Negative effects of dissolved organic compounds on settling performance of goethite in Bayer red mud

Application of ultrasonic-enhanced active seed crystals in the removal of sodium oxalate from alumina refinery waste liquor

“…After accumulating to a high amount for the organics especially Na 2 C 2 O 4 , the production process of alumina will be severely affected. For example, it can lower seed decomposition rate, reduce alumina production yield, prolong seed induction period, loss sodium hydroxide, decrease the particle size of aluminum hydroxide, and generate odor gases, with lowering the alumina whiteness and even diminishing the red mud settling rate [19] , [22] , [23] , [24] , [25] , [26] , [27] . Given the considerable hazards caused by the organics to the Bayer process, much attention has been paid to the treatment of organic compounds from sodium aluminate solution including thermal treatment [25] , chemical precipitation [10] , photocatalytic degradation [28] , membrane separation [11] , and wet oxidation methods [29] .…”