Example: Industrial leaching of gold leaching using cyanide is often limited by transport of oxygen due to its relatively low solubility, 0.25 mol m, in aqueous solutions. Using Fick's "} first law and the steady state relationships for fluxes of species according to following reaction, calculate the minimum cyanide concentration required so that no excess cyanide exists at the reaction interface. Given that the diffusion coefficients for O2 and CN-are 2.76X10-9 m 5-1 and 1.83x10-9 m2 s-1, respectively. 9 2 Au +4CN +O2 + 2H,02 Au(CN)2 + H2O2 + 2OH- C," =-k,C) D j J lim j =- 8