REMOVAL OF ORGANICS FROM BAYER PROCESS STREAMS

摘要

A process for removing organic material from the Bayer process wherein, (a) bauxite is digested in sodium hydroxide to form a solution of sodium aluminate (b) aluminium hydroxide is precipitated from the solution and (c) is calcined to form alumina, characterized in that any of the process liquors is treated with manganese dioxide to oxidize the organic material. In particular oxalate can be removed from the seed wash liquor by oxidation with manganese dioxide in a fluid bed reactor.