Investigation of gasification atmosphere on nickel and vanadium transformation of petroleum coke by thermodynamic equilibrium calculation

The evolution of Ni and V species during CO2/H2O/H2O+O2 gasification is investigated at 600 °C–1500 °C. The high S content inhibits the conversion of Ni3S2 into Ni and facilitates the formation of FeS, thus inhibiting the formation of FeV2O4(s). During CO2 gasification, Ni exists in Ni3S2 and converts into Ni at above 1200 °C. The V compound undergoes a mutual conversion between V2O3 and FeV2O4. Ni in Handan petcoke converts into AlNi2O4 and FeNi2O4 during H2O gasification given the high content of Fe and Al. The O2 promotes the decomposition of spinel (FeAl2O4 and FeNi2O4), thereby reserving the Fe in slag-phase FeS. The difference in the mineral transformation between samples increases with the oxidizability of the gasifying agent.