Study of the ZnSO4-Cyanex 302 extraction equilibrium system

1991 ◽  
Vol 27 (3) ◽  
pp. 327-338 ◽  
Author(s):  
C. Caravaca ◽  
F.J. Alguacil
Keyword(s):  
Equilibrium System ◽  
Extraction Equilibrium ◽  
Cyanex 302

Study of the KAu (CN)2-amine amberlite LA-2 extraction equilibrium system

1990 ◽  
Vol 24 (2) ◽  
pp. 157-166 ◽  
Author(s):  
F.J. Alguacil ◽  
A. Hernandez ◽  
A. Luis
Keyword(s):  
Equilibrium System ◽  
Extraction Equilibrium

scholarly journals Cyanex 302: An extractant for Fe3+ from Chloride Medium

1970 ◽  
Vol 46 (4) ◽  
pp. 407-414 ◽  
Author(s):  
MR Ali ◽  
RK Biswas ◽  
SMA Salam ◽  
A Akhter ◽  
AK Karmakar ◽  
...  
Keyword(s):  
Aqueous Phase ◽  
Equilibration Time ◽  
Extractant Concentration ◽  
Phase Contact Time ◽  
Extraction Equilibrium ◽  
Cyanex 302 ◽  
Wide Range ◽  
Aqueous Chloride ◽  
Parallel Reactions ◽  
Aqueous Acidity

The solvent extraction of Fe3+ from aqueous chloride solution by bis-(2,4,4-trimethylpentyl) monothiophosphinic acid (Cyanex 302, H2A2) dissolved in kerosene has been investigated over a wide range of aqueous acidity as a function of phase contact time, concentrations of Fe3+, H+ and Cl- in the aqueous phase, Cyanex 302 concentration in the organic phase and temperature. The equilibration time is 50 min. The distribution ratio is found to be independent on [Fe3+] in the aqueous phase at a constant aqueous acidity and extractant concentration. The H+, extractant and Cl- dependences are -1, 0.5 in low concentration region of extractant and -0.5, respectively; which suggest that extraction occurs via the following two parallel reactions: (i) FeCl3 + 0.5 H2A2(o) FeCl2.A(o) + H+ + Cl-; and (ii) FeCl2 + + 0.5 H2A2(o) -----FeCl2A(o) + H+. Temperature dependence data give ΔH value of 9.95 kJ/ mol. The loading capacity of Cyanex 302 towards Fe3+ is 29.41 g Fe3+/100 g Cyanex 302. The extraction equilibrium constant (Kex) is 10-0.632. Extraction ratio is found to be dependent on diluent used. Stripping of the extracted complex is found to be a difficult task, but may be made effective by a solution containing 6 M H2SO4 and 1 M Na2C2O4. Keywords: Extraction equilibrium; Fe3+ extraction; Cyanex 302; Chloride medium.DOI: http://dx.doi.org/10.3329/bjsir.v46i4.9583 BJSIR 2011; 46(4): 407-414

KINEMATIC FEATURES OF THE LAPPING PROCESS AND DETERMINATION OF ITS BASIC PARAMETERS

2020 ◽  
Vol 7 (3) ◽  
pp. 23-28
Author(s):  
EZIZ SARVAN SHIRVAN ◽  
Keyword(s):  
Dynamic Properties ◽  
Cutting Speed ◽  
Equilibrium System ◽  
Technological Parameters ◽  
Kinematic Characteristics ◽  
Angular Velocities ◽  
Basic Parameters ◽  
Grinding Tool ◽  
Mathematical Relationships ◽  
Analytical Expressions

This paper discusses the kinematic characteristics of lapping process and the main parameters of the process. It was determined that the influencing degree of technological parameters to the forming surface and processes. It was projected the construction of the lapping head for processing of internal cylindrical surfaces, scheme of the lapping operation and graphic description of the forces influencing. The relationships between the axial, radial and tangential cutting forces and the effect of the combined force thereof are determined in order to ensure the necessary surface pressure. During the analysis geometric and mathematical relationships were obtained. The extracted analytical expressions can be realized by further experimental researches and can be used in engineering calculations of technological parameters of processing by lapping. Angular velocity, friction force, linear velocity, also the length of the tactile curve and the radius of the part can be considered the main kinematic and dynamic parameters of the process that the formation of the surface, also the course of the process depends on these parameters. Depending on the kinematic parameters, the wear nature of the tool changes and this changes the linear and angular velocities, which have a significant impact on the accuracy, quality and productivity of processing. When examining the technological capabilities of the process, the nature of the movement between the part and the grinding tool, also changes in cutting speed are often considered as a main factor. Analytical expressions were obtained to determine the main parameters of the process, taking into account the kinematic characteristics of the friction process. These expressions can be used in engineering calculations and allow to determine the optimal values of the processing mode. In order to obtain the required micrometric surface cleanliness and measurement accuracy, correlation relationships were established between the main parameters of the process, equations of the equilibrium system of shear forces were compiled and analytical expressions were obtained based on the analysis of kinematic and dynamic properties of the system.

Efficient trace-scale extraction method of reactor produced 199Au adequate for nuclear medicine applications

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed F. Attallah ◽  
Ahmed M. Shahr El-Din ◽  
Mohamed A. Gizawy ◽  
Amal M. I. Ali
Keyword(s):  
Aqueous Media ◽  
Selective Extraction ◽  
Extraction Process ◽  
High Yield ◽  
High Recovery ◽  
Rapid Separation ◽  
Efficient Separation ◽  
Liquid Liquid Extraction ◽  
Cyanex 302 ◽  
Cyanex 923

Abstract Production of no carrier-added (NCA) 199Au through natPt(n, γ) reaction and subsequent purification using liquid-liquid extraction from other radioisotopes is studied in the context of theranostic application. Comparative separation of NCA 199Au after dissolution of activated Pt target using three Cyanex compounds (Cyanex-272, Cyanex-302 and Cyanex-923) is evaluated. The extraction process is optimized in terms of the type of extractant, the concentration of extractant, extraction time and aqueous media (HNO3, NH4OH). Among these extractants, the Cynaex-923 is efficient and promising for rapid separation and production of NCA 199Au from HNO3 by high extraction %. Selective extraction of 199Au from other Pt and Ir radioisotopes is observed. High recovery of 199Au was obtained in the case of Cyanex-923 using 0.05 M thiourea dissolved in HCl or 2 M NaOH. Our results find the Cyanex-923 as a promising extractant for efficient separation of 199Au from irradiated Pt target with high yield (99%).

Synergetic formulation of Cyanex 272/Cyanex 302 for hexavalent chromium removal from electroplating wastewater

2021 ◽  
Vol 38 (3) ◽  
pp. 514-522
Author(s):  
Raja Norimie Raja Sulaiman ◽  
Norul Fatiha Mohd Noah ◽  
Norasikin Othman ◽  
Norela Jusoh ◽  
Muhammad Bukhari Rosly
Keyword(s):  
Hexavalent Chromium ◽  
Chromium Removal ◽  
Electroplating Wastewater ◽  
Cyanex 272 ◽  
Cyanex 302

scholarly journals Crystallization of Polymers under the Influence of an External Force Field

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2078
Author(s):  
Rajdeep Singh Payal ◽  
Jens-Uwe Sommer
Keyword(s):  
External Force ◽  
Melting Behavior ◽  
Mechanical Work ◽  
Stem Length ◽  
Heat Of Fusion ◽  
Strong Increase ◽  
Lamellar Thickness ◽  
Equilibrium System ◽  
External Force Field ◽  
Work Done

We simulated the crystallization and melting behavior of entangled polymer melts using molecular dynamics where each chain is subject to a force dipole acting on its ends. This mimics the deformation of chains in a flow field but represents a well-defined equilibrium system in the melt state. Under weak extension within the linear response of the chains, the mechanical work done on the system is about two orders of magnitude smaller as compared with the heat of fusion. As a consequence, thermodynamic and simple arguments following the secondary nucleation model predict only small changes of the crystalline phase. By contrast, an increase of the stem length up to a factor of two is observed in our simulations. On the other hand, the lamellar thickening induced by the external force is proportional to the increase of the entanglement length in the melt prior to crystallization as measured by the primitive path method. While the mechanical work done on the system is only a small perturbation for thermodynamics of polymer crystallization, the change of the primitive path is large. This suggests that a strong increase in the lamellar thickness induced, by external deformation, a topological rather than a thermodynamic origin.

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