Recovering finely divided coal by froth flotation - in presence of a bis:alkyl sulpho-succinate salt giving reduced ash content

摘要

Recovery of finely-divided coal comprises treating its aq. suspension with a sulphosuccinate of formula (I) (where R=3-20C opt. branched alkyl; M is a water-solubilising cation). The mixt is then froth floated to give, as the floating material, a coal concentrate. Pref. (I) have M=Na and R=isobutyl amyl, (cyclo) hexyl, 2-ethylhexyl or isodecyl. Pref. the mixt. also contains a frothing agent (II) esp a mixt. of 4-8C alcohols. The recovered coal has a reduced ash content e.g. about 6% compared with 42% for untreated coal.