Oxidized coal flotation enhanced by adding n-octylamine

ABSTRACT

Oxidized coal is difficult-to-float using conventional diesel as the collector due to the abundant oxygen-containing groups on coal surface. In this study, a short-chain cationic amine, n-octylamine, was added into diesel in 1:4 ratio for enhancing oxidized coal flotation. X-ray photoelectron spectroscopy (XPS) was used to identify the interaction mechanism between diesel-n-octylamine mixture (DO) and oxidized coal. The results showed that the flotation yield using 500 g/t DO mixture was much higher than that of using 2000 g/t diesel under a similar ash content of clean coal. The addition of n-octylamine was proven to be an effective way to lower the oily collector consumption in oxidized coal flotation. XPS showed that electrostatic bonding between n-octylamine and negative-charged hydrophilic sites on oxidized coal surface was responsible for the enhancement of flotation recovery using DO as the collector.

KEYWORDS:

• Diesel
• electrostatic bonding
• flotation
• n-octylamine
• oxidized coal

Acknowledgments

This research was supported by the Fundamental Research Funds for Central Universities (Grant 2018BSCXB10) and Postgraduate Research & Practice Innovation Program of Jiangsu Province for which the authors express their appreciation.