Mineral transformations during high temperature treatment of anthracite

摘要: Abstract SEM/EDX analysis has been applied in order to assess the mineralogical transformations occurring during high temperature treatment of several different anthracites. At 1000 °C (carbonization) loss CO2 from carbonates, S sulfides and OH and/or H2O clays occurs, transforming these minerals other inorganic phases such as lime, pyrrhotite, (Na, Mg) K-aluminosilicates, among others. Heat carbonized samples up 1500, 2000, 2500 °C resulted in: i) a decrease oxygenated phases, which are transformed higher silicates (grossite, anorthite, kushiroite, etc.); ii) carbide formation (SiC, TiC or Al4C3) by carbothermal reactions; iii) alloys, especially Pb–Sn alloy; iv) iron silicides (Fe2Si), phosphides (Fe3P), nitrides (TiN AlN). The new mineral closely related matter raw anthracite samples. Thus, richer Ca–Mg (carbonates phosphates) produced monticellite, pyrope, gehlenite, grossite kushiroite; Al-bearing (boehmite diaspore) gave rise mullite, corundum spinel; Si–Al bearing (clay minerals) were associated with panunzite, plagioclase cristobalite. highest process majority elements vaporized, Ti seems be only element original that withstands 2500 °C.