Cyanide Gold Leach Waster Water Bearing High Copper And High Thiocyanate Treated By Comprehensive Treatment

Aiming at the excessive consumption of sodium cyanide and the lower goldleaching rate caused by impurity ion accumulation in the process of cyanide leachwaster water circulation, Fractional precipitation and ion exchange resin were used todecreased Cu(CN)2--3、SCNand other ions concentration,the treated water was back tothe leach system, cyanide gold leach solution was realized "zero" emissions.Based on the analysis of Fe(CN)4-6and SCN-in leach gold waster waterinterference with adsorption and desorption process of ion exchangeresin.firstly,thermodynamics and kinetics of Fe(CN)4-6and SCN-onto201×7fiber werestudied. Results show that Fe(CN)4--6and SCNadsorption onto the resin can occurspontaneously, the process conforms to Langmuir and Pseudo-second order from298Kto313K, the ion exchange process is entropy and endothermic,.At room temperature,Fe(CN)4-6and SCN-in cyanide gold leaching solution are easy to be adsorbed onto theresin,the process is mainly controlled by the film diffusion at the initial stages,but bythe diffusion gap at the late stages. Fe(CN)4-6and SCN-exchanged to the Stern layer arestrongly associated by the resin functional group and leads to "iron" poisoning of resinfor generating Zn2Fe(CN)6、Cu2Fe(CN)6andCuSCN, which adhere to the resin duringthe process of cyanide removed from loaded resin with H2SO4.On the basis of the above experiment, Effect of ZnSO4and CuSO4on Cu(CN)2-3、SCN-precipitation effective and coexisting ions were studied.Results show that theprecipitation rate of Copper and SCN-reaches about98%and88%when ZnSO4and CuSO4added1.8times and1.6times of the theoretical amount at room temperature for1h.At the same time, Fe(CN)4-6is also precipitated during zinc sulfate precipitatesCu(CN)2-3；the concentration of S2O2-3, SO2-3and Cu are reduced during CuSO4precipitates SCN-。Experimental results of the depth process precipitated liquid with ion exchangeresin show that the concentration of CN-、Cu和SCN-are descend0.03mg/L、1.25mg/Land0.4g/L when ion exchange resin added0.8g in100mL at room temperature for50minutes，the processed solution is returned to leaching system for recycling.