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Kinetic Adsorption of Cd onto Nanometer Al_2O_3/Carbon Fibre 被引量:1
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作者 LI Yu WANG Yue +4 位作者 HAN Weit LI Su-wen ZHAO Hui ZHU Chang-yun WANG Heng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第5期522-524,共3页
A new nanometer material, nano-Al2O3 with carbon fibre as the carrier, was employed for the removal of Cd with low concentrations from polluted water. The characterization of the material was carried out by means of S... A new nanometer material, nano-Al2O3 with carbon fibre as the carrier, was employed for the removal of Cd with low concentrations from polluted water. The characterization of the material was carried out by means of SEM and TEM. Batch adsorption and elution experiments were carried out to determine the adsorption properties of Cd on the new adsorbent. The classical Thomas model was applied to estimating the equilibrium coefficients of Cd adsorption and the saturated adsorption ability. The results show that the Thomas model is fit for describing the kinetic adsorption process, and the maximum adsorption capacity of the nanometer Al2O3/carbon is 69.29 mg/g. The resulting information also indicates that the desorption of Cd eluted with de-ionized water at a rate of 9.8 mL/min can be neglected. With the advantage of a high adsorption capacity for removing low concentration Cd, the Al2O3/carbon fibre possesses the potentiality to be an effective adsorbent for the removal of Cd from polluted water. 展开更多
关键词 Nanometer Al2O3/carbon kinetic adsorption CD Polluted water treatment
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Optimization of Methylene Blue Dye Adsorption onto Coconut Husk Cellulose Using Response Surface Methodology: Adsorption Kinetics, Isotherms and Reusability Studies
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作者 Frank Ouru Omwoyo Geoffrey Otieno 《Journal of Materials Science and Chemical Engineering》 2024年第2期1-18,共18页
In this study, coconut husk cellulose was employed as a cost-effective and environmentally friendly adsorbent to eliminate methylene blue (MB) dye from aqueous solutions. The successful development of response surface... In this study, coconut husk cellulose was employed as a cost-effective and environmentally friendly adsorbent to eliminate methylene blue (MB) dye from aqueous solutions. The successful development of response surface methodology paired with a central composite design (RSM-CCD) enabled the optimization and modelling of the adsorption process. The study investigated the individual and combined effects of three variables (pH, contact time, and initial MB dye concentration) on the adsorption of MB dye onto coconut husk cellulose. The developed RSM-CCD model exhibited a remarkable degree of precision in predicting the removal efficiency of MB dye within the specified experimental parameters. This was demonstrated by the strong regression parameters, with an R<sup>2</sup> value of 99.79% and an adjusted R<sup>2</sup> value of 99.6%. The study depicted that the optimal parameters for attaining a 98.8827% removal of MB dye using coconut husk cellulose were as follows: an initial MB dye concentration of 30 mg∙L<sup>−1</sup>, contact time of 120 minutes, and pH 7 at a fixed adsorbent dose of 0.5 g. The Freundlich isotherm model provided the most satisfactory description of the equilibrium adsorption isotherms, suggesting that MB dye adsorption onto coconut husk cellulose occurs on a heterogeneous surface. The experimental results demonstrated a strong agreement with the pseudo-second-order kinetics model, indicating that the number of active sites present on the cellulose adsorbent predominantly influences the adsorption process of MB dye. Additionally, the adsorbent made from coconut husk cellulose exhibited the potential to be reused, as it retained its efficiency for a maximum of three cycles of adsorption of MB dye. The results of this study show that coconut husk cellulose has the potential to be an effective and sustainable adsorbent for removing MB dye from aqueous solutions. 展开更多
关键词 adsorption kinetics Isotherms OPTIMIZATION Response Surface Methodology CELLULOSE
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Thermodynamics and kinetics of adsorption for heavy metal ions from aqueous solutions onto surface amino-bacterial cellulose 被引量:8
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作者 鲁敏 张月明 +2 位作者 关晓辉 徐小慧 高婷婷 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1912-1917,共6页
Amino-bacterial cellulose(amino-BC) was prepared by chemical modification of bacterial cellulose(BC).The adsorption characteristics and mechanism of amino-BC were studied.The results show that adsorption data can ... Amino-bacterial cellulose(amino-BC) was prepared by chemical modification of bacterial cellulose(BC).The adsorption characteristics and mechanism of amino-BC were studied.The results show that adsorption data can be fitted well by Langmuir equation and the pseudo-second order kinetics,indicating that the adsorption of amino-BC would obey monolayer molecule adsorption and the main action was chemisorption.Meanwhile,the adsorption process was studied by the Elovich equation and the intra-particle diffusion model,indicating that the absorption characteristics of metal ions on amino-BC is controlled by both film diffusion and particle diffusion.The increase of reaction temperature will accelerate the adsorbing rate because of endothermic reaction. 展开更多
关键词 surface amination bacterial cellulose adsorption thermodynamics adsorption kinetics
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Kinetic Adsorption of Ammonium Nitrogen by Substrate Materials for Constructed Wetlands 被引量:22
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作者 ZHU Wen-Ling CUI Li-Hua +2 位作者 OUYANG Ying LONG Cui-Fen TANG Xiao-Dan 《Pedosphere》 SCIE CAS CSCD 2011年第4期454-463,共10页
Constructed wetlands (CWs) are engineered systems that utilize natural systems including wetland vegetations, soils, and their associated microbial assemblages to assist in treating wastewater. The kinetic adsorptio... Constructed wetlands (CWs) are engineered systems that utilize natural systems including wetland vegetations, soils, and their associated microbial assemblages to assist in treating wastewater. The kinetic adsorption of ammonium nitrogen (NH+-N) by CW substrate materials such as blast furnace slag (BFS), zeolite, ceramsite, vermiculite, gravel, paddy soil, red soil, and turf, was investigated using batch experiments and kinetic adsorption isotherms. Both Freundlich and Lang- muir isotherms could adequately predict the NH+-N adsorption process. The maximum adsorption capacities of NH+-N, estimated from the Langmuir isotherm, ranked as: zeolite (33 333.33 mg kg^-1) 〉 turf (29274.01 mg kg^-1) 〉 BFS (5000 mg kg^-1) 〉 vermiculite (3333.33 mg kg^-1) 〉 gravel (769.23 mg kg^-1) 〉 paddy soil (588.24 mg kg^-1) 〉 red soil (555.56 mg kg^-1) 〉 ceramsite (107.53 mg kg^-1). Some properties of the substrate materials, including bulk density, specific gravity, hydraulic conductivity, uniformity coefficient (K60), curvature coefficient (Co), organic matter, pH, exchangeable (or active) Cu, Fe, Zn and Mn, total Cu, and Fe, Mn, Zn, Cd, Pb and Ca, had negative correlations with NH+-N adsorption. Other properties of the substrate materials like particle diameter values of D10, 030 and 060 (the diameters of particle sizes of a substrate material at which 10%, 30% and 60%, respectively, of the particles pass through the sieve based on the accumulative frequency), cation exchange capacity (CEC), exchangeable (or active) Ca and Mg, and total K and Mg had positive correlations with NH+-N adsorption. In addition, active K and Na as well as the total Na had significant positive correlations with NH+-N adsorption. This information would be useful for selection of suitable substrate materials for CWs. 展开更多
关键词 ammonia removal kinetic adsorption capacity Langmuir isotherm physicochemical properties substrate materials
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Equilibrium, thermodynamic, and kinetic of Cr(VI) adsorption using a modified and unmodified bentonite clay 被引量:6
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作者 D.J.L. Guerra I. Mello +2 位作者 L.R. Freitas R. Resende R.A.R. Silva 《International Journal of Mining Science and Technology》 SCIE EI 2014年第4期525-535,共11页
The capacities of natural and modified Brazilian bentonite samples as adsorbents to remove hexavalent metal chromium were investigated under several conditions in batch and column methods. The raw material, Ca-bentoni... The capacities of natural and modified Brazilian bentonite samples as adsorbents to remove hexavalent metal chromium were investigated under several conditions in batch and column methods. The raw material, Ca-bentonite, was modified by anchorament of 3-aminopropyltrietoxisilane (APS) and 3,2- aminoethylaminopropyltrimetoxisilane (AEAPS) in the surface of bentonite sample: This type of new occurrence of bentonite is suitable as a raw material for adsorption process. Adsorption behavior of three bentonite types was strongly depending on pH of adsorbate solution, contact time adsorbent/adsorbate, and initial concentration of Cr(VI). The results were confirmed by column method and reveals that the adsorption process of materials accorded by the Redlich-Peterson, Sips, Dubinin-Radushkevich, and tang- muir isotherm models. The exothermic entbalpic values reflected a favorable energetic process for chro- mium ions anchored in the material surfaces. The negative Gibbs free energy results supported the spontaneity of three adsorption reactions with Cr(VI) ions. 展开更多
关键词 Bentonite Organo-bentonite Chromium Equilibrium kinetic adsorption
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Adsorption of Methylene Blue on magnesium silicate: Kinetics, equilibria and comparison with other adsorbents 被引量:15
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作者 Franco Ferrero 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第3期467-473,共7页
Batch adsorption from aqueous solutions in a slightly basic medium of Methylene Blue, up to 2500 mg/L, onto synthetic magnesium silicate (Florisil) of three particle size ranges (mean diameters of 112, 200 and 425 ... Batch adsorption from aqueous solutions in a slightly basic medium of Methylene Blue, up to 2500 mg/L, onto synthetic magnesium silicate (Florisil) of three particle size ranges (mean diameters of 112, 200 and 425 μm) was compared to the corresponding adsorption onto activated carbon and Amberlite XAD-2. The best fit of the kinetic results was achieved by a pseudo second-order equation. The equilibrium data were found to be well represented by the Langmuir isotherm equation. Amberlite XAD-2, an unspecific adsorbent capable of adsorbing exclusively through a surface effect, exhibited a poor dye uptake, confirming that the adsorption mechanism on Florisil was due to electrostatic attraction and ion exchange. Moreover, the comparison between Florisil and the other adsorbents was performed on the basis of the evaluation of the surface area and pore volume occupied by the adsorbed dye. 展开更多
关键词 dye adsorption magnesium silicate Florisil adsorption kinetics adsorption isotherms
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Adsorption Kinetics of β-Carotene and Chlorophyll onto Acid-activated Bentonite in Model Oil 被引量:9
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作者 童军茂 武占省 +2 位作者 孙喜房 徐小琳 李春 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第2期270-276,共7页
The textural properties of acid-activated bentonite (AAB), which were prepared using four different concentrations of sulfuric acid, were analyzed by adsorption-desorption isotherm of nitrogen using an automated spe... The textural properties of acid-activated bentonite (AAB), which were prepared using four different concentrations of sulfuric acid, were analyzed by adsorption-desorption isotherm of nitrogen using an automated specific surface area and porosity analyzer. The total pore volume, specific surface area and average pore diameter of these four kinds of AAB show a regular changing trend, increasing first and then decreasing, the optimum of which can be achieved at a sulfuric acid concentration of 25% (sample A25). The kinetic analysis of the adsorption of β-carotene and chlorophyll in model oil solutions, namely, xylene and edible oil solution, has been investigated by using AAB. Experimental results indicated that the adsorption data fit the pseudo-second-order model well. The whole adsorption process of the two pigments on AAB was divided basically into two parts: the initial adsorption of pigments was rapid in the first l0 rain, followed by a slower adsorption process till equilibrium was attained at 60 rain. In addition, the amount and rate of adsorption on A25 increase synchronously with the initial pigment concentration and temperature. The results showed that the adsorption kinetics behavior of AAB with respect to the pigments is not influence by the xylene and edible oil solution. 展开更多
关键词 acid-activated bentonite pigment model oil solution adsorption kinetics
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An Adsorption Kinetic Model for Sulfur Dioxide Adsorption by ZL50 Activated Carbon 被引量:8
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作者 高继贤 王铁峰 +4 位作者 舒庆 山尼 温倩 王德峥 王金福 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期223-230,共8页
A semi-empirical adsorption kinetic model was proposed with the time compensation method to describe the chemisorption of SO2 in flue gas by carbon adsorbents for flue gas purification.The change in adsorption capacit... A semi-empirical adsorption kinetic model was proposed with the time compensation method to describe the chemisorption of SO2 in flue gas by carbon adsorbents for flue gas purification.The change in adsorption capacity and adsorption rate with time at different water vapor concentrations and different SO2 concentrations was studied.The model was in good agreement with experimental data.The surface reaction was probably the rate controlling step in the early stage for SO2 adsorption by ZL50 activated carbon.The parameters m and n in the nth order adsorption kinetic model were related to the magnitude of the time compensation and adsorption driving force,respectively.The change of parameter n with water vapor concentrations and sulfur dioxide concentrations was studied and some physical implications were given.The sum of square errors was less than 1.0 and the average absolute percentage deviations ranged from 0.5 to 3.2.The kinetic model was compared with other models in the literature. 展开更多
关键词 adsorption kinetic model time compensation method flue gas purification ZL50 activated carbon adsorption capacity adsorption rate
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Adsorption Kinetics of Pb^(2+) and Cu^(2+) on Variable Charge Soils and Minerals: Ⅱ. Equations for Describing Experimental Data 被引量:3
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作者 HU GUO-SONGInstitute of Soil Science, A cademia Sinica, P. O. Box 821, Nanjing 210008 ( China) 《Pedosphere》 SCIE CAS CSCD 1993年第2期161-172,共12页
Different mathematical methods, including linearization, differential, integration and nonlinear least squares approximation (Newton-Marquardt method), were used to fit different kinetic equations, such as zero-order,... Different mathematical methods, including linearization, differential, integration and nonlinear least squares approximation (Newton-Marquardt method), were used to fit different kinetic equations, such as zero-order, first-order (i. e, membrane diffusion), second-order, parabolic-diffusion, Elovich, two-constant equations, to the experimental data of Pb2+ and Cu2+ adsorption on variable charge soils and kaolinite. Assuming each M2+ occupied two adsorption sites, two more equations, the so-called surface second-order equation and third-order equation were derived and compared with the above equations according to the fitting results, which showed that the second-order equation and surface second-order equation, being one equation in different expressions under some conditions, were better than the other equations in describing the Pb2+ and Cu2+ adsorption kinetics, and the latter was the best. 展开更多
关键词 adsorption kinetics EQUATIONS heavy metals MODELS variable charge soils
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Relationship Between Soil Boron Adsorption Kinetics and Rape Plant Boron Response 被引量:2
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作者 ZHUDUANWEI PIMEIMEI 《Pedosphere》 SCIE CAS CSCD 1997年第3期269-274,共6页
The boron adsorption kinetic experiment in soil by means of a flow displacement technique showed that the kinetic data could be described with some mathematic equations. The average values of the correlation coefficie... The boron adsorption kinetic experiment in soil by means of a flow displacement technique showed that the kinetic data could be described with some mathematic equations. The average values of the correlation coefficient for zero-order, first-order, parabolic diffusion, Elovich, power function and exponential equations were 0.957, 0.982, 0.981, 0.984, 0.981 and 0.902, respectively. The correlation between adsorbed boron or its other expression form and time were the highest for first-order, parabolic diffusion, Elovich, and power function equations, the second for the zeroorder equation, and the lowest for the exponential equation. The parabolic diffusion equation fitted well the experimental results, with the least standard error among the six kinetic equations, showing that the movement of boron from soil solution to soil colloid surface may be controlled by boron diffusion speed. The boron content of rape seedling obtained from soil cultivation was correlated with the rate constants of the kinetic equations. The constants of first-order, parabolic diffusion,and exponential equations were significantly correlated with the boron content of the crop of NPK treatment at a 95% probability level, with correlation coefficients being 0.686, 0.691 and 0.641, respectively. In the case of zero-order equation, it was significant at 99% probability level (r =0.736). These results showed that the absorption kinetic constants of soil boron were closely related with the rape plant response to boron. 展开更多
关键词 adsorption kinetics plant boron content rate constant soil boron
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Adsorption Kinetics of Alkyl Polyglucoside at the Air-Solution Interface 被引量:2
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作者 JinLingCHAI GaoYongZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第7期670-673,共4页
The air-solution equilibrium tension ge and dynamic surface tension gt, of nonionic surfactant alkyl polyglucoside have been studied. ge was measured by the Wilhelmy method with Krüss K12 tensiometer. The CMC a... The air-solution equilibrium tension ge and dynamic surface tension gt, of nonionic surfactant alkyl polyglucoside have been studied. ge was measured by the Wilhelmy method with Krüss K12 tensiometer. The CMC and the surface excesses Γwere determined from the surface tension vs. concentration curve. The gt decays were measured in the range 0.2~20 s using a maximum bubble pressure instrument and analyzed with the Ward and Tordai equation. 展开更多
关键词 Dynamic surface tension adsorption kinetics alkyl polyglucoside.
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Kinetic and Thermodynamic Studies on Raney Ni/Al2O3 Adsorption for Deep Desulfurization of Benzene Stream 被引量:2
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作者 Cao Yongzheng Luo Guohua +4 位作者 Zhang Lanxi Xu Xin Jin Haibo Dong Sen Guo Xuehua 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第2期71-78,共8页
How to remove trace amount of sulfur in benzene is of significance,and deep desulfurization by Ni-containing absorbents is an efficient and promising method.In this paper,The Raney Ni/Al2 O3 adsorbent was prepared and... How to remove trace amount of sulfur in benzene is of significance,and deep desulfurization by Ni-containing absorbents is an efficient and promising method.In this paper,The Raney Ni/Al2 O3 adsorbent was prepared and its kinetic and thermodynamic characteristics on adsorptive desulfurization of benzene were studied.The results showed that Raney Ni/Al2 O3 adsorbent exhibited good adsorption performance.The equilibrium isotherms indicated that the adsorption of thiophene over the Raney Ni/Al2 O3 adsorbent complied with the Freundlich model.The results of adsorption kinetics studies showed that the pseudo-second-order kinetics equation was more advantageous than the pseudo-first-order kinetics equation in describing the adsorption kinetics of thiophene on Raney Ni/Al2 O3.The rate constant value(kp)was positively correlated with the temperature whereas the adsorption mass transfer process was mainly determined by the intraparticle and film diffusion.The adsorption thermodynamic analysis proved that△G^0<0,△H^0>0,and△S^0>0,implying that the adsorption was a spontaneous,entropy-increasing and endothermic process. 展开更多
关键词 Raney Ni/Al2O3 DESULFURIZATION adsorption kinetics adsorption thermodynamic
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Nickel(Ⅱ) removal from water using silica-based hybrid adsorbents:Fabrication and adsorption kinetics 被引量:3
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作者 Min Xu Junsheng Liu +2 位作者 Keyan Hu Congyong Xu Yaoyao Fang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第10期1353-1359,共7页
A series of novel silica-based hybrid adsorbents were prepared by the crosslinking reaction of N-[3- (trimethoxysilyl)propyl] ethylene diamine (TMSPEDA) with epichlorohydrin (ECH) via a sol-gel process. Fourier ... A series of novel silica-based hybrid adsorbents were prepared by the crosslinking reaction of N-[3- (trimethoxysilyl)propyl] ethylene diamine (TMSPEDA) with epichlorohydrin (ECH) via a sol-gel process. Fourier transform infrared (FTIR) spectra confirmed that the reaction occurred. TGA curves showed that the thermal stability of these hybrid adsorbents reached as high as 180 ℃. As a typical example, the adsorption performance of nickel(U) ions onto an adsorbent (the volume ratio of TMSPEDA and ECH was 4:1 ) was explored. It was found that the adsorption of nickel(Ⅱ) ions onto this adsorbent followed the Lagergren pseudo-second-order kinetic model. The investigation of the adsorption mechanism demonstrated that nickel(Ⅱ) adsorption was chiefly controlled by diffusion-chemisorption, suggesting that more diffusion processes were involved in the adsorption of nickel(Ⅱ) ions onto this type of adsorbents. Desorption experiment indicates that these hybrid adsorbents can be regenerated. These findings reveal that this type of silica-based hybrid adsorbent is promising in the separation and recovery of nickel(Ⅱ) ions from Ni-containing wastewater or contaminated water. 展开更多
关键词 Hybrid adsorbent Nickel(Ⅱ)kinetics adsorption Adsorbent
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Diffusion-controlled Adsorption Kinetics at Air/Solution Surface Studied by Maximum Bubble Pressure Method 被引量:1
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作者 刘俊吉 王创业 MESSOW Ulf 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期577-581,共5页
In studying the diffusion-controlled adsorption kinetics of aqueous surfactant solutions at the air/solution surface by means of the maximal bubble pressure method, Fick's diffusion equation for a sphere should be... In studying the diffusion-controlled adsorption kinetics of aqueous surfactant solutions at the air/solution surface by means of the maximal bubble pressure method, Fick's diffusion equation for a sphere should be used. In this paper the equation was solved by means of Laplace transformation under different initial and boundary conditions. The dynamic surface adsorption F(t) for a surfactant solution, which was used to describe the diffusion-controlled adsorption kinetics at the solution surface, was derived. Different from the planar surface adsorption, the dynamic surface adsorption F(t) for the short time consists of two terms: one is the same as Ward-Tordai equation and the other reflects the geometric effect caused by the spherical bubble surface. This effect should not be neglected for the very small radius of the capillary. The equilibrium surface tension γeq and the dynamic surface tension γ(t) of aqueous C10E6 [CH3(CH2)9(OCH2CH2)6OH] solution at temperature 25℃ were measuredby means of Wilhelmy plate method and maximal bubble pressure method respectively. As t→ 0, the theoreticalanalysis is in good agreement with experimental results and the dependence of γ(t) on is linear. 展开更多
关键词 diffusion-controlled adsorption kinetics dynamic surface tension maximum bubble pressure method
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Thermodynamic and Kinetic Studies of Effective Adsorption of 2,4,6-trichlorophenol onto Calcine Mg/Al-CO_3 Layered Double Hydroxide 被引量:2
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作者 张丹 ZHAO Guoqing +3 位作者 YU Jingang YAN Tao ZHU Mingyue 焦飞鹏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第6期1211-1218,共8页
Adsorption of 2, 4, 6-trichlorophenol(TCP) onto the calcined Mg/Al-CO_3 layered double hydroxide(CLDH) was investigated. The prepared Mg/Al-CO_3 layered double hydroxide(LDH) and CLDH were characterized by powde... Adsorption of 2, 4, 6-trichlorophenol(TCP) onto the calcined Mg/Al-CO_3 layered double hydroxide(CLDH) was investigated. The prepared Mg/Al-CO_3 layered double hydroxide(LDH) and CLDH were characterized by powder X-ray diffraction(XRD) and thermo gravimetric analyzer-differential scanning calorimeters(TG-DSC). Moreover, 2,4,6-trichlorophenol(TCP) was removed effectively(94.7% of removal percentage in 9h) under the optimized experimental conditions. The adsorption kinetics data fitted the pseudosecond-order model well. The Freundlich, Langmuir, and Tempkin adsorption models were applied to the experimental equilibrium adsorption data at different temperatures of solution. The adsorption data fitted the Freundlieh adsorption isotherm with good values of the correlation coefficient. A mechanism of the adsorption process is proposed according to the intraparticle diffusion model, which indicates that the overall rate of adsorption can be described as three steps. 展开更多
关键词 2 4 6-trichlorophenol calcined Mg/Al-CO3 layered double hydroxide adsorption isotherm thermodynamic kinetics
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Adsorption of acid and basic dyes by sludge-based activated carbon:Isotherm and kinetic studies 被引量:3
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作者 李鑫 王广智 +2 位作者 李伟光 王萍 宿程远 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期103-113,共11页
A batch experiment was conducted to investigate the adsorption of an acid dye(Acid Orange 51) and a basic dye(Safranine) from aqueous solutions by the sludge-based activated carbon(SBAC). The results show that the ads... A batch experiment was conducted to investigate the adsorption of an acid dye(Acid Orange 51) and a basic dye(Safranine) from aqueous solutions by the sludge-based activated carbon(SBAC). The results show that the adsorption of Acid Orange 51 decreases at high p H values, whereas the uptake of Safranine is higher in neutral and alkaline solutions than that in acidic conditions. The adsorption time needed for Safranine to reach equilibrium is shorter than that for Acid Orange 51. The uptakes of the dyes both increase with temperature increasing, indicating that the adsorption process of the dyes onto SBAC is endothermic. The equilibrium data of the dyes are both best represented by the Redlich-Peterson model. At 25 °C, the maximum adsorption capacities of SBAC for Acid Orange 51 and Safranine are 248.70 mg/g and 525.84 mg/g, respectively. The Elovich model is found to best describe the adsorption process of both dyes, indicating that the rate-limiting step involves the chemisorption. It can be concluded that SBAC is a promising material for the removal of Acid Orange 51 and Safranine from aqueous solutions. 展开更多
关键词 sludge-based activated carbon Acid Orange 51 Safranine adsorption isotherms kinetics
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Kinetics and Mechanism of Adsorption of Phosphate on Fluorine-containing Calcium Silicate 被引量:1
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作者 朱新华 zhang zhao 沈俊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第2期321-327,共7页
The nanowires-reticulated calcium silicate with a specific surface area more than 100 m^2/g was prepared by a hydrothermalprocess using hydrated lime(Ca(OH)_2,HL)and silica containing soluble fluoride,which was a ... The nanowires-reticulated calcium silicate with a specific surface area more than 100 m^2/g was prepared by a hydrothermalprocess using hydrated lime(Ca(OH)_2,HL)and silica containing soluble fluoride,which was a by-product of fluorine industry,and the soluble fluoride in raw silica was fixed as CaSiF_6 at the same time.The kinetic characteristics and mechanism of adsorbing phosphate by fluorine-containing calcium silicate were investigated in the experiments of phosphorus(P)removalfrom aqueous solution.The results show that the prepared fluorine-containing calcium silicate has excellent performance for adsorbing phosphate,the adsorption process appears to follow pseudo-second-order reaction kinetics and the process is mainly controlled by chemisorption.The product resulted from P adsorption is mainly composed of hydroxyapatite(HAP)and fluorapatite(FAP),which are further used as adsorbents of heavy metalion Cd^(2+) in aqueous solution and display excellent performance. 展开更多
关键词 calcium silicate P adsorption Cd^(2+) adsorption reaction kinetics adsorption mechanism
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Kinetics comparison on simultaneous and sequential competitive adsorption of heavy metals in red soils 被引量:2
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作者 王艳 李忠武 +4 位作者 黄斌 蒋卫国 郭亮 黄金权 曾光明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1269-1275,共7页
To compare the adsorption kinetics of Cu, Zn and Cd introduced into red soils simultaneously and sequentially as well as their distribution coefficients, the ability of red soils to retain heavy metals was evaluated b... To compare the adsorption kinetics of Cu, Zn and Cd introduced into red soils simultaneously and sequentially as well as their distribution coefficients, the ability of red soils to retain heavy metals was evaluated by performing batch experiments. The results indicate that Cu is preferentially adsorbed by red soils no matter in simultaneous or in sequential situation. The adsorption amount of Cd is the minimum in simultaneous competitive adsorption experiment. As heavy metals are added into red soils sequentially, the heavy metal adsorptions are relatively hard to reach equilibrium in 2 h. Red soils retain more Cd than Zn, which is opposite to the result in simultaneous adsorption. The addition sequences of heavy metals affect their adsorbed amounts in red soils to a certain extent. The joint distribution coefficients of metals in simultaneous adsorption are slightly higher than those in sequential adsorption. 展开更多
关键词 kinetics simultaneous system sequential system competitive adsorption red soils
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Heterogeneity of Adsorption Sites and Adsorption Kinetics of n-Hexane on Metal–Organic Framework MIL-101(Cr) 被引量:1
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作者 孙雪娇 苗晋朋 +2 位作者 肖静 夏启斌 赵祯霞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第9期962-967,共6页
The heterogeneity of adsorption sites and adsorption kinetics of n-hexane on a chromium terephthalate-based metal-organic framework MIL-10^1 (Cr) were studied by gravimetric method and temperature-programmed desorpt... The heterogeneity of adsorption sites and adsorption kinetics of n-hexane on a chromium terephthalate-based metal-organic framework MIL-10^1 (Cr) were studied by gravimetric method and temperature-programmed desorption (TPD) experiments. The MIL-101 crystals were synthesized by microwave irradiation method. The ad- sorption isotherms and kinetic curves of n-hexane on the MIL-101 were measured. Desorption activation energies of n-hexane from the MIL-10^1 were estimated by TPD experiments. The resulthowed that equilibrium amount ofn-hexane adsorbed on the MIL-10^1 was up to 5.62 mmol.g- 1 at 298 K and 1.6 x10^4 Pa, much higher than that of some activated carbons, zeolltes and so on. The isotherms of n-hexane on the MIL-101 could be well fitted with Langmuir-Freundlich model. TPD spectra exhibit two types of adsorption sites on the MIL-101 with desorption activation energies of 39.41 and 86.69 kJ. mol-1. It reflects the surface energy heterogeneity on the MIL-10I frameworks for n-hexane adsorption. The diffusion coefficients of n-hexane are in the range of (1.35- 2.35 ) x 10 - 1 o cm2. s - 1 with ad sorotion activation enerv of 16.33 kl. mol - 1. 展开更多
关键词 adsorption kinetics n-Hexane MIL-101 Heterogeneity
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Adsorption Kinetics of Decanoyl-N-methylglucamine at the Expanding Spherical Surface
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作者 刘俊吉 张瑜 李国庭 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期736-740,共5页
A general expression of the dynamic surface adsorption [Г(t)] on the expanding spherical surface was derived by solving the corresponding diffusion equation under different initial and boundary conditions. Differen... A general expression of the dynamic surface adsorption [Г(t)] on the expanding spherical surface was derived by solving the corresponding diffusion equation under different initial and boundary conditions. Different from the result of the still spherical surface, two factors (smaller than 1) appeared in the equation for the short time adsorption. Using the derived results, the adsorption kinetics of aqueous decanoyl-N-methylglucamine (Mega-10) solution was studied. In the short time region (t→0), a good agreement of experimental results with the theory was reached and the adsorption was controlled by diffusion. 展开更多
关键词 adsorption kinetics dynamic surface adsorption expanding spherical surface
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