Kinetics of partition between aqueous solutions of salts and bulk liquid membranes containing neutral carriers

A new kinetic synergism system for copper(II) transport through a bulk liquid membrane containing mono(2-ethyhexyl)-2-ethyhexyl phosphate and Manoxol OT (OT) was examined. The influence of stripping agent, anion, pH in feed phase, and carrier concentration were investigated. The kinetics of Cu(II) transport could be analyzed in the formalism of two consecutive irreversible first-order reactions, considering both extraction and stripping. The pseudo-first-order apparent rate constants of interfacial reactions in membrane transport are determined by altering the temperature. The activation energy values are 38.1 kJ mol1 for extraction and 32.8 kJ mol1 for stripping. The experiments demonstrated that Manoxol OT is a good kinetic synergist for Cu(II) transport through liquid membranes in this study. The kinetic synergism of OT for extraction of Cu2+ ions is analyzed.Key words: copper ions, kinetic synergist, liquid membrane.

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Effects of salts on the kinetics of oxidation of alkenes by thallic salts in aqueous solutions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19810693 ◽

1981 ◽

Vol 46 (3) ◽

pp. 693-700 ◽

Cited By ~ 1

Author(s):

Milan Strašák ◽

Jaroslav Majer

Keyword(s):

Aqueous Solutions ◽

Phase Transfer ◽

Heterogeneous Reaction ◽

Qualitative Model ◽

Kinetic Effect ◽

Tetraalkylammonium Salts ◽

Reaction Conditions ◽

Kinetics Of Oxidation ◽

Kinetics Of ◽

Heterogeneous Reaction Conditions

The kinetics of oxidation of alkenes by thallic sulphate in aqueous solutions, involving the two reaction steps-the hydroxythallation and the dethallation - was studied, and the effect of salts on the kinetics was examined; this made it possible to specify more precisely the reaction mechanism and to suggest a qualitative model of the reaction coordinate. It was found that in homogeneous as well as in heterogeneous reaction conditions, the reaction can be accelerated appreciably by adding tetraalkylammonium salts. These salts not only operate as catalysts of the phase transfer, but also exert a significant kinetic effect, which can be explained with a simplification in terms of a stabilization of the transition state of the reaction.

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Preparation and Evaluation of Skeletal Cobalt-Molybdenum Hydrodesulfurization Catalysts

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950568 ◽

1995 ◽

Vol 60 (4) ◽

pp. 568-575

Author(s):

Karel Sporka ◽

Jiří Hanika ◽

Vladimír Jůn

Keyword(s):

Aqueous Solutions ◽

Active Component ◽

Catalyst Activity ◽

Gas Oil ◽

Gamma Alumina ◽

Molybdenum Sulfides ◽

Hydrodesulfurization Catalysts ◽

Hds Catalysts ◽

Kinetics Of ◽

Preparation And Evaluation

Preparation of skeletal Co-Mo catalysts by controlled impregnation of aluminosilicate skeletons containing deposited gamma-alumina with aqueous solutions of active component precursors has been investigated. The activity of the laboratory catalysts in gas oil hydrodesulfurization has been determined. Kinetics of impregnation of skeletal supports, the effect of their type, and the dependence of catalyst activity on the content of cobalt and molybdenum sulfides are reported. HDS skeletal catalysts prepared were compared with the extruded types. It was found that skeletal HDS catalysts show the higher activity (related to the content of alumina and Co-Mo sulfides) than the extruded ones due to the less significant effect of internal diffusion. However, if the activity is related to the same volume of catalyst bed, the activity of skeletal catalysts is only one fourth of that of the extruded types.

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Study of potential oscillations during reaction of an aluminium single crystal with an aqueous KOH solution

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19900345 ◽

1990 ◽

Vol 55 (2) ◽

pp. 345-353 ◽

Cited By ~ 4

Author(s):

Ivan Halaša ◽

Milica Miadoková

Keyword(s):

Aqueous Solutions ◽

Single Crystal ◽

Single Crystals ◽

Periodic Potential ◽

Optimum Conditions ◽

Potential Oscillations ◽

Dilute Aqueous Solutions ◽

Experimental Findings ◽

Kinetics Of

The authors investigated periodic potential changes measured on oriented sections of Al single crystals during spontaneous dissolution in dilute aqueous solutions of KOH, with the aim to find optimum conditions for the formation of potential oscillations. It was found that this phenomenon is related with the kinetics of the reaction investigated, whose rate also changed periodically. The mechanism of the oscillations is discussed in view of the experimental findings.

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Penetration Dynamics of Solid Particles into Liquids High-Speed Experimental Results and Modelling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.473-474.429 ◽

2005 ◽

Vol 473-474 ◽

pp. 429-434 ◽

Cited By ~ 9

Author(s):

Olga Verezub ◽

György Kaptay ◽

Tomiharu Matsushita ◽

Kusuhiro Mukai

Keyword(s):

Contact Angle ◽

Particle Size ◽

Aqueous Solutions ◽

Particle Velocity ◽

Weber Number ◽

High Speed ◽

Solid Particles ◽

Bulk Liquid ◽

Distilled Water ◽

Critical Weber Number

Penetration of model solid particles (polymer, teflon, nylon, alumina) into transparent model liquids (distilled water and aqueous solutions of KI) were recorded by a high speed (500 frames per second) camera, while the particles were dropped from different heights vertically on the still surface of the liquids. In all cases a cavity has been found to form behind the solid particle, penetrating into the liquid. For each particle/liquid combination the critical dropping height has been measured, above which the particle was able to penetrate into the bulk liquid. Based on this, the critical impact particle velocity, and also the critical Weber number of penetration have been established. The critical Weber number of penetration was modelled as a function of the contact angle, particle size and the ratio of the density of solid particles to the density of the liquid.

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