Cottonseed oil biodiesel used as a renewable collector for coking coal flotation

Hydrocarbon oil collectors used in coking coal flotation are nonrenewable resources, and their collecting performance is difficult to meet current industry needs. In this study, cottonseed oil biodiesel (CSOB) was prepared from cottonseed oil by alkali-catalyzed transesterification, and experimental studies on flotation of 1/3 coking coal were carried out. The results showed that the clean coal yield was about 75% when the use of CSOB was 2000 g t-1. The results of contact angle, FTIR and XPS tests showed that the oxygen-containing groups of CSOB were adsorbed on the hydrophilic spots on the surface of coal particles, and the surface hydrophobicity of coal particles was increased. The ash level of the clean coal with the addition of CSOB during flotation was essentially the same as with the addition of an equivalent amount of diesel oil.