Caesium desorption from layer silicate minerals using quaternary ammonium salts

Clay Minerals ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 487-496 ◽  
Author(s):  
T. Miura ◽  
A. Sasaki ◽  
N. Suzuki ◽  
M. Endo

ABSTRACTThe adsorption and desorption of cesium onto layered minerals, zeolite and geochemical reference samples were studied. 0.5 g of bentonite and mica were able to adsorb 71.2 and 51.5 mg of cesium, respectively, from 50 mL of deionized water containing 200 mg/L of cesium under neutral pH condition. These amounts of cesium adsorption were greater than those reported for vermiculites (8.9 and 5.6 mg, respectively). Additionally, the cesium adsorption on mica and vermiculite remained essentially unchanged under seawater conditions, but it decreased drastically on zeolite. The cesium desorption from the layered minerals was promoted by the addition of ammonium ions, namely trioctylmethylammonium chloride and zephiramine. These ammonium ions desorb cesium from the interlayers of the minerals without destroying the mineral structure. The cesium desorption procedure using quaternary ammonium ions would be extremely useful for decontamination of soil containing the layered minerals with adsorbed radioactive cesium.

2014 ◽  
Vol 1030-1032 ◽  
pp. 90-94
Author(s):  
Zhong Xin Luo ◽  
Mang Lai Gao ◽  
Ya Ge Ye

To study the influence of layer charge and modifier on wettability plays an important role on the diagnosis of oil reservoir. In this paper, two quaternary ammonium salts (QASs) with different chain-length were used singularly or in compound form to modify the reduced-charge montmorillonites (RCMs). The wettability alterations of the organo-RCMs for deionized water and cyclohexane were studied based on capillary rise method. The results showed that RCMs singularly modified by QASs show different wettability characteristics. Moreover, there is a synergistic effect on the wettability when the RCMs are compound modified by two QASs and the organo-RCMs turn to more hydrophilic. The results of this work also indicated that it is possible to regulate the wettability of the RCMs by choosing different recipe of QASs, which is helpful to provide theoretical guidance for the oil production.


Author(s):  
Tomasz K. Olszewski ◽  
Anna Brol

An effective protocol for quaternization of simple 1-aminoalkylphosphonic acids under basic conditions and using Me2SO4 as convenient alkylating agent is reported. In the course of reaction phosphonic acid quaternary ammonium...


Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2424 ◽  
Author(s):  
Tăbăcaru ◽  
Botezatu ◽  
Horincar ◽  
Furdui ◽  
Dinică

A family of fifteen quaternary ammonium salts (QAs), bearing the 1,2-bis(4-pyridyl)ethane core, were obtained using for the first time two different green methods, such as microwave (MW) and ultrasounds (US) irradiation, with very good yields and in much shorter times compared to the classical method, and an assay on their antimicrobial action against Escherichia coli (E. coli) was carried out. While 12 to 24 hours were required for complete alkylation of 1,2-bis(4-pyridyl)ethane by reactive halogenated derivatives in anhydrous solvent under reflux conditions, MW and US irradiation reduced the reaction time and the desired products were achieved in a few min. One of the aims of this study was to evaluate the antibacterial potential of the synthesized QAs against pathogenic bacteria, along with their impact on germination activity of wheat seeds (Triticum aestivum L.). The antibacterial activity of the QAs against Escherichia coli was explored by determining the minimum inhibitory concentration (MIC). The MIC values varied from 0.312 to 2.5 mg/mL, highlighting the lowest values attained for the derivatives containing methoxy, chlorine and benzofurane functional groups. The viability of aerobic bacteria was determined with the Tetrazolium/Formazan Test, a method that was found to be the best alternative approach with respect to the difuzimetric method. Seeds of Triticum aestivum L. were used for the evaluation of the germination indicators, such as seed germination (SG), the relative seed germination (RSG), the relative radicle growth (RRG), and the seed germination index (GI). The toxicity studies of QAs 1, 4 and 7, at two different concentrations, showed no inhibitory effect on seed germination.


1996 ◽  
Vol 32 (6) ◽  
pp. 331-334
Author(s):  
V. V. Turov ◽  
O. A. Zaporozhets ◽  
O. Yu. Nadzhafova ◽  
V. V. Sukhan

Nature ◽  
1948 ◽  
Vol 161 (4097) ◽  
pp. 718-718 ◽  
Author(s):  
R. B. BARLOW ◽  
H. R. ING

Sign in / Sign up

Export Citation Format

Share Document