Rutile flotation with Pb2+ ions as activator: Adsorption of Pb2+ at rutile/water interface

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2016-10, Vol.506, p.431-437
• Main Authors: Li, Hongqiang, Mu, Shunxing, Weng, Xiaoqing, Zhao, Yunliang, Song, Shaoxian
• Format: Article
• Language: English
• Subjects: Adsorption; Flotation; Lead ion; Rutile
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2016.06.046

Adsorption of Pb2+ on rutile in aqueous solutions at 30°C. [Display omitted] ⿢Pb(OH)+ interacted with the Ti-OH on rutile surface to form surface complex Ti-O-Pb+.⿢Complex Ti-O-Pb+ greatly improve the adsorption of SHA and rutile floatability.⿢The adsorption followed the Langmuir model. The adsorption of Pb2+ at the rutile/water interface has been studied for the activation of rutile flotation with salicyl hydroxamic acid (SHA) as a collector in this work. This study was performed through measurement of the zeta potential, adsorption capacity, calorimetry and X-ray photoelectron spectroscopy. The experimental results showed that the adsorption of SHA on rutile and the flotability of rutile were significantly improved by the addition of Pb2+. This improvement was attributed to the specific adsorption of Pb2+ in the form of PbOH+, which interacted with the Ti-OH at the rutile surface and formed a surface Ti-O-Pb+ complex. This adsorption followed the Langmuir model. It reversed the zeta potential sign of rutile at pH 5.5⿿6.8 and had a heat of adsorption of ⿿46.71kJ/mol, suggesting the occurrence of a chemiosorptive process.