Gold extraction with poly(diallylamine) resins

Weak-base poly(diallylamine) resins have been synthesised and tested for gold adsorption properties in metal-containing solutions ranging all the way from strong acid (aqua regia) to strong base (complex cyanide solutions, pH 7–14). These resins show high capacity, up to 5 mmol/g dry resin, and good gold-selective properties for much of this pH range and in many different types of solution, including contaminated wastes. However, the slow dissolution of uncrosslinked polymer chains trapped in the resin matrix limits the gold adsorption properties at low gold concentrations (below 5 mg/dm³).