Solubility products of amorphous ferric arsenate and crystalline scorodite (FeAsO4 · 2H2O) and their application to arsenic behavior in buried mine tailings

Abstract Published solubility data for amorphous ferric arsenate and scorodite have been reevaluated using the geochemical code PHREEQC with a modified thermodynamic database for the arsenic species. Solubility product calculations have emphasized measurements obtained under conditions of congruent dissolution of ferric arsenate (pH

[1]  J. Jambor,et al.  The synthesis of crystalline scorodite, FeAsO4 · 2H2O , 1988 .

[2]  G. Demopoulos,et al.  Precipitation of crystalline scorodite (FeAsO4 · 2H2O) from chloride solutions , 1995 .

[3]  A. Monhemius,et al.  Hydrothermal precipitation from aqueous solutions containing iron(III), arsenate and sulphate , 1994 .

[4]  C. Baes,et al.  The hydrolysis of cations , 1986 .

[5]  P. G. Hill,et al.  A Fundamental Equation of State for Heavy Water , 1982 .

[6]  N. Welham,et al.  The stability of iron phases presently used for disposal from metallurgical systems—A review , 2000 .

[7]  J. D. Rnrsrtor.  The solubility and stability of scorodite, , 2007 .

[8]  David L. Parkhurst,et al.  USER'S GUIDE TO PHREEQC A COMPUTER PROGRAM FOR SPECIATION, REACTION-PATH, ADVECTIVE-TRANSPORT, AND INVERSE GEOCHEMICAL CALCULATIONS , 1995 .

[9]  G. Waychunas,et al.  Surface chemistry of ferrihydrite: Part 2. Kinetics of arsenate adsorption and coprecipitation , 1993 .

[10]  P. Brown,et al.  Unified theory of metal-ion-complex formation constants , 1987 .

[11]  G. Waychunas,et al.  Surface chemistry of ferrihydrite: Part 1. EXAFS studies of the geometry of coprecipitated and adsorbed arsenate , 1993 .

[12]  E. Virčíkova,et al.  Solubilities of amorphous FeAs precipitates , 1995 .

[13]  D. Kirk Nordstrom,et al.  Arsenic thermodynamic data and environmental geochemistry , 2003 .

[14]  J. Mahoney,et al.  Predicting arsenic concentrations in the porewaters of buried uranium mill tailings , 1999 .

[15]  K. G. Stollenwerk,et al.  Arsenic in ground water , 2003 .

[16]  G. A. Parks,et al.  Solubility and stability of scorodite, FeAsO4.2H2O: Discussion , 1987 .

[17]  D. L. Parkhurst,et al.  User's guide to PHREEQC (Version 2)-a computer program for speciation, batch-reaction, one-dimensional transport, and inverse geochemical calculations , 1999 .

[18]  J. Mahoney,et al.  Arsenic readily released to pore waters from buried mill tailings , 2005 .

[19]  D. Langmuir.  Aqueous Environmental Geochemistry , 1997 .

[20]  W. Hemminger.  Thermochemical data of pure substances, parts I and II : I. Barin, published by VCH, Weinheim, Germany, ISBN 3-527-27812-5, 1739 pages; DM 680 , 1993 .

[21]  D. Langmuir,et al.  Use of model-generated Fe3+ ion activities to compute Eh and ferric oxyhydroxide solubilities in anaerobic systems , 1990 .

[22]  V. Ettel,et al.  Solubility and stability of scorodite, FeAsO4•2H2O: new data and further discussion , 1988 .

[23]  A. Bard,et al.  Standard Potentials in Aqueous Solution , 1985 .

[24]  P. Dove,et al.  The solubility and stability of scorodite, FeAsO 4 .2H 2 O , 1985 .

[25]  Peiming Wang,et al.  A database and retrieval system for the NBS tables of chemical thermodynamic properties , 1989, J. Chem. Inf. Comput. Sci..

[26]  A. Townshend.  Standard potentials in aqueous solutions , 1987 .

[27]  G. A. Parks,et al.  Solubility and stability of scorodite, FeAsO 4 .2H 2 O; discussions and replies , 1987 .