Pyrite atmosphere with added

Figure 6. Demonstration of the increase in H2S evolution in an autogenous atmosphere with added pyrite...

Most of the sulfur in oil shale occurs in pyrite and a smaller amount is contained in the kerogen. The major source of H2S during oil shale pyrolysis appears to be the reaction of pyrite with organic matter. In an autogenous atmosphere, most of the H2S evolves between 400 and 500°C. Addition of finely ground pyrite increases the amount of H2S evolved but does not change the evolution profile. In an argon atmosphere, however, added pyrite causes a substantial increase in H2S evolution... 

The heap is covering an area of 100 100= 10.000 m2. Hence with a daily infiltration rate of 0.1 mm, 1000 liter of rainwater infiltrate every day. The volume of 0.1 m3 02 equals 100 liter 02 that are entering the heap each day by diffusion. Because one mol of gas equals 22.4 L gas at atmospheric pressure, 100 liter equal (100/22.4) 4.463 mol of 02. The PHREEQC job for the solution of this task is done as follows Distilled water (rainwater) is equilibrated with the C02- and (Impartial pressures of the atmosphere, then the extra oxygen from the diffusion into the heap is added by using REACTION and at last the resulting water is put into equilibrium with pyrite. 

Tetraphosphorus decasulphide, P4S10, was first prepared in 1843 by Berzelius [22]. It can be made by direct reaction of the elanents under an atmosphere of CO2. An alternative method is to heat iron phosphide (or ferrophosphorus) with pyrites and sulphur (4.90, 4.91). Commercially, it is made by adding the elements to some preformed decasulphide in an inert atmosphere. The exothermic heat of reaction enables continuous distillation of the product to occur. 

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