Synthesis and flotation performance of a novel low-foam viscous cationic collector based on hematite reverse flotation desilication system

Traditional cationic collectors generally exist some disadvantages, such as high foam viscosity and difficulty in defoaming, which worsening the flotation separation effect. Herein, a novel cationic collector-dodecyl trihydroxyethyl ammonium bromide (DTDAB) with low-foam viscous was synthesized to optimize the reverse flotation system of hematite ore, which was achieved by introducing three hydroxyethyl groups into the nitrogen atoms of dodecyl trimethyl ammonium bromide (DTAB). The analysis of foam collapse performance indicated that the introduction of hydroxyl groups into hydrophilic head groups of DTAB reduced the interface surface tension and bubble coalescence, which were consistent with the design expectations. Meanwhile, flotation behaviors were systematically studied, and the results showed that the concentrates with 63.89 % total iron (TFe) grade and 89.27 % total iron recovery was obtained at pH 6.81, when the concentration of DTDAB and starch was 20 mg/L and 5 mg/L, respectively. Besides, the possible flotation mechanism was further studied by means of contact angle, Atomic force microscope (AFM), Fourier transforming infrared spectra (FT-IR), X ray photoelectron spectroscopy (XPS), and Density functional theory (DFT) calculation. The results comfirmed that the adsorption between DTDAB and quartz was caused by electrostatic force and hydrogen bonding affinity. In conclusion, it can be confirmed that the novel cationic collector DTDAB with low-foam viscous has the potential for the hematite reverse flotation desilication.