynthesis,and simultaneously absorb NO_(x) and SO_(x) as nitrogen and sulfur sources required for growth.Meanwhile,they can also absorb mercury,selenium,arsenic,cadmium,lead and other heavy metal ions in the flue gas to obtain microalgae biomass.The obtained microalgae biomass can be further transformed into high valueadded products,which has broad development prospects.This paper reviews the mechanisms and pathways of CO_(2) sequestration,the mechanism and impacts of microalgal emission reduction of flue gas pollutants,and the applications of carbon sequestration in industrial flue gas by microalgae.Finally,this paper provides some guidelines and prospects for the research and application of green emission reduction technology for industrial flue gas.
基金partially funded by the National Natural Science Foundation of China(52074255,52274412)。
文摘Silicon nanowires(SiNWs)have been used in a wide variety of applications over the past few decades due to their excellent material properties.The only drawback is the high production cost of SiNWs.The preparation of SiNWs from photovoltaic waste silicon(WSi)powders,which are high-volume industrial wastes,not only avoids the secondary energy consumption and environmental pollution caused by complicated recycling methods,but also realizes its high-value utilization.Herein,we present a method to rapidly convert photovoltaic WSi powders into SiNWs products.The flash heating and quenching provided by carbothermal shock induce the production of free silicon atoms from the WSi powders,which are rapidly reorganized and assembled into SiNWs during the vapor-phase process.This method allows for the one-step composite of SiNWs and carbon cloth(CC)and the formation of SiC at the interface of the silicon(Si)and carbon(C)contact to create a stable chemical connection.The obtained SiNWs-CC(SiNWs@CC)composites can be directly used as lithium anodes,exhibiting high initial coulombic efficiency(86.4%)and stable cycling specific capacity(2437.4 mA h g^(-1)at 0.5 A g^(-1)after 165 cycles).In addition,various SiNWs@C composite electrodes are easily prepared using this method.
基金supported by National Natural Science Foundation of China(22178081)Interdisciplinary Research Program of Natural Science of Hebei University(No.DXK202116)+1 种基金Functional Pharmaceutical Chromatographic Materials Innovation Team(605020521006)High-level Talents Introduction Program of Hebei University。
文摘Acrylic acid(AA)is an important and widely used industrial chemical,but its high toxicity renders its use incompatible with the concept of green development.By leveraging its terminal carboxyl group and unsaturated bond,we designed and explored a new strategy to increase the greenness of AA via its eutectic melting using a quaternary ammonium salt(choline chloride)to form a deep eutectic solvent(DES),followed by polymerisation of the DES to form a polymer(poly(DES)).The greenness of AA,DES,and poly(DES)was evaluated via an in vitro test using MGC80-3 cells and an in vivo test using Kunming mice.The toxicity improved from Grade 2(moderately toxic)for AA to Grade 1(slightly toxic)for DESs and Grade 0(non-toxic)for poly(DES)in the in vitro test.Moreover,the poly(DES)s showed a lower toxicity in mice than the DESs in the in vivo test.Thus,greenness enhancement was successfully achieved,with the greenness following the order AA<DES<poly(DES).Furthermore,the mechanisms underlying the change in toxicity were explored through microscopy and flow cytometry,which revealed that the DES can permeate the MGC80-3 cell membrane during the G_(0)/G_(1) phase to adversely affect DNA synthesis in the S phase,but the poly(DES)cannot.Finally,the green poly(DES),which showed good adsorption properties and flexible functionality,was successfully applied as a carrier or excipient of drugs.Through the novel strategy reported herein,greenness enhancement and the broadening of the application scope of a toxic organic acid were achieved,making such acids applicable for green development.
基金financially supported by the Key Project of Research and Development Plan of Jiangxi Province(Nos.20223BBG74006 and 20201BBE51007)the National Science Foundation of China(No.52060018)the National Science Fund for Distinguished Young Scholars(No.52125002)。
文摘The efficient and environmentally friendly recycling technology of waste residue that including abundant heavy metal produced during the recovery of lithium batteries has become a research hotspot.Herein,a novelty process of acid leaching-selective electrodeposition-deep impurity removal-regeneration was proposed to recovery of the CuS slag,which has been efficient transferred to high purity cathode copper and commercially available ternary precursors.Copper cathode with a purity of 99.67%was prepared under electrochemical reaction conditions at-0.55 V for 2 h.A novel impurity remover-Mn powder,which was used to remove the residual impurities and as a feedstock for the ternary precursor.Finally,NCM523 was regenerated by co-precipitation.The process is superior to the traditional process in economy,energy consumption,CO_(2)emissions,product purity and process duration.This study provides a new approach for solid waste recovery and precious metal enrichment.
基金supported by the National Nature Science Foundation of China(21878315 and 21808223)National Key Research and Development Program of China(2017YFA0206803)+3 种基金Innovation Academy for Green ManufactureCAS(IAGM2020C17)K.C.Wong Education Foundation(GJTD-2018-04)。
文摘A double-effect reactive distillation(DERD)process was proposed for the production of propylene glycol methyl ether from propylene oxide and methanol to overcome the shortcoming of low selectivity and high-energy consumption in the tubular plug-flow reactor.A single-column reactive distillation(RD)process was conducted under optimized operating conditions based on sensitivity analysis as a reference.The results demonstrated that the proposed DERD process is able to achieve more than 95%selectivity of the desired product.After that,a design approach of the DERD process with an objective of the minimum operating cost was proposed to achieve further energy savings in the RD process.The proposed DERD configuration can provide a large energy-savings by totally utilization of the overhead vapor steam in the high-pressure RD column.A comparison of the single-column RD process revealed that the proposed DERD process can reduce the operating cost and the total annual cost of 25.3%and 30.7%,respectively,even though the total capital cost of DERD process is larger than that of the RD process.
基金supported by the National Key Research and Development Program of China(No.2023YFC2908304).
文摘Vanadium is a strategic metal in many countries,and it is mainly extracted from vanadium slag produced in titanomagnetite metallurgy.The traditional sodium roasting process for vanadium extraction poses environmental threats,and a green calcification pro-cess has been proposed.However,the vanadium extraction rate in the calcification process is much lower than in the sodium roasting pro-cess,which is related to vanadium solid solubility in Fe_(2)TiO_(5).Previous studies about vanadium behavior in Fe_(2)TiO_(5) were conducted in air,with a vanadium oxidation state of V5+.Vanadium with lower oxidation states has been detected in the tailings in the calcification process.The present paper studied the effects of vanadium oxidation states on the solid solubility in Fe_(2)TiO_(5) through solid-state reaction,X-ray diffraction characterization,transmission electron microscopy characterization,X-ray photoelectron spectroscopy analysis,and solid solu-tion modeling.The relative interaction values between vanadium oxides and Fe_(2)TiO_(5) are obtained as|L_(V_(2)O_(3))|>|L_(V_(2)O_(4))|>|L_(V_(2)O_(5)),indicating that vanadium with lower valence is preferable to be solid dissolved in Fe_(2)TiO_(5).The results imply that insufficiently oxidized vanadium increases the vanadium content in the Fe_(2)TiO_(5) phase during vanadium slag’s calcification roasting.Besides,experimental conditions op-timization shows that higher experimental temperature,vanadium introduction as V2O3,and a high-purity argon atmosphere would lead to higher vanadium solubility in Fe_(2)TiO_(5),and high temperature is beneficial for the release of vanadium from vanadium-containing Fe_(2)TiO_(5) when dissociated in air.
基金the support the National Natural Science Foundation of China(5210440)S&T Program of Hebei(23311501D)Program of HBIS Group under HG2023222。
文摘In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by ion morphology pretreatme nt and solvent extraction.An acidic V(Ⅴ)/W(Ⅵ)solution was obtained using the me mbrane electrolysis method without adding any other chemical reagents.In addition,Na was recovered in the form of NaOH by product,avoiding the generation of Na containing wastewater.The electrolysis parameters were investigated,the lowest power consumption of 3063 kW·h·t^(-1)NaOH was obtained at a current density of 125 A·m^(-2)and an initial NaOH concentration of 2 mol·L^(-1).After electrolysis,oxalic acid was added to the acidic V/W containing solution,converting V(Ⅴ)negative ion to V(Ⅳ)positive ion.Since W(Ⅵ)ion state remained in negative form,the generation of heteropolyacid ions(W_(x)V_(y)O_(z)^(n-))was prevented.It was found that under the condition of oxalic acid addition/theoretical consumption 1.2 and reaction temperature 75℃,100%V(Ⅴ)was co nverted to V(Ⅳ4).Using 10%N263+10%noctanol+80%sulfonated kerosene as extractant,the highest W(Ⅵ)/V(Ⅳ)separation coefficient of 7559.76was obtained at pH=1.8,O:A ratio=1:1 and extraction time 15 min.With 2 mol·L^(-1)NaOH as stripping reagent,the W stripping efficiency reached 98.50%at O:A ratio=2:1 after 4-stages of stripping.The enrichment of V remained in the solution was realized using P204 as extractant and 20%(mass)H_(2)SO_(4)as stripping reagent.The parameters of extraction/stripping process were investigated,using 10%P204+10%TBP+80%sulfonated kerosene as extractant,the V extraction efficiency reached 97.50%at O:A ratio=1:2after 4 stages of extraction.Using 20%H_(2)SO_(4)as the stripping reagent,the V stripping efficiency was 98.30%at an O:A ratio of 4:1 after five stage s of stripping.After the entire process,a high-purity VOSO_(4)and Na_(2)WO_(4)product solutions were obtained with V/W recovery efficiency 95.84%/98.50%,separately.This study examined a more effective and cleaner method for separating V/W/Na in Na_(2)WO_(4)/NaVO_(3)solution,which may serve as a reference for the separation and recovery of V/W/Na in waste SCR catalysts.
基金National Natural Science Foundation of China(22178228,22178326)
文摘A cylindrical chamber with a rotating bottom holds significant potential for application in cell culture bioreactors due to its ability to generate more stable swirling flows.In order to control vortex breakdown within the chamber,this study first establishes a computational fluid dynamics simulation coupled with the level set method.Verified by experimental results in literature,this method accurately simulates the position and shape of vortex breakdown,and also predicts the critical Reynolds numbers for the appearance and detachment of vortex breakdown bubbles from the center.Additionally,it precisely captures the gas-liquid interface and depicts the vortex breakdown phenomenon in the air above the liquid for the first time.Finally,it predicts the impact of physical property of gas-liquid systems on vortex breakdown in response to significant changes in viscosity of microbial process systems.
基金supported by the National Key Research and Development Program of China(2022YFB3504702)support from Horizon-EIC,Pathfinder challenges(101070976)+3 种基金support from the National Natural Science Foundation of China(22278402,22478389)the Key Research and Development Program of Henan Province(231111241800)State Key Laboratory of Mesoscience and Engineering(MESO-23-A08)the Frontier Basic Research Projects of Institute of Process Engineering,CAS(QYJC-2023-03).
文摘Ionic liquids (ILs) and deep eutectic solvents (DESs) as green solvents have attracted dramatic attention recently due to their highly tunable properties. However, traditional experimental screening methods are inefficient and resource-intensive. The article provides a comprehensive overview of various ML algorithms, including artificial neural network (ANN), support vector machine (SVM), random forest (RF), and gradient boosting trees (GBT), etc., which have demonstrated exceptional performance in handling complex and high-dimensional data. Furthermore, the integration of ML with quantum chemical calculations and conductor-like screening model-real solvent (COSMO-RS) has significantly enhanced predictive accuracy, enabling the rapid screening and design of novel solvents. Besides, recent ML applications in the prediction and design of ILs and DESs focused on solubility, melting point, electrical conductivity, and other physicochemical properties become more and more. This paper emphasizes the potential of ML in solvent design, overviewing an efficient approach to accelerate the development of sustainable and high-performance materials, providing guidance for their widespread application in a variety of industrial processes.
基金supported by the National Natural Science Foundation of China(No.52302241 and 22225801)the Major Science and Technology Programs of Henan Province(241100240200)the China Postdoctoral Science Foundation(No.2023M730940).
文摘MXene derivatives are notable two-dimensional nanomaterials with numerous prospective applications in the domains of energy development.MXene derivative,MBene,diversifies its focus on energy storage and harvesting due to its exceptional electrical conductivity,structural flexibility,and mechanical properties.This comprehensive review describes the sandwich-like structure of the synthesized MBene,derived from its multilayered parent material and its distinct chemical framework to date.The fields of focus encompass the investigation of novel MBenes,the study of phase-changing mechanisms,and the examination of hex-MBenes,ortho-MBenes,tetra-MBenes,tri-MBenes,and MXenes with identical transition metal components.A critical analysis is also provided on the electrochemical mechanism and performance of MBene in energy storage(Li/Na/Mg/Ca/Li–S batteries and supercapacitors),as well as conversion and harvesting(CO_(2) reduction,and nitrogen reduction reactions).The persistent difficulties associated with conducting experimental synthesis and establishing artificial intelligence-based forecasts are extensively deliberated alongside the potential and forthcoming prospects of MBenes.This review provides a single platform for an overview of the MBene’s potential in energy storage and harvesting.
基金supported by the National Natural Science Foundation of China (No.52170119)the Youth Innovation Promotion Association of the Chinese Academy of Sciences (No.2021044)。
文摘Carbon dioxide(CO_(2))emissions from the cement industry account for 26%of the total industrial emissions,and the need to develop low-carbon techniques within the cement industry is extremely urgent.Low-carbon projects and technologies for the cement industry in different regions and countries have been thoroughly reviewed in this manuscript,and the low-carbon development concept for each county has been analyzed.For developing countries such as China and India,energy saving and efficiency enhancement are currently the key points,while for developed countries and regions such as Europe,more efforts have been focused on carbon capture,utilization,and storage(CCUS).Global CCUS projects have been previously conducted,and the majority of CCUS projects are currently performed in Europe where major projects such as the CEMCAP,CLEANKER,and IEILAC projects represent the latest research progress in cement production technologies and low-carbon technologies for the global cement industry.The development of low-carbon cement technologies has changed from focusing on the end point to instead focusing on the source and process through the exploration of hydrogen and solar energies,and more disruptive and original technologies are expected to be developed,particularly in the cement industry in China.
基金supported by the National Key Research and Development Program of China(No.2017YFC0210600)the National Natural Science Foundation of China(No.51978644)。
文摘With the vigorous development of China's iron and steel industry and the introduction of ultra-low emission policies,the emission of pollutants such as SO_(2)and NO x has received unprecedented attention.Considering the increase of the proportion of semi-dry desulfurization technology in the desulfurization process,several semi-dry desulphurization technologies such as flue gas circulating fluidized bed(CFB),dense flow absorber(DFA)and spray drying absorption(SDA)are briefly summarized.Moreover,a method for simultaneous treatment of SO_(2)and NOx in sintering/pelletizing flue gas by O_(3)oxidation combined with semidry method is introduced.Meantime,the effects of key parameters such as O_(3)/NO molar ratio,Ca SO_(3),SO_(2),reaction temperature,Ca/(S+2 N)molar ratio,droplet size and approach to adiabatic saturation temperature(AAST)on denitrification and desulfurization are analyzed.Furthermore,the reaction mechanism of denitrification and desulfurization is further elucidated.Finally,the advantages and development prospects of the new technology are proposed.
文摘Proper treatment of acidleaching tailings(ALTs)of vanadiumbearing stone coal minerals is of great urgency.One approach is adding it into the raw materials during the preparation of lightweight aggregate(LWA).But clay is always needed.In this paper,another solid waste,red mud,was mixed with ALTs as a source of flux components instead of clay.Evaluation of the physical characteristics,morphological structures,as well as crystal phases during the sintering process were investigated.When their mixtures with a proper ratio were sintered at 1080℃,a glassy phase with certain viscosity was formed,and the gases generated simultaneously were encapsulated by the melt.Finally,LWA with a onehour water absorption as low as 1.46%,a bulk density as low as 728.76 kgm 3 and a compressive strength as high as 10.77 MPa was fabricated.
基金supported by the National Key Research and Development Program(2020YFA0906800)the National Natural Science Foundation of China(22078325,21938009)+3 种基金the NSFC-EU project(31961133018)the Special Project of Strategic Leading Science and Technology CAS(XDC06010302)Chemistry and Chemical Engineering Guangdong Laboratory,Shantou(No.1922006)the Li Foundation Fellow Program。
文摘To reduce the power consumption and improve the mixing performance in stirred tanks,two improved disc turbines namely swept-back parabolic disc turbine(SPDT)and staggered fan-shaped parabolic disc turbine(SFPDT)are developed.After validation of computational fluid dynamics(CFD)model with experimental results,CFD simulations are carried out to study the flow pattern,mean velocity,power consumption,pumping capacity and mixing efficiency of the improved and traditional impellers in a dished-bottom tank under turbulent flow conditions,The results indicate that compared with the commonly used parabolic disc turbine(PDT),the power number of proposed SPDT and SFPDT impellers is reduced by 43%and 12%,and the pumping efficiency is increased by 68%and 13%,respectively.Furthermore,under the same power consumption(0-700 W·m^(-3)),the mixing performance of both SPDT and SFPDT is also superior to that of Rushton turbine and PDT.
基金Supported by the National Natural Science Foundation of China(21576272,21476244)"Transformational Technologies for Clean Energy and Demonstration"+2 种基金Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA21030600)the project from Jiangsu Collaborative Innovation Center for Ecological Building Materials and Environmental Protection Equipment(YCXT201607)Youth Innovation Promotion Association(2016046)of CAS
文摘The chemical utilization of CO_2 is a crucial step for the recycling of carbon resource. In recent years, the study on the conversion of CO_2 into a wide variety of C_(2+) important chemicals and fuels has received considerable attention as an emerging technology. Since CO_2 is thermodynamically stable and kinetically inert, the effective activation of CO_2 molecule for the selective transformation to target products still remains a challenge. The welldesigned CO_2 reduction route and efficient catalyst system has imposed the feasibility of CO_2 conversion into C_(2+) chemicals and fuels. In this paper, we have reviewed the recent advances on chemical conversion of CO_2 into C_(2+) chemicals and fuels with wide practical applications, including important alcohols, acetic acid, dimethyl ether, olefins and gasoline. In particular, the synthetic routes for C\\C coupling and carbon chain growth, multifunctional catalyst design and reaction mechanisms are exclusively emphasized.
基金Project(2013CB632601)supported by the National Basic Research Program of China
文摘Decomposition kinetics of mullite and corundum in coal fly ash with highly alkaline solution was studied.The effects of the reaction temperature and reaction time on decomposition rates of mullite and corundum and alumina extraction efficiency were investigated.The results show that increasing reaction temperature and reaction time increases the decomposition rates of mullite and corundum and alumina extraction efficiency,with the decomposition temperature of mullite lower than that of corundum.After 90 min reaction at 220℃,more than 100 g alumina was extracted when recycling 1 L of alkaline solution.The decomposition processes of mullite and corundum corresponded with the shrinking unreacted core model,and the reaction rate was under chemical reaction control,with the activation energies of mullite and corundum being 67.46 and 161.82 kJ/mol,respectively.
基金Supported by the National Basic Research and Development Program of China(973ProgramNo.2013CB632602)the National Natural Science Foundation of China(Nos.51574213,51074150)
文摘A new method by liquid-liquid-liquid three phase system, consisting of acidified primary amine N1923 （abbreviated as A-N1923）, poly（ethylene glycol） （PEG） and （NH4）2S04 aqueous solution, was suggested for the separation and simultaneous extraction of Ⅴ（Ⅴ） and Cr（Ⅵ） from the acidic leach solutions of high- chromium vanadium-titanium magnetite. Experimental results indicated that Ⅴ（Ⅴ） and Cr（Ⅵ） could be selectively enriched into the A-N1923 organic top phase and PEG-rich middle phase, respectively, while AI（Ⅲ） and other co-existing impurity ions, such as Si（Ⅳ）, Fe（Ⅲ）, Ti（Ⅳ）, Mg（Ⅱ） and Ca（Ⅱ） in acidic leach solutions, could be enriched in the （NH4）2SO4 bottom aqueous phase. During the process for extraction and separation of Ⅴ（Ⅴ） and Cr（Ⅵ）, almost all of impurity ions could be removed. The separation factors between Ⅴ （Ⅴ） and Cr（Ⅵ） could reach 630 and 908, respectively in the organic top phase and PEG middle phase, and yields of recovered Ⅴ（Ⅴ） and Cr（Ⅵ） in the top phase and middle phase respectively were all above 90%. Various effects including aqueous pH, A-N1923 concentration, PEG added amount and （NH4）2SO4 concentration on three-phase partitioning of Ⅴ（Ⅴ） and Cr（Ⅵ） were discussed. It was found that the partition of Cr（Ⅵ） into the PEG-rich middle phase was driven by hydrophobic interaction, while extraction of Ⅴ（Ⅴ） by A-N1923 resulted of anion exchange between NO; and H2V10O4-28. Stripping of Ⅴ（Ⅴ） and Cr（Ⅵ） from the top organic phase and the middle PEG-rich phase were achieved by mixing respectively with NANO3 aqueous solutions and NaOH-（NH4）2SO4 solutions. The present work highlights a new approach for the extraction and purification of V and Cr from the complex multi-metal co-existing acidic leach solutions of high-chromium vanadium-titanium magnetite.
基金supported by the National Natural Science Foundation of China(51574213,51074150)the Key Project of Chinese National Programs for Fundamental Research and Development(973 Program)(2012CBA01203).
文摘A new approach was suggested in present work for improving the separation between Pr(Ⅲ) and Nd(Ⅲ)by a so-called kinetic "push and pull" system consisting of [A336][NO3] and DTPA in a column extractor.It is revealed that,when organic extractant [A336][NO3] is continuously pumped into the column extractor in the form of dispersed oil droplets and at the same time DTPA was injected into the aqueous feed solution whet the extraction was just started,the separatiot factor of Pr(Ⅲ) to Nd(Ⅲ),βPr/Nd,increased obviously with the time,and could even achieve 21.7.Such an amazing increase in βPr/Nd value might be due to the extraction rate of Pr(Ⅲ) by [A336][NO3] oil droplets being faster than that of Nd(Ⅲ),while the complexing rate of Nd(Ⅲ) with DTPA in the aqueous solutions being faster than that of Pr(III).The opposite order of the two rates for Pr(Ⅲ) and Nd(Ⅲ) result in their kinetic "push and pull" separation.In contrast,the βPr/Nd value in traditional thermodynamic separation reported in previous literatures is only around 5 or even less,even though using the same extractant [A336][NO3] and DTPA but by previously adding DTPA into the aqueous feed solutions for pre-complexing of Pr(Ⅲ) and Nd(Ⅲ).Various effects from the pH and addition amount of DTPA aqueous solutions,LiNO3 concentrations in initial aqueous feed solutions,the initial concentration ratios of Pr(Ⅲ) to Nd(Ⅲ) ions,the initial pH of aqueous feed solutions,and the concentrations of [A336][NO3] in organic phases,on the kinetic separatiot of Pr(Ⅲ) and Nd(Ⅲ) are discussed.The present work highlights a promising approach for separation of rare earths or other targets with extreme similarity in physicochemical properties.
基金financially supported by the Beijing Natural Science Foundation, China (No. 2192056)the National Natural Science Foundation of China (No. 51771179)+1 种基金the National Key R&D Program of China (No. 2018YFC1900505)The financial supports from the Youth Innovation Promotion Association CAS and the CAS Interdisciplinary Innovation Team
文摘Titanium mineral was prepared from vanadium titanomagnetite concentrates by hydrogen reduction and acid leaching.The leaching behaviors of elements like Fe,V,Mn,Al,Mg,Ca,and Si were highly related to the reduction degree.The phase compositions of the reduced materials and the leached residues were analyzed by XRD to identify the effect of reduction degree on the leaching mechanisms.The results showed that the concentrates were reduced to iron metal and titanomagnetite at 800-1000°C for 0.5 h,and the above elements of Fe and impurities were easily leached.Deeper reduction led to the formation of ilmenite and Mg-Al spinel,which hindered leaching.Mg-bearing anosovite appeared in the further reduced materials,and the leaching rates of impurities became much lower.An upgraded titanium mineral with a normalized TiO_(2) grade of 70.3%was achieved by H_(2) reduction at 850°C for 0.5 h and acid leaching,which is a satisfactory Ti resource for the preparation of titanium oxide by sulfate process.
基金supported by the National Key Research and Development Program(2016YFB0301702)the National Natural Science Foundation of China(21808221,21776282,21938009)+3 种基金Major Research Plan of NSFC(91934301)the Key Research Program of Frontier Sciences,CAS(QYZDJ-SSW-JSC030)the Key Research Program of Nanjing IPE Institute of Green Manufacturing Industry(No.E0010719)the Youth Innovation Promotion Association CAS。
文摘The coupled CFD-E-model for multiphase micro-mixing was developed,and used to predict the micro-mixing effects on the parallel competing chemical reactions in semi-batch gas–liquid and solid–liquid stirred tanks.Based on the multiphase macro-flow field,the key parameters of the micro-mixing E-model were obtained with solving the Reynolds-averaged transport equations of mixture fraction and its variance at low computational costs.Compared with experimental data,the multiphase numerical method shows the satisfactory predicting ability.For the gas–liquid system,the segregated reaction zone is mainly near the feed point,and shrinks to the exit of feed-pipe when the feed position is closer to the impeller.Besides,surface feed requires more time to completely exhaust the added H+solution than that of impeller region feed at the same operating condition.For the solid–liquid system,when the solid suspension cloud is formed at high solid holdups,the flow velocity in the clear liquid layer above the cloud is notably reduced and the reactions proceed slowly in this almost stagnant zone.Therefore,the segregation index in this case is larger than that in the dilute solid–liquid system.
