Pyrrhotite equilibrium line, pyrite

Iso-FeS content lines for sphalerite in equilibrium with pyrite or pyrrhotite were drawn on the log/sj-temperature diagram (Figs. 1.179 and 1.180) using thermochemical data by Scott and Bames (1971) and Barton and Skinner (1979). 

Figure 3.7 Electrochemical phase diagram for sodium sulphide with elemental sulphur as metastable phase. Equilibrium lines (solid lines) correspond to dissolved species at 10" mol/L. Plotted points show the upper and lower limit potential of sulphur-included flotation of pyrite, pyrrhotite and arsenopyrite from literature...

Note that the equilibrium line for pyrite and pyrrhotite falls across... 

Barton equilibrium line, or fall on the pyrite-pyrrhotite line of the phase diagrams. The coals with higher intrinsic pyrite content or those to which pyrite or iron-containing materials were added have pyrrhotites which fall nearer the reactor zone. 

Figure 1.96. Log /oj-pH diagram constructed for temperature = 200°C, ionic strength = 1, ES = 10 m, and EC = 10 m. Solid line represents aqueous sulfur and carbon species boundaries which are loci of equal molalities. Dashed lines represent the stability boundaries for some minerals. Ad adularia. Bn bomite, Cp chalcopyrite, Ht hematite, Ka kaolinite, Mt magnetite, Po pyrrhotite, Py pyrite, Se sericite. Heavy dashed lines (1), (2), and (3) are iso-activity lines for ZnCOs component in carbonate in equilibrium with sphalerite (1) 4 co3=0-1- (2) 4 ,co3=0-01- (3) 4 co3 =0-001 (Shikazono, 1977b).

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