Application of the GAB Sorption Isotherm Model to Klinki Pine (Araucaria klinkii Lauterb.)

Holzforschung ◽  
2000 ◽  
Vol 54 (6) ◽  
pp. 661-663 ◽  
Author(s):  
I.D. Hartley
Keyword(s):  
Sorption Isotherm ◽  
Isotherm Model

scholarly journals Sorption Isotherm Model of Zinc (II) onto Thermally Treated Rice Husk

2016 ◽  
Vol 32 (5) ◽  
pp. 2797-2801
Author(s):  
Ahmad Tarmizi ◽  
Keat Ong ◽  
Wan Yunus ◽  
Anwar Fitrianto ◽  
Mohd Jabit ◽  
...  
Keyword(s):  
Sorption Isotherm ◽  
Rice Husk ◽  
Isotherm Model ◽  
Thermally Treated

scholarly journals Sorption of Monothioarsenate to the Natural Sediments and Its Competition with Arsenite and Arsenate

2021 ◽  
Vol 18 (23) ◽  
pp. 12839
Author(s):  
Huimei Shan ◽  
Jinxian Zhang ◽  
Sanxi Peng ◽  
Hongbin Zhan ◽  
Danxue Liao
Keyword(s):  
Sorption Isotherm ◽  
Freundlich Isotherm ◽  
Arsenic Species ◽  
Isotherm Model ◽  
Maximum Adsorption Capacity ◽  
High Concentration ◽  
Competitive Effects ◽  
Subsurface Environment ◽  
Intermediate Time ◽  
Langmuir Isotherm Model

Monothioarsenate (MTAsV) is one of the major arsenic species in sulfur- or iron-rich groundwater, and the sediment adsorption of MTAsV plays an important role in arsenic cycling in the subsurface environment. In this study, batch experiments and characterization are conducted to investigate the sorption characteristic and mechanism of MTAsV on natural sediments and the influences of arsenite and arsenate. Results show that MTAsV adsorption on natural sediments is similar to arsenate and arsenite, manifested by a rapid early increasing stage, a slowly increasing stage at an intermediate time until 8 h, before finally approaching an asymptote. The sediment sorption for MTAsV mainly occurs on localized sites with high contents of Fe and Al, where MTAsV forms a monolayer on the surface of natural sediments via a chemisorption mechanism and meanwhile the adsorbed MTAsV mainly transforms into other As species, such as AlAs, Al-As-O, and Fe-As-O compounds. At low concentration, MTAsV sorption isotherm by natural sediments becomes the Freundlich isotherm model, while at high concentration of MTAsV, its sorption isotherm becomes the Langmuir isotherm model. The best-fitted maximum adsorption capacity for MTAsV adsorption is about 362.22 μg/g. Furthermore, there is a competitive effect between MTAsV and arsenate adsorption, and MTAsV and arsenite adsorption on natural sediments. More specifically, the presence of arsenite greatly decreases MTAsV sorption, while the presence of MTAsV causes a certain degree of reduction of arsenite adsorption on the sediments before 4 h, and this effect becomes weaker when approaching the equilibrium state. The presence of arsenate greatly decreases MTAsV sorption and the presence of MTAsV also greatly decreases arsenate sorption. These competitive effects may greatly affect MTAsV transport in groundwater systems and need more attention in the future.

Determination of Moisture Sorption Isotherm Model for Dried and Fresh Sweet Sorghum [Sorghum bicolor (L.) Moench] Stalks

2017 ◽  
Vol 4 (4) ◽  
pp. 308-312
Author(s):  
Melanie Blanca-Ocreto ◽  
◽  
Arnold R. Elepaño ◽  
Kevin F. Yaptenco ◽  
Ernesto P. Lozada ◽  
...  
Keyword(s):  
Sorghum Bicolor ◽  
Sorption Isotherm ◽  
Sweet Sorghum ◽  
Moisture Sorption ◽  
Isotherm Model ◽  
Moisture Sorption Isotherm ◽  
Sorghum Bicolor L

Examination of Tobacco Hygroscopicity / Über die Hygroskopizität des Tabaks

1965 ◽  
Vol 3 (1) ◽  
Author(s):  
L. Hübschen
Keyword(s):  
Moisture Content ◽  
Sorption Isotherm ◽  
Initial Moisture Content

AbstractThe present paper shows the detectable factors on which a sorption isotherm depends. Even if it is well-known that a sorption isotherm is most essentially conditioned by influences of the respective tobacco variety, other factors, such as temperature, initial moisture content, or fibre dimension, play a part as well. In general, a sorption isotherm constitutes a ''summation'' of such factors and, in the end, a combination of desorption and adsorption if the tobacco is dried or moistened from the average commercial moisture content. The tobacco hysteresis is experimentally investigated and discussed

Competitive adsorption of organic solvents using modified and unmodified calcium bentonite clay mineral

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Organic Solvents ◽  
Competitive Adsorption ◽  
Correlation Factor ◽  
Isotherm Model ◽  
Isotherm Models ◽  
High Concentration ◽  
Dual Purpose ◽  
Calcium Bentonite

Dodecyltrimethylammonium bromide (DTAB)–modified and unmodified calcium bentonite were both used for the competitive adsorption of aromatics (xylene, ethylbenzene and toluene) and petroleum products (gasoline, dual purpose kerosene and diesel) from their aqueous solution. Infrared spectroscopy (IR) and expansion tests (adsorption capacity and Foster swelling) measurement were performed in order to evaluate the performance of the adsorbents. The Foster swelling index and adsorption capacity of the DTAB modified calcium bentonite in the organic solvents follow the trend: xylene > ethylbenzene > toluene > gasoline > dual purpose kerosene (DPK) > diesel > water. However, the adsorption capacity of the adsorbent in diesel outweighed the adsorption capacity in DPK at high concentration of DTAB indicating that diesel has higher affinity for high DTAB concentration than DPK. The percentage removal of the solvent is directly proportional to the concentration of DTAB used in modifying the bentonite as well as the contact time between the adsorbent and the solvent, hence modified calcium bentonite adsorbed a higher percentage of organic solvents than the unmodified calcium bentonite. The adsorption characteristics of both adsorbents improved remarkably after proper agitation of the organic solvents, the unmodified calcium bentonite however adsorbed more water than the modified bentonite. Data obtained from adsorption isotherm models confirms that Freundlich adsorption isotherm model was favored more than Langmuir adsorption isotherm model with the correlation factor (R2) of the former tending more towards unity. The adsorption of ethylbenzene using DTAB modified and unmodified calcium bentonites follow a pseudo second order kinetics mechanism, suggesting that the rate determining step of adsorption involves both the adsorbent and the organic solvent.

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