scholarly journals Role of Sawdust in the Removal of Iron from Aqueous Solution

2017 ◽  
Vol 23 (3) ◽  
pp. 223 ◽  
Author(s):  
H.B. Senin ◽  
O. Subhi ◽  
R. Rosliza ◽  
N. Kancono ◽  
M.S. Azhar ◽  
...  

Sawdust, inexpensive material has been utilized as an absorbent for the removal of iron from aqueous solution for their safe disposal. The adsorption experiments of untreated sawdust (SD) and treated sawdust (SDC) have been carried out at room temperature using the batch test. The Langmuir and Freundlich isotherms were used to observe sorption phenomena of sawdust in the removal of iron. The results indicate that the sawdust was capable in removing iron in aqueous solution. The results have shown that the Langmuir isotherm was found well fitted into the experimental data as compared to the Freundlich isotherm. It was found that, chemisorptions and physisorption were the prime mechanism for the process of adsorption to occur between the sawdust and iron. The results also proved that the acid sulphuric treated sawdust is much better than that of untreated sawdust as an adsorbent for iron.

2012 ◽  
Vol 550-553 ◽  
pp. 2424-2427
Author(s):  
Chung Hsin Wu ◽  
Chao Yin Kuo ◽  
Meng Jia Chen

This study utilizes chitin to remove dissolved Cu(II) from aqueous solutions. The effects of the dissolved Cu(II) concentration, chitin dosage, and pH on adsorption of dissolved Cu(II) by chitin are determined. Adsorption capacity for 20 and 80 mg/L dissolved Cu(II) onto chitin (2 g/L) was 3.86 mg/g and 5.12 mg/g, respectively. The dissolved Cu(II) adsorption percentage increased from 39% to 70% when the chitin dosage was increased from 2 g/L to 4 g/L. The linear correlation coefficients of Langmuir and Freundlich isotherms were obtained. Analytical results demonstrate that the Freundlich isotherm fitted experimental results better than did the Langmuir isotherm. Enthalpy (ΔH0) and entropy (ΔS0) for dissolved Cu(II) adsorption were 8.46 kJ/mol and 123.1 J/mol.K, respectively.


2020 ◽  
Vol 10 (6) ◽  
pp. 6846-6864

The objective was to evaluate the removal of dye using activated carbon, and apply the best condition in the removal of candy reprocessing syrup pigment, as well as to evaluate its influence in the visual aspect of a lollipop. Adsorption capacity tests were performed with the dye diluted with and without sucrose, and from the data, the linearization of the Langmuir and Freundlich isotherms were calculated. The lollipop was prepared with syrup treated with activated carbon and visually evaluated using a panel of untrained tasters. The Freundlich isotherm adjusted more appropriately to the experimental data of the adsorption of the dye diluted in distilled water, while for the dye diluted in sucrose solution, the most suitable model was Langmuir's. The experimental design condition showed the highest adsorptive capacity (26.91 mg.g-1) for the dye diluted in the aqueous solution was at a temperature of 60 ºC and pH 5.5, while for the sucrose-diluted dye solution, was 103.09 mg.g-1, under the same conditions. The visual evaluation of the lollipop indicated the possibility of adding up to 15% of reprocessing syrup. Thus, the use of activated carbon is an alternative to remove the coloring from candy syrup and enable its reuse within the industry.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
I. Osasona ◽  
O. O. Ajayi ◽  
A. O. Adebayo

The feasibility of using powdered cow hooves (CH) for removing Ni2+ from aqueous solution was investigated through batch studies. The study was conducted to determine the effect of pH, adsorbent dosage, contact time, adsorbent particle size, and temperature on the adsorption capacity of CH. Equilibrium studies were conducted using initial concentration of Ni2+ ranging from 15 to 100 mgL−1 at 208, 308, and 318 K, respectively. The results of our investigation at room temperature indicated that maximum adsorption of Ni2+ occurred at pH 7 and contact time of 20 minutes. The thermodynamics of the adsorption of Ni2+ onto CH showed that the process was spontaneous and endothermic. Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models were used to quantitatively analysed the equilibrium data. The equilibrium data were best fitted by Freundlich isotherm model, while the adsorption kinetics was well described by pseudo-second-order kinetic equation. The mean adsorption energy obtained from the D-R isotherm revealed that the adsorption process was dominated by physical adsorption. Powdered cow hooves could be utilized as a low-cost adsorbent at room temperature under the conditions of pH 7 and a contact time of 20 minutes for the removal of Ni(II) from aqueous solution.


Author(s):  
Yasser Hannachi

In this paper, removal of Ni (II) from aqueous solution by finely ground waste sludge (FGWS) was investigated. Waste sludge samples obtained from a varnishes and lacquers industry wastewater treatment plant was dried, ground and pre-treated with 1% H2O2 to improve the biosorption capacity. Kinetics of nickel biosorption onto FGWS was investigated by using the FGWS samples with particle size of 62.2 µm. The pseudo-first and second order rate expressions were used to correlate the experimental data. The kinetic constants were determined for both models and the second order rate expression was found to be more suitable. Three different biosorption isotherms were used to correlate the equilibrium biosorption data and the isotherm constants were determined. The Langmuir isotherm was found to fit the experimental data better than the other tested isotherms. The biosorption capacity (qm) and saturation constant (K) for the Langmuir isotherm showed that finely ground waste sludge has the largest capacity and affinity for removal of Ni(II) compared to the other Activated sludges. Santrauka Nagrinėjami Ni(II) šalinimo iš vandeninių tirpalų smulkiai sumaltu nuotekų dumblu (SSND) tyrimų rezultatai. Nuotekų dumblo pavyzdžiai imti iš glazūravimo ir lakavimo pramonės nuotekų valymo įrenginių, išdžiovinti, susmulkinti ir apdoroti 1% H2O2, kad padidėtų biosorbcijos tūris. Nikelio sorbcijos SSND kinetika tirta naudojant SSND bandinius, kurių dalelių dydis 62,2 µm. Pseudo pirmojo ir antrojo laipsnio greičio išraiškos buvo taikomos eksperimentinių duomenų koreliacijai apibrėžti. Kinetinė konstanta nustatyta abiejų modelių, tačiau antrojo laipsnio greičio išraiška buvo tinkamesnė. Pagal tris skirtingas biosorbcijos izotermes nustatyta biosorbcijos pusiausvyros duomenų koreliacija, rastos izotermių konstantos. Langmiuro (Langmuir) izotermė geriau atitiko eksperimentinius duomenis nei kitos tirtosios izotermės. Pagal Langmiuro izotermę biosorbcijos geba (q m) ir prisotinimo konstanta (K) rodė, kad smulkiai sumalto nuotekų dumblo geba šalinti Ni(II) yra didžiausia, palyginti su kitos rūšies aktyvintojo dumblo. Резюме Исследуется удаление Ni(II) из водных растворов мелко измельченным илом стоков (МИИС). Образцы ила стоковбыли взяты из оборудования по очистке стоков в промышленности по глазурованию и лакованию. Затем образцы были высушены, измельчены и обработаны 1-процентным H2O2, с целью увеличить объем биосорбции. Кинетика сорбции никеля МИИС исследовалась с применением образцов МИИС, величина частиц которых составляла62,2 μм. Выражения скорости псевдопервой и псевдовторой степени использовались для определения корреляции экспериментальных данных. Кинетическая константа была установлена для обеих моделей. Однако выражение скорости второй степени оказалось более приемлемым. Три разные изотермы биосорбции применялись для определения корреляции данных по равновесию биосорбции и констант изотерм. Изотерма Langmuir лучше совпала с экспериментальными данными, чем другие испытуемые изотермы. Способность биосорбции (q m) изотермы Langmuir и константа насыщения (K) показали, что мелко измельченный ил стоков обладает наибольшей способностью удалять Ni(II) по сравнению с другими видами активированного ила.


1977 ◽  
Vol 55 (11) ◽  
pp. 2009-2016 ◽  
Author(s):  
G. A. Kenney-Wallace

The role of the fluid is considered for a model of electron solvation in liquid alcohols. The events that lead to trapping and solvation of excess electrons are reconstructed from experimental data on the time and frequency-dependent electron absorptions (kmol) and the appropriate molecular rotational relaxations (τ2, τc), local liquid structure, viscosity (η), and orientational polarization (β) of the supporting fluid. The quasifree electron is captured at subpicosecond times in a preexisting trap in the liquid, which in alcohols is identified as an alcohol cluster whose local configurational fluctuations will be frozen in on this timescale. Rapid configurational relaxation of the cluster molecules, including multi-phonon processes, then occurs in the field of the excess electron at times ≤10−12 s. Finally, the molecules in the fluid layer adjacent to the initial trapping site align in the now screened field of the localized electron in a manner comparable to solvation of an ion embedded in a polar fluid. The relaxation may occur in competition with electron migration and reaction. The observed rate constant of the final step kmol is shown to be proportional to βη−1 for a range of alcohols at room temperature. The implications of this model for photobleaching experiments in liquids are briefly discussed.


Nano LIFE ◽  
2015 ◽  
Vol 05 (03) ◽  
pp. 1542005 ◽  
Author(s):  
Lu Fan ◽  
Ling Li ◽  
Keke Sun ◽  
Lebao Mao ◽  
Keke Liang ◽  
...  

The adsorption of malachite green from an aqueous solution of magnetic Fe 3 O 4 was studied in view of the adsorption isotherm, kinetics and regeneration of the sorbent. The adsorption isotherm of MG on nano- Fe 3 O 4 composite followed the Langmuir isotherm. Adsorption kinetics was determined from the experimental data. The nano- Fe 3 O 4 can be recycled for reuse after regeneration through acetonitrile. The high adsorption capacity and excellent reusability made Fe 3 O 4 attractive for the removal of MG from aqueous solution.


2021 ◽  
Vol 10 (2) ◽  
pp. 36-42
Author(s):  
Duyen Le Thi ◽  
Hanh Vo Thi ◽  
Dung Cong Tien ◽  
Thanh Dinh Thi Mai

Hydroxyapatite/chitosan nanocomposite (n-HAp/ChS) was synthesized successfully from 0.5 M Ca(NO3)2 + 5 % chitosan/2 % acetic acid solution and 0.3 M (NH4)2HPO4 solution at pH 10-11 using 28 % NH3 solution by chemical precipitation method. n-HAp/ChS was used for the adsorption of Cd2+ from aqueous solution. The effect of factors on the Cd2+ adsorption efficiency and capacity was investigated. The adsorption efficiency and capacity obtained 97,75 % and 58,65 mg/g respectively at suitable condition: pH0 5.9,n-HAp/ChS mass of 0.1 g, initial Cd2+ concentration of 60 mg/L, contact time 40 minutes at room temperature (30oC). The experimental data was described by Langmuir and Freundlich isotherm models.


2019 ◽  
Vol 32 (2) ◽  
pp. 311-316
Author(s):  
Rino Laly Jose ◽  
M.G. Gigimol ◽  
Beena Mathew

N,N-Methylene bis-acrylamide crosslinked poly-N-vinyl pyrrolidone hydrogels were synthesized and binding of the hydrogel with the dye solution was followed spectrophotometrically. The chemical structure and morphology of the hydrogel before and after adsorption of acid black 194 was confirmed by FT-IR and SEM. Effect of various physico-chemical parameters such as concentration, temperature, pH, time and the amount of hydrogel used were investigated by batch adsorption studies. Hydrogel used as adsorbent in this study was characterized by UV-Vis spectrophotometer before and after adsorption of acid black 194. Kinetic studies suggested pseudo second order reaction. Langmuir and Freundlich isotherms were applied on equilibrium adsorption data and found that Freundlich isotherm fit better for the present investigation. N,N-methylene bisacrylamide crosslinked poly-N-vinyl pyrrolidone hydrogel displayed excellent properties for the removal of the azo dye, acid black 194 from aqueous solution.


2013 ◽  
Vol 448-453 ◽  
pp. 1408-1411
Author(s):  
Dan Fu

In this paper, the adsorption properties of oil-containing wastewater on Fly Ash (FA)were investigated. The effects of contact time, adsorbent dosage, pH value and the temperature were examined. The equilibrium adsorption data are analyzed using Langmuir and Freundlich isotherms. The Langmuir isotherm fits the experimental results well. The study indicates that FA is a potential adsorbent for oil-containing wastewater treatment.


2021 ◽  
Vol 19 (49) ◽  
pp. 1-6
Author(s):  
Amir Abdullah Mohammed ◽  
Hayder Saleem Hussain ◽  
Salam K. Abdullah

  Prepared zeolite type A was used for the removal of cesium ions from aqueous solution. The experimental data were analyzed by Langmuir, Freundlich isotherms. Various parameters, such as contact time, zeolite weight, pH, and initial concentration, were studied The results indicated that the highestt removal efficiency was  95.53% at (2h time, 0.04 g weight, and pH=6.8). The results also showed that the Freundlic model fits well with the experimental results and is better than the Langmuir model.


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