Aq. coal dispersion contains ionic dispersant - contg. ethylene oxide polymer chain and hydrophobic group, attaching to coal

摘要

The dispersion contains: (i) at least 55 wt.% pulverised coal, the surface of which has been modified by adsorption of zwitterionic or other hydrophobising substances, added during flotation and/or dewatering; (ii) water; and (iii) as dispersant, an ionic surfactant polymer, contg. a hydrophobic group (pref. aromatic) for attachment to the coal and a water-sol. group based on polymerised ethylene oxide of mol. wt. exceeding 1000. Coal flotation may be effected with the addn. of one or more of aliphatic alcohols, frothing agents, zwitterionic surfactants (e.g. lecithin) and alkyl sulphosuccinates. Surfactants which may be added during dewatering are alkylaryl sulphonates and alkyl-sulphosuccinates. The dispersion is useful for transporting coal, and as an alternative to oil for steam prodn. and heating. It has a very long storage life.