CaO-based heat carriers have shown great prospects for thermochemical energy storage in concentrated solar power systems due to the features such as rich reserves,environmental safety,high energy storage densities and...CaO-based heat carriers have shown great prospects for thermochemical energy storage in concentrated solar power systems due to the features such as rich reserves,environmental safety,high energy storage densities and high operation temperatures.However,the density decay because of sintering and poor direct solar absorption of white CaO based heat carriers are the two main obstacles lying on the way to the realistic applications.This work introduced dark Mn-based inert support into calcium heat carriers,attempting to solve the above problems simultaneously.As an inert support,the finely dispersed Ca_(2)MnO_(4) functioned as the metal framework to resist CaCO_(3)/CaO sintering.Consequently,the cyclic stability of CaO-based heat carriers,resulting in the high energy storage densities of~2000 kJ/kg even over 20 cycles.As a dark material,Ca_(2)MnO_(4) successfully darkened CaO-based heat carriers,thereby greatly enhanced the direct solar absorption.In addition,the granulation of CaO-based heat carriers was also studied.The pellets showed satisfactory attrition resistance with only 9.85 wt% mass loss over 3200 cycles.In general,good physicochemical performance of Mn-doped CaO-based heat carrier endows it with great prospects for solar energy storage.展开更多
Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfur...Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfurization activity of nanosized Ce-ZnO had improved greatly,compared to nanosized ZnO desulfurizer.Nanosized Ce-ZnO desulfurizer was characterized by XRD,TPD-MS,XPS,and TEM.The research results indicated that doping Ce decreased the particle size of the nanosized ZnO desulfurizer and ZnS was the principal desulfurization product.There were adsorption complexes of HS and S on the surface of desulfurizer as well.Only a small amount of vapor appeared in the tail gas on the condition of meeting the precision of desulfurization.展开更多
CaO-Al2O3-SiO2-CaF2-MgO was selected as the slag system for desulfurization in LF process.The reaction between steel and slag during desulfurization has been simulated by using Factsage software to study the influence...CaO-Al2O3-SiO2-CaF2-MgO was selected as the slag system for desulfurization in LF process.The reaction between steel and slag during desulfurization has been simulated by using Factsage software to study the influence of component on the sulfur distribution ratio.In order to research the influence of CaO content,aluminum powder content and its granularity on desulfurization,laboratory experiments have been carried out in a 200 kg inductive furnace.Results showed that the optimal composition of deep desulfurizer is wCaO=64% and aluminium powder 10% with a granularity of 30 μm.Industrial trials showed that the main composition range of final slag in LF process is wCaO=53.0%-57.0%,wAl2O3=23.4%-25.1%,wSiO2=8.1%-10.0%,and wCaF2=3.2%-4.7%.The sulfur mass percent in steel is lower than 0.0008% with a desulfurization rate above 89%.According to the result of industrial production,this desulfurizer could meet the production requirement for ultra-low sulfur steel,of which sulfur mass percent is under 0.0015%展开更多
It is found that strong basic oxides including Li2O,Na2O,K2O and BaO,which are used to replace a part of CaO in CaO-based fluxes,can lower the melting point and the viscosity and enhance the dephosphorizing ability. T...It is found that strong basic oxides including Li2O,Na2O,K2O and BaO,which are used to replace a part of CaO in CaO-based fluxes,can lower the melting point and the viscosity and enhance the dephosphorizing ability. The mechanism was analysed and the addition of Li2O to CaO based fluxes was recommended.展开更多
B2O3 is selected as fluxing agent of CaO-based ladle refining slag to decrease the melting temperature as well as to improve the speed of slag forming and the refining efficiency. The effects of B2O3 on the melting te...B2O3 is selected as fluxing agent of CaO-based ladle refining slag to decrease the melting temperature as well as to improve the speed of slag forming and the refining efficiency. The effects of B2O3 on the melting temperature of two series of refining slags including the low basicity slags （the mass ratio of CaO/SiO2 is 3--4） and the high basicity slags （the mass ratio of CaO/SiO2 is 5--8.75） were investigated. The slag melting temperature was meas- ured using the hemisphere method. The results indicate that the fluxing action of B2O3 is better than that of CaF2 and A1203. For the CaO-based refining slag with low basicity, the melting temperature is decreased effectively when B2O3 is used to substitute for equal mass of CaF2, Al2O3 and SiO2, respectively. For the CaO-based refining slag with high basicity, when CaF2 is substituted by B2 03, the melting temperature can be decreased remarkably. Espe- cially, when the mass ratios of CaO/Al2O3 and CaO/SiO2 are in the range of 1.1--4.0 and 5.25--8. 0, respectively, the slag melting temperature is lower than 1 300 ℃. Therefore, the 132 03-containing refining slags with high ratios of CaO/Al2O3 and CaO/SiO2 have ultra low melting temperature.展开更多
High-temperature pyrolysis technology can effectively solve the problem of municipal solid waste pollution.However,the pyrolysis gas contains a large amount of CO_(2),which would adversely affect the subsequent utiliz...High-temperature pyrolysis technology can effectively solve the problem of municipal solid waste pollution.However,the pyrolysis gas contains a large amount of CO_(2),which would adversely affect the subsequent utilization.To address this problem,a novel method of co-precipitation modification with Ca,Mg and Zr metals was proposed to improve the CO_(2)capture performance.X-ray diffraction(XRD)patterns and energy dispersive X-ray spectroscopy analysis showed that the two inert supports MgO and CaZrO_(3)were uniformly distributed in the modified calcium-based sorbents.In addition,the XRD results indicated that CaZrO_(3)was produced by the reaction of ZrO_(2)and CaO at high temperatures.The effects of doping ratios,adsorption temperature,calcination temperature,CO_(2)concentration and calcination atmosphere on the adsorption capacity and cycle stability of the modified calcium-based sorbent were studied.The modified calcium-based sorbent achieved the best CO_(2)capture performance when the doping ratio was 10:1:1 with carbonation at 700℃ under 20%CO_(2)/80%N_(2)atmosphere and calcination at 900℃ under100%N_(2)atmosphere.After ten cycles,the average carbonation conversion rate of Ca-10 sorbent was 72%.Finally,the modified calcium-based sorbents successfully reduced the CO_(2)concentration of the pyrolysis gas from 37%to 5%.展开更多
Low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance ...Low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance desulfurizers.In this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative humidities.The results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional desulfurizers.Also,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration performance.Sufficient contact with the nascent surface maximizes the formation of slaked lime.The experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative humidity.Compared with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional desulfurizers.This work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.展开更多
CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In ...CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate(CaAc_2), which was doped with different elements(Mg, Al,Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer(TGA). The sorbents were characterized by N_2 isothermal adsorption measurements, scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO–Al, CaO–Ce and CaO–La were above 96.2%. After 110 cycles, the cyclic stability of CaO–Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.展开更多
In this experiment,an EG/ChCl deep eutectic solvent(DES)was synthesized using choline chloride(ChCl)and ethylene glycol(EG)as the raw materials.The synthesized DES was characterized by Fourier transform infrared spect...In this experiment,an EG/ChCl deep eutectic solvent(DES)was synthesized using choline chloride(ChCl)and ethylene glycol(EG)as the raw materials.The synthesized DES was characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.The results demonstrate the successful synthesis of DES.A certain amount of FeCl_(3) and CuSO_(4) was added to the DES to promote the absorption of H_(2)S;thus,a Fe(Ⅲ)-Cu(Ⅱ)coupled DES desulfurization system was obtained.The effects of DES raw materials’ratio,FeCl_(3) concentration,water content,CuSO_(4) concentration,and reaction temperature on the desulfurization efficiency and the regeneration conditions were studied.The results show that ChCl/EG DES with a molar ratio of 1:2 has a better desulfurization effect,and the addition of an appropriate amount of water can effectively promote the dissolution of CuSO_(4) and the absorption of H_(2)S.An appropriate increase in reaction temperature and CuSO_(4) concentration would also promote the absorption of H_(2)S.When the concentration of CuSO_(4) in DES desulfurizer was 0.15 mol/L,the gas speed was 20 mL/min,and the sulfur capacity could reach 10.23 g/L.The desulfurizer could be regenerated by passing O_(2),and the desulfurization efficiency did not change much after repeated use of desulfurization-regeneration many times.The desulfurization product was characterized by XRD as rhombohedral sulfur.展开更多
Sulfur dioxide is one of the major pollutants resulting from fuel combustion. In this study, CaO and attapulgite were utilized as raw material for synthesizing CaO/attapulgite (CaO/ATP) desulfurizer. The physicochemic...Sulfur dioxide is one of the major pollutants resulting from fuel combustion. In this study, CaO and attapulgite were utilized as raw material for synthesizing CaO/attapulgite (CaO/ATP) desulfurizer. The physicochemical characteristics of CaO/ATP desulfurizer were evaluated by various techniques such as XRD, SEM, FT-IR. The performance of samples was studied in dynamic conditions. Major factors affecting on desulfurization such as weight ratio of CaO to total, types of modifiers, roasting time and temperature were investigated. The desulfurization agent synthesized under optimal synthesis conditions with CaO content of 30 wt% and NaOH modifier, and the desulfurization roasting time of 2 hours and roasting temperature of 600°C, exhibit sulfur tolerance of 10.15 wt%. This desulfurizer with excellent absorbency and catalysis of desulfurization, economical and?environment-friendly, could be especially useful in industrial applications.展开更多
The CaO-based pellets were fabricated using extrusion-spheronization method for calcium looping thermochemical heat storage under the fluidization.The effects of adhesive,biomass-based pore-forming agent,binder and pa...The CaO-based pellets were fabricated using extrusion-spheronization method for calcium looping thermochemical heat storage under the fluidization.The effects of adhesive,biomass-based pore-forming agent,binder and particle size on the heat storage performance and mechanical property of the CaObased pellets were investigated in a bubbling fluidized bed reactor.The addition of 2%(mass)polyvinylpyrrolidone as an adhesive not only helps granulate,but also improves the heat storage capacity of the pellets.All biomass-templated CaO-based pellets display higher heat storage capacity than biomass-free pellets,indicating that the biomass-based pore-forming agent is beneficial for heat storage under the fluidization.Especially,bagasse-templated pellets show the highest heat storage conversion of 0.61 after 10 cycles.Moreover,Al_(2)O_(3)as a binder for the pellets helps obtain high mechanical strength.The CaO-based pellets doped with 10%(mass)bagasse and 5%(mass)Al_(2)O_(3)reach the highest heat storage density of 1621 kJ·kg^(-1) after 30 cycles and the highest crushing strength of 4.98 N.The microstructure of the bagasse-templated pellets appears more porous than that of biomass-free pellets.The bagassetemplated CaO-based pellets doped with Al_(2)O_(3)seem promising for thermochemical heat storage under the fluidization,owing to the enhanced heat storage capacity,excellent mechanical strength,and simplicity of the synthesis procedure.展开更多
Cracks easily generate in concrete at early age owing to the shrinkage deformation.CaO-based expansion agent(CEA)and superabsorbent polymers(SAP)have been extensively used for the mitigation of concrete shrinkage.The ...Cracks easily generate in concrete at early age owing to the shrinkage deformation.CaO-based expansion agent(CEA)and superabsorbent polymers(SAP)have been extensively used for the mitigation of concrete shrinkage.The macroscopic properties of concrete are highly determined by the microstructure.In this study,the influence of CEA and SAP addition on the pore structure evolution of cement paste under different curing temperatures was evaluated via low-field nuclear magnetic resonance spectroscopy.Test results indicated that,in cement paste,a higher CEA content led to a higher porosity and a larger most probable pore diameter(MPPD).Meanwhile,SAP addition increased the porosity and MPPD of CEA cement paste at early age but decreased them after 7 d,and a higher SAP content always brought a higher porosity and MPPD.Furthermore,the addition of SAP led to a lower porosity and MPPD of CEA cement paste than that of plain cement paste after 14 d.Moreover,the porosity and MPPD of CEA cement paste decreased first and subsequently increased as the curing temperature raised.展开更多
The compound nano-ZnO modified with Ce was prepared by homogeneous precipitation.IR,XRD and dynamic experiments show that the crystal size of nano-ZnO desulfurizer is decreased after being modified with Ce and its des...The compound nano-ZnO modified with Ce was prepared by homogeneous precipitation.IR,XRD and dynamic experiments show that the crystal size of nano-ZnO desulfurizer is decreased after being modified with Ce and its desulfurization activities are improved greatly.When calcined at 270 ℃,Ce distributes evenly on the ZnO particle surface as amorphous state oxides,and the amorphous ZnO·H2O also exists;when the calcining temperature is 570 ℃,the crystal CeO2 separates out and the amorphous structure of zinc oxide disappears,at the same time,the crystal is perfect and its size increases,but the desulfurization activities decrease.The desulfurization product of nano-ZnO modified with Ce was analyzed with XPS.The results show that the adsorption compound of HS,S and ZnS exists on the surface of the desulfurizer.展开更多
Catalytic oxidation desulfurization(CODS)technology has shown great promise for diesel desulfurization by virtue of its low cost,mild reaction conditions,and superior desulfurization performance.Herein,a series of FeM...Catalytic oxidation desulfurization(CODS)technology has shown great promise for diesel desulfurization by virtue of its low cost,mild reaction conditions,and superior desulfurization performance.Herein,a series of FeMoO_(x)/LaTiO_(y)-z samples with diverse Fe/Mo ratios were prepared via a facile citric acid-assisted method.The impact of Fe incorporation on the dispersion and surface elemental states of Mo species,as well as oxygen species content of the synthesized FeMoO_(x)/LaTiO_(y)-z catalysts were systematically characterized using TEM,BET,UV-vis DRS,XPS,XANES,and reaction kinetics,and their CODS performances were examined for 4,6-DMDBT removal.Experimental results demonstrated that Fe/Mo ratio significantly affected the Ti−O bond strength,surface dispersion and electronic structure of Mo O_(2)species on FeMoO_(x)/LaTiO_(y)-z catalysts.FeMoO_(x)/LaTiO_(y)-2 catalyst showed outstanding cycling durability and the best CODS performance with almost 100%removal of 4,6-DMDBT from model oil within 75 min due to its proper MoO3 dispersion,optimal redox property,and the most oxygen vacancy concentration.Nevertheless,further enhancing Fe content led to the increased dispersion of Mo species,while the decrease active Mo species as well as the increase of steric effect for 4,6-DMDBT accessing to the catalytic reactive sites considerably increase the apparent activation energy of FeMoO_(x)/LaTiO_(y)-z(z>2)catalysts during the CODS process,thereby seriously suppressing their CODS performances.Moreover,Radical trapping experiments reveal that the·,generated by the activation of O_(2)at the active sites,catalytic oxidized 4,6-DMDBT to the product of 4,6-DMDBTO_(2),thereby enabling both deep desulfurization and recovery of high-value 4,6-DMDBTO_(2).These findings offer an alternative strategy to achieve ultra deep desulfurization as well as separate and recover high economic value sulfone substances from diesel.展开更多
The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The result...The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The results showed that,the copper grade of the concentrate obtained from seawater flotation decreased to 24.30%,compared to 24.60%in DI water.Concurrently,the recovery of chalcopyrite decreased from 51.39%to 38.67%,while the selectivity index(SI)also had a reduction from 2.006 to 1.798.The incorporation of ethylene diamine tetraacetic acid(EDTA),sodium silicate(SS),and sodium hexametaphosphate(SHMP)yielded an enhancement in the SI value,elevating it from 1.798 to 1.897,2.250 and 2.153,separately.It is particularly noteworthy that an excess of EDTA resulted in a SI value of merely 1.831.The mechanism of action was elucidated through analysis of surface charge measurements,X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FT-IR),extended Derjaguin-Landau Verwey-Overbeek(E-DLVO)theory,and density functional theory(DFT)calculations.展开更多
In petroleum,mercaptan impurities generate malodorous fumes that pose risks to both human health and the environment,and leading to substandard oil quality.Lye desulfurization is a widely employed technique for elimin...In petroleum,mercaptan impurities generate malodorous fumes that pose risks to both human health and the environment,and leading to substandard oil quality.Lye desulfurization is a widely employed technique for eliminating mercaptans from oil.In traditional scrubber towers,lye and oil are poorly mixed,the desulfurization efficiency is low,and the lye consumption is high.To enhance washing efficiency,a droplet micromixer and corresponding fiber coalescence separator were developed.By optimizing the structure and operating parameters,more effective mixing and separation were achieved,and both caustic washing and desulfurization were enhanced.The proposed mixer/separator outperforms the industry standard by reducing the caustic loading by 30%and offers superior economic and engineering performances.The results of this study offer a direction for designing and optimizing a mercaptan removal unit to enhance the scrubbing effectiveness and decrease expenses to achieve more efficient and green production process.展开更多
The development of highly active functionalized ionic liquids(ILs)as both extractants and catalysts for use in achieving deep desulfurization continues to pose challenges.In this study,a highly efficient oxidative des...The development of highly active functionalized ionic liquids(ILs)as both extractants and catalysts for use in achieving deep desulfurization continues to pose challenges.In this study,a highly efficient oxidative desulfurization system was constructed,composed of dual-acidic ionic liquids(DILs)and H_(2)O_(2)-AcOH.The investigation results of four DILs prepared from different metal chlorides([HSO_(3)C_(3)NEt_(3)]Cl-MnCl_(n),MnCl_(n)=AlCl_(3),ZnCl_(2),CuCl_(2),FeCl_(3))in oxidative desulfurization showed that[HSO_(3)C_(3)NEt_(3)]Cl-AlCl_(3)had an outstanding catalytic effect and significantly promoted the oxidation of sulfides.With a 0.2 g[HSO_(3)C_(3)NEt_(3)]Cl-AlCl_(3),the removal rate of dibenzothiophene(DBT)reached 100%in 10 mL model oil under mild conditions at 55℃for 20 min.The key is its ability to induce the dismutation of su-peroxide anions(·O_(2)^(-)),which facilitates the generation of singlet oxygen(1 O_(2)).The efficient oxidation of DBT is accomplished through a predominantly^(1)O_(2)-mediated_(n)on-radical mechanism.[HSO_(3)C_(3)NEt_(3)]Cl-AlCl_(3)serves as a favorable medium for contact to be made between^(1)O_(2)and sulfides,which indicates an efficient catalytic-adsorption synergy.展开更多
With the acceleration of industrialization,the pollution problem of sulfur dioxide(SO_(2))emitted from coal-fired power plants has become increasingly severe.Although wet flue gas desulfurization(FGD)technology can re...With the acceleration of industrialization,the pollution problem of sulfur dioxide(SO_(2))emitted from coal-fired power plants has become increasingly severe.Although wet flue gas desulfurization(FGD)technology can remove about 95%of SO_(2),its high energy consumption and the corrosion risk of downstream equipment caused by residual SO_(2)(500–3000 ppm)still need to be addressed[1].Previous porous materials(such as MOFs)achieve selective adsorption of SO_(2) through open metal sites,M–OH sites or functional organic groups,but the problem of CO_(2) co-adsorption limits their practical application[2].In recent years,hydrogen-bonded organic frameworks(HOFs)have emerged as a research hotspot due to their reversible hydrogen-bonding networks and flexible structures[3],but their stability under extreme conditions and efficient separation performance still need to be improved[4].展开更多
The development of an efficient dual-function catalytic-sorption system,which seamlessly integrates reaction and separation into a single step for extractant-free systems,represents a transformative advancement in oxi...The development of an efficient dual-function catalytic-sorption system,which seamlessly integrates reaction and separation into a single step for extractant-free systems,represents a transformative advancement in oxidative desulfurization(ODS)process.In this work,we introduce a novel dualfunction amphiphilic biochar(Mo/CBC)catalyst,functionalized with MoO_(3-x)featuring abundant oxygen vacancies,for highly effective extractant-free ODS.The polarity of the biochar was precisely tailored by varying the amount of KOH,leading to the creation of amphiphilic carriers.Subsequent ball milling facilitated the successful loading of MoO_(3-x)onto the biochar surface via an impregnation-calcination route leveraging carbon reduction,resulting in the synthesis of amphiphilic Mo/CBC catalysts.The amphiphilic nature of these catalysts ensures their stable dispersion within the oil phase,while also facilitating their interaction with the oxidant H2O2 and the adsorption of sulfur-containing oxidation products.Characterization techniques,including EPR,XPS,and in situ XRD,verified the existence of abundant oxygen vacancies obtained by carbon reduction on the amphiphilic Mo/CBC catalysts,which significantly boosted their activity in an extractant-free ODs system.Remarkably,the amphiphilic Mo/CBC catalyst displayed exceptional catalytic performance,achieving a desulfurization efficiency of 99.6%in just 10 min without extraction solvent.DFT theoretical calculations further revealed that H_(2)O_(2)readily dissociates into two OH radicals on the O_(vac)-MoO_(3),overcoming a low energy barrier.This process was identified as a key contributor to the catalyst's outstanding ODS performance.Furthermore,other biochar sources,such as rice straw,bamboo,rapeseed oil cake,and walnut oil cake,were investigated to produce Mo-based amphiphilic biochar catalysts,which all showed excellent desulfurization performance.This work establishes a versatile and highly efficient dual-function catalytic-sorption system by designing amphiphilic biochar catalysts enriched with oxygen vacancies,paving the way for the development of universally applicable ODS catalysts for industrial applications.展开更多
As a pyrometallurgical process,circulating fluidized bed(CFB) roasting has good potential for application in desulfurization of high-sulfur bauxite.The gas-solid distribution and reaction during CFB roasting of high-s...As a pyrometallurgical process,circulating fluidized bed(CFB) roasting has good potential for application in desulfurization of high-sulfur bauxite.The gas-solid distribution and reaction during CFB roasting of high-sulfur bauxite were simulated using the computational particle fluid dynamics(CPFD) method.The effect of primary air flow velocity on particle velocity,particle volume distribution,furnace temperature distribution and pressure distribution were investigated.Under the condition of the same total flow of natural gas,the impact of the number of inlets on the desulfurization efficiency,atmosphere mass fraction distribution and temperature distribution in the furnace was further investigated.展开更多
基金Project(2024BAB094)supported by the Key Research and Development Program of Hubei Province,ChinaProject(2024040801020296)supported by the Natural Science Foundation of Wuhan City,ChinaProject(52276113)supported by the National Natural Science Foundation of China。
文摘CaO-based heat carriers have shown great prospects for thermochemical energy storage in concentrated solar power systems due to the features such as rich reserves,environmental safety,high energy storage densities and high operation temperatures.However,the density decay because of sintering and poor direct solar absorption of white CaO based heat carriers are the two main obstacles lying on the way to the realistic applications.This work introduced dark Mn-based inert support into calcium heat carriers,attempting to solve the above problems simultaneously.As an inert support,the finely dispersed Ca_(2)MnO_(4) functioned as the metal framework to resist CaCO_(3)/CaO sintering.Consequently,the cyclic stability of CaO-based heat carriers,resulting in the high energy storage densities of~2000 kJ/kg even over 20 cycles.As a dark material,Ca_(2)MnO_(4) successfully darkened CaO-based heat carriers,thereby greatly enhanced the direct solar absorption.In addition,the granulation of CaO-based heat carriers was also studied.The pellets showed satisfactory attrition resistance with only 9.85 wt% mass loss over 3200 cycles.In general,good physicochemical performance of Mn-doped CaO-based heat carrier endows it with great prospects for solar energy storage.
基金Project supported by the National Natural Science Foundation of China(50478026)
文摘Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfurization activity of nanosized Ce-ZnO had improved greatly,compared to nanosized ZnO desulfurizer.Nanosized Ce-ZnO desulfurizer was characterized by XRD,TPD-MS,XPS,and TEM.The research results indicated that doping Ce decreased the particle size of the nanosized ZnO desulfurizer and ZnS was the principal desulfurization product.There were adsorption complexes of HS and S on the surface of desulfurizer as well.Only a small amount of vapor appeared in the tail gas on the condition of meeting the precision of desulfurization.
基金Sponsored by National Key Technology Research and Development Program in 11th Five-Year Plan of China(2007BAF08B01-03)
文摘CaO-Al2O3-SiO2-CaF2-MgO was selected as the slag system for desulfurization in LF process.The reaction between steel and slag during desulfurization has been simulated by using Factsage software to study the influence of component on the sulfur distribution ratio.In order to research the influence of CaO content,aluminum powder content and its granularity on desulfurization,laboratory experiments have been carried out in a 200 kg inductive furnace.Results showed that the optimal composition of deep desulfurizer is wCaO=64% and aluminium powder 10% with a granularity of 30 μm.Industrial trials showed that the main composition range of final slag in LF process is wCaO=53.0%-57.0%,wAl2O3=23.4%-25.1%,wSiO2=8.1%-10.0%,and wCaF2=3.2%-4.7%.The sulfur mass percent in steel is lower than 0.0008% with a desulfurization rate above 89%.According to the result of industrial production,this desulfurizer could meet the production requirement for ultra-low sulfur steel,of which sulfur mass percent is under 0.0015%
基金Item Sponsored by National Natural Science Foundation of China(59774015)
文摘It is found that strong basic oxides including Li2O,Na2O,K2O and BaO,which are used to replace a part of CaO in CaO-based fluxes,can lower the melting point and the viscosity and enhance the dephosphorizing ability. The mechanism was analysed and the addition of Li2O to CaO based fluxes was recommended.
基金Item Sponsored by National High Technology Research and Development Program(863 Program)of China(2007AA03Z548)Natural Science Foundation of Jiangsu Province of China(BK2010355)
文摘B2O3 is selected as fluxing agent of CaO-based ladle refining slag to decrease the melting temperature as well as to improve the speed of slag forming and the refining efficiency. The effects of B2O3 on the melting temperature of two series of refining slags including the low basicity slags （the mass ratio of CaO/SiO2 is 3--4） and the high basicity slags （the mass ratio of CaO/SiO2 is 5--8.75） were investigated. The slag melting temperature was meas- ured using the hemisphere method. The results indicate that the fluxing action of B2O3 is better than that of CaF2 and A1203. For the CaO-based refining slag with low basicity, the melting temperature is decreased effectively when B2O3 is used to substitute for equal mass of CaF2, Al2O3 and SiO2, respectively. For the CaO-based refining slag with high basicity, when CaF2 is substituted by B2 03, the melting temperature can be decreased remarkably. Espe- cially, when the mass ratios of CaO/Al2O3 and CaO/SiO2 are in the range of 1.1--4.0 and 5.25--8. 0, respectively, the slag melting temperature is lower than 1 300 ℃. Therefore, the 132 03-containing refining slags with high ratios of CaO/Al2O3 and CaO/SiO2 have ultra low melting temperature.
基金the support given by the National Key Research and Development Program of China(2018YFC1901203)Natural Science Foundation of Guangdong Province,China(2021A1515010497)+1 种基金Guangzhou Science and Technology Innovation Development Special FundFundamental Research Funds for the Central Universities(2019MS017)。
文摘High-temperature pyrolysis technology can effectively solve the problem of municipal solid waste pollution.However,the pyrolysis gas contains a large amount of CO_(2),which would adversely affect the subsequent utilization.To address this problem,a novel method of co-precipitation modification with Ca,Mg and Zr metals was proposed to improve the CO_(2)capture performance.X-ray diffraction(XRD)patterns and energy dispersive X-ray spectroscopy analysis showed that the two inert supports MgO and CaZrO_(3)were uniformly distributed in the modified calcium-based sorbents.In addition,the XRD results indicated that CaZrO_(3)was produced by the reaction of ZrO_(2)and CaO at high temperatures.The effects of doping ratios,adsorption temperature,calcination temperature,CO_(2)concentration and calcination atmosphere on the adsorption capacity and cycle stability of the modified calcium-based sorbent were studied.The modified calcium-based sorbent achieved the best CO_(2)capture performance when the doping ratio was 10:1:1 with carbonation at 700℃ under 20%CO_(2)/80%N_(2)atmosphere and calcination at 900℃ under100%N_(2)atmosphere.After ten cycles,the average carbonation conversion rate of Ca-10 sorbent was 72%.Finally,the modified calcium-based sorbents successfully reduced the CO_(2)concentration of the pyrolysis gas from 37%to 5%.
基金supported by the Southwest University of Science and Technology(No.22zx7168)the Sichuan Science and Technology Program(No.2020YFG0186)。
文摘Low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance desulfurizers.In this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative humidities.The results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional desulfurizers.Also,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration performance.Sufficient contact with the nascent surface maximizes the formation of slaked lime.The experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative humidity.Compared with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional desulfurizers.This work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.
基金Supported by Capture CO_2 and Storage Technology Jointly Studied by USA and China(2013DFB60140-04)Northwest University Graduate Innovative Talent Training Project(YZZ12036)
文摘CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate(CaAc_2), which was doped with different elements(Mg, Al,Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer(TGA). The sorbents were characterized by N_2 isothermal adsorption measurements, scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO–Al, CaO–Ce and CaO–La were above 96.2%. After 110 cycles, the cyclic stability of CaO–Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.
基金China National Science and Technology Major Project(2016ZX05017)Sinopec Group Corporation 2020 Science and Technology Project“Organic Sulfur Catalytic Hydrolysis Technology Improves Quality Research”(No.120049-1).
文摘In this experiment,an EG/ChCl deep eutectic solvent(DES)was synthesized using choline chloride(ChCl)and ethylene glycol(EG)as the raw materials.The synthesized DES was characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis.The results demonstrate the successful synthesis of DES.A certain amount of FeCl_(3) and CuSO_(4) was added to the DES to promote the absorption of H_(2)S;thus,a Fe(Ⅲ)-Cu(Ⅱ)coupled DES desulfurization system was obtained.The effects of DES raw materials’ratio,FeCl_(3) concentration,water content,CuSO_(4) concentration,and reaction temperature on the desulfurization efficiency and the regeneration conditions were studied.The results show that ChCl/EG DES with a molar ratio of 1:2 has a better desulfurization effect,and the addition of an appropriate amount of water can effectively promote the dissolution of CuSO_(4) and the absorption of H_(2)S.An appropriate increase in reaction temperature and CuSO_(4) concentration would also promote the absorption of H_(2)S.When the concentration of CuSO_(4) in DES desulfurizer was 0.15 mol/L,the gas speed was 20 mL/min,and the sulfur capacity could reach 10.23 g/L.The desulfurizer could be regenerated by passing O_(2),and the desulfurization efficiency did not change much after repeated use of desulfurization-regeneration many times.The desulfurization product was characterized by XRD as rhombohedral sulfur.
文摘Sulfur dioxide is one of the major pollutants resulting from fuel combustion. In this study, CaO and attapulgite were utilized as raw material for synthesizing CaO/attapulgite (CaO/ATP) desulfurizer. The physicochemical characteristics of CaO/ATP desulfurizer were evaluated by various techniques such as XRD, SEM, FT-IR. The performance of samples was studied in dynamic conditions. Major factors affecting on desulfurization such as weight ratio of CaO to total, types of modifiers, roasting time and temperature were investigated. The desulfurization agent synthesized under optimal synthesis conditions with CaO content of 30 wt% and NaOH modifier, and the desulfurization roasting time of 2 hours and roasting temperature of 600°C, exhibit sulfur tolerance of 10.15 wt%. This desulfurizer with excellent absorbency and catalysis of desulfurization, economical and?environment-friendly, could be especially useful in industrial applications.
基金supported by the National Natural Science Foundation of China(51876105)the Fundamental Research Funds of Shandong University(2018JC039)Major Scientific and Technological Innovation Projects of Key Research&Development Program of Shandong Province(2019JZZY020118).
文摘The CaO-based pellets were fabricated using extrusion-spheronization method for calcium looping thermochemical heat storage under the fluidization.The effects of adhesive,biomass-based pore-forming agent,binder and particle size on the heat storage performance and mechanical property of the CaObased pellets were investigated in a bubbling fluidized bed reactor.The addition of 2%(mass)polyvinylpyrrolidone as an adhesive not only helps granulate,but also improves the heat storage capacity of the pellets.All biomass-templated CaO-based pellets display higher heat storage capacity than biomass-free pellets,indicating that the biomass-based pore-forming agent is beneficial for heat storage under the fluidization.Especially,bagasse-templated pellets show the highest heat storage conversion of 0.61 after 10 cycles.Moreover,Al_(2)O_(3)as a binder for the pellets helps obtain high mechanical strength.The CaO-based pellets doped with 10%(mass)bagasse and 5%(mass)Al_(2)O_(3)reach the highest heat storage density of 1621 kJ·kg^(-1) after 30 cycles and the highest crushing strength of 4.98 N.The microstructure of the bagasse-templated pellets appears more porous than that of biomass-free pellets.The bagassetemplated CaO-based pellets doped with Al_(2)O_(3)seem promising for thermochemical heat storage under the fluidization,owing to the enhanced heat storage capacity,excellent mechanical strength,and simplicity of the synthesis procedure.
基金Projects(51878245,U1965105)supported by the National Natural Science Foundation of ChinaProject(2019GSF110006)supported by the Key Research and Development Program of Shandong Province,China+2 种基金Project(2020Z035)supported by the Ningbo 2025 Science and Technology Major Project,ChinaProject(KJ2017B01)supported by the Scientific Research Project of Department of Education of Anhui Province,ChinaProject(2019CEM001)supported by the State Key Laboratory of High Performance Civil Engineering Materials,China。
文摘Cracks easily generate in concrete at early age owing to the shrinkage deformation.CaO-based expansion agent(CEA)and superabsorbent polymers(SAP)have been extensively used for the mitigation of concrete shrinkage.The macroscopic properties of concrete are highly determined by the microstructure.In this study,the influence of CEA and SAP addition on the pore structure evolution of cement paste under different curing temperatures was evaluated via low-field nuclear magnetic resonance spectroscopy.Test results indicated that,in cement paste,a higher CEA content led to a higher porosity and a larger most probable pore diameter(MPPD).Meanwhile,SAP addition increased the porosity and MPPD of CEA cement paste at early age but decreased them after 7 d,and a higher SAP content always brought a higher porosity and MPPD.Furthermore,the addition of SAP led to a lower porosity and MPPD of CEA cement paste than that of plain cement paste after 14 d.Moreover,the porosity and MPPD of CEA cement paste decreased first and subsequently increased as the curing temperature raised.
基金the National Natural Science Foundation of China(Grant No.50478026)the Science Foundation for Young Scientists of Harbin University of Science and Technology(Grant No.2008XQJZ039)
文摘The compound nano-ZnO modified with Ce was prepared by homogeneous precipitation.IR,XRD and dynamic experiments show that the crystal size of nano-ZnO desulfurizer is decreased after being modified with Ce and its desulfurization activities are improved greatly.When calcined at 270 ℃,Ce distributes evenly on the ZnO particle surface as amorphous state oxides,and the amorphous ZnO·H2O also exists;when the calcining temperature is 570 ℃,the crystal CeO2 separates out and the amorphous structure of zinc oxide disappears,at the same time,the crystal is perfect and its size increases,but the desulfurization activities decrease.The desulfurization product of nano-ZnO modified with Ce was analyzed with XPS.The results show that the adsorption compound of HS,S and ZnS exists on the surface of the desulfurizer.
基金supported by the Natural Science Foundation of Guangdong Province(2024A1515010908,2025A1515011103)Opening Project of Hubei Key Laboratory of Plasma Chemistry and Advanced Materials(2024P11)+2 种基金Postdoctoral Fellowship Program of CPSF(GZC20233104)National Natural Science Foundation of China(22202087)Opening Project of Hubei Key Laboratory of Biomass Fibers and Eco-Dyeing&Finishing(STRZ202418)。
文摘Catalytic oxidation desulfurization(CODS)technology has shown great promise for diesel desulfurization by virtue of its low cost,mild reaction conditions,and superior desulfurization performance.Herein,a series of FeMoO_(x)/LaTiO_(y)-z samples with diverse Fe/Mo ratios were prepared via a facile citric acid-assisted method.The impact of Fe incorporation on the dispersion and surface elemental states of Mo species,as well as oxygen species content of the synthesized FeMoO_(x)/LaTiO_(y)-z catalysts were systematically characterized using TEM,BET,UV-vis DRS,XPS,XANES,and reaction kinetics,and their CODS performances were examined for 4,6-DMDBT removal.Experimental results demonstrated that Fe/Mo ratio significantly affected the Ti−O bond strength,surface dispersion and electronic structure of Mo O_(2)species on FeMoO_(x)/LaTiO_(y)-z catalysts.FeMoO_(x)/LaTiO_(y)-2 catalyst showed outstanding cycling durability and the best CODS performance with almost 100%removal of 4,6-DMDBT from model oil within 75 min due to its proper MoO3 dispersion,optimal redox property,and the most oxygen vacancy concentration.Nevertheless,further enhancing Fe content led to the increased dispersion of Mo species,while the decrease active Mo species as well as the increase of steric effect for 4,6-DMDBT accessing to the catalytic reactive sites considerably increase the apparent activation energy of FeMoO_(x)/LaTiO_(y)-z(z>2)catalysts during the CODS process,thereby seriously suppressing their CODS performances.Moreover,Radical trapping experiments reveal that the·,generated by the activation of O_(2)at the active sites,catalytic oxidized 4,6-DMDBT to the product of 4,6-DMDBTO_(2),thereby enabling both deep desulfurization and recovery of high-value 4,6-DMDBTO_(2).These findings offer an alternative strategy to achieve ultra deep desulfurization as well as separate and recover high economic value sulfone substances from diesel.
基金Project(52174239)supported by the National Natural Science Foundation of ChinaProject(2021YFC2902400)supported by the National Key R&D Program of China。
文摘The chemical composition of seawater affects the desulfurization of chalcopyrite in flotation.In this study,desulfurization experiments of chalcopyrite were conducted in both deionized(DI)water and seawater.The results showed that,the copper grade of the concentrate obtained from seawater flotation decreased to 24.30%,compared to 24.60%in DI water.Concurrently,the recovery of chalcopyrite decreased from 51.39%to 38.67%,while the selectivity index(SI)also had a reduction from 2.006 to 1.798.The incorporation of ethylene diamine tetraacetic acid(EDTA),sodium silicate(SS),and sodium hexametaphosphate(SHMP)yielded an enhancement in the SI value,elevating it from 1.798 to 1.897,2.250 and 2.153,separately.It is particularly noteworthy that an excess of EDTA resulted in a SI value of merely 1.831.The mechanism of action was elucidated through analysis of surface charge measurements,X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FT-IR),extended Derjaguin-Landau Verwey-Overbeek(E-DLVO)theory,and density functional theory(DFT)calculations.
基金supported by the National Natural Science Foundation of China(52025103)the Xplorer Prize(XPLORER-2022-1034).
文摘In petroleum,mercaptan impurities generate malodorous fumes that pose risks to both human health and the environment,and leading to substandard oil quality.Lye desulfurization is a widely employed technique for eliminating mercaptans from oil.In traditional scrubber towers,lye and oil are poorly mixed,the desulfurization efficiency is low,and the lye consumption is high.To enhance washing efficiency,a droplet micromixer and corresponding fiber coalescence separator were developed.By optimizing the structure and operating parameters,more effective mixing and separation were achieved,and both caustic washing and desulfurization were enhanced.The proposed mixer/separator outperforms the industry standard by reducing the caustic loading by 30%and offers superior economic and engineering performances.The results of this study offer a direction for designing and optimizing a mercaptan removal unit to enhance the scrubbing effectiveness and decrease expenses to achieve more efficient and green production process.
基金support provided by South Africa National Research Foundation(UID 95983,113648,137947)Foundation for Innovative Research Groups of the Natural Science Foundation of Hebei Province(no.B2021208005).
文摘The development of highly active functionalized ionic liquids(ILs)as both extractants and catalysts for use in achieving deep desulfurization continues to pose challenges.In this study,a highly efficient oxidative desulfurization system was constructed,composed of dual-acidic ionic liquids(DILs)and H_(2)O_(2)-AcOH.The investigation results of four DILs prepared from different metal chlorides([HSO_(3)C_(3)NEt_(3)]Cl-MnCl_(n),MnCl_(n)=AlCl_(3),ZnCl_(2),CuCl_(2),FeCl_(3))in oxidative desulfurization showed that[HSO_(3)C_(3)NEt_(3)]Cl-AlCl_(3)had an outstanding catalytic effect and significantly promoted the oxidation of sulfides.With a 0.2 g[HSO_(3)C_(3)NEt_(3)]Cl-AlCl_(3),the removal rate of dibenzothiophene(DBT)reached 100%in 10 mL model oil under mild conditions at 55℃for 20 min.The key is its ability to induce the dismutation of su-peroxide anions(·O_(2)^(-)),which facilitates the generation of singlet oxygen(1 O_(2)).The efficient oxidation of DBT is accomplished through a predominantly^(1)O_(2)-mediated_(n)on-radical mechanism.[HSO_(3)C_(3)NEt_(3)]Cl-AlCl_(3)serves as a favorable medium for contact to be made between^(1)O_(2)and sulfides,which indicates an efficient catalytic-adsorption synergy.
基金the support of the National Natural Science Foundation of China(Nos.22205207 and 22378369).
文摘With the acceleration of industrialization,the pollution problem of sulfur dioxide(SO_(2))emitted from coal-fired power plants has become increasingly severe.Although wet flue gas desulfurization(FGD)technology can remove about 95%of SO_(2),its high energy consumption and the corrosion risk of downstream equipment caused by residual SO_(2)(500–3000 ppm)still need to be addressed[1].Previous porous materials(such as MOFs)achieve selective adsorption of SO_(2) through open metal sites,M–OH sites or functional organic groups,but the problem of CO_(2) co-adsorption limits their practical application[2].In recent years,hydrogen-bonded organic frameworks(HOFs)have emerged as a research hotspot due to their reversible hydrogen-bonding networks and flexible structures[3],but their stability under extreme conditions and efficient separation performance still need to be improved[4].
基金supported by the National Natural Science Foundation of China(22162008)the Science and Technology Supporting Project of Guizhou Province([2022]208)+1 种基金the Guizhou Province Local Government Overseas Study Programthe open project of Guizhou Provincial Double Carbon and Renewable Energy Technology Innovation Research Institute.
文摘The development of an efficient dual-function catalytic-sorption system,which seamlessly integrates reaction and separation into a single step for extractant-free systems,represents a transformative advancement in oxidative desulfurization(ODS)process.In this work,we introduce a novel dualfunction amphiphilic biochar(Mo/CBC)catalyst,functionalized with MoO_(3-x)featuring abundant oxygen vacancies,for highly effective extractant-free ODS.The polarity of the biochar was precisely tailored by varying the amount of KOH,leading to the creation of amphiphilic carriers.Subsequent ball milling facilitated the successful loading of MoO_(3-x)onto the biochar surface via an impregnation-calcination route leveraging carbon reduction,resulting in the synthesis of amphiphilic Mo/CBC catalysts.The amphiphilic nature of these catalysts ensures their stable dispersion within the oil phase,while also facilitating their interaction with the oxidant H2O2 and the adsorption of sulfur-containing oxidation products.Characterization techniques,including EPR,XPS,and in situ XRD,verified the existence of abundant oxygen vacancies obtained by carbon reduction on the amphiphilic Mo/CBC catalysts,which significantly boosted their activity in an extractant-free ODs system.Remarkably,the amphiphilic Mo/CBC catalyst displayed exceptional catalytic performance,achieving a desulfurization efficiency of 99.6%in just 10 min without extraction solvent.DFT theoretical calculations further revealed that H_(2)O_(2)readily dissociates into two OH radicals on the O_(vac)-MoO_(3),overcoming a low energy barrier.This process was identified as a key contributor to the catalyst's outstanding ODS performance.Furthermore,other biochar sources,such as rice straw,bamboo,rapeseed oil cake,and walnut oil cake,were investigated to produce Mo-based amphiphilic biochar catalysts,which all showed excellent desulfurization performance.This work establishes a versatile and highly efficient dual-function catalytic-sorption system by designing amphiphilic biochar catalysts enriched with oxygen vacancies,paving the way for the development of universally applicable ODS catalysts for industrial applications.
基金supported by the National Key Research and Development Program of China(2022YFC2904400)Guangxi Science and Technology Major Project(Gui Ke AA23023033)。
文摘As a pyrometallurgical process,circulating fluidized bed(CFB) roasting has good potential for application in desulfurization of high-sulfur bauxite.The gas-solid distribution and reaction during CFB roasting of high-sulfur bauxite were simulated using the computational particle fluid dynamics(CPFD) method.The effect of primary air flow velocity on particle velocity,particle volume distribution,furnace temperature distribution and pressure distribution were investigated.Under the condition of the same total flow of natural gas,the impact of the number of inlets on the desulfurization efficiency,atmosphere mass fraction distribution and temperature distribution in the furnace was further investigated.
