A New Reference State for the Calculation of Activity Coefficients: Comment on the Paper “Molecular Theory of the Activity Coefficient and Their Reference Fugacities at the Supercritical State”

In this paper, we jointly use the Pitzer model and the Meissner model to study thermodynamic laws of bioleaching solution in a lean nickel-cobalt ore in the Jilin Baishan, by using the Pitzer model to calculate activity coefficients of single electrolyte aqueous solutions and the Meissner model to calculate activity coefficients of components in the bioleaching solution. Also we studied the rules of activity coefficient of NiSO4 and CoSO4 in the solution. Results show that when separating and purifying foreign ions from bioleaching solution of the lean nickel-cobalt ore, the descending sequence of their ion concentration’s effect over the solution is Mg2+, Fe3+, Fe2+, Ni2+, Co2+ and Ca2+.

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Flash point of organic binary mixtures containing alcohols: experiment and prediction

Open Chemistry ◽

10.2478/s11532-012-0171-6 ◽

2013 ◽

Vol 11 (3) ◽

pp. 388-393 ◽

Cited By ~ 4

Author(s):

Mariana Hristova ◽

Dimitar Damgaliev

Keyword(s):

Experimental Data ◽

Activity Coefficient ◽

Binary Mixtures ◽

Activity Coefficients ◽

Thermodynamic Model ◽

Flash Point ◽

Wilson Equation ◽

Nrtl Equation

AbstractThe flash points of three organic binary mixtures containing alcohols were measured in the present work. The experimental data was obtained using the Pensky-Martens closed cup tester. The experimental data were compared with the values calculated by the Liaw model. Activity coefficients were calculated by the Wilson equation and NRTL equation. The accuracy of predicted flash point values is dependent on the thermodynamic model used for activity coefficient.

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The thermodynamic properties of sulphonated polystyrene exchanges saturated with a single cation

Australian Journal of Chemistry ◽

10.1071/ch9550293 ◽

1955 ◽

Vol 8 (3) ◽

pp. 293 ◽

Cited By ~ 5

Author(s):

JF Duncan

Keyword(s):

Experimental Data ◽

Activity Coefficient ◽

Activity Coefficients ◽

Hydrogen Exchange ◽

Aqueous Electrolyte ◽

Aqueous Electrolytes ◽

Sodium Potassium ◽

Resin Phase ◽

Sodium Hydrogen ◽

Independent Experimental Data

If an ion exchanger is treated as if it were an aqueous electrolyte, it is possible to use several independent experimental data to calculate the osmotic and activity coefficients of the resin phase. Illustrative examples are quoted. The activity coefficient of pure sodium " resinate " is calculated with satisfactory agreement from isopiestic data, and by two methods from the sodium-hydrogen exchange reaction. Activity coefficient curves for lithium, sodium, potassium, rubidium, caesium, copper, and barium " resinates " are given and also activity coefficient data for a number of other divalent cationic " resinates ", at a single value of the ionic strength. These activity coefficients show similar trends to those of aqueous electrolytes.

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Oxygen exchange in methanol in acid solutions. Transition state activity coefficients

Canadian Journal of Chemistry ◽

10.1139/v80-063 ◽

1980 ◽

Vol 58 (4) ◽

pp. 393-398 ◽

Cited By ~ 2

Author(s):

Robert A. McClelland

Keyword(s):

Sulfuric Acid ◽

Activity Coefficient ◽

Transition State ◽

Activity Coefficients ◽

Oxygen Exchange ◽

Acid Solutions ◽

Salting Out ◽

Carbonium Ion ◽

State Activity ◽

Significant Difference

Rate constants for oxygen exchange of methanol in sulfuric acid and perchloric acid solutions are reported, along with activity coefficients of methanol in sulfuric acid. Transition state activity coefficients (f≠*) for methanol exchange and tert-butanol exchange have been calculated. Values of f≠* for the latter behave very similarly to those for tert-butyl acetate hydrolysis, consistent with a carbonium ion-like transition state. Values for methanol exchange show considerably more salting-out, consistent with an oxonium ion-like transition state. A significant difference with the AAc2 hydrolyses of esters and amides is noted. For the latter the transition state is salted-out relative to its protonated precursor, whereas for methanol exchange, there is little difference between the activity coefficient of the protonated alcohol and the transition state, with the latter actually being somewhat salted-in. It is pointed out that the transition state activity coefficient approach can be rigorously applied even in the absence of protonation data.

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Method for Estimating Activity Coefficients of Target Components in Poorly Specified Mixtures

10.31219/osf.io/6mpfd ◽

2021 ◽

Author(s):

Fabian Jirasek ◽

Jakob Burger ◽

Hans Hasse

Keyword(s):

Nmr Spectroscopy ◽

Activity Coefficient ◽

Activity Coefficients ◽

New Method ◽

Target Component ◽

Test Cases ◽

Group Contribution Method ◽

Bioprocess Engineering ◽

Separation Processes ◽

Chemical Groups

Mixtures that contain a known target component but are otherwise poorly specified 15 are important in many fields. Previously, the activity of the target component, which is needed e.g. to design separation processes, could not be predicted in such mixtures. A method was developed to solve this problem. It combines a thermodynamic group contribution method for the activity coefficient with NMR spectroscopy, which is used for estimating the nature and amount of the different chemical groups in the mixture. The knowledge of the component 20 speciation of the mixture is not required. Test cases that are inspired by bioprocess engineering applications show that the new method gives surprisingly good results.

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Solubility of thallium pertechnate in nitrate solutions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19813083 ◽

1981 ◽

Vol 46 (12) ◽

pp. 3083-3087 ◽

Cited By ~ 1

Author(s):

Vladimír Mikulaj ◽

Eva Mišianiková ◽

Fedor Macášek

Keyword(s):

Activity Coefficient ◽

Aqueous Solutions ◽

Activity Coefficients ◽

Molar Activity ◽

Nitrate Solutions

Solubility of TlTcO4 was determined in water and in HNO3, NaNO3, NH4NO3, Ca(NO3)2, and LiNO3 aqueous solutions in concentrations 5-8 mol l-1. The solubility increases with increasing concentration of the electrolyte; the values measured were used for a calculation of the stoichiometric molar activity coefficients of the Tl+ and TcO4- ions. The activity coefficient values corrected for the fraction of the nonassociated Tl+ ions approach those of the base electrolytes up to their concentrations of 4-5 mol l-1.

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Physical Interpretation of Solubility Interaction Constants from the Series Expansion of the Relative Activity Coefficients

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941911 ◽

1994 ◽

Vol 59 (9) ◽

pp. 1911-1921 ◽

Cited By ~ 5

Author(s):

Jaroslav Nývlt ◽

Jitka Eysseltová

Keyword(s):

Activity Coefficient ◽

Series Expansion ◽

Activity Coefficients ◽

Physical Interpretation ◽

Ternary Systems ◽

Relative Activity ◽

Solubility Data ◽

Close Relationship ◽

Insight Into ◽

Saturated Solutions

Hydration analysis, which enables information on ionic processes in saturated solutions to be derived from solubility data in ternary systems, was applied to the interpretation of solubility interaction constants from the relative activity coefficient expansion. A close relationship was found between the hydration analysis parameters and the solubility interaction constants characterizing the relative activity of solute, which extends our insight into the ionic behaviour of the system studied by using the values of the interaction constants.

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