4J A Gonzalez, M del C Ruiz. Bleaching of k-aolins and clays by chlorination of iron and titanium [J]. Applied Clay Science, 2006(33): 219-229.
5F Veglio. Factorial experiments in the develo-pment of a kaolin bleaching process using thiourea in sulphuric acid solutions[J].Hydrometallurgy, 1997(45): 181-197.
6Bcnnct H, Rccd R A. Chemical Methods of Sili-cate Analysis [M]. London: A Handbook Academic Press, 1971: 272-289.
7Al-Mobarak N A. Effect of oxalic acid on the dissolution of magnetite coupled with iron of various surface area [J]. Int J Electrochem Sci, 2008,3 : 666-675.
8Taxiarchou M, Panias D, Douni I, et al. Dissolution of hematite in acidic oxalate solutions [J]. Hydrornetallurgy, 1997, 44(3): 287-299.
9Pansu M, Gautheyrou J. Handbook of soil analysis: mineralogical, or- ganic and inorganic methods [M]. Netherlands: Krips bv, Meppel, 2007: 920-924.
10Panias D, Taxiarchou M, Paspaliaris I, et al. Mechanisms of dissolution of iron oxides in aqueous oxalic acid solutions [J]. Hydrometallurgy, 1996, 42(2): 257-265.