Gold dissolution and activation in cyanide solution: kinetics and mechanism

Recovery of platinum group metals from spent catalysts: A review

“…), followed by two steps of pressure cyanide leaching under conditions of sodium cyanide concentration 10 g/L, liquid to solid ratio 4, leaching temperature 160 °C, leaching time 1 h, system pressure 2.0 MPa, stirring speed 800 rpm, the recoveries of Pt, Pd and Rh were 95~96%, 97~98% and 90~92%, respectively. In cyanide leaching process, the reaction rate has been proposed to be controlled by a surface chemical reaction, similar to gold cyanide reaction mechanism (Wadsworth et al, 2000). In the leaching process, special equipment must be used, and the produced waste poisonous sodium cyanide will lead to an environmental problem, and PGMs leaching are low and unstable.…”

Functionalization of Fe₃O₄/SiO₂ with N-(2-Aminoethyl)-3-aminopropyl for Sorption of [AuCl₄]^-

“…After reaching the equilibrium stage, the gold(III) on the surface of adsorbent is desorbed by contacting with a leaching agent such as cyanide solution. However it's low desorption rate and toxicity made cyanide less favorable as a leaching agent [11]. Based on the environmental problems, environmentally friendly solvents is required for desorption of gold from the adsorbent.…”

Real time optimization based on a serial hybrid model for gold cyanidation leaching process

“…An electrochemical mechanistic model based on the shrinking-particle model was presented by Crundwell and Godorr (1997), in which the mathematical model of leaching reactions was used to account for leaching electrochemical mechanisms, gold surface passivation and gold particle shrinkage. Wadsworth et al (2000) proposed a mechanistic model in which the surface reactions were thought to control the gold dissolution rate kinetically. Afterward De Andrade Lima and Hodouin (2006) proposed a mechanistic model of GCLP that consisted of mass conservation equations of gold in the solid phase, gold in the liquid phase and cyanide in the liquid phase.…”