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

作者：Wang, Meng; Hu, Hui-ping^*; Liu, Jin-wei

来源：Transactions of Nonferrous Metals Society of China, 2017, 27(2): 429-439.

DOI：10.1016/S1003-6326(17)60049-9

• goethite
• dissolved organic compound
• settling performance
• adsorption mechanism

Goethite, a typical iron-containing monomineral in red mud, was synthesized under the simulated Bayer digestion condition during the alumina production. The effects of dissolved organic compounds including sodium formate, sodium acetate, sodium oxalate, sodium salicylate and disodium phthalate on the settling performance of goethite slurries were studied. The settling performance of the slurries was also investigated with the addition of self-made hydroxamated polyacrylamide flocculant (HCPAM). The adsorption mechanism of dissolved organic compounds on the goethite surfaces was studied by FT-IR and XPS, respectively. The results show that the addition of organic compounds lowers the settling performance of the slurries and a deterioration in settling performance is observed in the order of sodium oxalate > sodium salicylate (similar to disodium phthalate) > sodium formate > sodium acetate. Moreover, HCPAM can efficiently eliminate the negative effects of sodium formate, sodium acetate and sodium oxalate on the settling performance of the goethite slurries, but it can only partially improve the settling performance of the goethite slurries containing sodium salicylate or disodium phthalate. FT-IR and XPS results show that these organic compounds are chemically adsorbed on the goethite surface.

• 出版日期2017-2
• 单位中南大学