The extraction of chromium(III)oxide from chromite concentrate can be achieved through various methods, one of the most common being alkaline roasting using sodium chromate an‎d sodium dichromate. Process optimization particularly in the leaching stage can significantly enhance recovery efficiency by adjusting operational parameters such as temperature, time, an‎d liquid-to-solid ratio.In this study, the focus was on optimizing the leaching stage of domestically roasted chromite concentrate. A chromite concentrate with a grade of 32.05% was mixed with sodium carbonate at a ratio of 2.5:1 an‎d a particle size of 75 µm. The mixture was roasted at 1000 °C for 2 hours. The roasted product was then leached in water under varying conditions: temperatures ranging from 25 to 85 °C, durations from 1 to 60 minutes, an‎d liquid-to-solid ratios of 2.5:1, 5:1, an‎d 10:1.To convert sodium chromate into sodium dichromate, sulfuric acid was added. Subsequently, a sulfur emulsion was introduced into the boiling sodium dichromate solution, resulting in the formation of chromium hydroxide. This intermediate was then calcined to produce chromium oxide.Results indicated that sodium chromate dissolved effectively in water at 45 °C, achieving a recovery rate of 73.69%. A 12-minute leaching time yielded a recovery of 63.14%, while increasing the liquid-to-solid ratio from 5:1 to 10:1 improved recovery from 56% to 63%. Acid addition an‎d pH adjustment from 12.3 to 8 further optimized the process, raising chromium recovery to 63.45% an‎d facilitating the conversion of sodium chromate to sodium dichromate. Finally, calcination of chromium hydroxide at 800 °C for 30 minutes produced chromium oxide with a purity of 98.565%. Key Words Alkaline roasting, Localization, Leaching, Sulfur emulsion, Chromium(III)oxide

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