Raman spectroscopic study of phosphogypsum thermal reduction with the carbonaceous material.Elemental sulphur (S) can be produced from hydrogen sulphide (H2S) in a PiPco or Iron process.  In turn H2S can be stripped with carbon dioxide (CO2) from calcium sulphide (CaS) obtained from the thermal reduction of phosphogypsum with carbon.  The reaction pathway for the thermal reduction of the phosphogypsum with graphite was studied using thermogravimetric analysis and in situ Raman spectroscopy. 
THERM