NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse gas.Therefore,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse effect.Am...NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse gas.Therefore,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse effect.Among the technologies for NF_(3)abatement,the destructive sorption of NF_(3)over metal oxides sorbents is an effective way.Thus,the search for a highly reactive and utilized sorbent for NF_(3)destruction is in great demand.In this work,AlOOH supported on carbon-sphere(AlOOH/CS)as precursors were synthesized hydrothermally and heat-treated to prepare the Al_(2)O_(3)sorbents.The influence of AlOOH/CS hydrothermal temperatures on the reactivity of derived Al_(2)O_(3)sorbents for NF_(3)destruction was investigated,and it is shown that the Al2O3 from AlOOH/CS hydro-thermalized at 120℃is superior to others.Subsequently,the optimized Al_(2)O_(3)was covered by Mn(OH)x to prepare Mn/Al_(2)O_(3)sorbents via changing hydrothermal temperatures and Mn loadings.The results show that the Mn/Al_(2)O_(3)sorbents are more utilized than bare Al_(2)O_(3)in NF_(3)destructive sorption due to the promotional effect of Mn_(2)O_(3)as surface layer on the fluorination of Al_(2)O_(3)as substrate,especially the optimal 5%Mn/Al2O3(160℃)exhibits a utilization percentage as high as 90.4%,and remarkably exceeds all the sorbents reported so far.These findings are beneficial to develop more efficient sorbents for the destruction of NF_(3).展开更多
Steelmaking industry faces urgent demands for both steel slag utilization and CO_(2)abatement.Ca and Mg of steel slag can be extracted by acid solution and used to prepare sorbents for CO_(2)capture.In this work,the c...Steelmaking industry faces urgent demands for both steel slag utilization and CO_(2)abatement.Ca and Mg of steel slag can be extracted by acid solution and used to prepare sorbents for CO_(2)capture.In this work,the calcium-based sorbents were prepared from stainless steel slag leachate by co-precipitation,and the initial CO_(2)chemisorption capacity of the calcium-based sorbent prepared from steel slag with the Ca and Mg molar ratio of 3.64:1 was 0.40 g/g.Moreover,the effect of Ca/Mg molar ratio on the morphology,structure,and CO_(2)chemisorption capacity of the calcium-based sorbents were investigated.The results show that the optimal Ca/Mg molar ratio of sorbent for CO_(2)capture was4.2:1,and the skeleton support effect of MgO in calcium-based sorbents was determined.Meanwhile,the chemisorption kinetics of the sorbents was studied using the Avrami-Erofeev model.There were two processes of CO_(2)chemisorption,and the activation energy of the first stage(reaction control)was found to be lower than that of the second stage(diffusion control).展开更多
Using environment-friendly and low-cost biowaste adsorbents as toxic metal ion removal substrates from aqueous solutions has a great economic advantage. This work evaluated pumpkin and potato peel biowastes for the ad...Using environment-friendly and low-cost biowaste adsorbents as toxic metal ion removal substrates from aqueous solutions has a great economic advantage. This work evaluated pumpkin and potato peel biowastes for the adsorption of cadmium ions. The biowastes were treated with acid or base. Batch experiments were carried out by introducing a known concentration of metal ion solution into the biowaste sorbent at various pH levels. The pH and metal ion concentration was monitored with pH and cadmium ion-selective electrode continuously for two hours, and the final concentration for the metal ion after 24 hours was measured with the cadmium electrode and then confirmed with ICP-OES. L-type isotherms were obtained that fit to Freundlich model. Adsorption isotherms showed chemical adsorption and the kinetics following the second order model. Equilibrium adsorption capacity is higher than 29 mg/g at pH 5.6 when the initial concentration is 220 ppm. Dynamic cadmium adsorption capacity is 17 mg/g from aqueous solution when the feed solution is 220 ppm with pumpkin peel biowaste sorbent. The biowaste materials can be regenerated with acid washing.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
Protein wastes (feathers, goat hair) and cellulosic wastes (corn cob, coconut husks) were collected, washed with detergent solution, thoroughly rinsed and sun dried for 2 days before drying in an oven and then ground,...Protein wastes (feathers, goat hair) and cellulosic wastes (corn cob, coconut husks) were collected, washed with detergent solution, thoroughly rinsed and sun dried for 2 days before drying in an oven and then ground, half of ground material was carbonized at a maximum temperature of 500?C after mixing with H2SO4.The carbonized parts were pulverized;both carbonized and uncarbonized sorbents were sieved into two particle sizes of 325 μm and 625 μm using mechanical sieve.1.5 g protein wastes and cellulosic wastes were each used to mop up spilled crude oil, diesel, kerosene and petrol (separately before combining) by encasing them in a sac like boom of 2cm x 2cm x 1cm dimension so as to determine the efficacy of waste sorbents in cleaning hydrocarbon spills. Results of Tables 1(a)-4(a), 1(b)-4(b) and 5-8 shows that the sorbents mopped, desorbed and retained an average of more than 500%, 350% and 300% of their weight of the hydrocarbon sorbates within average of 90 mins contact time, the volume of sorbates mopped up increased significantly when equal weight of activated and unactivated sorbents were combined, the results of equal combination of activated and unactivated sorbents at each particle size and contact time were compared with that of calculated values, high percentage retention observed were a function of mechanism of absorption/adsorption. Each sorbent have a distinct feature that enhances its mopping ability. Large volumes of the hydrocarbon liquids were recovered by mere pressing, the sorbates were mopped up in the order;crude oil > diesel > kerosene > petrol. Protein sorbents with oleophilic and aqua phobic properties absorbed more of all the hydrocarbon liquids than cellulosic sorbents at any particle size and contact, the later tend to be more abundant and therefore cost effective;it was observed that both carbonized and uncarbonized sorbents are good hydrocarbon mops and therefore good alternative to synthetic polyurethane foam already in use. Combination, particle size, activation of sorbents, contact time, viscosity and chain length of hydrocarbon determined the amount of sorbates absorbed/adsorbed, recovered or retained. The residual leachable oil (kerosene) in the sorbents were below 5% and does not constitute serious environmental menace when left in an open dump to decay being biodegradable waste, but a brighter application is that the waste sorbent can be used in making logs as alternative to fire wood or in making particle board for furniture.展开更多
Under the Paris agreement, China has committed to reducing CO_2 emissions by 60%–65% per unit of GDP by 2030.Since CO_2 emissions from coal-fired power plants currently account for over 30% of the total carbon emissi...Under the Paris agreement, China has committed to reducing CO_2 emissions by 60%–65% per unit of GDP by 2030.Since CO_2 emissions from coal-fired power plants currently account for over 30% of the total carbon emissions in China, it will be necessary to mitigate at least some of these emissions to achieve this goal. Studies by the International Energy Agency(IEA) indicate CCS technology has the potential to contribute 14% of global emission reductions, followed by 40% of higher energy efficiency and 35% of renewable energy, which is considered as the most promising technology to significantly reduce carbon emissions for current coal-fired power plants.Moreover, the announcement of a Chinese national carbon trading market in late 2017 signals an opportunity for the commercial deployment of CO_2 capture technologies.Currently, the only commercially demonstrated technology for post-combustion CO_2 capture technology from power plants is solvent-based absorption. While commercially viable, the costs of deploying this technology are high. This has motivated efforts to develop more affordable alternatives, including advanced solvents, membranes,and sorbent capture systems. Of these approaches, advanced solvents have received the most attention in terms of research and demonstration. In contrast, sorbent capture technology has less attention, despite its potential for much lower energy consumption due to the absence of water in the sorbent. This paper reviews recent progress in the development of sorbent materials modified by amine functionalities with an emphasis on material characterization methods and the effects of operating conditions on performance. The main problems and challenges that need to be overcome to improve the competitiveness of sorbent-based capture technologies are discussed.展开更多
With lignite after vacuum drying as the raw material,a series of Zn-based sorbents were prepared by static impregnation,ultrasonic-assisted impregnation,bubbling-assisted impregnation and high-pressure impregnation.Th...With lignite after vacuum drying as the raw material,a series of Zn-based sorbents were prepared by static impregnation,ultrasonic-assisted impregnation,bubbling-assisted impregnation and high-pressure impregnation.The physical properties and the desulfurization performances of Zn-based sorbents were studied systematically by XRD,BET,AAS characterization techniques and the fixed-bed desulfurization evaluation apparatus.The sorbents obtained by high-pressure impregnation method have a larger specific surface area,pore volume and pore diameter comparing with other methods,which is conducive to the sulfidation reaction of hydrogen sulfide gas in the sorbent.The effects of pressure during the high-pressure impregnation and concentration of Zn(NO3)2 precursor solution on the sorbents properties and desulfurization behavior were investigated.The higher the impregnation pressure and the concentration of impregnation solution are,the greater the amount of the active components are uploaded.However,overhigh impregnation pressure can cause collapse and blocking of the carrier pore.The optimal operating condition of high-pressure impregnation method for preparing the sorbents was the impregnation pressure of 20 atm and the solution concentration of 41%.Under that condition,the sorbent had the best desulfurization ability with a sulfur capacity of 13.94 gS/100 gsorbent and a breakthrough time of 54 h.Its desulfurization precision and efficiency of removing H2S before sorbent breakthrough from the middle temperature gases of 400℃ can reach<5 ppm and>99%,respectively.Sorbents could be regenerated under the condition of 1 vol%O2,20 vol% H2O,0.5 vol% NH3,and N2balance gas.The regenerated sorbent could be used for repeated absorption of H2S with a slight decrease in desulfurization effect.展开更多
A new industrial S Zorb sorbent(Ni/Zn O-P) was prepared by using the spray drying technique. The other two traditional sorbents(Ni/Zn O-M and Ni/Zn O-H) were prepared in exactly the same way except the use of differen...A new industrial S Zorb sorbent(Ni/Zn O-P) was prepared by using the spray drying technique. The other two traditional sorbents(Ni/Zn O-M and Ni/Zn O-H) were prepared in exactly the same way except the use of different silica-alumina binder matrices. The XRD, Rietveld quantitative phase analysis, BET, and laser particle size analysis were employed to characterize their physico-chemical properties. The deactivation mechanism and desulfurization kinetics of sorbent was investigated on a water vapor aging treatment device. It was shown that both the water vapor pressure and reaction temperature significantly could influence the formation rate of inactive Zn2 Si O4, which could decrease the sulfur storage capacity of sorbents. The Zn2 Si O4 content profiles could be fitted into the zero order equation, from which the apparent rate constant k and the activation energy E a were calculated. The matrix P greatly raised the E a of Zn2 Si O4 formation due to the less bridged hydroxyl silanol groups on its surface, which accounted for the high stability of Ni/Zn O-P. The desulfurization performance of the fresh and aged sorbents showed that the overall average sulfur conversion of Ni/Zn O-P(aged) was 92%, which was close to that of fresh sorbents(95%), and was higher than that of Ni/Zn O-M(aged)(86%) and Ni/Zn O-H(aged)(90%). Based on these findings, the application of Ni/Zn O-P can greatly improve the long-term running stability of the industrial unit.展开更多
The objective of this work is to study the influences of silica supports and PEG additive on the sorption performance of molecular basket sorbent(MBS) for CO_2 capture consisting of polyethylenimine and one of the fol...The objective of this work is to study the influences of silica supports and PEG additive on the sorption performance of molecular basket sorbent(MBS) for CO_2 capture consisting of polyethylenimine and one of the following supports: SBA-15(2-D structure), TUD-1(3-D sponge-like structure) and fumed silica HS-5(3-D disordered structure). Effects of the supports regarding pore structures and pore properties, the PEI loading amount as well as the sorption temperature were examined. Furthermore, polyethylene glycol(PEG) was introduced as an additive into the sorbents and its effect was investigated at different PEI loadings and sorption temperatures. The results suggest that the pore properties of MBS(after PEI loading) play a more important role in the CO_2 sorption capacity, rather than those of the supports alone.MBS with 3D pore structure exhibits higher CO_2 sorption capacity and amine efficiency than those with 2D-structured support. Among the sorbents studied, fumed silica(HS-5) based MBS showed the highest CO_2 sorption capacity in the temperature range of 30-95 °C, probably due to its unique interstitial pores formed by the aggregation of polymer-loaded SiO_2 particles. It was found that the temperature dependence is directly related to the PEI surface coverage layers. The more PEI surface coverage layers, the higher diffusion barrier for CO_2 and the stronger temperature dependence of CO_2 capacity. 3D MBS exceeds 2D MBS at the same PEI coverage layers due to lower diffusion barrier. Adding PEG can significantly enhance the CO_2 sorption capacity and improve amine efficiency of all MBS, most likely by alleviating the diffusion barrier within PEI bulk layers through the inter-molecular interaction between PEI and PEG.展开更多
Tunnel wash waters characterize all waters that run off after washing procedures of tunnels are performed.These waters represent a wide spectrum of organic and inorganic pollutants,such as polycyclic aromatic hydrocar...Tunnel wash waters characterize all waters that run off after washing procedures of tunnels are performed.These waters represent a wide spectrum of organic and inorganic pollutants,such as polycyclic aromatic hydrocarbons(PAHs)and toxic metals.Removal of such contaminants from water runoff was investigated using laboratory tests after washing procedure was performed on two road tunnels in eastern Norway(Hanekleiv and Bragernes).Due to diverse character of both,treatment media and treated wash waters, the...展开更多
In this paper, study on the effect of preparation conditions of K2CO3/Al2O3 sorbent was done. Box-Behnken design was applied to study the influence of four parameters involve initial solution concentration, impregnati...In this paper, study on the effect of preparation conditions of K2CO3/Al2O3 sorbent was done. Box-Behnken design was applied to study the influence of four parameters involve initial solution concentration, impregnation time and calcination step temperature and time. A quadratic model was used to correlate the sorbent capture capacity. The model was used to calculate the optimum conditions for preparing sorbent. From the analysis of variance (ANOVA), the most influential factor on each experimental design response was identified. The potassium-based sorbents used in this study were prepared by impregnating K2CO3 on Al2O3 support. The CO2 capture capacity was measured in the presence of H2O in a fixed-bed reactor at CO2 capture temperature of 60°C using breakthrough curves. The optimum sorbent prepared by this method showed CO2 capture capacity of 77.21 mg CO2/g sorbent. It was observed that the experimental values obtained were in good agreement with the values predicted by the model, with relatively small errors between the predicted and the actual values. The results obtained in this study can be used as basic data for study on design and operating condition optimization of CO2 capture process using these sorbents.展开更多
Supported ionic liquid(IL) sorbents for CO_2 capture were prepared by impregnating tetramethylammonium glycinate([N1111][Gly]) into four types of porous materials in this study. The CO_2 adsorption behavior was invest...Supported ionic liquid(IL) sorbents for CO_2 capture were prepared by impregnating tetramethylammonium glycinate([N1111][Gly]) into four types of porous materials in this study. The CO_2 adsorption behavior was investigated in a thermogravimetric analyzer(TGA). Among them, poly(methyl methacrylate)(PMMA)-[N1111][Gly]exhibits the best CO_2 adsorption properties in terms of adsorption capacity and rate. The CO_2 adsorption capacity reaches up to 2.14 mmol·g-1 sorbent at 35 °C. The fast CO_2 adsorption rate of PMMA-[N1111][Gly] allows 60 min of adsorption equilibrium time at 35 °C and much shorter time of 4 min is achieved at 75 °C. Further, Avrami's fractional-order kinetic model was used and fitted well with the experiment data, which shows good consistency between experimental results and theoretical model. In addition, PMMA-[N1111][Gly] remained excellent durability in the continuous adsorption–desorption cycling test. Therefore, this stable PMMA-[N1111][Gly] sorbent has great potential to be used for fast CO_2 adsorption from flue-gas.展开更多
In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have be...In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have been described. This part presents the results of removal of toxic metals. The metals of concern (Al, As, Cd, Cr, Cu, Fe, Pb, Mo, Ni, and Zn) were selected based on the priority toxicant pollutants defined in surface water quality criteria. Concentrations of these metals in the collected effluents varied more than the concentrations of PAHs and NPO, and thus only metal contents were considered for statistical analyses. These analyses determined significant differences (P < 0.05, P < 0.01, and P < 0.001) between the mean metal concentrations in the column effluents and those in applied wash water of road tunnel. The results obtained during both experiments revealed that the organic sorbents, and in particular their combination, removed toxic metals more effectively from wash water of road tunnel than from wash water of tunnel electrostatic filters. Among the investigated toxicants, Al and Fe showed the highest levels of reduction in the column experiment, 99.7% and 99.6%, respectively. The lowest reduction levels of 66.0% and 76.2% were found for Pb and Mo, respectively. The results of the bag experiment showed that even one day treatment of wash waters from tunnel electrostatic filters could reduce concentration of some toxicants by more than 70% (Al and Fe) and 80% (Cu).展开更多
A new series of MR-IPN polyacrylamide—poly(vinyl-ethylenediamine)chelatesorbents were prepared by the reaction of ethylenediamine with MR-IPN matrixes.The newchelate sorbent showed good sorption properties for auric ...A new series of MR-IPN polyacrylamide—poly(vinyl-ethylenediamine)chelatesorbents were prepared by the reaction of ethylenediamine with MR-IPN matrixes.The newchelate sorbent showed good sorption properties for auric and platinic ions.展开更多
Due to the restriction such as the Minamata Convention as well as the IED of the European Commission,mercury removal from flue gases of coal-fired power plants(CPP)is an increasingly important environmental issue.This...Due to the restriction such as the Minamata Convention as well as the IED of the European Commission,mercury removal from flue gases of coal-fired power plants(CPP)is an increasingly important environmental issue.This makes this topic very crucial for both the energy industry and scientists.This paper shows how mercury arises from natural resources,i.e.,coals,through their combustion processes in CPP and considers the issue of mercury content in flue gases and solid-state coal combustion by-products.The main part of this paper presents a review of the solid sorbents available for elemental mercury control and removal processes,tested on a laboratory scale.The described solutions have a potential for wider usage in exhaust gas treatment processes in the energy production sector.These solutions represent the latest developments in the field of elemental mercury removal from gases.The authors present an overview of the wide range of solid sorbents and their modifications intended to increase affinity for Hg^(0).Among the presented sorbents are the wellknown activated carbon solutions but also novel modifications to these and other innovative sorbent proposals based on,e.g.,zeolites,biochars,other carbon-based materials,metal-organic frameworks.The paper presents a wide range of characteristics of the described sorbents,as well as the conditions for the Hg^(0) removal experiments summarizing the compendium of novel solid sorbent solutions dedicated to the removal of elemental mercury from gases.展开更多
A new kind of hydrophobic crude oil sorbent was successfully developed by grafting kenaf shive with styrene monomer. In this paper, crude oil sorbents were developed through regeneration method by varying the initiato...A new kind of hydrophobic crude oil sorbent was successfully developed by grafting kenaf shive with styrene monomer. In this paper, crude oil sorbents were developed through regeneration method by varying the initiator concentration, monomer ratio and particle sizes in the range of 0.5 - 2.5 wt%, 0.5 - 2.0 wt % and 125 - 1000 μm respectively. This research approach for the development of crude oil sorbent from graft modified kenaf shive/core and the aforementioned variable optimization has not been reported. The effect studies of the individual and combine factors were carried out using a statistical experimental design matrix using five-level central composite design (CCD). Respond surface methodology (RSM) was used to optimise and develop equations of the aforementioned variables (initiator concentration, monomer ratio and particle sizes). The optimal swelling capacity of 616% and 267% lower retention were achieved at initiator concentration, monomer ratio and particle size of 12.5 wt%, 1.50 wt% and 562 μm respectively. TGA-DTA, XRD and BET analysis were carried out on optimised sample and, FTIR was carried on both unmodified (UG) and optimized sorbent. Further computations were done for grafting efficiency (GE), homopolymers and density. The findings display the effect of the three variables and navigation equations were generated for further investigations on them. However, the results show the feasibility and robustness of facile oil sorption.展开更多
Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences has developed some novel sorbents designed for the filter units of the passive filtration system for radioactive discharge from the int...Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences has developed some novel sorbents designed for the filter units of the passive filtration system for radioactive discharge from the intercontainment space during heavy accidents with a complete loss of electricity supply at nuclear power plants. These are granulated sorbents based on large-pore silica gel containing nanometric particles of Ag or Ag-Ni compounds (trademark Fizkhimin). The sorbents allow to remove various radioactive iodine species (inorganic ones and methyl iodide) from a steam-gas phase with at least 104 decontamination factor. The high sorption properties of Fizkhimin sorbent with Ag particles were confirmed during tests at a test facility of the TUV Sudwest company (Karlsruhe, Germany). This passive filtration system is installed at the 1st and 2nd units of the Kudankulam nuclear power plant (India) and it is unique in the world practice.展开更多
In this paper,a low-cost and environmental-friendly leaching agent citric acid(C_(6)H_(8)O_(7))was used to treat the sediment of Dianchi Lake(SDL)to synthesize lithium silicate(Li_(4)SiO_(4))based CO_(2)sorbent.The re...In this paper,a low-cost and environmental-friendly leaching agent citric acid(C_(6)H_(8)O_(7))was used to treat the sediment of Dianchi Lake(SDL)to synthesize lithium silicate(Li_(4)SiO_(4))based CO_(2)sorbent.The results were compared with that treated with strong acid.Moreover,the effects of preparation conditions,sorption conditions and desorption conditions on the CO_(2)sorption performance of prepared Li_(4)SiO_(4)were systematically studied.Under optimal conditions,the Li_(4)SiO_(4)sorbent was successfully synthesized and its CO_(2)sorption capacity reached 31.37%(mass),which is much higher than that synthesized from SDL treated with strong acid.It is speculated that the presence of some elements after C_(6)H_(8)O_(7)treatment may promote the sorption of synthetic Li_(4)SiO_(4)to CO_(2).In addition,after doping with K_(2)CO_(3),the CO_(2)uptake increases from the original 12.02%and 22.12%to 23.96%and 32.41%(mass)under the 20%and 50%CO_(2)partial pressure,respectively.More importantly,after doping K_(2)CO_(3),the synthesized Li_(4)SiO_(4)has a high cyclic stability under the low CO_(2)partial pressure.展开更多
CuMn_(2)O_(4)spinel has been regarded as a highly efficient sorbent for Hg^(0)capture from flue gas.The regenerability and recyclability of CuMn_(2)O_(4)sorbent are mainly associated with the mercury speciation adsorb...CuMn_(2)O_(4)spinel has been regarded as a highly efficient sorbent for Hg^(0)capture from flue gas.The regenerability and recyclability of CuMn_(2)O_(4)sorbent are mainly associated with the mercury speciation adsorbed on its surface.However,the effect mechanism of HCl on Hg^(0)transformation over CuMn_(2)O_(4)sorbent is still elusive.Experiments were conducted to understand the effect of HCl on Hg^(0)transformation over CuMn_(2)O_(4)sorbent.The results indicate thatCuMn_(2)O_(4)sorbent is a mesoporousmaterial and possesses a good thermal stability.CuMn_(2)O_(4)shows>95%Hg^(0)removal efficiency in a wide temperature window of 50-350℃.The favorable electron-transfer environment caused by the mixed valence states of Cu and Mn cations is responsible for the excellent Hg^(0)removal performance of CuMn_(2)O_(4)sorbent.CuMn_(2)O_(4)shows a higherHg^(0)adsorption capacity of 4774.57μg/g.Hg^(0)adsorption process over CuMn_(2)O_(4)sorbent can bewell described by the developed kinetic model.Hg^(0)removal efficiency of CuMn_(2)O_(4)sorbent does not depend on the presence of HCl.Mercury species adsorbed on the CuMn_(2)O_(4)sorbent in the presence of HCl mainly exist in the forms of Hg^(O)and HgCl_(2)O_(8)·H_(2)O.HCl shows a significant effect on mercury speciation over CuMn_(2)O_(4)sorbent.Most of Hg^(O)species will be transformed into HgCl_(2)O_(8)·H_(2)O in the presence of HCl.展开更多
基金The financial support from the Natural Science Foundation of Shandong Province (ZR2020KB003)
文摘NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse gas.Therefore,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse effect.Among the technologies for NF_(3)abatement,the destructive sorption of NF_(3)over metal oxides sorbents is an effective way.Thus,the search for a highly reactive and utilized sorbent for NF_(3)destruction is in great demand.In this work,AlOOH supported on carbon-sphere(AlOOH/CS)as precursors were synthesized hydrothermally and heat-treated to prepare the Al_(2)O_(3)sorbents.The influence of AlOOH/CS hydrothermal temperatures on the reactivity of derived Al_(2)O_(3)sorbents for NF_(3)destruction was investigated,and it is shown that the Al2O3 from AlOOH/CS hydro-thermalized at 120℃is superior to others.Subsequently,the optimized Al_(2)O_(3)was covered by Mn(OH)x to prepare Mn/Al_(2)O_(3)sorbents via changing hydrothermal temperatures and Mn loadings.The results show that the Mn/Al_(2)O_(3)sorbents are more utilized than bare Al_(2)O_(3)in NF_(3)destructive sorption due to the promotional effect of Mn_(2)O_(3)as surface layer on the fluorination of Al_(2)O_(3)as substrate,especially the optimal 5%Mn/Al2O3(160℃)exhibits a utilization percentage as high as 90.4%,and remarkably exceeds all the sorbents reported so far.These findings are beneficial to develop more efficient sorbents for the destruction of NF_(3).
基金financially supported by the National Natural Science Foundation of China(No.52074078)the National Key R&D Program of China(No.2021YFC2901200)+4 种基金the Applied Fundamental Research Program of Liaoning Province(No.2023JH2/101600002)the Liaoning Provincial Natural Science Foundation of China(No.2022-YQ-09)the Shenyang Young Middle-Aged Scientific and Technological Innovation Talent Support Program,China(No.RC220491)the Liaoning Province Steel Industry-University-Research Innovation Alliance Cooperation Project of Bensteel Group,China(No.KJBLM202202)the Fundamental Research Funds for the Central Universities,China(Nos.N2201023,N2325009)。
文摘Steelmaking industry faces urgent demands for both steel slag utilization and CO_(2)abatement.Ca and Mg of steel slag can be extracted by acid solution and used to prepare sorbents for CO_(2)capture.In this work,the calcium-based sorbents were prepared from stainless steel slag leachate by co-precipitation,and the initial CO_(2)chemisorption capacity of the calcium-based sorbent prepared from steel slag with the Ca and Mg molar ratio of 3.64:1 was 0.40 g/g.Moreover,the effect of Ca/Mg molar ratio on the morphology,structure,and CO_(2)chemisorption capacity of the calcium-based sorbents were investigated.The results show that the optimal Ca/Mg molar ratio of sorbent for CO_(2)capture was4.2:1,and the skeleton support effect of MgO in calcium-based sorbents was determined.Meanwhile,the chemisorption kinetics of the sorbents was studied using the Avrami-Erofeev model.There were two processes of CO_(2)chemisorption,and the activation energy of the first stage(reaction control)was found to be lower than that of the second stage(diffusion control).
文摘Using environment-friendly and low-cost biowaste adsorbents as toxic metal ion removal substrates from aqueous solutions has a great economic advantage. This work evaluated pumpkin and potato peel biowastes for the adsorption of cadmium ions. The biowastes were treated with acid or base. Batch experiments were carried out by introducing a known concentration of metal ion solution into the biowaste sorbent at various pH levels. The pH and metal ion concentration was monitored with pH and cadmium ion-selective electrode continuously for two hours, and the final concentration for the metal ion after 24 hours was measured with the cadmium electrode and then confirmed with ICP-OES. L-type isotherms were obtained that fit to Freundlich model. Adsorption isotherms showed chemical adsorption and the kinetics following the second order model. Equilibrium adsorption capacity is higher than 29 mg/g at pH 5.6 when the initial concentration is 220 ppm. Dynamic cadmium adsorption capacity is 17 mg/g from aqueous solution when the feed solution is 220 ppm with pumpkin peel biowaste sorbent. The biowaste materials can be regenerated with acid washing.
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%.
文摘Protein wastes (feathers, goat hair) and cellulosic wastes (corn cob, coconut husks) were collected, washed with detergent solution, thoroughly rinsed and sun dried for 2 days before drying in an oven and then ground, half of ground material was carbonized at a maximum temperature of 500?C after mixing with H2SO4.The carbonized parts were pulverized;both carbonized and uncarbonized sorbents were sieved into two particle sizes of 325 μm and 625 μm using mechanical sieve.1.5 g protein wastes and cellulosic wastes were each used to mop up spilled crude oil, diesel, kerosene and petrol (separately before combining) by encasing them in a sac like boom of 2cm x 2cm x 1cm dimension so as to determine the efficacy of waste sorbents in cleaning hydrocarbon spills. Results of Tables 1(a)-4(a), 1(b)-4(b) and 5-8 shows that the sorbents mopped, desorbed and retained an average of more than 500%, 350% and 300% of their weight of the hydrocarbon sorbates within average of 90 mins contact time, the volume of sorbates mopped up increased significantly when equal weight of activated and unactivated sorbents were combined, the results of equal combination of activated and unactivated sorbents at each particle size and contact time were compared with that of calculated values, high percentage retention observed were a function of mechanism of absorption/adsorption. Each sorbent have a distinct feature that enhances its mopping ability. Large volumes of the hydrocarbon liquids were recovered by mere pressing, the sorbates were mopped up in the order;crude oil > diesel > kerosene > petrol. Protein sorbents with oleophilic and aqua phobic properties absorbed more of all the hydrocarbon liquids than cellulosic sorbents at any particle size and contact, the later tend to be more abundant and therefore cost effective;it was observed that both carbonized and uncarbonized sorbents are good hydrocarbon mops and therefore good alternative to synthetic polyurethane foam already in use. Combination, particle size, activation of sorbents, contact time, viscosity and chain length of hydrocarbon determined the amount of sorbates absorbed/adsorbed, recovered or retained. The residual leachable oil (kerosene) in the sorbents were below 5% and does not constitute serious environmental menace when left in an open dump to decay being biodegradable waste, but a brighter application is that the waste sorbent can be used in making logs as alternative to fire wood or in making particle board for furniture.
基金Supported by the National Key Research and Development Program of China(2017YFB0603301)
文摘Under the Paris agreement, China has committed to reducing CO_2 emissions by 60%–65% per unit of GDP by 2030.Since CO_2 emissions from coal-fired power plants currently account for over 30% of the total carbon emissions in China, it will be necessary to mitigate at least some of these emissions to achieve this goal. Studies by the International Energy Agency(IEA) indicate CCS technology has the potential to contribute 14% of global emission reductions, followed by 40% of higher energy efficiency and 35% of renewable energy, which is considered as the most promising technology to significantly reduce carbon emissions for current coal-fired power plants.Moreover, the announcement of a Chinese national carbon trading market in late 2017 signals an opportunity for the commercial deployment of CO_2 capture technologies.Currently, the only commercially demonstrated technology for post-combustion CO_2 capture technology from power plants is solvent-based absorption. While commercially viable, the costs of deploying this technology are high. This has motivated efforts to develop more affordable alternatives, including advanced solvents, membranes,and sorbent capture systems. Of these approaches, advanced solvents have received the most attention in terms of research and demonstration. In contrast, sorbent capture technology has less attention, despite its potential for much lower energy consumption due to the absence of water in the sorbent. This paper reviews recent progress in the development of sorbent materials modified by amine functionalities with an emphasis on material characterization methods and the effects of operating conditions on performance. The main problems and challenges that need to be overcome to improve the competitiveness of sorbent-based capture technologies are discussed.
基金supported by the National Basic Research Program of China(2012CB723105)the National Natural Science Foundation of China(20976117)Shanxi Graduates Excellent Innovation Project of China(tyut-rc201018a)
文摘With lignite after vacuum drying as the raw material,a series of Zn-based sorbents were prepared by static impregnation,ultrasonic-assisted impregnation,bubbling-assisted impregnation and high-pressure impregnation.The physical properties and the desulfurization performances of Zn-based sorbents were studied systematically by XRD,BET,AAS characterization techniques and the fixed-bed desulfurization evaluation apparatus.The sorbents obtained by high-pressure impregnation method have a larger specific surface area,pore volume and pore diameter comparing with other methods,which is conducive to the sulfidation reaction of hydrogen sulfide gas in the sorbent.The effects of pressure during the high-pressure impregnation and concentration of Zn(NO3)2 precursor solution on the sorbents properties and desulfurization behavior were investigated.The higher the impregnation pressure and the concentration of impregnation solution are,the greater the amount of the active components are uploaded.However,overhigh impregnation pressure can cause collapse and blocking of the carrier pore.The optimal operating condition of high-pressure impregnation method for preparing the sorbents was the impregnation pressure of 20 atm and the solution concentration of 41%.Under that condition,the sorbent had the best desulfurization ability with a sulfur capacity of 13.94 gS/100 gsorbent and a breakthrough time of 54 h.Its desulfurization precision and efficiency of removing H2S before sorbent breakthrough from the middle temperature gases of 400℃ can reach<5 ppm and>99%,respectively.Sorbents could be regenerated under the condition of 1 vol%O2,20 vol% H2O,0.5 vol% NH3,and N2balance gas.The regenerated sorbent could be used for repeated absorption of H2S with a slight decrease in desulfurization effect.
基金supported by the Science and Technology Development projects of SINOPEC, China (Nos. 113138, 112008 and 110099)
文摘A new industrial S Zorb sorbent(Ni/Zn O-P) was prepared by using the spray drying technique. The other two traditional sorbents(Ni/Zn O-M and Ni/Zn O-H) were prepared in exactly the same way except the use of different silica-alumina binder matrices. The XRD, Rietveld quantitative phase analysis, BET, and laser particle size analysis were employed to characterize their physico-chemical properties. The deactivation mechanism and desulfurization kinetics of sorbent was investigated on a water vapor aging treatment device. It was shown that both the water vapor pressure and reaction temperature significantly could influence the formation rate of inactive Zn2 Si O4, which could decrease the sulfur storage capacity of sorbents. The Zn2 Si O4 content profiles could be fitted into the zero order equation, from which the apparent rate constant k and the activation energy E a were calculated. The matrix P greatly raised the E a of Zn2 Si O4 formation due to the less bridged hydroxyl silanol groups on its surface, which accounted for the high stability of Ni/Zn O-P. The desulfurization performance of the fresh and aged sorbents showed that the overall average sulfur conversion of Ni/Zn O-P(aged) was 92%, which was close to that of fresh sorbents(95%), and was higher than that of Ni/Zn O-M(aged)(86%) and Ni/Zn O-H(aged)(90%). Based on these findings, the application of Ni/Zn O-P can greatly improve the long-term running stability of the industrial unit.
基金the support of this work at Penn State by the U.S.Department of Energy,National Energy Technology Laboratorythe financial support by the China Scholarship Council,the Natural Science Foundation of China(No.51176034)the Open Fund of Key Laboratory of Coal-Based CO2 Capture and Geological Storage of Jiangsu Province(2016A05)
文摘The objective of this work is to study the influences of silica supports and PEG additive on the sorption performance of molecular basket sorbent(MBS) for CO_2 capture consisting of polyethylenimine and one of the following supports: SBA-15(2-D structure), TUD-1(3-D sponge-like structure) and fumed silica HS-5(3-D disordered structure). Effects of the supports regarding pore structures and pore properties, the PEI loading amount as well as the sorption temperature were examined. Furthermore, polyethylene glycol(PEG) was introduced as an additive into the sorbents and its effect was investigated at different PEI loadings and sorption temperatures. The results suggest that the pore properties of MBS(after PEI loading) play a more important role in the CO_2 sorption capacity, rather than those of the supports alone.MBS with 3D pore structure exhibits higher CO_2 sorption capacity and amine efficiency than those with 2D-structured support. Among the sorbents studied, fumed silica(HS-5) based MBS showed the highest CO_2 sorption capacity in the temperature range of 30-95 °C, probably due to its unique interstitial pores formed by the aggregation of polymer-loaded SiO_2 particles. It was found that the temperature dependence is directly related to the PEI surface coverage layers. The more PEI surface coverage layers, the higher diffusion barrier for CO_2 and the stronger temperature dependence of CO_2 capacity. 3D MBS exceeds 2D MBS at the same PEI coverage layers due to lower diffusion barrier. Adding PEG can significantly enhance the CO_2 sorption capacity and improve amine efficiency of all MBS, most likely by alleviating the diffusion barrier within PEI bulk layers through the inter-molecular interaction between PEI and PEG.
文摘Tunnel wash waters characterize all waters that run off after washing procedures of tunnels are performed.These waters represent a wide spectrum of organic and inorganic pollutants,such as polycyclic aromatic hydrocarbons(PAHs)and toxic metals.Removal of such contaminants from water runoff was investigated using laboratory tests after washing procedure was performed on two road tunnels in eastern Norway(Hanekleiv and Bragernes).Due to diverse character of both,treatment media and treated wash waters, the...
文摘In this paper, study on the effect of preparation conditions of K2CO3/Al2O3 sorbent was done. Box-Behnken design was applied to study the influence of four parameters involve initial solution concentration, impregnation time and calcination step temperature and time. A quadratic model was used to correlate the sorbent capture capacity. The model was used to calculate the optimum conditions for preparing sorbent. From the analysis of variance (ANOVA), the most influential factor on each experimental design response was identified. The potassium-based sorbents used in this study were prepared by impregnating K2CO3 on Al2O3 support. The CO2 capture capacity was measured in the presence of H2O in a fixed-bed reactor at CO2 capture temperature of 60°C using breakthrough curves. The optimum sorbent prepared by this method showed CO2 capture capacity of 77.21 mg CO2/g sorbent. It was observed that the experimental values obtained were in good agreement with the values predicted by the model, with relatively small errors between the predicted and the actual values. The results obtained in this study can be used as basic data for study on design and operating condition optimization of CO2 capture process using these sorbents.
基金Supported by the National Basic Research Program of China(2013CB733503)the National Natural Science Foundation of China(21136001,21136004,21476106,21428601,21776123)the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions(TAPP)and the Jiangsu Natural Science Foundation(BK20130062)
文摘Supported ionic liquid(IL) sorbents for CO_2 capture were prepared by impregnating tetramethylammonium glycinate([N1111][Gly]) into four types of porous materials in this study. The CO_2 adsorption behavior was investigated in a thermogravimetric analyzer(TGA). Among them, poly(methyl methacrylate)(PMMA)-[N1111][Gly]exhibits the best CO_2 adsorption properties in terms of adsorption capacity and rate. The CO_2 adsorption capacity reaches up to 2.14 mmol·g-1 sorbent at 35 °C. The fast CO_2 adsorption rate of PMMA-[N1111][Gly] allows 60 min of adsorption equilibrium time at 35 °C and much shorter time of 4 min is achieved at 75 °C. Further, Avrami's fractional-order kinetic model was used and fitted well with the experiment data, which shows good consistency between experimental results and theoretical model. In addition, PMMA-[N1111][Gly] remained excellent durability in the continuous adsorption–desorption cycling test. Therefore, this stable PMMA-[N1111][Gly] sorbent has great potential to be used for fast CO_2 adsorption from flue-gas.
基金the Norwegian Public Roads Administration (Statens Vegvesen Vegdirektoratet)Bioforsk programme "Urban Runoff" founded for preparation of this article
文摘In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have been described. This part presents the results of removal of toxic metals. The metals of concern (Al, As, Cd, Cr, Cu, Fe, Pb, Mo, Ni, and Zn) were selected based on the priority toxicant pollutants defined in surface water quality criteria. Concentrations of these metals in the collected effluents varied more than the concentrations of PAHs and NPO, and thus only metal contents were considered for statistical analyses. These analyses determined significant differences (P < 0.05, P < 0.01, and P < 0.001) between the mean metal concentrations in the column effluents and those in applied wash water of road tunnel. The results obtained during both experiments revealed that the organic sorbents, and in particular their combination, removed toxic metals more effectively from wash water of road tunnel than from wash water of tunnel electrostatic filters. Among the investigated toxicants, Al and Fe showed the highest levels of reduction in the column experiment, 99.7% and 99.6%, respectively. The lowest reduction levels of 66.0% and 76.2% were found for Pb and Mo, respectively. The results of the bag experiment showed that even one day treatment of wash waters from tunnel electrostatic filters could reduce concentration of some toxicants by more than 70% (Al and Fe) and 80% (Cu).
文摘A new series of MR-IPN polyacrylamide—poly(vinyl-ethylenediamine)chelatesorbents were prepared by the reaction of ethylenediamine with MR-IPN matrixes.The newchelate sorbent showed good sorption properties for auric and platinic ions.
基金This work was supported by the National Centre for Research and Development project LIDER,Contract Number LIDER/384/L-6/14/NCBR/2015.
文摘Due to the restriction such as the Minamata Convention as well as the IED of the European Commission,mercury removal from flue gases of coal-fired power plants(CPP)is an increasingly important environmental issue.This makes this topic very crucial for both the energy industry and scientists.This paper shows how mercury arises from natural resources,i.e.,coals,through their combustion processes in CPP and considers the issue of mercury content in flue gases and solid-state coal combustion by-products.The main part of this paper presents a review of the solid sorbents available for elemental mercury control and removal processes,tested on a laboratory scale.The described solutions have a potential for wider usage in exhaust gas treatment processes in the energy production sector.These solutions represent the latest developments in the field of elemental mercury removal from gases.The authors present an overview of the wide range of solid sorbents and their modifications intended to increase affinity for Hg^(0).Among the presented sorbents are the wellknown activated carbon solutions but also novel modifications to these and other innovative sorbent proposals based on,e.g.,zeolites,biochars,other carbon-based materials,metal-organic frameworks.The paper presents a wide range of characteristics of the described sorbents,as well as the conditions for the Hg^(0) removal experiments summarizing the compendium of novel solid sorbent solutions dedicated to the removal of elemental mercury from gases.
基金This work was supported by the National Agency of Scientific and Technological Promotion(Grant No.PICT 2016-1611)the Santa Fe Province Agency of Science,Technology and Innovation(Grant No.AC 2015-0005)National University of Rosario(Grant No.BIO517).
文摘A new kind of hydrophobic crude oil sorbent was successfully developed by grafting kenaf shive with styrene monomer. In this paper, crude oil sorbents were developed through regeneration method by varying the initiator concentration, monomer ratio and particle sizes in the range of 0.5 - 2.5 wt%, 0.5 - 2.0 wt % and 125 - 1000 μm respectively. This research approach for the development of crude oil sorbent from graft modified kenaf shive/core and the aforementioned variable optimization has not been reported. The effect studies of the individual and combine factors were carried out using a statistical experimental design matrix using five-level central composite design (CCD). Respond surface methodology (RSM) was used to optimise and develop equations of the aforementioned variables (initiator concentration, monomer ratio and particle sizes). The optimal swelling capacity of 616% and 267% lower retention were achieved at initiator concentration, monomer ratio and particle size of 12.5 wt%, 1.50 wt% and 562 μm respectively. TGA-DTA, XRD and BET analysis were carried out on optimised sample and, FTIR was carried on both unmodified (UG) and optimized sorbent. Further computations were done for grafting efficiency (GE), homopolymers and density. The findings display the effect of the three variables and navigation equations were generated for further investigations on them. However, the results show the feasibility and robustness of facile oil sorption.
文摘Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences has developed some novel sorbents designed for the filter units of the passive filtration system for radioactive discharge from the intercontainment space during heavy accidents with a complete loss of electricity supply at nuclear power plants. These are granulated sorbents based on large-pore silica gel containing nanometric particles of Ag or Ag-Ni compounds (trademark Fizkhimin). The sorbents allow to remove various radioactive iodine species (inorganic ones and methyl iodide) from a steam-gas phase with at least 104 decontamination factor. The high sorption properties of Fizkhimin sorbent with Ag particles were confirmed during tests at a test facility of the TUV Sudwest company (Karlsruhe, Germany). This passive filtration system is installed at the 1st and 2nd units of the Kudankulam nuclear power plant (India) and it is unique in the world practice.
基金the financial support from National Natural Science Foundation of China(21868015,51802135)the Applied Basic Research Programs of Yunnan Province(140520210057)+1 种基金Taif University Researchers Supporting Project number(TURSP-2020/163)Taif University,Taif,Saudi Arabia。
文摘In this paper,a low-cost and environmental-friendly leaching agent citric acid(C_(6)H_(8)O_(7))was used to treat the sediment of Dianchi Lake(SDL)to synthesize lithium silicate(Li_(4)SiO_(4))based CO_(2)sorbent.The results were compared with that treated with strong acid.Moreover,the effects of preparation conditions,sorption conditions and desorption conditions on the CO_(2)sorption performance of prepared Li_(4)SiO_(4)were systematically studied.Under optimal conditions,the Li_(4)SiO_(4)sorbent was successfully synthesized and its CO_(2)sorption capacity reached 31.37%(mass),which is much higher than that synthesized from SDL treated with strong acid.It is speculated that the presence of some elements after C_(6)H_(8)O_(7)treatment may promote the sorption of synthetic Li_(4)SiO_(4)to CO_(2).In addition,after doping with K_(2)CO_(3),the CO_(2)uptake increases from the original 12.02%and 22.12%to 23.96%and 32.41%(mass)under the 20%and 50%CO_(2)partial pressure,respectively.More importantly,after doping K_(2)CO_(3),the synthesized Li_(4)SiO_(4)has a high cyclic stability under the low CO_(2)partial pressure.
基金This work was supported by National Key R&D Program of China(2016YFB0600604)National Natural Science Foundation of China(52006083)Fundamental Research Funds for the Central Universities(2019kfyRCPY021).
文摘CuMn_(2)O_(4)spinel has been regarded as a highly efficient sorbent for Hg^(0)capture from flue gas.The regenerability and recyclability of CuMn_(2)O_(4)sorbent are mainly associated with the mercury speciation adsorbed on its surface.However,the effect mechanism of HCl on Hg^(0)transformation over CuMn_(2)O_(4)sorbent is still elusive.Experiments were conducted to understand the effect of HCl on Hg^(0)transformation over CuMn_(2)O_(4)sorbent.The results indicate thatCuMn_(2)O_(4)sorbent is a mesoporousmaterial and possesses a good thermal stability.CuMn_(2)O_(4)shows>95%Hg^(0)removal efficiency in a wide temperature window of 50-350℃.The favorable electron-transfer environment caused by the mixed valence states of Cu and Mn cations is responsible for the excellent Hg^(0)removal performance of CuMn_(2)O_(4)sorbent.CuMn_(2)O_(4)shows a higherHg^(0)adsorption capacity of 4774.57μg/g.Hg^(0)adsorption process over CuMn_(2)O_(4)sorbent can bewell described by the developed kinetic model.Hg^(0)removal efficiency of CuMn_(2)O_(4)sorbent does not depend on the presence of HCl.Mercury species adsorbed on the CuMn_(2)O_(4)sorbent in the presence of HCl mainly exist in the forms of Hg^(O)and HgCl_(2)O_(8)·H_(2)O.HCl shows a significant effect on mercury speciation over CuMn_(2)O_(4)sorbent.Most of Hg^(O)species will be transformed into HgCl_(2)O_(8)·H_(2)O in the presence of HCl.
