I. Tyc et Br. Green, PHENOL-FORMALDEHYDE BASED WEAK-BASE RESINS FOR THE RECOVERY OF GOLD, Solvent extraction and ion exchange, 12(4), 1994, pp. 817-830
In a process for the recovery of gold-cyanide with a weak-base resin,
it is desirable that the resin should load gold at the natural pH of t
he leach liquor and be stripped by an aqueous alkali. The present work
explores, for such a resin, the potential of a phenol-formaldehyde po
lymer matrix which, it was thought, would facilitate the stripping of
gold. Unexpected loading behaviour of a resin with an imidazoline acti
ve group is rationalized from results obtained during its titration. I
t is concluded that a phenol-formaldehyde matrix might limit the upper
pH at which a resin can load, and its effect on pH functionality will
depend on the concentration of phenolic groups. Magnetic separation i
s a possible technique for separating a resin from a pulp. The method
of synthesis of phenol-formaldehyde polymers can be adapted to prepare
composite resins containing magnetic materials.