Anion-exchange Studies. XII.1,2Adsorption of Acids by Strong Base Anion-exchange Resins in Polyvalent Forms. Separation of Weak and Strong Acids

1955 ◽  
Vol 77 (2) ◽  
pp. 329-331 ◽  
Author(s):  
Frederick Nelson ◽  
Kurt A. Kraus
2017 ◽  
Vol 162 ◽  
pp. 19-26 ◽  
Author(s):  
E. Schoeman ◽  
S.M. Bradshaw ◽  
G. Akdogan ◽  
C.A. Snyders ◽  
J.J. Eksteen

2018 ◽  
Vol 20 (2) ◽  
pp. 368-372 ◽  

This study presents the evaluation of a strong base (Purolite A200) and weak base (Purolite PFA847) polymeric anion exchange resins for nitrite removal. The different parameters on the removal of NO2– were investigated in batch sorption mode. Common isotherm models; Langmuir and Freundlich, were used in order to present a description of the equilibrium data. Experimental results showed that the equilibrium data tend to follow Freundlich isotherm model for weak base resin and Langmuir model for strong base resin. The sorption of NO2– on anion exchange resins was found to follow the pseudo-second order kinetic model. The values of thermodynamic parameters proved that ion exchange reaction of NO2– onto such resins are endothermic (ΔH > 0).


1992 ◽  
Vol 17 (1) ◽  
pp. 15-20 ◽  
Author(s):  
E. Zaganiaris ◽  
S. Doulut ◽  
L. Morino

2012 ◽  
Vol 12 (5) ◽  
pp. 630-636 ◽  
Author(s):  
A. Phetrak ◽  
J. Lohwacharin ◽  
N. Watanabe ◽  
M. Murakami ◽  
H. Sakai ◽  
...  

Four strong-base anion exchange resins (AERs) with different properties were selected to investigate dissolved organic matter (DOM) removal from river water containing inorganic anions. Rapid sand-filtered water was obtained from a water treatment plant in Tokyo, Japan, and then concentrated by an ultrafiltration membrane for use in ion exchange experiments to simulate high dissolved organic carbon (DOC) and sulfate conditions. AERs removed 23–50% of DOC and 70–80% of UV254 within 30 min despite high sulfate concentration (121 mg/L). Although the materials and structure of the AERs did not affect the reduction of UV254, DOC removal was affected. The highest DOC reduction was achieved by a macroporous polyacrylic AER (Purolite), while the macroporous polystyrene IRA 910 had the lowest DOC removal. A pseudo-second-order kinetic model showed that the rate constants and the initial sorption rates of polyacrylic resins were higher than those by polystyrene resins, suggesting that more hydrophilic structure of AERs exhibited faster DOC removal. Aromatic DOM with a molecular weight (MW) of 800–3,000 Da was almost completely removed by AERs, whereas only half of aromatic DOMs smaller than 800 Da were removed by AERs. Adsorbed DOC comprised less than 6% of all exchanged anions, whereas the adsorbed sulfate was about 90% due to comparatively high concentration of sulfate in the water sample.


2014 ◽  
Vol 997 ◽  
pp. 363-367
Author(s):  
Guang Sheng Huo ◽  
Qiong Song ◽  
Chun Hua Liao

A solution containing tungsten and molybdenum was acidified using hydrochloric acid, and the ability of several commercial ion exchange resins to separate tungsten and molybdenum was evaluated. The results from the acidification test indicate that when the pH of the solution is adjusted to 7.0, WO42- is polymerized into HW6O215-, while MoO42- is not. The test results of resins selection show that the D213 resin and the D308 resin are superior to other resins in separating low concentrations of tungsten and molybdenum, whereas the D201 resin and the D309 resin are suitable for separating high concentrations of tungsten and molybdenum. The results from the column test indicate that weak-base anion exchange resins are better than strong-base anion exchange resins for both low and high concentrations of tungsten and molybdenum.


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