Abstract: There is usually a lot of alkali in the red mud，which not only limits its comprehensive utilization，but also is a waste of resources.Recovery method of alkali in the red mud was mainly researched.Alkali liquor was obtained by treating red mud with atmospheric lime method and it was recycled to reach alkali enrichment，then passed into the carbon dioxide gas to make it into sodium bicarbonate saturated salt solution，and added n-butyl alcohol for extraction，thereby alkali in red mud could be recovered.Results indicated that after four times recycling of alkali liquor，the mass concentration of Na element in the solution reached to 25.6 mg/mL；and when the volume ratio of n-butyl alcohol to saturated sodium bicarbonate solution was 5∶1 and reaction temperature was 35 ℃，the recovery rate of sodium bicarbonate was the largest and the morphology of sodium bicarbonate crystal obtained by recovery was good.

Key words: red mud, concentration, alkali recovery