Pyrolysis liquid of pine as a new source of depressant in the flotation separation of fluorite and calcite

In this study, the pyrolysis liquid of pine (PLP) was used as a novel depressant to separate fluorite from calcite. Flotation experiments revealed that the PLP can depress the flotation of calcite, whereas its impact on fluorite was minimal. Fourier transform infrared (FTIR) spectroscopy showed that the substance adsorbed onto calcite surface hindered oleate adsorption onto calcite, but had minimal impact on fluorite. Gas chromatography-mass spectrometry analysis results presented that the main components of PLP were phenols, aldehydes, furans, and ketones. Among them, catechol and other phenolic compounds played major roles in the depression of calcite as revealed by FTIR and time -of -flight secondary ion mass spectroscopy. The increased phenol content resulted in a more pronounced depressant effect of PLP prepared at 800 C-degrees on calcite compared with that of PLP prepared at 500 C-degrees. This study provides a new perspective on the potential application of pyrolysis fluid in mineral flotation.