A novel reductive alkali roasting of chromite ores for carcinogen-free Cr6+-ion extraction of chromium oxide (Cr2O3) – A clean route to chromium product manufacturing!

•The reduction of chromite ores with alkali eliminates the risk of carcinogenic Cr6+- ion production during the extraction of chroimum oxide and Fe-Cr-alloy. The alumina is also extracted as a by-product of the process.•The CO generated in the process is partly utilized for energy generation by combustion via CO+0.5O2 = CO2 reaction. Less than 10 % of CO2 may be sequestrated for alumina recovery.•There is no solid and water waste in the process which contains carcinogenic Cr6+- ions.