Comprehensive Recovery Of Multi-metal In Dilute Sulfate Solution

This paper separated and enrichmented Cu2+and Co2+in multi-metal dilutesulphate solution using the D418macroporous amino phosphoric acid type chelatingresin. AAS and iodimetry and other methods were used to determine the content ofmetal ions. This paper also develops a reasonable process route to recycle copper andcobalt efficiently, which solves the long difficult problem to recycle multi-metal indilute sulfate solution and provide a theoretical basis and technical guidance for thehydrometallurgy and related industries. Through applying an ultrasonic device toaccelerate desorption of metal ions, which facilitates desorption of hard-elution metalions, futhermore, this method greatly shorten desorption time and improve theefficiency of desorption per unit time, and also conducive to the regeneration of theresin.The main contents and results are as follows:1. First exploring the D418resin on adsorption of single component Cu2+andCo2+in the dilute sulphate solution. It was found the optimal adsorption conditions tothe single component through the static adsorption experiment. Through studying theacidity, adsorption time, initial metal ions concentration and the dose of resin on theinfluence of resin adsorption properties we designed the two-component Cu2+andCo2+adsorption experiments to explore the optimum conditions for separating andthen amplified the experiments. Experimental results showed that, the optimal pH ofadsorption Cu2+and Co2+was5.0, under the optimum conditions, the maximumadsorption capacity were170mg/g and130mg/g respectively. It requires threeadsorption stages in50mL Cu/Co (2000/300) system, the total separation time is9.5h and the total amount of resin is0.64g. At last, the adsorption of Cu2+achievedabove90%and the Co2+almost completely stayed in the adsorption raffinate, which realized the initial aim to separate copper and cobalt and then enlarged theexperiments40times, the total adsorption of Cu2+was still above90%but a very tinyamount of cobalt was adsorbed on the resin, above95%Co2+remained in theadsorption raffinate, which has a good separation effect.2. Considering the separation of copper and cobalt requires three adsorptionstages in the above-mentioned process, which generally needs more than9h,especially for lower concentrations of copper and cobalt, more time is required. Inorder to shorten the time and reduce costs, we choose another route, putting sufficientresin dose one time to adsorb copper and cobalt. We explored the optimal dose ofresin and adsorption time in the two-component of different proportions of copper andcobalt system. The results showed that in the system of100mL Cu/Co (2000/30)system, putting2.7g resin one time, after adsorbing4h, more than97%of copper andcobalt were completely adsorbed. The separation will be done in the subsequentexperiment. Theoretically this method would increase the amount of resin but giventhe resin can be regenerated to recycle. Therefore, the process route is moreeconomically viable.3. By introducing an ultrasonic device to accelerate the elution of metal ions onthe resin. The experiments explored the concentration of desorption solution,solid-liquid ratio, ultrasonic time, ultrasonic temperature and ultrasonic power on theimpact of eluting metal ions. Comparing with the static desorption, we can find thatthe ultrasonic desorption can greatly shorten desorption time and improve theefficiency of desorption, furthermore, it can significantly increase the absorptionproperties of the resin in a certain range. By exploring the optimum ultrasonicdesorption conditions can find the optimal routing to elute metal ions. The resultsshowed that in10minutes, the static desorption of desorption rate of copper was70%but in ultrasonic desorption it had reached100%. When desorbed hard-eluted metalions such as gold, we could find the unique advantages of ultrasonic desorption.Whenusing Static desorption25min, gold desorption rate was41.34%. While using theultrasonic desorption, gold desorption rate was79.08%, which almost doubled thegold desorption rate. Therefore, when eluted other metal ions on the resin, we can promote the use of ultrasonic desorption method for it is easy to operate and control.