On the fractality of the Freundlich adsorption isotherm in equilibrium and non-equilibrium cases

2016 ◽  
Vol 18 (30) ◽  
pp. 20784-20789 ◽  
Author(s):  
Przemysław Borys ◽  
Zbigniew J. Grzywna
Keyword(s):  
Adsorption Isotherm ◽  
Freundlich Isotherm ◽  
Fractal Properties ◽  
Freundlich Adsorption Isotherm ◽  
Isotherm Of Adsorption ◽  
Non Equilibrium

This work relates the fractal properties of the adsorbent to the exponent of the Freundlich Isotherm of adsorption.

Simultaneous Adsorption of Trichloroethylene and Cadmium on Attapulgite in the Groundwater

2012 ◽  
Vol 610-613 ◽  
pp. 3202-3205
Author(s):  
Hai Ying Gao ◽  
Xiao Qian Li ◽  
Hui Jie Yan ◽  
Xiao Wei Wang
Keyword(s):  
Adsorption Isotherm ◽  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Adsorption Rate ◽  
Adsorption Time ◽  
Freundlich Adsorption Isotherm ◽  
Effects Of Ph ◽  
Combined Contamination

The adsorption of trichloroethylene (TCE) and Cd2+ combined contamination in the groundwater by attapulgite were studied, and the effects of pH, dosage of attapulgite and adsorption time on adsorption were investigated, equilibrium of the adsorptions processes were further conducted. Results showed that the adsorption rate of TCE affected little by the pH; TCE adsorption equilibrium reached after 3d, the removal rate was 71.34%; when attapulgite dosage was 0.03g, the adsorption rate was up to more than 51.08%. Freundlich isotherm was best fitted the adsorption process of TCE. Compound contamination of TCE and Cd2+ decreased the removal rate of TCE; but was in line with Freundlich adsorption isotherm.

scholarly journals Mesoporous Silica MCM-48 as Chloramphenicol Adsorbent

2021 ◽  
Vol 8 (3) ◽  
pp. 242-246
Author(s):  
Paulina Taba ◽  
Miftahul Jannah ◽  
Yusafir Hala
Keyword(s):  
Adsorption Isotherm ◽  
Mesoporous Silica ◽  
Contact Time ◽  
Freundlich Isotherm ◽  
Freundlich Adsorption Isotherm ◽  
Potential Use

This study is aimed to determine the potential use of MCM-48 to adsorb chloramphenicol pollution. Chloramphenicol adsorption was conducted at various times contact and concentration. Adsorption isotherm was studied by comparing Langmuir and Freundlich adsorption isotherm. The results showed that chloramphenicol adsorption was suited to Freundlich isotherm with an optimum contact time of 80 minutes 

scholarly journals Nonlinear Kinetic and Equilibrium Adsorption Isotherm Study of Cadmium (II) Sorption by Dacryodes edulis Biomass

2021 ◽  
Vol 28 (2) ◽  
pp. 10-19
Author(s):  
L.C. Overah
Keyword(s):  
Adsorption Isotherm ◽  
Active Sites ◽  
Freundlich Isotherm ◽  
Equilibrium Adsorption ◽  
Isotherm Study ◽  
Freundlich Adsorption Isotherm ◽  
Seed Biomass ◽  
Good Potential ◽  
Equilibrium Adsorption Isotherm ◽  
Dacryodes Edulis

The kinetics and equilibrium adsorption isotherm of cadmium (II) adsorption onto Dacryodes edulis (native peer seed) biomass was studied using a nonlinear approach, which is unpopular but proven in some literature to be more reliable and easier. In optimizing the process, about 98% removal of the cadmium ion was achieved within five minutes at pH 7 by contacting just 30 mg of the Dacryodes edulis seed biomass with the adsorbate solution of a concentration of 100 mg/L. Non-linear investigation of the kinetics and adsorption isotherms of the process was done using the R console statistical and computing software. The results indicated that the Elovich mechanism and the Freundlich adsorption isotherm most suitably described the kinetics and adsorption isotherm, respectively, of the process as provided by their least values of the sum of squared residuals (SSR). This outcome implied a chemical adsorption  (chemisorption) mechanism and a multi-layer coverage by the cadmium ions on heterogeneous active sites of the biomass surface with a Freundlich constant or capacity factor, Kf of 27.83 mg g-1, heterogeneity factor, 1/n of 0.2614 and Elovich constants, α and β of 7.0 mg g−1 s−1 and 1.0 g mg-1, respectively. These findings indicate that Dacryodes edulis seed biomass has a good potential for cadmium (II) adsorption. Keywords: Dacryodes edulis, Elovich kinetic model, Freundlich isotherm, Langmuir isotherm, Nonlinear 

scholarly journals Adsorption Study for Trifluralin on Iraqi ? –Alumina

2012 ◽  
Vol 9 (1) ◽  
pp. 153-159 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Adsorption Isotherm ◽  
Aqueous Solutions ◽  
Contact Time ◽  
Adsorption Process ◽  
Kinetic Equations ◽  
Adsorption Study ◽  
Adsorption Capacities ◽  
Experimental Parameters ◽  
Freundlich Adsorption Isotherm ◽  
Equilibrium Adsorption Isotherm

Equilibrium adsorption isotherm for the removal of trifluralin from aqueous solutions using ? –alumina clay has been studied. The result shows that the isotherms were S3 according Giels classification. The effects of various experimental parameters such as contact time, adsorbent dosage, effect of pH and temperature of trifluralin on the adsorption capacities have been investigated. The adsorption isotherms were obtained by obeying freundlich adsorption isotherm with (R2 = 0.91249-0.8149). The thermodynamic parameters have been calculated by using the adsorption process at five different temperature, the values of ?H, ?G and ?S were (_1.0625) kj. mol-1, (7.628 - 7.831) kj.mol-1 and (_2.7966 - _2.9162) kg. k-1. mol-1 respectively. The kinetic study of adsorption process has been studied depending on three kinetic equations: 1- Allergen equation 2- Morris –weber eguation 3- Reichenberg eguation. In general, the result shows the isotherm were on ?- alumina according to Giels classification.? –alumina and thermodynamic

scholarly journals Adsorption Study for Chromium (VI) on Iraqi Bentonite

2010 ◽  
Vol 7 (1) ◽  
pp. 745-756
Author(s):  
Baghdad Science Journal
Keyword(s):  
Adsorption Isotherm ◽  
Adsorption Process ◽  
Kinetic Equations ◽  
Bentonite Clay ◽  
Sorption Process ◽  
Adsorption Study ◽  
Chromium Vi ◽  
Freundlich Adsorption Isotherm ◽  
Different Temperatures ◽  
The Subject

The subject of this research involves studying adsorption to remove hexavalent chromium Cr(VI) from aqueous solutions. Adsorption process on bentonite clay as adsorbent was used in the Cr(VI) concentration range (10-100) ppm at different temperatures (298, 303, 308 and 313)K, for different periods of time. The adsorption isotherms were obtained by obeying Langmuir and Freundlich adsorption isotherm with R2 (0.9921-0.9060) and (0.994-0.9998), respectively. The thermodynamic parameters were calculated by using the adsorption process at four different temperatures the values of ?H, ?G and ?S was [(+6.582 ? +6.547) kJ.mol-1, (-284.560 ? -343.070) kJ.mol-1 and (+0.977 ? +1.117) kJ.K-1.mol-1] respectively. This data indicates the spontaneous sorption process. The kinetic study of adsorption process was studied depending on three kinetic equations: 1- Lagergren equation 2- Morris-Weber equation 3- Reichenberg equation

The Derivation of Freundlich Adsorption Isotherm

Daxue Huaxue ◽  
2015 ◽  
Vol 30 (3) ◽  
pp. 76-79
Author(s):  
Shi Jibin ◽  
◽  
◽  
Liu Guojie
Keyword(s):  
Adsorption Isotherm ◽  
Freundlich Adsorption Isotherm

Adsorption of chromium (VI) from aqueous solutions on activated carbon

1994 ◽  
Vol 30 (9) ◽  
pp. 191-197 ◽  
Author(s):  
R. Leyva Ramos ◽  
A. Juarez Martinez ◽  
R. M. Guerrero Coronado
Keyword(s):  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Ph Effect ◽  
Freundlich Isotherm ◽  
Maximum Adsorption Capacity ◽  
Experimental Adsorption ◽  
Ph Values ◽  
Chromium Vi ◽  
Adsorption Data

The adsorption isotherm of chromium (VI) on activated carbon was obtained in a batch adsorber. The experimental adsorption data were fitted reasonably well to the Freundlich isotherm. The effect of pH on the adsorption isotherm was investigated at pH values of 4, 6, 7, 8, 10 and 12. It was found that at pH < 6, Cr(VI) was adsorbed and reduced to Cr(III) by the catalytic action of the carbon and that at pH ≥ 12, Cr(VI) was not adsorbed on activated carbon. Maximum adsorption capacity was observed at pH 6 and the adsorption capacity was diminished about 17 times by increasing the pH from 6 to 10. The pH effect was attributed to the different complexes that Cr(VI) can form in aqueous solution. The adsorption isotherm was also affected by the temperature since the adsorption capacity was increased by raising the temperature from 25 to 40°C. It was concluded that Cr(VI) was adsorbed significantly on activated carbon at pH 6 and that the adsorption capacity was greatly dependent upon pH.

Experiment Study on Treatment of Chromium(VI)-Containing Groundwater by Modified Synthetic Zeolite

2012 ◽  
Vol 430-432 ◽  
pp. 1253-1256 ◽  
Author(s):  
Yu Jie Huang ◽  
Huan Zhen Zhang
Keyword(s):  
Adsorption Isotherm ◽  
Hexavalent Chromium ◽  
Treatment Effect ◽  
Synthetic Zeolite ◽  
Experiment Study ◽  
Ph Adjustment ◽  
Modified Zeolite ◽  
Solid Ratio ◽  
Chromium Vi ◽  
Freundlich Adsorption Isotherm

In order to improve the removal ability of hexavalent chromium on the synthetic zeolite, the synthetic zeolite was modified by FeSO4, which was used to removal hexavalent chromium in groundwater. The results showed that the concentration of Cr (VI) can be reduced from 5.0mg/l to 0.03 mg/l, which meets the requirements of groundwater standards (0.05mg/l) by using modified zeolite in a liquid-to-solid ratio of 20 ml/g, pH=3 for 120 minutes. The adsorption of Cr (VI) on the modified synthetic zeolite could be described by the Langmuir and Freundlich adsorption isotherm. It is showed that the synthetic zeolite modified by FeSO4 has good treatment effect and after treatment the pH of groundwater can reach around 6.8, which need no more pH adjustment.

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