Flotation Separation of Diaspore and Kaolinite by Using a Mixed Collector of Sodium Oleate-Tert Dodecyl Mercaptan

Abstract

Sodium oleate (NaOl), a collector in diaspore flotation, has been widely used for more than 30 years, while its low selectivity becomes an issue under today's process requirement. This study introduced tert dodecyl mercaptan (TDM) together with NaOl as a mixed collector to improve selectivity in diaspore flotation. We found that using the mixed collector of NaOl/TDM (total concentration 0.1 mM, the molar ratio 8:2 of NaOl: TDM) at pH = 9-10 significantly effectively separated diaspore and kaolinite. Comparing the recovery of Al 2 O 3 and the ratio of Al 2 O 3 to SiO 2 (A/S) treated by NaOl/TDM (pH = 9) and NaOl (pH = 10), the Al 2 O 3 recovery and A/S in concentrate for NaOl/TDM are 7.5% and 2.2 higher than that for NaOl in mixed mineral flotation. Also, surface tension measurements, Zeta potential measurements and Fourier Transform Infrared (FTIR) spectra analysis were used to examine its selectivity from a flotation mechanical perspective. Surface tension measurements show that mixed collector NaOl/TDM has stronger surface activity and hydrophobic association than NaOl. The results of Zeta potential measurements and FTIR spectra analysis indicate that NaOl and TDM can selectively co-adsorb diaspore through physical adsorption. Moreover, the adsorption of TDM promotes the adsorption of NaOl on diaspore. However, when NaOl/TDM treats on kaolinite together, TDM can hardly adsorb on mineral surface, nor can it promote the adsorption of NaOl.

Low-Temperature Flotation Separation of Diaspore from Kaolinite by Using a Mixed Collector

“…The preliminary single mineral flotation tests showed that when the temperature was 298 K, the selection effect of the NaOl/TDM collector on the diaspore was better than that of NaOl or TDM alone [19]. Previous studies [19] have shown that the optimal pH conditions for NaOl, TDM and the mixed collector NaOl/TDM are 10, 9 and 9, respectively.…”

“…The preliminary single mineral flotation tests showed that when the temperature was 298 K, the selection effect of the NaOl/TDM collector on the diaspore was better than that of NaOl or TDM alone [19]. Previous studies [19] have shown that the optimal pH conditions for NaOl, TDM and the mixed collector NaOl/TDM are 10, 9 and 9, respectively. The optimum molar ratio of NaOl to TDM in the mixed collector is 8:2 at 298 K. Figure 3 shows the effect of the dosage of NaOl, TDM and NaOl/TDM on the flotation recovery of the diaspore and kaolinite under the optimal pH condition at 298 K in the single mineral flotation tests.…”

Application of Waste Engine Oil for Improving Ilmenite Flotation Combined with Sodium Oleate Collector

“…The sodium oleate (NaOL), as a typical and commercial collector for ilmenite flotation [6,8], has the characteristics of strong collecting ability but large dosage. The main optimization approach for ilmenite flotation is NaOL modification or combination with other reagents [9][10][11][12][13][14][15]. However, the route of NaOL modification is long and costly.…”