Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operati...Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs.展开更多
High electrochemical performance supercapacitors require activated carbon with high specific surface area,suitable pore size distribution and surface properties,and high electrical conductivity as electrode materials,...High electrochemical performance supercapacitors require activated carbon with high specific surface area,suitable pore size distribution and surface properties,and high electrical conductivity as electrode materials,whereas there exists a trade-off relationship between specific surface area and electrical conductivity,which is not well met by a single type of carbon source.To solve this problem,the coal and sargassum are adopted to obtain the coupling product via co-thermal dissolution,followed by carbonization and KOH activation.The effects of mixing mass ratio and activation temperature on the prepared activated carbon(AC)are investigated using single factor experimental method.The experimental results show that AC_(1/3-800)has abundant micropore and mesopore content,good pore structure connectivity,high electrical conductivity and good wettability,and superior electrochemical properties compared with other activated carbons prepared in this experiment.Its total specific surface area is up to 2098.5 m^(2)·g^(-1),the pore volume is up to 1.33 cm^(3)·g^(-1),the content of mespores with diameter of 6-8 nm is significantly increased,and the pore size distribution is wide and uniform.When the current density increases from 0.1 to 10 A·g^(-1),the gravimetric capacitance decreases from 219 to 186 F·g^(-1)with a capacitance retention of 84.9%,the equivalent series resistance is very small,and the rate performance and reversibility of charging and discharging have also been excellent.展开更多
Obtaining large specific surface areas(SSA)for carbon xerogels poses a significant challenge due to the inevitable volume shrinkage of xerogel.Here,the Zn^(2+) coordination-catalyzed in-situ polymerization approach wa...Obtaining large specific surface areas(SSA)for carbon xerogels poses a significant challenge due to the inevitable volume shrinkage of xerogel.Here,the Zn^(2+) coordination-catalyzed in-situ polymerization approach was proposed to fabricate xerogels with a low shrinkage of 13.03% and a short preparation period of 24 h.In resorcinolformaldehyde(RF)polymerization,ZnCl_(2) could accelerate the reaction kinetics through the coordination of the Zn^(2+) and hydroxyl groups.The gel network with adjustable RF particles(46.5 nm-1.89μm)and narrow neck structures was constructed by changing ZnCl_(2) and ethanol contents,which could resist volume shrinkage during atmospheric drying without solvent exchange.The activated carbon xerogels(ACXs)with hierarchical structure were designed by one-step carbonization/activation due to the pore-forming of ZnCl_(2).The obtained ACXs showed a large SSA of 1689 m^(2)/g,multi-dyes adsorption capacity(methylene blue,Congo red,methyl orange,and Sudan Ⅲ were 625.90,359.46,320.69,and 453.92 mg/g,respectively),and reusability of 100%.The maximum monolayer MB adsorption capacity was 630.28 mg/g.This work presents an efficient strategy to design porous nanomaterials with low shrinkage and large SSA,which illustrates promising applications in separation,adsorption,and photoelectric catalysis.展开更多
Herein,the association between the dynamic adsorption capacity of toluene and several important characteristic values on activated carbon(AC)samples was investigated by multidimensional linear regression.Among the cha...Herein,the association between the dynamic adsorption capacity of toluene and several important characteristic values on activated carbon(AC)samples was investigated by multidimensional linear regression.Among the characteristic values,the carbon tetrachloride(CTC)adsorption value has demonstrated relatively stronger correlation with the toluene adsorption capacity on AC sampleswith diverse sources and forms,particularly in exposure to high-concentration toluene.Notably,the relevance of the toluene adsorption capacity to the CTC value could also be extended to a series of other porous adsorbents,which proved the wide applicability of CTC value in characterizing the adsorption behaviors.Based on these results,a mathematical and visual model was then established to predict the toluene adsorption saturation under different conditions(inlet concentration,adsorption time,initial CTC value,etc.)on diverse AC samples,of which the accuracy has later been verified by experimental data.As such,a fast and accurate estimation of the adsorption behaviors over AC samples,and possibly other porous adsorbents,was realized.展开更多
Designing xerogels at the molecular level to overcome volume shrinkage is a promising strategy for carbon xerogels with desirable structure and performance.Here,we design a xerogel with non-shrinkage by introducing Zn...Designing xerogels at the molecular level to overcome volume shrinkage is a promising strategy for carbon xerogels with desirable structure and performance.Here,we design a xerogel with non-shrinkage by introducing ZnCl_(2) into resorcinol-melamine-formaldehyde polymerization.The gel network consisting of micrometer pores and large particles(0.26-1.35μm)is constructed by the coordination of Zn^(2+) with oxygen/nitrogen-containing groups,which is attributed to the structural support of the rigid triazine skeleton with large steric hindrance.Therefore,the reinforced gel network possesses enough strength to withstand capillary forces during atmospheric drying,and special drying and solvent exchange are avoided.The xerogels show non-shrinkage and a short preparation time of 24 h.The resulted activated carbon xerogels with interconnected hierarchically micro-meso-macropores exhibit an optimal specific surface area of 1520 m^(2)/g(through xerogels pyrolysis and the pore-forming of ZnCl_(2)),high adsorption(methylene blue,I-,Cu^(2+),etc.),and repeated adsorption ability.This work provides novel thought for porous nanomaterials with non-shrinkage and desirable structures in adsorption and energy storage.展开更多
In this work,we investigate how activated carbon(AC)derived from olive pomace biomass can be used as an anode material in lithium-ion batteries.The biomass-derived activated carbon has the potential to be highly effic...In this work,we investigate how activated carbon(AC)derived from olive pomace biomass can be used as an anode material in lithium-ion batteries.The biomass-derived activated carbon has the potential to be highly efficient,deliver high performance,sustainable,and cost-effective in LIBs-related production.The activated carbon is prepared by using H3PO4 as a chemical activation agent,and then calcining the obtained product at 500℃ for different controlled atmospheres under(i)air(AC-Atm),(ii)vacuum(AC-Vac),and(iii)argon(ACArg).The different samples were systematically analyzed using scanning electron microscopy(SEM),Highresolution transmission electron microscopy(HRTEM),energy dispersive spectroscopy(EDS),X-ray fluores-cence(XRF),X-ray diffraction(XRD),FT-IR and Raman spectroscopy,and thermogravimetric analysis(TGA)to assess their properties.The electrochemical properties of the carbonaceous materials were studied by galvano-static cycling,cyclic voltammetry(CV),and electrochemical impedance spectroscopy(EIS).The results showed high specific capacity and stable cycling performance,with capacities of 288,184,and 56 mAh g^(-1) at the current density of 25 mA g^(-1) after 70 cycles for AC-Arg,AC-Vac,and AC-Atm respectively.Furthermore,the CE efficiency was nearly 100%from the first cycles.This study opens up interesting prospects and offers promising oppor-tunities for more efficient recovery of unused olive pomace waste,by integrating it into energy storage appli-cations,particularly sustainable lithium-ion batteries.展开更多
This study addresses the challenges posed by dispersive soil in various engineering fields,including hydraulic and agricultural engineering,by exploring the effects of physical adsorption on soil modification.The prim...This study addresses the challenges posed by dispersive soil in various engineering fields,including hydraulic and agricultural engineering,by exploring the effects of physical adsorption on soil modification.The primary objective is to identify an environmentally friendly stabilizer that can alleviate cracking and erosion resulting from soil dispersivity.Activated carbon(AC),known for its porous nature,was examined for its potential to enhance soil strength and erosion resistance.The charge neutralization process was evaluated by monitoring pH and conductivity,in addition to a comprehensive analysis of microscopic and mineral properties.The results show that high sodium levels or low clay contents result in the dispersive nature of soil in water.However,the incorporation of AC can transform such soil into a non-dispersive state.Moreover,both soil strength and erosion resistance exhibited enhancements with increasing AC content and curing duration.The incorporation of AC resulted in a maximum 5.6-fold increase in unconfined compressive strength and a 1.8-fold increase in tensile strength for dispersive soil.Notably,a significant correlation was observed during the curing phase among soil dispersivity,mechanical properties,and pH values.Microscopic analyses revealed that the porous structure of AC facilitated a filling effect and enhanced adsorption capacity,which contributed to improved soil characteristics and reduced dispersivity.The release of hydrogen ions and the formation of aggregates promote water stability.Validation tests conducted on dispersive soil from northern Shaanxi demonstrated the efficacy of physical adsorption using AC as a viable method for modifying dispersive soil in the water conservancy hub.展开更多
Nitrogen-doped activated carbon(N-AC)was successfully prepared by KOH-activation and nitrogen doping using ammonia(NH3)heat treatment.Coconut shell-derived activated carbon(AC)was heat-treated under NH3 gas in the tem...Nitrogen-doped activated carbon(N-AC)was successfully prepared by KOH-activation and nitrogen doping using ammonia(NH3)heat treatment.Coconut shell-derived activated carbon(AC)was heat-treated under NH3 gas in the temperature range of 700℃-900℃.Likewise,the mixture of potassium hydroxide(KOH)and AC was heated at 800℃,followed by heat treatment underNH3 gas at 800℃(hereafter referred to asKOH-N-AC800).Scanning electron microscopy(SEM),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS)and Brunauer-Emmett-Teller(BET)method were utilized to analyze morphology,crystallinity,chemical bonding,chemical composition and surface area.The surface area and porosity of N-AC increased with increasing NH3 heat treatment.Similarly,the nitrogen content in the N-AC increased from 3.23%to 4.84 at%when the NH3 heat treatment was raised from 700℃ to 800℃.However,the nitrogen content of N-AC decreased to 3.40 at% after using NH3 heat treatment at 900℃.The nitrogen content of KOH-N-AC800 is 5.43 at%.KOH-N-AC800 and N-AC800 exhibited improvements of 33.66% and 26.24%,respectively,in CO_(2) adsorption compared with AC.The enhancement of CO_(2) adsorption of KOH-N-AC800 is attributed to the synergic effect of the nitrogen doping,high surface area,and porosity.The results exhibited that nitrogen sites on the surface play a more significant role in CO_(2) adsorption than surface area and porosity.This work proposes the potential synergistic effect of KOH-activation and nitrogen doping for enhancing the CO_(2) adsorption capacity of activated carbon.展开更多
Modified activated carbons(AS)were fabricated through the oxidation effect of ammonium persulfate and applied to the dynamic adsorption of different acrylate gas.The pore structures,surface chemical properties and sur...Modified activated carbons(AS)were fabricated through the oxidation effect of ammonium persulfate and applied to the dynamic adsorption of different acrylate gas.The pore structures,surface chemical properties and surface morphology of AS were respectively characterized by N2 adsorption,Boehm titration,X-ray Photoelectron Spectroscopy(XPS)and scanning electron microscopy(SEM)techniques.After modification,the specific surface area increased from 954 to 1154 m^(2)·g^(-1).The contents of oxygen-containing functional groups on the AS surface increase obviously and have a great effect on the adsorption behavior of acrylate gases.According to the results of dynamic adsorption,the adsorption capacities of acrylates are as the following order:methyl acrylate(461.9 mg·g^(-1))>methyl methacrylate(436.9 mg·g^(-1))>butyl acrylate(381.8 mg·g^(-1)),which is attributed to the size adaptability of AS pores and acrylates.The adsorption behavior of AS for acrylate gases conforms to the Bangham model and the Temkin model.展开更多
Chemical warfare agents(CWAs)are extremely lethal substances used in warfare and terrorism,capable of causing permanent damage even in small doses,despite medical intervention.Therefore,detection,protection,and detoxi...Chemical warfare agents(CWAs)are extremely lethal substances used in warfare and terrorism,capable of causing permanent damage even in small doses,despite medical intervention.Therefore,detection,protection,and detoxification of CWAs are vital for the safety of first responders,military personnel,and civilians,driving significant research in this area.Herein,we designed and synthesized a poly(-diallyldimethylammonium chloride)(PDDA)mediated cupric oxide(CuO)functionalized activated carbon fabric(ACF),termed ACF@PDDA-CuO,as an adsorbent filter material for self-detoxifying chemical protective clothing.PDDA,a positively charged polyelectrolyte,effectively binds in-situ synthesized CuO to the negatively charged ACF surface,serving as a suitable binder.This study demonstrates the synergistic effects of PDDA-CuO functionalization on ACF,where PDDA treatment enhanced mechanical and comfort properties,and CuO crystal growth significantly improved detoxification efficacy against the CWA Nerve Agent Sarin.Comprehensive analyses,including FTIR,BET surface area analysis,SEM,EDS,TEM,STEM,TGA,XPS,and XRD,confirmed the uniform deposition of CuO and PDDA on the ACF surface.The Cu content on ACF@PDDA-CuO samples was measured via iodometric titration.The materials were evaluated for tensile strength,air permeability,water vapor permeability,nerve agent(Sarin)detoxification,and blister agent(Sulfur Mustard)breakthrough time to assess their applicability for protective clothing.The optimized PDDA-CuO on ACF detoxified 82.04%of Sarin within 18 h,compared to 25.22%by ACF alone,and enhanced tensile strength by 23.67%,air permeability by 24.63%,and water vapor permeability by 3.94%,while maintaining protection against Sulfur Mustard for 24 h.These findings indicate that ACF@PDDA-CuO is a promising candidate for CWA protective clothing,offering robust protection with enhanced comfort.展开更多
The ACF adsorbent with high Cu loading was treated with dielectric barrier discharge plasma to mitigate the negative effects of high Cu loading and enhance PH_(3)and H_(2)S adsorption and oxidation.Bruno-Emmett-Taylor...The ACF adsorbent with high Cu loading was treated with dielectric barrier discharge plasma to mitigate the negative effects of high Cu loading and enhance PH_(3)and H_(2)S adsorption and oxidation.Bruno-Emmett-Taylor(BET)result showed that the specific surface area of the adsorbent after air plasma modification was almost three times that before modification.X-ray photoelectron spectroscopy(XPS)findings revealed that the amino group was added to the adsorbent's surface,increasing lattice oxygen and chemisorbed oxygen.The adsorbent's large specific surface area,excellent surface active oxygen,and abundance of basic groups facilitate PH_(3)and H_(2)S adsorption and oxidation.The scanning electron microscopy showed that air plasma modification exposed more active components and uniformly dispersed them on the surface of adsorbent,thereby improving the adsorption performance.Activity evaluation results showed that the adsorbent has the best ability to capture PH_(3)and H_(2)S after being modified by air plasma at 4 kV voltage for 10 min.The adsorbent's breakthrough ability at high space velocity(WHSV:60,000 h^(−1))is 190 mg P/g and 146 mg S/g,respectively,which is 74%and 60%greater than that before modification.This is a great improvement over previous studies.In addition,the possible mechanism of adsorbent deactivation was proposed.展开更多
To explore the denitration mechanism of iron-vanadium/activated carbon(Fe-V/AC)catalysts in ammonia-selective catalytic reduction(NH_(3)-SCR),the physicochemical properties of Fe-V/AC catalysts were characterized.The ...To explore the denitration mechanism of iron-vanadium/activated carbon(Fe-V/AC)catalysts in ammonia-selective catalytic reduction(NH_(3)-SCR),the physicochemical properties of Fe-V/AC catalysts were characterized.The denitration activities of the Fe-V/AC catalysts in the range of 150-300℃ were evaluated.The increase in denitration temperature leads to the highest and fastest recovery rate of NO conversion in the 10Fe-15V/AC catalyst.However,more metal oxides were attached to the catalyst surface as the V loading increased,and the accumulation occurred.The surface-active components are FeO,Fe_(2)O_(3),Fe_(3)O_(4),VO_(2),and V_(2)O_(5).In addition,the increase in the V loading induced a series of modification effects.A large amount of Fe^(3+)was reduced to Fe^(2+),and a large amount of V^(4+)was oxidized to V^(5+).The surface oxygen species(O_(α))were transformed into lattice oxygen(O_(β)).The presence of a large amount of V species deteriorated the pore-structure parameters and destroyed the oxygen-containing functional groups.Increasing the V loading can effectively increase the Lewis acid sites,thereby promoting NH_(3) adsorption and NO reduction and increasing the stretching vibration of weakly adsorbed ammonia species on the catalyst.The NH_(3) adsorption process produces a notable increase in the concentration of monodentate nitrite(NH_(4)^(+)).The NH_(3)-SCR denitration mechanism of the Fe-V/AC catalyst includes reaction gas adsorption,catalytic denitration of metal active components,and gas desorption.展开更多
Chromium is one of the heavy metal pollutants. Heavy metal chromium-contaminated water will seriously endanger human health after use. There are many ways to remove chromium-containing sewage, and the adsorption metho...Chromium is one of the heavy metal pollutants. Heavy metal chromium-contaminated water will seriously endanger human health after use. There are many ways to remove chromium-containing sewage, and the adsorption method is the most effective and convenient method. The adsorption amount of traditional activated carbon is limited, so it needs to be modified to improve the adsorption rate. This experiment determined a reasonable modification method, and the calcination method was selected for the modification. This paper mainly compares the surface morphological characteristics of activated carbon before and after modification. The modified X-ray diffraction peak is increased and the infrared ray absorption peak increased, and the results show that the surface of the modified activated carbon is more rough than that of the modified activated carbon, the functional groups are increased, and the sulfur and nitrogen are doped on the activated carbon. Therefore, the modified activated carbon has a high removal rate and the best performance under acidic conditions.展开更多
Activated carbon after saturated adsorption of EDTA was used as particle electrode in a three-dimensional electrode reactor to treat EDTA-containing wastewater.Electrochemical method was used to regenerate activated c...Activated carbon after saturated adsorption of EDTA was used as particle electrode in a three-dimensional electrode reactor to treat EDTA-containing wastewater.Electrochemical method was used to regenerate activated carbon after many times of electrolysis.Based on the analysis of infrared spectra of activated carbon after adsorption and repeated electrolysis,EDTA was degraded into glycine,and then non-catalytic activated associated complex was formed with N—H bond on the activated carbon.The catalytic ability of the activated carbon vanished and the EDTA degradation efficiency was dropped.Activated carbon could be effectively regenerated by electrochemical method in the three-dimensional reactor.Effects of electric current,conductivity and pH on activated carbon regeneration were investigated,and the optimum conditions were concluded as follows:100-300 mA of current intensity,1.39 mS/cm of electric conductivity,60 min of electrolysis time and pH 6.0-8.0.Under the optimized conditions,the activity of the activated carbon can be recovered and the residual total organic carbon(TOC) was below 10 mg/L(the initial TOC was 200 mg/L) in the three-dimensional electrode reactor.展开更多
Pt/activated carbon (Pt/AC) catalyst combined with base works efficiently for lactic acid production from glycerol under mild conditions. Base type (LiOH, NaOH, KOH, or Ba(OH)2) and base/glycerol molar ratio sig...Pt/activated carbon (Pt/AC) catalyst combined with base works efficiently for lactic acid production from glycerol under mild conditions. Base type (LiOH, NaOH, KOH, or Ba(OH)2) and base/glycerol molar ratio significantly affected the catalytic performance. The corresponding lactic acid selectivity was in the order of LiOH〉NaOH〉KOH〉Ba(OH)2. An increase in LiOH/glycerol molar ratio ele‐vated the glycerol conversion and lactic acid selectivity to some degree, but excess LiOH inhibited the transformation of glycerol to lactic acid. In the presence of Pt/AC catalyst, the maximum selec‐tivity of lactic acid was 69.3% at a glycerol conversion of 100% after 6 h at 90 °C, with a Li‐OH/glycerol molar ratio of 1.5. The Pt/AC catalyst was recycled five times and was found to exhibit slightly decreased glycerol conversion and stable lactic acid selectivity. In addition, the experimental results indicated that reaction intermediate dihydroxyacetone was more favorable as the starting reagent for lactic acid formation than glyceraldehyde. However, the Pt/AC catalyst had adverse effects on the intermediate transformation to lactic acid, because it favored the catalytic oxidation of them to glyceric acid.展开更多
In order to develop the high photocatalytic activity of TiO2 under visible light as that under ultraviolet light and make it easy to be separated from treated liquor, a visible light response and spherical activated c...In order to develop the high photocatalytic activity of TiO2 under visible light as that under ultraviolet light and make it easy to be separated from treated liquor, a visible light response and spherical activated carbon (SAC) supported photocatalyst doped with upconversion luminescence agent Er3+:YAlO3 was prepared by immobilizing Er3+:YAlO3/TiO2, which was obtained by combination of Er3+:YAlO3 and TiO2 using sol-gel method, on the surface of SAC. The crystal phase composition, surface structure and element distribution, and light absorption of the new photocatalysts were examined by X-ray diffraction (XRD), energy dispersive X-ray spectra (EDS) analysis, scanning electron microscopy (SEM) and fluorescence spectra analysis (FSA). The photocatalytic oxidation activity of the photocatalysts was also evaluated by the photodegradation of methyl orange (MO) in aqueous solution under visible light irradiation from a LED lamp (λ400 nm). The results showed that Er3+:YAlO3 could perform as the upconversion luminescence agent which converts the visible light up to ultraviolet light. The Er3+:YAlO3/TiO2 calcinated at 700 °C revealed the highest photocatalytic activity. The apparent reaction rate constant could reach 0.0197 min-1 under visible light irradiation.展开更多
TiO2-coated activated carbon surface (TAs) composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow (AY) was investigated under UV radiation to es...TiO2-coated activated carbon surface (TAs) composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow (AY) was investigated under UV radiation to estimate activity of catalysts and determine the kinetics. And the effects of parameters including the initial concentration of AY, light intensity and TiO2 content in catalysts were examined. The results indicate that TAs has a higher efficiency in decomposition of AY than P25, pure TiO2 particles as well as the mixture of TiO2 powder and active carbon. The photocatalytic degradation rate is found to follow the pseudo-first order kinetics with respect to the AY concentration. The new kinetic model fairly resembles the classic Langmuir-Hinshelwood equation, and the rate constant is proportional to the square root of the light intensity in a wide range. However, its absorption performance depends on the surface areas of catalysts. The model fits quite well with the experimental data and elucidates phenomena about the effects of the TiO2 content in TAs on the degradation rate.展开更多
A continuous stirred-tank reactor (CSTR) process with granular activated carbon (GAC) was developed for fermentation hydrogen production from molasses-containing wastewater by mixed microbial cultures. Operation a...A continuous stirred-tank reactor (CSTR) process with granular activated carbon (GAC) was developed for fermentation hydrogen production from molasses-containing wastewater by mixed microbial cultures. Operation at 35℃, an initial biomass of 17.74 g·L^-1 and hydraulic retention time (HRT) of 6 h, the CSTR reactor presented a continuous hydrogen production ability of 5.9 L·d^-1 and the biogas was free of methane throughout the experiment. Dissolved fermehtation products were predominated by ethanol and acetate acid, with smaller quantities of propionic acid, butyric acid and valeric acid. It was found that GAC could make the immobilized system durable and stable in response to organic load impacting and low pH value. When the organic loading rate (OLR) ranged from 8 kgCOD/(m^3d) to 4 kgCOD/(m^3d), stable ethanol-type fermentation was formed, and the ethanol and acetate concentrations account for 89% of the total liquid products.展开更多
[Objective] This study aimed to improve comprehensive utilization value of glutinous rice straw and to develop new raw material for preparation of activated carbon. [Method] Using potassium hydroxide as activator and ...[Objective] This study aimed to improve comprehensive utilization value of glutinous rice straw and to develop new raw material for preparation of activated carbon. [Method] Using potassium hydroxide as activator and glutinous rice straw as raw material, activated carbon was prepared. [Result] The optimum technological conditions for preparation of activated carbon from glutinous rice straw were as fol- lows: activator concentration of 2 mol/L, activation time of 60 min, activation tem- perature of 600 ℃ and carbonization temperature of 450℃. The adsorption values of methylene blue and iodine by activated carbon prepared from glutinous rico straw were 10.21 ml/0.1 g and 920.74 mg/g respectively under the optimal conditions. The quality of the prepared activated carbon met the grade two of water quality purifica- tion-using activated carbon quality standard. [Conclusion] This study will provide certain references for comprehensive utilization of glutinous rice straw and preparation of high-performance activated carbon.展开更多
Activated carbon fibers (ACFS) with surface area of 1388 m2/g prepared from paper by chemical activation with KOH has been utilized as the adsorbent for the removal of methylene blue from aqueous solution. The exper...Activated carbon fibers (ACFS) with surface area of 1388 m2/g prepared from paper by chemical activation with KOH has been utilized as the adsorbent for the removal of methylene blue from aqueous solution. The experimental data were analyzed by Langmuir and Freundlich models of adsorption. The effects of pH value on the adsorption capacity of ACFS were also investigated. The rates of adsorption were found to conform to the kinetic model of Pseudo-second-order equation with high values of the correlation coefficients (R〉0.998). The Langmuir isotherm was found to fit the experimental data better than the Feundlich isotherm over the whole concentration range. Maximum adsorption capacity of 520 mg/g at equilibrium was achieved. It was found that pH played a major role in the adsorption process, higher pH value favored the adsorption of MB.展开更多
文摘Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs.
基金supported by the Science and Technology Support Plan for Youth Innovation of Colleges and Universities of Shandong Province of China(2023KJ122)State Grid Shandong Electric Power Company Science and Technology Project(520618240009)Doctoral Research Fund of Shandong Jianzhu University(XNBS1838).
文摘High electrochemical performance supercapacitors require activated carbon with high specific surface area,suitable pore size distribution and surface properties,and high electrical conductivity as electrode materials,whereas there exists a trade-off relationship between specific surface area and electrical conductivity,which is not well met by a single type of carbon source.To solve this problem,the coal and sargassum are adopted to obtain the coupling product via co-thermal dissolution,followed by carbonization and KOH activation.The effects of mixing mass ratio and activation temperature on the prepared activated carbon(AC)are investigated using single factor experimental method.The experimental results show that AC_(1/3-800)has abundant micropore and mesopore content,good pore structure connectivity,high electrical conductivity and good wettability,and superior electrochemical properties compared with other activated carbons prepared in this experiment.Its total specific surface area is up to 2098.5 m^(2)·g^(-1),the pore volume is up to 1.33 cm^(3)·g^(-1),the content of mespores with diameter of 6-8 nm is significantly increased,and the pore size distribution is wide and uniform.When the current density increases from 0.1 to 10 A·g^(-1),the gravimetric capacitance decreases from 219 to 186 F·g^(-1)with a capacitance retention of 84.9%,the equivalent series resistance is very small,and the rate performance and reversibility of charging and discharging have also been excellent.
基金supported by the National Key Research and Development Program of China(No.2023YFB3711501)Shanghai Industrial Collaborative Innovation Leading Group Office(No.XTCX-KJ-2023-53)+3 种基金the Fundamental Research Funds for the Central Universities(No.23D110609)the Open Research Fund of Songshan Lake Materials Laboratory(No.2022SLABFN09)the Foundation of State Key Laboratory of Biobased Material and Green Papermaking,Qilu University of Technology,Shandong Academy of Sciences(No.GZKF202231)the Fundamental Research Funds for the Central Universities and Graduate Student Innovation Fund of Donghua University(No.CUSF-DH-D-2022012).
文摘Obtaining large specific surface areas(SSA)for carbon xerogels poses a significant challenge due to the inevitable volume shrinkage of xerogel.Here,the Zn^(2+) coordination-catalyzed in-situ polymerization approach was proposed to fabricate xerogels with a low shrinkage of 13.03% and a short preparation period of 24 h.In resorcinolformaldehyde(RF)polymerization,ZnCl_(2) could accelerate the reaction kinetics through the coordination of the Zn^(2+) and hydroxyl groups.The gel network with adjustable RF particles(46.5 nm-1.89μm)and narrow neck structures was constructed by changing ZnCl_(2) and ethanol contents,which could resist volume shrinkage during atmospheric drying without solvent exchange.The activated carbon xerogels(ACXs)with hierarchical structure were designed by one-step carbonization/activation due to the pore-forming of ZnCl_(2).The obtained ACXs showed a large SSA of 1689 m^(2)/g,multi-dyes adsorption capacity(methylene blue,Congo red,methyl orange,and Sudan Ⅲ were 625.90,359.46,320.69,and 453.92 mg/g,respectively),and reusability of 100%.The maximum monolayer MB adsorption capacity was 630.28 mg/g.This work presents an efficient strategy to design porous nanomaterials with low shrinkage and large SSA,which illustrates promising applications in separation,adsorption,and photoelectric catalysis.
基金supported by the Key Research and Development Projects in Zhejiang Province(Nos.2023C03127,2024C03114,2024C03108)the Natural Science Foundation of China(Nos.22208300,22078294)+2 种基金the Natural Science Foundation of Zhejiang Province(No.LQ23B060007)the Fundamental Research Funds for the Provincial Universities of Zhejiang(No.RF-A2023004)Zhejiang Provincial Postdoctoral Science Foundation(No.ZJ2023145).
文摘Herein,the association between the dynamic adsorption capacity of toluene and several important characteristic values on activated carbon(AC)samples was investigated by multidimensional linear regression.Among the characteristic values,the carbon tetrachloride(CTC)adsorption value has demonstrated relatively stronger correlation with the toluene adsorption capacity on AC sampleswith diverse sources and forms,particularly in exposure to high-concentration toluene.Notably,the relevance of the toluene adsorption capacity to the CTC value could also be extended to a series of other porous adsorbents,which proved the wide applicability of CTC value in characterizing the adsorption behaviors.Based on these results,a mathematical and visual model was then established to predict the toluene adsorption saturation under different conditions(inlet concentration,adsorption time,initial CTC value,etc.)on diverse AC samples,of which the accuracy has later been verified by experimental data.As such,a fast and accurate estimation of the adsorption behaviors over AC samples,and possibly other porous adsorbents,was realized.
基金supported by the National Key Research and Development Program of China(No.2023YFB3711501)the Shanghai Industrial Collaborative Innovation Leading Group Office(No.XTCX-KJ-2023-53)+3 种基金the Fundamental Research Funds for the Central Universities(No.23D110609)the Open Research Fund of Songshan Lake Materials Laboratory(No.2022SLABFN09)the Foundation of State Key Laboratory of Biobased Material and Green Paper-making,Qilu University of Technology,Shandong Academy of Sciences(No.GZKF202231)the Fundamental Research Funds for the Central Universities and Graduate Student Innovation Fund of Donghua University(No.CUSF-DH-d-2022012).
文摘Designing xerogels at the molecular level to overcome volume shrinkage is a promising strategy for carbon xerogels with desirable structure and performance.Here,we design a xerogel with non-shrinkage by introducing ZnCl_(2) into resorcinol-melamine-formaldehyde polymerization.The gel network consisting of micrometer pores and large particles(0.26-1.35μm)is constructed by the coordination of Zn^(2+) with oxygen/nitrogen-containing groups,which is attributed to the structural support of the rigid triazine skeleton with large steric hindrance.Therefore,the reinforced gel network possesses enough strength to withstand capillary forces during atmospheric drying,and special drying and solvent exchange are avoided.The xerogels show non-shrinkage and a short preparation time of 24 h.The resulted activated carbon xerogels with interconnected hierarchically micro-meso-macropores exhibit an optimal specific surface area of 1520 m^(2)/g(through xerogels pyrolysis and the pore-forming of ZnCl_(2)),high adsorption(methylene blue,I-,Cu^(2+),etc.),and repeated adsorption ability.This work provides novel thought for porous nanomaterials with non-shrinkage and desirable structures in adsorption and energy storage.
文摘In this work,we investigate how activated carbon(AC)derived from olive pomace biomass can be used as an anode material in lithium-ion batteries.The biomass-derived activated carbon has the potential to be highly efficient,deliver high performance,sustainable,and cost-effective in LIBs-related production.The activated carbon is prepared by using H3PO4 as a chemical activation agent,and then calcining the obtained product at 500℃ for different controlled atmospheres under(i)air(AC-Atm),(ii)vacuum(AC-Vac),and(iii)argon(ACArg).The different samples were systematically analyzed using scanning electron microscopy(SEM),Highresolution transmission electron microscopy(HRTEM),energy dispersive spectroscopy(EDS),X-ray fluores-cence(XRF),X-ray diffraction(XRD),FT-IR and Raman spectroscopy,and thermogravimetric analysis(TGA)to assess their properties.The electrochemical properties of the carbonaceous materials were studied by galvano-static cycling,cyclic voltammetry(CV),and electrochemical impedance spectroscopy(EIS).The results showed high specific capacity and stable cycling performance,with capacities of 288,184,and 56 mAh g^(-1) at the current density of 25 mA g^(-1) after 70 cycles for AC-Arg,AC-Vac,and AC-Atm respectively.Furthermore,the CE efficiency was nearly 100%from the first cycles.This study opens up interesting prospects and offers promising oppor-tunities for more efficient recovery of unused olive pomace waste,by integrating it into energy storage appli-cations,particularly sustainable lithium-ion batteries.
基金financially supported by the National Postdoctoral Program for Innovative Talents(Grant No.BX20200287)the National Natural Science Foundation of China(Grant Nos.52079116 and 52378322).
文摘This study addresses the challenges posed by dispersive soil in various engineering fields,including hydraulic and agricultural engineering,by exploring the effects of physical adsorption on soil modification.The primary objective is to identify an environmentally friendly stabilizer that can alleviate cracking and erosion resulting from soil dispersivity.Activated carbon(AC),known for its porous nature,was examined for its potential to enhance soil strength and erosion resistance.The charge neutralization process was evaluated by monitoring pH and conductivity,in addition to a comprehensive analysis of microscopic and mineral properties.The results show that high sodium levels or low clay contents result in the dispersive nature of soil in water.However,the incorporation of AC can transform such soil into a non-dispersive state.Moreover,both soil strength and erosion resistance exhibited enhancements with increasing AC content and curing duration.The incorporation of AC resulted in a maximum 5.6-fold increase in unconfined compressive strength and a 1.8-fold increase in tensile strength for dispersive soil.Notably,a significant correlation was observed during the curing phase among soil dispersivity,mechanical properties,and pH values.Microscopic analyses revealed that the porous structure of AC facilitated a filling effect and enhanced adsorption capacity,which contributed to improved soil characteristics and reduced dispersivity.The release of hydrogen ions and the formation of aggregates promote water stability.Validation tests conducted on dispersive soil from northern Shaanxi demonstrated the efficacy of physical adsorption using AC as a viable method for modifying dispersive soil in the water conservancy hub.
基金funded by Burapha University,grant number SDG 4/2568.
文摘Nitrogen-doped activated carbon(N-AC)was successfully prepared by KOH-activation and nitrogen doping using ammonia(NH3)heat treatment.Coconut shell-derived activated carbon(AC)was heat-treated under NH3 gas in the temperature range of 700℃-900℃.Likewise,the mixture of potassium hydroxide(KOH)and AC was heated at 800℃,followed by heat treatment underNH3 gas at 800℃(hereafter referred to asKOH-N-AC800).Scanning electron microscopy(SEM),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS)and Brunauer-Emmett-Teller(BET)method were utilized to analyze morphology,crystallinity,chemical bonding,chemical composition and surface area.The surface area and porosity of N-AC increased with increasing NH3 heat treatment.Similarly,the nitrogen content in the N-AC increased from 3.23%to 4.84 at%when the NH3 heat treatment was raised from 700℃ to 800℃.However,the nitrogen content of N-AC decreased to 3.40 at% after using NH3 heat treatment at 900℃.The nitrogen content of KOH-N-AC800 is 5.43 at%.KOH-N-AC800 and N-AC800 exhibited improvements of 33.66% and 26.24%,respectively,in CO_(2) adsorption compared with AC.The enhancement of CO_(2) adsorption of KOH-N-AC800 is attributed to the synergic effect of the nitrogen doping,high surface area,and porosity.The results exhibited that nitrogen sites on the surface play a more significant role in CO_(2) adsorption than surface area and porosity.This work proposes the potential synergistic effect of KOH-activation and nitrogen doping for enhancing the CO_(2) adsorption capacity of activated carbon.
基金Funded by the National Natural Science Foundation of China(No.51873167)the Self-determined and Innovative Research Funds of WUT(No.2024-CL-B1-02)。
文摘Modified activated carbons(AS)were fabricated through the oxidation effect of ammonium persulfate and applied to the dynamic adsorption of different acrylate gas.The pore structures,surface chemical properties and surface morphology of AS were respectively characterized by N2 adsorption,Boehm titration,X-ray Photoelectron Spectroscopy(XPS)and scanning electron microscopy(SEM)techniques.After modification,the specific surface area increased from 954 to 1154 m^(2)·g^(-1).The contents of oxygen-containing functional groups on the AS surface increase obviously and have a great effect on the adsorption behavior of acrylate gases.According to the results of dynamic adsorption,the adsorption capacities of acrylates are as the following order:methyl acrylate(461.9 mg·g^(-1))>methyl methacrylate(436.9 mg·g^(-1))>butyl acrylate(381.8 mg·g^(-1)),which is attributed to the size adaptability of AS pores and acrylates.The adsorption behavior of AS for acrylate gases conforms to the Bangham model and the Temkin model.
基金Defence Research and Development Establishment(DRDE),DRDO,Gwalior-474002,(India)for his keen interestencouragement.The DRDE accession number for this manuscript is DRDE-IREC-130-28/03/2024.
文摘Chemical warfare agents(CWAs)are extremely lethal substances used in warfare and terrorism,capable of causing permanent damage even in small doses,despite medical intervention.Therefore,detection,protection,and detoxification of CWAs are vital for the safety of first responders,military personnel,and civilians,driving significant research in this area.Herein,we designed and synthesized a poly(-diallyldimethylammonium chloride)(PDDA)mediated cupric oxide(CuO)functionalized activated carbon fabric(ACF),termed ACF@PDDA-CuO,as an adsorbent filter material for self-detoxifying chemical protective clothing.PDDA,a positively charged polyelectrolyte,effectively binds in-situ synthesized CuO to the negatively charged ACF surface,serving as a suitable binder.This study demonstrates the synergistic effects of PDDA-CuO functionalization on ACF,where PDDA treatment enhanced mechanical and comfort properties,and CuO crystal growth significantly improved detoxification efficacy against the CWA Nerve Agent Sarin.Comprehensive analyses,including FTIR,BET surface area analysis,SEM,EDS,TEM,STEM,TGA,XPS,and XRD,confirmed the uniform deposition of CuO and PDDA on the ACF surface.The Cu content on ACF@PDDA-CuO samples was measured via iodometric titration.The materials were evaluated for tensile strength,air permeability,water vapor permeability,nerve agent(Sarin)detoxification,and blister agent(Sulfur Mustard)breakthrough time to assess their applicability for protective clothing.The optimized PDDA-CuO on ACF detoxified 82.04%of Sarin within 18 h,compared to 25.22%by ACF alone,and enhanced tensile strength by 23.67%,air permeability by 24.63%,and water vapor permeability by 3.94%,while maintaining protection against Sulfur Mustard for 24 h.These findings indicate that ACF@PDDA-CuO is a promising candidate for CWA protective clothing,offering robust protection with enhanced comfort.
基金supported by Yunnan Major Scientific and Technological Projects(No.202202AG050005)Yunnan Fundamental Research Projects(No.202101BE070001-001).
文摘The ACF adsorbent with high Cu loading was treated with dielectric barrier discharge plasma to mitigate the negative effects of high Cu loading and enhance PH_(3)and H_(2)S adsorption and oxidation.Bruno-Emmett-Taylor(BET)result showed that the specific surface area of the adsorbent after air plasma modification was almost three times that before modification.X-ray photoelectron spectroscopy(XPS)findings revealed that the amino group was added to the adsorbent's surface,increasing lattice oxygen and chemisorbed oxygen.The adsorbent's large specific surface area,excellent surface active oxygen,and abundance of basic groups facilitate PH_(3)and H_(2)S adsorption and oxidation.The scanning electron microscopy showed that air plasma modification exposed more active components and uniformly dispersed them on the surface of adsorbent,thereby improving the adsorption performance.Activity evaluation results showed that the adsorbent has the best ability to capture PH_(3)and H_(2)S after being modified by air plasma at 4 kV voltage for 10 min.The adsorbent's breakthrough ability at high space velocity(WHSV:60,000 h^(−1))is 190 mg P/g and 146 mg S/g,respectively,which is 74%and 60%greater than that before modification.This is a great improvement over previous studies.In addition,the possible mechanism of adsorbent deactivation was proposed.
基金financially supported by National Natural Science Foundation of China(No.52264043).
文摘To explore the denitration mechanism of iron-vanadium/activated carbon(Fe-V/AC)catalysts in ammonia-selective catalytic reduction(NH_(3)-SCR),the physicochemical properties of Fe-V/AC catalysts were characterized.The denitration activities of the Fe-V/AC catalysts in the range of 150-300℃ were evaluated.The increase in denitration temperature leads to the highest and fastest recovery rate of NO conversion in the 10Fe-15V/AC catalyst.However,more metal oxides were attached to the catalyst surface as the V loading increased,and the accumulation occurred.The surface-active components are FeO,Fe_(2)O_(3),Fe_(3)O_(4),VO_(2),and V_(2)O_(5).In addition,the increase in the V loading induced a series of modification effects.A large amount of Fe^(3+)was reduced to Fe^(2+),and a large amount of V^(4+)was oxidized to V^(5+).The surface oxygen species(O_(α))were transformed into lattice oxygen(O_(β)).The presence of a large amount of V species deteriorated the pore-structure parameters and destroyed the oxygen-containing functional groups.Increasing the V loading can effectively increase the Lewis acid sites,thereby promoting NH_(3) adsorption and NO reduction and increasing the stretching vibration of weakly adsorbed ammonia species on the catalyst.The NH_(3) adsorption process produces a notable increase in the concentration of monodentate nitrite(NH_(4)^(+)).The NH_(3)-SCR denitration mechanism of the Fe-V/AC catalyst includes reaction gas adsorption,catalytic denitration of metal active components,and gas desorption.
文摘Chromium is one of the heavy metal pollutants. Heavy metal chromium-contaminated water will seriously endanger human health after use. There are many ways to remove chromium-containing sewage, and the adsorption method is the most effective and convenient method. The adsorption amount of traditional activated carbon is limited, so it needs to be modified to improve the adsorption rate. This experiment determined a reasonable modification method, and the calcination method was selected for the modification. This paper mainly compares the surface morphological characteristics of activated carbon before and after modification. The modified X-ray diffraction peak is increased and the infrared ray absorption peak increased, and the results show that the surface of the modified activated carbon is more rough than that of the modified activated carbon, the functional groups are increased, and the sulfur and nitrogen are doped on the activated carbon. Therefore, the modified activated carbon has a high removal rate and the best performance under acidic conditions.
基金Project(2011467062) supported by National Scientific Research Project of Welfare(Environmental) Industry,ChinaProject(50925417) supported by China National Funds for Distinguished Young Scientists+1 种基金Project(50830301) supported by the National Natural Science Foundation of ChinaProject(CX2010B121) supported by Hunan Provincial Innovation Foundation For Postgraduate,China
文摘Activated carbon after saturated adsorption of EDTA was used as particle electrode in a three-dimensional electrode reactor to treat EDTA-containing wastewater.Electrochemical method was used to regenerate activated carbon after many times of electrolysis.Based on the analysis of infrared spectra of activated carbon after adsorption and repeated electrolysis,EDTA was degraded into glycine,and then non-catalytic activated associated complex was formed with N—H bond on the activated carbon.The catalytic ability of the activated carbon vanished and the EDTA degradation efficiency was dropped.Activated carbon could be effectively regenerated by electrochemical method in the three-dimensional reactor.Effects of electric current,conductivity and pH on activated carbon regeneration were investigated,and the optimum conditions were concluded as follows:100-300 mA of current intensity,1.39 mS/cm of electric conductivity,60 min of electrolysis time and pH 6.0-8.0.Under the optimized conditions,the activity of the activated carbon can be recovered and the residual total organic carbon(TOC) was below 10 mg/L(the initial TOC was 200 mg/L) in the three-dimensional electrode reactor.
基金supported by the National Natural Science Foundation of China(21176236)~~
文摘Pt/activated carbon (Pt/AC) catalyst combined with base works efficiently for lactic acid production from glycerol under mild conditions. Base type (LiOH, NaOH, KOH, or Ba(OH)2) and base/glycerol molar ratio significantly affected the catalytic performance. The corresponding lactic acid selectivity was in the order of LiOH〉NaOH〉KOH〉Ba(OH)2. An increase in LiOH/glycerol molar ratio ele‐vated the glycerol conversion and lactic acid selectivity to some degree, but excess LiOH inhibited the transformation of glycerol to lactic acid. In the presence of Pt/AC catalyst, the maximum selec‐tivity of lactic acid was 69.3% at a glycerol conversion of 100% after 6 h at 90 °C, with a Li‐OH/glycerol molar ratio of 1.5. The Pt/AC catalyst was recycled five times and was found to exhibit slightly decreased glycerol conversion and stable lactic acid selectivity. In addition, the experimental results indicated that reaction intermediate dihydroxyacetone was more favorable as the starting reagent for lactic acid formation than glyceraldehyde. However, the Pt/AC catalyst had adverse effects on the intermediate transformation to lactic acid, because it favored the catalytic oxidation of them to glyceric acid.
基金Projects (50908096, 50908097) supported by the National Natural Science Foundation of ChinaProject (20100471251) supported by China Postdoctoral Science Foundation
文摘In order to develop the high photocatalytic activity of TiO2 under visible light as that under ultraviolet light and make it easy to be separated from treated liquor, a visible light response and spherical activated carbon (SAC) supported photocatalyst doped with upconversion luminescence agent Er3+:YAlO3 was prepared by immobilizing Er3+:YAlO3/TiO2, which was obtained by combination of Er3+:YAlO3 and TiO2 using sol-gel method, on the surface of SAC. The crystal phase composition, surface structure and element distribution, and light absorption of the new photocatalysts were examined by X-ray diffraction (XRD), energy dispersive X-ray spectra (EDS) analysis, scanning electron microscopy (SEM) and fluorescence spectra analysis (FSA). The photocatalytic oxidation activity of the photocatalysts was also evaluated by the photodegradation of methyl orange (MO) in aqueous solution under visible light irradiation from a LED lamp (λ400 nm). The results showed that Er3+:YAlO3 could perform as the upconversion luminescence agent which converts the visible light up to ultraviolet light. The Er3+:YAlO3/TiO2 calcinated at 700 °C revealed the highest photocatalytic activity. The apparent reaction rate constant could reach 0.0197 min-1 under visible light irradiation.
基金Project(50802034) supported by the National Natural Science Foundation of ChinaProject(11A093) supported by the Key Project Foundation by the Education Department of Hunan Province,China
文摘TiO2-coated activated carbon surface (TAs) composites were prepared by a sol-gel method with supercritical pretreatment. The photocatalytic degradation of acid yellow (AY) was investigated under UV radiation to estimate activity of catalysts and determine the kinetics. And the effects of parameters including the initial concentration of AY, light intensity and TiO2 content in catalysts were examined. The results indicate that TAs has a higher efficiency in decomposition of AY than P25, pure TiO2 particles as well as the mixture of TiO2 powder and active carbon. The photocatalytic degradation rate is found to follow the pseudo-first order kinetics with respect to the AY concentration. The new kinetic model fairly resembles the classic Langmuir-Hinshelwood equation, and the rate constant is proportional to the square root of the light intensity in a wide range. However, its absorption performance depends on the surface areas of catalysts. The model fits quite well with the experimental data and elucidates phenomena about the effects of the TiO2 content in TAs on the degradation rate.
基金supported by the National Hi-Tech R&D Program (863 Program)Ministry of Science&Technology, China (Grant No. 2006AA05Z109)+1 种基金Shanghai Science and Technology Bureau (Grant No.071605122)Educated programme of excellent doctor of Southeast Forestry University (GRAP09)
文摘A continuous stirred-tank reactor (CSTR) process with granular activated carbon (GAC) was developed for fermentation hydrogen production from molasses-containing wastewater by mixed microbial cultures. Operation at 35℃, an initial biomass of 17.74 g·L^-1 and hydraulic retention time (HRT) of 6 h, the CSTR reactor presented a continuous hydrogen production ability of 5.9 L·d^-1 and the biogas was free of methane throughout the experiment. Dissolved fermehtation products were predominated by ethanol and acetate acid, with smaller quantities of propionic acid, butyric acid and valeric acid. It was found that GAC could make the immobilized system durable and stable in response to organic load impacting and low pH value. When the organic loading rate (OLR) ranged from 8 kgCOD/(m^3d) to 4 kgCOD/(m^3d), stable ethanol-type fermentation was formed, and the ethanol and acetate concentrations account for 89% of the total liquid products.
基金Supported by Guizhou Provincial College Students’ Innovative Entrepreneurial Training Program in 2014(201414440004)~~
文摘[Objective] This study aimed to improve comprehensive utilization value of glutinous rice straw and to develop new raw material for preparation of activated carbon. [Method] Using potassium hydroxide as activator and glutinous rice straw as raw material, activated carbon was prepared. [Result] The optimum technological conditions for preparation of activated carbon from glutinous rice straw were as fol- lows: activator concentration of 2 mol/L, activation time of 60 min, activation tem- perature of 600 ℃ and carbonization temperature of 450℃. The adsorption values of methylene blue and iodine by activated carbon prepared from glutinous rico straw were 10.21 ml/0.1 g and 920.74 mg/g respectively under the optimal conditions. The quality of the prepared activated carbon met the grade two of water quality purifica- tion-using activated carbon quality standard. [Conclusion] This study will provide certain references for comprehensive utilization of glutinous rice straw and preparation of high-performance activated carbon.
基金This work was supported by the National Natural Science Foundation of China (No.50972052) and the Shandong Provincial Natural Science Foundation of China (No.ZR2009FM068 and No.ZR2009FM072).
文摘Activated carbon fibers (ACFS) with surface area of 1388 m2/g prepared from paper by chemical activation with KOH has been utilized as the adsorbent for the removal of methylene blue from aqueous solution. The experimental data were analyzed by Langmuir and Freundlich models of adsorption. The effects of pH value on the adsorption capacity of ACFS were also investigated. The rates of adsorption were found to conform to the kinetic model of Pseudo-second-order equation with high values of the correlation coefficients (R〉0.998). The Langmuir isotherm was found to fit the experimental data better than the Feundlich isotherm over the whole concentration range. Maximum adsorption capacity of 520 mg/g at equilibrium was achieved. It was found that pH played a major role in the adsorption process, higher pH value favored the adsorption of MB.