Revised equilibrium data

Nordstrom, D.K., Ball, J.W. and McCleskey, R.B. (2003) Orpiment solubility equilibrium and arsenic speciation for a hot spring at Yellowstone National Park using revised thermodynamic data. Abstracts with Programs. The Geological Society of America, 35(6), 47. 

D. K. Nordstrom et al., Revised chemical equilibrium data for major water-mineral reactions and their limitations, Chap. 31 in D. C. Melchior and R. L. Bassett, op. cit.27... 

Phase-Equilibrium Data Shaw, D. G., and A. Maczynski (eds.), IUPAC Solubility Data Series, Vol. 81 Hydrocarbons in Water and Seawater—Revised and Updated, published in 12 parts in /. Fhys. Chem. Ref. Data, 2005 and 2006 Gmehling, J., et al, Vapor-Liquid Equilibrium Data Collection Aqueous-Organic Systems, DECHEMA Chemistry Data Series, Vol. I, Part 1-ld, Schon Wetzel GmbH, Frankfurt/Main, Germany, 1988. 

Equilibrium log values calculated from free energy data (41) for two lead hydroxychiorides (PbOHCl, Pb2(OH)3Cl) did not agree with those of the original authors (57). However, revised AG data (10) from NBS (B. R. Staples, Nat l Bur. Stand., personal... 

Nordstrom D. K., Plummer L. N., Langmuir D., Busenberg E., May H. M., Jones B. F., and Parkhurst D. L. (1990) Revised chemical equilibrium data for major water-mineral reactions and their limitations. In Chemical Modelling of Aqueous Systems II, Symp. Ser. 416 (eds. D. C. Melchior and R. L. Bassett). American Chemical Society, Washington, DC, pp. 398-413. 

APPENDIX 1 REVISED CHEMICAL EQUILIBRIUM DATA FOR MAJOR WATER-MINERAL REACTIONS ... 

The selected A H"(298.15 K) is a weighted average of a revised calorimetric determination and a 3rd law calculation using equilibrium data. 

Revised Chemical Equilibrium Data for Major Water—Mineral Reactions and Their Limitations... 

It Is the intention of the authors to publish more complete and accurate revisions of these tables as demanded by the continually growing body of equilibrium data in the literature. 

Baddour and Blanchet (I) paid particular attention to the possible existence of C2H, C3H, C4H, CH, and CH2 in the equilibrium mixture. They assumed that at temperatures above 3000°K. the equilibrium mixture contained the following species Ci, C2, C3, H, H2, C2H2, C2H, C3H, C4H, C4H2, CH, and CH2, the last two becoming significant above 4000°K. Values of the free energy functions and the equilibrium constants for the 16 reactions were calculated by Blanchet by the method of Bauer and Duff (2). The calculated values necessarily depend upon the values assumed for the heat of formation and may require revision for certain species as new data become available. 

The mass-action equations have been written in the same form as those given by Marynowski et al. (6) so that the equilibrium constants can be used directly. (Should more accurate data become available, the equilibrium yields calculated here will require revision.) The fourth equation, which applies to the heterogeneous equilibrium between carbon and nitrogen, is included for completeness but is unnecessary for the general solution. It can be shown that when the total pressure of the system is F, the partial pressure of cyanogen radicals is given by the equation ... 

Techniques for hydrate inhibition deal with the methanol concentration in the aqueous liquid in equilibrium with hydrate at a given temperature and pressure. The user also must determine the amount of methanol to be injected in the vapor. This problem was addressed first by Jacoby (1953) and then by Nielsen and Bucklin (1983), who presented a revised methanol injection calculation. The most recent data are by Ng and Chen (1995) for distribution of methanol in three phases (1) the vapor phase, (2) the aqueous phase, and (3) the liquid hydrocarbon phase. 

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