PHENOL-FORMALDEHYDE BASED WEAK-BASE RESINS FOR THE RECOVERY OF GOLD

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.