Method for recovering gold from thiourea leachate
There are many methods for recovering gold from thiourea leaching solution. The main methods studied include metal displacement precipitation method, activated carbon adsorption method, ion exchange resin method and electrowinning method. Since activated carbon adsorption method is better, only activated carbon adsorption is introduced here. law. SMT nozzles are used to pick up components from component feeders and placing the components to PCB board after solder paste printing process. These nozzles are used by high speed pick and place and flexible component mounter machines. We are offering all types of SMT nozzles for almost All brands and models of SMT machines. We also provide OEM nozzles for special components aside from standard SMT nozzles. We distribute original and high copy units SMT nozzles. SMT Nozzle,SMT Panasonic Nozzle,SMT LED Nozzle,Original SMT Nozzle,Nozzle For Smt,Smt Nozzle Price,Smt Nozzle Holder ShenZhen KDW Electronics Co.,Ltd , https://www.smtsplicetape.com
The activated carbon adsorption method is a method for adsorbing and recovering gold from activated carbon by leaching out of the sulphur urea. The Act includes the following two processes:
1) Carbon adsorption The thiourea leaching gold from the slurry is adsorbed on the activated carbon. Adsorption conditions: the concentration of carbon in the slurry is 20g / l, the concentration of gold is 3 ~ 10g / t, the concentration of thiourea is 2 ~ 5g / l, the concentration of ferric ions is 1.5 g / l, the concentration of sulfuric acid is 10 g/l. The adsorption rate of gold on charcoal is very fast. After 90 minutes, 99% of the gold is adsorbed on the charcoal. Under these conditions, the gold adsorption capacity reached 680 g/t.
2) Carbon desorption The gold is desorbed into the solution from the activated carbon, and the gold is recovered from the desorbed liquid containing rich gold. It is easy to desorb gold from the activated carbon using an acetone-containing thiourea solution. The process conditions and technical parameters are as follows: a desorbent containing 100 g/l of thiourea and 90 g/l of sulfuric acid is prepared with 30% acetone at a temperature of 20 ° C, and the flow rate of the desorbed solution is 1.25 carbon bed volume / hour, 24 After the hour, 95% of the gold was desorbed from the carbon having a gold adsorption capacity of 11.25 kg/t, and the carbon contained in the carbon was 520 g/t after desorption.