The Research On Cyanide-free Gold Compounds Of Isolation And Purification And Application Properties

The research purpose of this thesis was to use201×7(717) strongly basic anion exchange resin for a new cyanide-free gold solution chloride ions separation. The property of electroplating based on this solution was studied and the quality index checked by using the requirement of modern electronic industry. And then from the point of production safety and environmental protection to estimate the substitute for the cyanide process was presented in the paper. It’s hoped that it could take the place of the traditional cyanide gold solution with extremely toxicity and environmental pollution.At present, it’s very common occurance that use different kinds of ion exchange resin exchange separation of chlorine in research of solution. But there had not been any related report about a cyanide-free gold solution chloride ions separation with ion exchange resin. The research purpose from that point was to verify the feasibility of this method, and get the best operating conditions.Project could be divided into several parts and shown as follows:1)To separate chloride ions from the new cyanide-free gold solution. The adsorption properties of201×7(717) strongly basic anion exchange resin to the chloride ion in cyanide-free gold solution was investigated. Examine the temperature, time, concentration of the influence of this process.2)The electroplating performance of cyanide-free water-soluble gold solution was investigated under different electroplating time, current density and temperature.The conclusions are:1) In303K condition, the static saturated exchange capacity of201×7(717) strongly basic anion exchange resin could reach0.7908mmol/g. Even though the solution to1500mL, the dynamic saturated exchange rate of this resin was still more than92%. Chloride ions could be wash down completely from the resin with5%sodium hydroxide solution.2) The thermodynamic study of the exchange process showed that the chloride ion exchange process is spontaneous and endothermal, and the entropy is positive.3) In303K condition, the dynamic saturated exchange capacity of201×7(717) strongly basic anion exchange resin could reach0.7128mmol/g. The dynamic saturated adsorption rate of this resin could be more than95%, and gold loss rate was less than2%.4) The condition of electroplating was:gold solution concentration of1g/L, current density1.0A/dm2, temperature318K-323K, operation time lmin, and the related rate of deposition was0.27μm/10s. The binding force and luster for the electroplated panels could meet the quality specification.