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The environmental problems resulted from the traditional production process of chromic oxide have spawned worldwide public concerns.With a design objective to eliminate pollution at the source, a clean production process of chromic oxide was developed, and the clean process has successfully achieved higher resource utilization efficiency and zero emission of the chromium-containing residue.In the clean process, the chemical conversion from chromite ore to chromic oxide includes four steps: (1) the oxidative separation of the trivalent chromium in chromite ore to hexavalent chromium via hydrometallurgical processing; (2) the reduction of hexavalent chromium to trivalent chromium with hydrogen; (3) the hydrolysis of alkali metal chromium oxide to chromic hydroxide; and (4) the thermal decomposition of chromic hydroxide to chromic oxide.