Investigation of CTAB and DBP esters on low-rank coal flotation selectivity

ABSTRACT

To enhance low-rank coal flotation efficiency, dibutyl phthalate (DBP) and cetyltrimethylammonium bromide (CTAB) were used as collectors, respectively. The adsorption selectivity performance of CTAB and DBP on coal samples with different densities were characterized by the total organic carbon content, contact angle, and Fourier-transform infrared spectra. The results indicate that both DBP and CTAB greatly improved flotation yield compared with diesel, but only DBP can yield a concentrate with a low ash content. DBP had a higher adsorption capacity and bestowed a greater change in contact angle for low-density coal, while CTAB followed the opposite behavior. Furthermore, the ester group of DBP consumed the oxygen-bearing functional group and increased the alkane chain content on the coal surface, leading to a noticeable increase in hydrophobicity of the low-density coal sample.

KEYWORDS:

• Low-rank coal
• collector
• adsorption performance
• flotation
• selectivity

Additional information

Funding

This work was supported by the National Key R&D Program of China (2018YFC0604702) and National Nature Science Foundation of China (Grant nos. 51774286, 51574236).