Phase Composition of Interstitial Clay and Gas Emissions on Heat Treatment

Abstract

When interstitial clay, which is the waste from shale combustion, is fired at 250°C, the decomposition of organic matter results in the emission of H₂, CO, SO₃, and CO₂ from the ceramic samples. At 350–550°C, the content of oxidant (oxygen) and neutral gas (nitrogen) is markedly less. At 550–750°C, no sharp decrease in their content is observed. At 750–1000°C, the decrease is slight. At 1000°C, mainly CO is formed. At 1050°C, the fired sample contains practically no organic compounds. More complex compounds (anorthite, diopside) are formed, with increase in the mechanical strength.