Absorption Behavior of Methanol Vapor on the Silica Gels

2020 ◽  
Vol 1003 ◽  
pp. 156-162
Author(s):  
Ke Le Yan ◽  
Yu Lin ◽  
Wang Qian
Keyword(s):  
Experimental Data ◽  
Adsorption Equilibrium ◽  
Langmuir Equation ◽  
Silica Gels ◽  
Equilibrium Equations ◽  
Methanol Vapor ◽  
Freundlich Equation ◽  
Adsorption Capacities ◽  
Adsorption Data ◽  
The Rich

The adsorption behavior of methanol vapor onto three commercial silica gels named SG-1, SG-2 and SG-3 were investigated in this paper. The experimental results showed that SG-1 has the rich microporous, and the larger surface area and microporous volume than SG-2 and SG-3. The equilibrium adsorption data showed that the adsorption capacities of SG-1 was superior to SG-2 and SG-3 for lower concentration of methanol (<150 g/m3). However, SG-2 had higher adsorption capacities than SG-1 and SG-3 for higher concentration of methanol resulting from the condensation in mesopore channels. Three kinds of adsorption equilibrium equations including Langmuir equation, Freundlich equation and Dubinin-Astakov (D-A) equation were used to fit the methanol vapor adsorption isotherms. The results indicated that the experimental data can be well-fitted by D-A equation.

scholarly journals Adsorption of As(V) and As(III) from aqueous solution by lepidocrocite (γ-FeOOH) nanoparticle

2016 ◽  
Vol 19 (4) ◽  
pp. 270-281
Author(s):  
Trung Dinh Nguyen ◽  
Phuong Dong Truong
Keyword(s):  
Adsorption Equilibrium ◽  
Reaction Model ◽  
Precipitation Method ◽  
Second Order Reaction ◽  
High Adsorption ◽  
Freundlich Isotherms ◽  
Adsorption Capacities ◽  
Adsorption Data ◽  
Pseudo Second Order ◽  
Co Precipitation

γ-FeOOH nanorods an adsorbent for As(V) and As(III) removal was prepared by a chemical co-precipitation method. The maximum adsorption capacities at pH6 for As(V) and As(III) were 63.75 and 88.99 mg/g, respectively, higher than those of Fe2O3, Fe3O4... The adsorption data accorded with Freundlich isotherms. At the study pH, for arsen, the adsorption equilibrium was gained after 90 min. Kinetic data fitted well to the pseudo-second-order reaction model. The adsorption of γ-FeOOH for As (V) and As(III) could be competed by some other ion such as sulfate, ammonium and chloride. The high adsorption capability and good performance on other aspects make the γ-FeOOH nanorod a promissing adsorbent for the removal of As (V) and As(III) from the groundwater.

scholarly journals Adsorption of Para Substituted Anilines from Cyclohexane Solution on Sepiolite

1987 ◽  
Vol 4 (1-2) ◽  
pp. 79-85 ◽  
Author(s):  
E. Gonzalez-Pradas ◽  
A. Valverde-Garcia ◽  
M. Villaranca-Sanchez ◽  
F. Del ◽  
Rey Bueno
Keyword(s):  
Experimental Data ◽  
Adsorption Isotherms ◽  
Equilibrium Constants ◽  
Langmuir Equation ◽  
Substituted Anilines ◽  
Surface Areas ◽  
Adsorption Capacities ◽  
Adsorption Processes ◽  
Data Points ◽  
Apparent Equilibrium

The adsorption processes of different para-substituted anilines from cyclohexane solution on natural sepiolite have been studied. The adsorption isotherms may be classified as type L-2 of the Giles classification in the p-bromoaniline and p-toluidine cases, and as type H-2 in the p-acetylaniline case. The experimental data points have been fitted to the Langmuir equation and the adsorption capacities, surface areas available to the amine molecules and apparent equilibrium constants have been calculated. The apparent thermodynamic magnitudes corresponding to the adsorption processes have also been determined.

scholarly journals Biosorptive Detoxification of Cosmos Red Dye by Raphinus Sativus Leaves and Citrus sinensis Peels from Water in Cost Efective and Ecofriendly Way

2020 ◽  
Vol 71 (6) ◽  
pp. 238-246
Author(s):  
Rabia Rehman ◽  
Maryam Qaseem ◽  
Liviu Mitu
Keyword(s):  
Aqueous Medium ◽  
Langmuir Isotherm ◽  
Citrus Sinensis ◽  
Adsorption Equilibrium ◽  
Low Cost ◽  
Orange Peels ◽  
Adsorption Capacities ◽  
Adsorption Data ◽  
Red Dye ◽  
Efficient Adsorbent

The purpose of this study was batch scale elimination of Cosmos Red dye from aqueous medium by low cost and environmentally friendly adsorbents. To study the dye removing capacity, leaves of Raphinus sativus (radish) and peels of Citrus sinensis (orange) were utilized. Two adsorption isotherms were studied to explain adsorption equilibrium. The Langmuir isotherm is compatible to adsorption data. Best adsorption capacities for Raphinus sativus and Citrus sinensis were: 3.437 mg/g and 5.844 mg/g correspondingly. Citrus sinensis peels showed more adsorption. The negative values of thermodynamic parameters ∆Go for both adsorbents have shown the feasibility of this process. The results had shown that for removal of Cosmos Red dye, Citrus sinensis (orange) peels are more efficient adsorbent as compared to Raphinus sativus leaves.

Comparative study of isotherm parameters of lead biosorption by two wastes of olive-oil production

2015 ◽  
Vol 72 (5) ◽  
pp. 711-720 ◽  
Author(s):  
G. Blázquez ◽  
A. Ronda ◽  
M. A. Martín-Lara ◽  
A. Pérez ◽  
M. Calero
Keyword(s):  
Experimental Data ◽  
Olive Tree ◽  
Langmuir Equation ◽  
Equilibrium Isotherm ◽  
Chemical Treatments ◽  
Olive Stone ◽  
Loss Of Mass ◽  
Best Fit ◽  
Tree Pruning ◽  
Effectiveness Coefficient

Batch isotherm studies were carried out on a laboratory scale: (i) to investigate the effectiveness to remove lead of two wastes (olive stone (OS) and olive tree pruning (OTP)), untreated and chemically treated; and (ii) to examine the applicability of various adsorption isotherms to fit the experimental data. Results from tests were analyzed using seven equilibrium isotherm correlations (Langmuir, Freundlich, Dubinin–Radushkevich, Temkin, Redlich–Peterson, Sips, and Toth equations). The sum of the squares of the errors was determined for each isotherm and the Langmuir equation provided the best fit. Chemical treatments increased the biosorption properties of these materials. The maximum biosorption capacities were: 6.33, 49.13, 14.83, and 38.93 mg g−1 for untreated OS, HNO3-OS, H2SO4-OS, and NaOH-OS, respectively, and 26.72, 86.40, 72.78, and 123.80 mg g−1 for untreated OTP, HNO3-OTP, H2SO4-OTP, and NaOH-OTP, respectively. Finally, the loss of mass for each waste (13.9, 14.3, and 36.8% for HNO3-OS, H2SO4-OS, and NaOH-OS and 35.1, 27.5, and 46.7% for HNO3-OTP, H2SO4-OTP, and NaOH-OTP, respectively) was taken into account and an effectiveness coefficient was determined for each adsorbent material.

scholarly journals The study of phosphate ions sorption from silicon dioxide solutions obtained by using acid decomposition of nepheline

2021 ◽  
Vol 12 (2-2021) ◽  
pp. 42-47
Author(s):  
Yu. O. Velyaev ◽  
◽  
D. V. Maiorov ◽  
Keyword(s):  
Experimental Data ◽  
Silicon Dioxide ◽  
Equilibrium Constant ◽  
Municipal Wastewater ◽  
Adsorption Equilibrium ◽  
Sorption Process ◽  
Acid Decomposition ◽  
Phosphate Ion ◽  
Phosphate Ions ◽  
Adsorption Monolayer

The process of sorption of phosphate ion by silicon dioxide obtained by acid decomposition of nepheline is studied. The experimental data were processed using the Freundlich and Langmuir sorption equations, which showed that the sorption process is fairly accurately described by both equations, while the use of the Langmuir monomolecular adsorption equation is preferable in the calculations. The capacity of the adsorption monolayer of the synthesized sample relative to the РО43–-ion and the adsorption equilibrium constant are calculated. Based on the obtained data, various options for sorption treatment of municipal wastewater from РО43--ion to normalized MPC values were evaluated.

scholarly journals Adsorption Equilibrium of 1, 1-Dichloro-1-fluoroethane (HCFC-141b) on a Hydrophobic Zeolite

1998 ◽  
Vol 16 (2) ◽  
pp. 67-75 ◽  
Author(s):  
Wen-Tien Tsai ◽  
Ching-Yuan Chang ◽  
Chih-Yin Ho
Keyword(s):  
Experimental Data ◽  
Free Energy ◽  
Thermodynamic Properties ◽  
Adsorption Isotherms ◽  
Ozone Depletion ◽  
Adsorption Equilibrium ◽  
Stratospheric Ozone ◽  
Stratospheric Ozone Depletion ◽  
Equilibrium Isotherms ◽  
Entropy Of Adsorption

Of the major replacements for chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) are now accepted as being prime contributors to stratospheric ozone depletion. As a consequence, the development of adsorbents capable of adsorbing and recovering specific HCFCs has received great attention. This paper describes an investigation of the adsorption equilibrium of 1, 1-dichloro-1-fluoroethane (HCFC-141b) vapour on a commercial hydrophobic zeolite. The corresponding Henry, Freundlich and Dubinin–Radushkevich (D–R) equilibrium isotherms have been determined and found to correlate well with the experimental data. Based on the Henry adsorption isotherms obtained at 283, 303 and 313 K. thermodynamic properties such as the enthalpy, free energy and entropy of adsorption have been computed for the adsorption of HCFC-141b vapour on the adsorbent. The results obtained could be useful in the application of HCFC adsorption on the hydrophobic zeolite studied.

scholarly journals The Replication Hypothesis along the Take-Off Run and a System of Equilibrium Equations at the Lift-Off of a Protobird

Aerospace ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 21
Author(s):  
Phillip Burgers
Keyword(s):  
Experimental Data ◽  
Time Span ◽  
Flapping Wings ◽  
Equilibrium Equations ◽  
Scaling Down ◽  
Lift Off ◽  
To Come ◽  
System Of Equilibrium Equations

An extant bird resorts to flapping and running along its take-off run to generate lift and thrust in order to reach the minimum required wing velocity speed required for lift-off. This paper introduces the replication hypothesis that posits that the variation of lift relative to the thrust generated by the flapping wings of an extant bird, along its take-off run, replicates the variation of lift relative to the thrust by the flapping wings of a protobird as it evolves towards sustained flight. The replication hypothesis combines experimental data from extant birds with evidence from the paleontological record of protobirds to come up with a physics-based model of its evolution towards sustained flight while scaling down the time span from millions of years to a few seconds. A second hypothesis states that the vertical and horizontal forces acting on a protobird when it first encounters lift-off are in equilibrium as the protobird exerts its maximum available power for flapping, equaling its lift with its weight, and its thrust with its drag.

Adsorption and ion exchange of some groundwater anion contaminants in an amine modified coconut coir

1997 ◽  
Vol 35 (7) ◽  
pp. 89-95 ◽  
Author(s):  
Aloysius U. Baes ◽  
Tetsuji Okuda ◽  
Wataru Nishijima ◽  
Eiji Shoto ◽  
Mitsumasa Okada
Keyword(s):  
Ion Exchange ◽  
Low Cost ◽  
Exchange Capacity ◽  
Batch Adsorption ◽  
Ion Exchange Capacity ◽  
Strong Base ◽  
Chromium Vi ◽  
Freundlich Equation ◽  
Adsorption Data ◽  
Coconut Coir

The adsorption of nitrate, chromium (VI), arsenic (V) and selenium (VI) anions in an amine modified coconut coir (MCC-AE : with secondary and tertiary amine functionality) were studied to determine the capability of this easily prepared and low-cost material in removing typical groundwater anion contaminants. Batch adsorption-ion exchange experiments were conducted using 200 mg MCC-AE, initially containing chloride as the resident anion, and 50 ml of different anion-containing water of varying concentrations. It is presumed, at this low pH, that only SeO42− remained as a divalent anion, while monovalent species H2AsO4− and HCrO4− predominated in their respective exchanging ion solutions. The adsorption data were fitted using the Freundlich equation and maximum adsorption for each anion was estimated using their respective Freundlich equation constants. MCC-AE exhibited preference for divalent Cr (VI) and Se (VI) anions compared with the Cl− resident ion. Maximum As (V) adsorption was 0.086 mmol/g, while maximum adsorption of Cr (VI), NO3− and Se (VI) anions was 0.327 mmol/g, 0.459 mmol/g, and 0.222 mmol/g, respectively. The ion exchange capacity of MCC-AE is estimated, based on its exchange capacity for nitrate, to be within 0.46 mmol of positive charges per gram. Similar adsorption experiments were conducted for comparison using commercial chloride-form Amberlite IRA-900 strong base (quaternary amine functionality) anion exchanger, with an exchange capacity of 4.2 meq/g. Maximum adsorption of the different ions in IRA-900 was about 3 times higher for NO3−, 9 times higher for Se (VI), 10 times higher for As (V) and 9 times higher for Cr (VI), than that in MCC-AE. Differences in the ion exchange behavior of MCC-AE and IRA-900 were probably due to the different amine functionalities in the two exchangers. The results suggest that MCC-AE may be used as a low-cost alternative adsorbent/ion exchanger for treatment of anion contaminants in groundwater.

Lead(II) Adsorption by Raw and Acid-Activated Vermiculite

2012 ◽  
Vol 557-559 ◽  
pp. 1127-1130 ◽  
Author(s):  
Wen Jun Xiang
Keyword(s):  
Specific Surface ◽  
Surface Charge ◽  
Langmuir Isotherm ◽  
Cation Exchange Capacity ◽  
Zero Point ◽  
Exchange Capacity ◽  
Zero Point Of Charge ◽  
Adsorption Capacities ◽  
Adsorption Data ◽  
Hcl Solution

Acid-activated vermiculite (AAV) was prepared by treating raw vermiculite (RV) at 80°C with HCl solution. The surface properties and Pb(II) adsorption characteristics of RV and AAV were studied. The specific surface area (SSA), cation exchange capacity (CEC), pH at zero point of charge (pHZPC), and surface charge at pH 5.8 of AAV were 287.62 m2/g, 24.85 cmol/kg, pH 3.06, and -0.361 mmol/g, respectively. Compared to RV, the SSA, CEC and surface charge of AAV increased, but the value of pHZPC decreased. At pH 5.8, the maximum adsorption capacities (qmax) for Pb(II) of RV and AAV were 10.72 and 18.53 mg/g, respectively. The adsorption data for Pb(II) by RV and AAV could be well fitted using Langmuir isotherm (R2 =0.990 and 0.995, respectively)

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