Refining of gold that gold paste or compound essence is melt
2020-08-12 09:54Introduction：Refining of gold that gold paste or compound essence is melt ed or pour ed beads - Separation of gold and silver with nitric acid The separation of gold and silver by nitric acid is a kind of wet refining, similar to that of sulphuric acid
Refining of gold that gold paste or compound essence is melted or poured beads - Separation of gold and silver with nitric acid
The separation of gold and silver by nitric acid is a kind of wet refining, similar to that of sulphuric acid. However, in the case of the electric MPF mud produced by the CIL plant, the phenomenon of gold wrapped in silver may occur due to the alternating deposition of gold and silver during electrolytic deposition. In addition, if the electrowinning voltage and current are not properly controlled, a gold coating may be formed on the surface of gold-loaded steel wool. Under such circumstances, the gold and ingots containing only about 90% gold can only be obtained by the above two processes. In order to meet the needs of the market, we must further remove impurities and improve the finished gold purity . The following is an introduction to the method that can be used to deal with the gold slime of CIL plant and obtain gold in different purity finished products.The principle of this process is still the separation of gold and silver by nitric acid, which differs from the direct nitric acid method by melting 1 / 3 ~ 1 / 2 of the total amount of gold mud in an intermediate frequency electric furnace. Partial consumption of "Gold and Silver Alloys" formed in Electrolytic deposition process and adverse effects on the Separation of Gold and Silver. The subsequent procedures for separation of gold and silver are basically the same as those mentioned in this chapter, but the bead throwing operation has a great impact on the separation effect of gold and silver. The bigger the proportion of beads is, the higher the finished gold purity will be. Accordingly, the workload and the finished purity will also increase. Generally speaking, throwing beads and gold mud accounts for 30%~50% of the total amount of gold mud. The gold content of finished products can reach more than 96%. The finished product gold produced by this process can completely meet the requirements of the people's Bank of China.
The following points should be paid attention to in the process of melting gold mud and throwing beads:
1. According to the amount of silver in the gold mud, the ratio of gold to silver is 1.0: (2. 7 ~3. 3) add enough silver should be added to melt together.
2. When throwing beads, the temperature of the gold and silver melt is not easy to be too high or too low. When the temperature is too high, the beads are granular and the specific surface area is small, which is not conducive to the reaction. When the temperature is too low, the spilt beads are easily glued to a lump. General bead temperature should be controlled at about 1150 ℃, under these conditions the beads are fine flake shape.
3. When throwing beads, the temperature of water should not be higher than 35 ℃. Generally use cold water pipe while pouring beads, while strengthening the water agitation.
4. When throwing beads, the flow of molten alloy from the furnace should be controlled to be fine and uniform, so as to prevent the spilt beads from forming large blocks.
