Formulae Relating N and J to the Different Separation Factors Q

1970 ◽  
pp. 28-47
Author(s):  
STANLEY HARTLAND
Keyword(s):  
Separation Factors

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.

Europium and cerium extraction by the nitrobenzene solution of dicarbolide in the presence of polyethylene glycols

1986 ◽  
Vol 51 (3) ◽  
pp. 498-515 ◽  
Author(s):  
Emanuel Makrlík ◽  
Petr Vaňura
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Equilibrium Constants ◽  
Polyethylene Glycols ◽  
Individual Species ◽  
Nitrobenzene Solution ◽  
Separation Factors ◽  
Equilibrium Data

Extraction of Eu3+ and Ce3+ microamounts from 0.1-0.4M perchloric acid by the nitrobenzene solution of dicarbolide H+[Co(C2B9H11)2]- in the presence of polyethylene glycols (Mr = 200, 300, 400) has been studied. The equilibrium data and the typical maxima on the dependence of the metal distribution ratio on the total analytical concentration of polyethylene glycol in the system can be explained assuming that the species ML3+org, ML3+2org, ML3+3org, MLH2+-1org, and HL+org (where M3+ = Eu3+, Ce3+; L = polyethylene glycol) are extracted into the organic phase. The values of extraction and equilibrium constants in the organic phase were determined and the effect of the polyethylene glycol molecular weight on the equilibrium constants and on the abundances of individual species in the organic phase is discussed. It has been found that the addition of polyethylene glycol to the acid - nitrobezene - dicarbolide system increases the values of the separation factors αCe/Eu.

Extraction of Am(III) by benzyldibutylamine from nitrate solutions of lanthanides

1981 ◽  
Vol 46 (1) ◽  
pp. 194-200 ◽  
Author(s):  
Marta Vojtíšková ◽  
Věra Jedináková ◽  
Libor Kuča
Keyword(s):  
Nitric Acid ◽  
Nuclear Fuel ◽  
Organic Phase ◽  
Spent Nuclear Fuel ◽  
Optimum Conditions ◽  
Separation Factors ◽  
Nitrate Solutions

Benzyldibutylamine is a suitable extractant for the separation of Am(III) and Ln(III) from the acidic nitrate solutions. The effect of lanthanides and yttrium on the extraction of Am(III) has been followed under the conditions modelling the content of these components in the spent nuclear fuel. The separation factors αAm/Ln were evaluated for the optimum conditions found for the separation of Am(III) from the lanthanides. The coextraction of nitric acid and water into the organic phase is discussed.

scholarly journals Adsorption Properties of Modified Clinoptilolite for Methane and Nitrogen

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2024 ◽  
Author(s):  
Xiaofei Hao ◽  
Hongjie Hu ◽  
Zhen Li ◽  
Limei Wu ◽  
Xueqin Liu ◽  
...  
Keyword(s):  
Coalbed Methane ◽  
Pressure Swing Adsorption ◽  
Adsorption Properties ◽  
Unconventional Gas ◽  
Mixture Separation ◽  
Separation Factors ◽  
Methane Mixture ◽  
Equilibrium Separation ◽  
Pressure Swing ◽  
Modified Clinoptilolite

Coalbed methane (CBM) is a kind of unconventional gas. CBM often contains a great deal of air when it comes out of the well. So, it must be condensed and purified before it can be applied. In this paper, raw clinoptilolite (Cp) was treated with grinding, gravimetric concentration, and ion-exchange using different aqueous solutions of salts. Then, the modified Cp powder was prepared into particles as adsorbents. Then, the adsorbents were used for nitrogen/methane separation in pressure swing adsorption (PSA) at the same condition of 0.2 MPa and 298 K. Research results indicated that there were micropores and lots of mesopores in the Cp, and the pores were mainly slit holes formed by sheet stacking. The adsorbents of NH4-Cp, Cs-Cp, and Cu-Cp showed good equilibrium selectivity for CH4, and the equilibrium separation factors of CH4 and N2 were 2.56, 2.31, and 1.95, respectively. The adsorbents of Na-Cp and Ag-Cp showed good equilibrium selectivity for N2, and the equilibrium separation factors of N2 and CH4 were 7.25 and 6.53, respectively. Consequently, the adsorbent of Na-Cp was suitable for nitrogen/methane mixture separation, which could make the concentration of methane concentrated from 19.7% to 30.72%.

scholarly journals Separating Hydrogen From Coal Gasification Gases With Alumina Membranes

1991 ◽  
Author(s):  
B. Z. Egan ◽  
D. E. Fain ◽  
G. E. Roettger ◽  
D. E. White
Keyword(s):  
Carbon Dioxide ◽  
Coal Gasification ◽  
Process Development ◽  
Porous Alumina ◽  
Mean Value ◽  
Knudsen Flow ◽  
Gasification Process ◽  
Alumina Membranes ◽  
Separation Factors ◽  
Membrane Permeabilities

Synthesis gas produced in coal gasification processes contains hydrogen, along with carbon monoxide, carbon dioxide, hydrogen sulfide, water, nitrogen, and other gases, depending on the particular gasification process. Development of membrane technology to separate the hydrogen from the raw gas at the high operating temperatures and pressures near exit gas conditions would improve the efficiency of the process. Tubular porous alumina membranes with mean pore radii ranging from about 9 to 22 A have been fabricated and characterized. Based on the results of hydrostatic tests, the burst strength of the membranes ranged from 800 to 1600 psig, with a mean value of about 1300 psig. These membranes were evaluated for separating hydrogen and other gases. Tests of membrane permeabilities were made with helium, nitrogen, and carbon dioxide. Measurements were made at room temperature in the pressure range of 15 to 589 psi. In general, the relative gas permeabilities correlated qualitatively with a Knudsen flow mechanism; however, other gas transport mechanisms such as surface adsorption may also be involved. Efforts are under way to fabricate membranes having still smaller pores. At smaller pore sizes, higher separation factors are expected from molecular sieving effects.

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