scholarly journals Removal of Heavy Metals (Fe, Mn and Cd) from Aqueous Solutions by Natural Zeolite and FeS Media

2021 ◽  
Vol 43 (7) ◽  
pp. 524-536
Author(s):  
Sung-kyu Choi ◽  
Min-jun Kim ◽  
Tae-geon Kim ◽  
Tae-jin Lee
Keyword(s):  
Heavy Metals ◽  
Aqueous Solution ◽  
Adsorption Isotherm ◽  
Molecular Diffusion ◽  
Kinetic Characteristic ◽  
Absorption Capacity ◽  
Langmuir Adsorption Isotherm ◽  
Limiting Factor ◽  
Langmuir Adsorption ◽  
Adsorption Characteristics

Objectives : The adsorption characteristics of Fe, Cd, and Mn in aqueous solution using zeolite and FeS media were investigated by the adsorption isotherm and kinetic model analysis.Methods : The adsorption characteristics of the heavy metals (Fe, Mn, Cd) were investigated using Langmuir or Freundlich adsorption isotherm. The analysis of pseudo-first or pseudo-second order reaction was also attempted to evaluate the rate limiting factor such as molecular diffusion or chemical adsorption on the absorbents.Results and discussion : The adsorption of the heavy metals on the zeolite and FeS media was more suitable for the Langmuir adsorption isotherm, representing that mono-layer absorption on the surface and no interaction between the absorbed solutes. The order of adsorption preference to zeolite was Fe > Cd > Mn, whereas the order of adsorption preference to FeS media was Cd > Fe > Mn. The adsorption kinetics of zeolite and FeS media were more suitable for pseudo-secondary reactions than for pseudo-primary reaction.Conclusions : The absorption capacity of FeS media for the heavy metals (Fe, Cd and Mn) in aqueous solution was higher than that of zeolite. The adsorption pattern was suitable for the Langmuir adsorption isotherm, and has kinetic characteristic by chemisorption.

scholarly journals Surface Flocculation as a New Tool for Controlling Adsorption Processes

2002 ◽  
Vol 20 (9) ◽  
pp. 883-896 ◽  
Author(s):  
Miloslav Milichovský ◽  
Bretislav Češek
Keyword(s):  
Aqueous Solution ◽  
Reaction Mechanism ◽  
Adsorption Isotherm ◽  
Adsorption Isotherms ◽  
Colloidal Particles ◽  
Langmuir Adsorption Isotherm ◽  
Cellulose Fibres ◽  
Langmuir Adsorption ◽  
Low Degree ◽  
Adsorption Processes

The dyeing of modified pulp, particularly with regard to the mechanism involved, was studied. The reaction mechanism for the modification of cellulose fibres in aqueous solution by cationic agents was also described. The results obtained were expressed in the form of adsorption isotherms. The capture of molecules, colloidal particles, etc. during the adsorption processes involving modified pulp could be explained by two possible mechanisms: (i) aggregation (coagulation or flocculation) in solution followed by adsorption and (ii) surface aggregation (coagulation or flocculation). Surface aggregation appeared to be the most likely for pulp with a low degree of modification. The typical Langmuir adsorption isotherm correlated the data obtained for unmodified pulp very well.

Biogenic Jarosite: A Friendly Adsorbent for the Removal of Chromate from Aqueous Solution

2015 ◽  
Vol 737 ◽  
pp. 533-536 ◽  
Author(s):  
Dong Xue Xiao ◽  
Chang Ling Fang ◽  
Jun Zhou ◽  
Xiao Yi Lou ◽  
Jiu Hua Xiao ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Isotherm ◽  
Mine Drainage ◽  
Langmuir Adsorption Isotherm ◽  
Isotherm Models ◽  
Maximum Adsorption Capacity ◽  
Langmuir Adsorption ◽  
Adsorption Isotherm Models ◽  
Optimum Ph ◽  
Sulfate Leaching

Ferric hydrosulfate minerals are commonly byproducts of biotic oxidation of Fe (II) in acid mine drainage and biohydrometallurgy like biogenic jarosite. In this study, adsorption of Cr (VI) on jarosite was a rapid process and the optimum pH for Cr (VI) adsorption was found at 7.0. The variation of Cr (VI) adsorbed on jarosite fitted the Langmuir adsorption isotherm models and the maximum adsorption capacity was 3.23 mg/g. It was evident that anion exchange mechanism was responsible for Cr (VI) adsorption on jarosite based on the sulfate leaching data and optimum pH experiments.

scholarly journals SINTESIS MEMBRAN NATA DE PINA DAN APLIKASINYA UNTUK ADSORPSI ZAT WARNA TEKSTIL REMAZOL RED RB

Jurnal Kimia ◽  
2020 ◽  
pp. 134
Author(s):  
I N. Sukarta
Keyword(s):  
Adsorption Isotherm ◽  
Contact Time ◽  
Absorption Capacity ◽  
Langmuir Adsorption Isotherm ◽  
Optimum Conditions ◽  
Langmuir Adsorption ◽  
Pineapple Peel ◽  
Optimum Ph ◽  
Remazol Red ◽  
Test Result

This study utilized pineapple peel waste into a membrane of nata de pina and used as an adsorbent for remazol red RB. The purpose of this study was to synthesis nata de pina membranes, determine the optimum pH, concentration and contact time of adsorption, isotherm pattern, and the maximum adsorption. The results indicated that cellulose nata de pina membranes were successfully synthesized and had the potential to become adsorbents for absorbing remazol red RB dyes. FTIR results showed that membrane nata de pina was a cellulose based membrane with swelling test result of 187.9%. The optimum conditions were at pH 2 with adsorption capacity of 17.12 mg/g, concentration of 80 mg/L with absorption capacity of 22.36 mg/g and contact time at 120 minutes with absorption capacity of 25.29 mg/g. The adsorption of remazol red RB dye has fulfilled the pattern of Langmuir adsorption isotherm with maximum adsorption of 0.0219 g/g or 21.9 mg/g adsorbent. Keywords: Adsorption, Nata de pina, membrane, Remazol red RB

Using iron-coated spent catalyst as an alternative adsorbent to remove Cr(VI) from water

1998 ◽  
Vol 38 (4-5) ◽  
pp. 155-162 ◽  
Author(s):  
J. C. Liu ◽  
J. G. Huang
Keyword(s):  
Aqueous Solution ◽  
Adsorption Isotherm ◽  
Langmuir Adsorption Isotherm ◽  
Iron Salt ◽  
Spent Catalyst ◽  
Potential Measurement ◽  
Sulfate Ions ◽  
Langmuir Adsorption ◽  
Removal Capacity ◽  
Iron Coating

The feasibility of utilizing iron-coated spent catalyst to adsorb Cr(VI) from aqueous solution was studied. Various factors, such as types and concentrations of iron salt, pH, and initial Cr(VI) concentration were investigated. A significant increase in Cr(VI) removal capacity can be achieved through iron-coating. The maximum adsorption was found at pH of 3.0-4.0. The presence of chloride and sulfate ions were found to suppress Cr(VI) adsorption. Langmuir adsorption isotherm was utilized to describe the adsorption reaction. Results from zeta potential measurement indicate that Cr(VI) is adsorbed largely through electrostatic interaction onto iron-coated spent catalyst. This study shows that spent catalyst can be converted to a useful adsorbent for Cr(VI) removal.

scholarly journals Diffusion of calcium ions in retinal rods. A theoretical calculation.

1981 ◽  
Vol 77 (4) ◽  
pp. 475-487 ◽  
Author(s):  
S McLaughlin ◽  
J Brown
Keyword(s):  
Diffusion Coefficient ◽  
Adsorption Isotherm ◽  
Calcium Ions ◽  
Outer Segment ◽  
Effective Diffusion ◽  
Langmuir Adsorption Isotherm ◽  
Diffuse Double Layer ◽  
Langmuir Adsorption ◽  
Retinal Rods ◽  
Disk Membrane

The Fick diffusion equation is combined with the Langmuir adsorption isotherm and the relevant equations from the Gouy-Chapman theory of the electrical diffuse double layer to demonstrate that the effective diffusion coefficient of calcium ions, both in the cytoplasm of the rod outer segment and within the aqueous space bounded by the disk membrane, should be reduced by a factor of 10-100 because these ions adsorb to phospholipids present in the disk membrane.

A further note on the measurement of the affinity of a dye (Azure A) for histological substrates

1965 ◽  
Vol s3-106 (76) ◽  
pp. 299-306
Author(s):  
D. J. GOLDSTEIN
Keyword(s):  
Adsorption Isotherm ◽  
Goblet Cell ◽  
Binding Sites ◽  
Langmuir Isotherm ◽  
Langmuir Adsorption Isotherm ◽  
Intestinal Epithelial ◽  
Langmuir Adsorption ◽  
Azure A ◽  
First Approximation ◽  
The Ideal

If two histological sections, of thickness nµ and 2nµ, and having the same apparent intensity of staining, are at equilibrium with dyebaths of concentration B1 and B2 respectively, the affinity of the histological substrate for the dye is, under denned conditions, given by the expression ΔF° = - RT In I/B, where B is either (i) B2 if the thinner section is stained to saturation, or (ii) B1 if B1 = 3B2. The affinity tends to be greater when measured in a weaker dyebath, as implied in method (ii). Evidence is presented suggesting that the uptake of the basic dye Azure A by pancreatic basal chromidial substance, goblet cell mucin and intestinal epithelial cytoplasm follows a Langmuir adsorption isotherm to a first approximation, in that, at low dyebath concentrations, the uptake of dye is proportional to the concentration of dyebath with which the substrate is in equilibrium, while in strong dyebaths the uptake approaches a plateau. A deviation from the ideal Langmuir isotherm in dyebaths of moderate concentration, observed in epithelial cytoplasm and to a lesser extent in pancreatic basal chromidial substance, may have been due to interaction between neighbouring dye-binding sites, or to the presence in a single area of sites with different affinities for the dye.

THE SORPTION OF ACIDS BY WOOL

1949 ◽  
Vol 27b (12) ◽  
pp. 879-889 ◽  
Author(s):  
R. Donovan ◽  
P. Larose
Keyword(s):  
Hydrochloric Acid ◽  
Adsorption Isotherm ◽  
Sulphuric Acid ◽  
Sodium Sulphate ◽  
Langmuir Adsorption Isotherm ◽  
Langmuir Equation ◽  
Recent Application ◽  
Satisfactory Explanation ◽  
Isotherm Equation ◽  
Langmuir Adsorption

The amount of acid sorbed by wool from solutions of sulphuric acid of four different strengths (namely, 0.0505, 0.0339, 0.0182, and 0.0101 molar) and containing sodium sulphate in amounts varying up to 0.16 molar has been determined. It has been found that the presence of the salt has little effect on the quantity of acid sorbed within those limits. The results are analyzed in the light of the theory of Gilbert and Rideal but this theory fails to give a satisfactory explanation of the results obtained. It is possible, however, to explain the results of the authors' experiments on the basis of the recent application of the Donnan equilibrium by Peters and Speakman. The Langmuir adsorption isotherm equation has been applied to data on the absorption of hydrochloric acid and of sulphuric acid by wool. The data appear to fit the Langmuir equation and give, for the maximum combining capacity, values that agree well with those estimated in other ways.

Adsorption Characteristic Research of Sediments of Lake Baiyangdian

2014 ◽  
Vol 511-512 ◽  
pp. 55-58
Author(s):  
Zhe Qin ◽  
Qian Wang ◽  
Zheng Liu
Keyword(s):  
Adsorption Isotherm ◽  
Nitrogen Adsorption ◽  
Ammonia Nitrogen ◽  
Langmuir Adsorption Isotherm ◽  
Adsorption Characteristic ◽  
Langmuir Adsorption ◽  
Lake Baiyangdian ◽  
Object Of Study ◽  
Total Maximum ◽  
Adsorption Quantity

This paper regarded the sediments of Lake Baiyangdian as the object of study, researched and analyzed ammonia nitrogen adsorption characteristics of sediment samples. The results showed that: the sediments adsorption to ammonia nitrogen reached a state of equilibrium after 2.5h, The ammonia nitrogen adsorption rate was maximum in 0~10min. Sediment adsorption of ammonia nitrogen was higher as ammonia nitrogen liquid balance concentration increased. The adsorption isotherm curve of ammonia nitreogen can be fitted well by the Langmuir adsorption isotherm model. The total maximum adsorption quantity of ammonia nitrogen by the sediments of Lake Baiyangdian is between 54.12mg/kg to 240.12mg/kg.

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