A method for adding sawdust to remove silver from silver-containing tin alloy

Abstract

The invention relates to a method for adding wood bits into silver-containing tin alloy to remove silver and belongs to the technical field of nonferrous metal pyrogenic process smelting. First, silver-containing tin alloy is subjected to high-temperature full fusion, then, crude zinc is added into the molten silver-containing tin alloy, full stirring and dissolution are carried out, when temperature is lowered to 250-380 DEG C, wood bits with the weight five times of that of silver in the crude zinc are added, full stirring is carried out, residue dragging is carried out, and repeated working is carried out. When observed floating objects are black carbon granules, residue dragging is stopped, finally, liquid-state tin containing small amount of silver and a silver-zinc shell containing the carbon granules are obtained, and after the liquid-state tin is cooled, desilverization tin is obtained. The method is simple in technology, the process is safe and reliable, operation is convenient, cost is low, raw material universality is high, equipment is simple, and the tin alloy silver-containing range which can be processed is wide.

Description

technical field

[0001] The invention relates to a method for removing silver by adding sawdust to a silver-containing tin alloy, and belongs to the technical field of nonferrous metal pyrometallurgy. Background technique

[0002] In daily life, the general composition of widely used tin alloy solder is Sn55~63%, Pb30~36%, Ag0.1~0.2%, and the precious metal silver in tin alloy has huge economic value.

[0003] In the crude tin pyro-refining process, most tin smelters use continuous spiral crystallizers to remove lead and bismuth to obtain lead-tin eutectic alloys, which are called crude solder. Since lead is a good collector of precious metals, during the crude tin refining process, most of the silver enters the crude solder, and the crude solder with a silver content higher than 0.8% is also called silver-rich crude solder.

[0004] At present, electrolysis is generally used for the treatment of silver-containing tin alloys. Gold, silver and other metals cannot be dissolved...

Examples

Embodiment 1

[0018] Such as figure 1 Shown, this adds sawdust to the method for removing silver in silver-containing tin alloy, and its concrete steps are as follows:

[0019] Step 1. First, heat up 10 tons of silver-containing tin alloy (the silver content in the silver-containing tin alloy is 1.5g / t, and the rest is tin) to 450°C and fully melt it. 1:4 add crude zinc, fully stir to dissolve;

[0020] Step 2. Cool the silver-containing tin alloy treated in step 1 to 250°C, add sawdust whose mass is 5 times the silver in the crude zinc, stir well, remove the slag, repeat the operation, and observe that the floating matter is black carbon particles, stop removing the slag operation, and finally obtain liquid tin with low silver content and silver-zinc shell containing carbon particles, and the liquid tin can be desilvered tin after cooling.

[0021] Wherein the silver-zinc shell in step 2 is subjected to vacuum distillation to obtain crude zinc and silver; the crude zinc obtained by vacuu...

Embodiment 2

[0024] Such as figure 1 Shown, this adds sawdust to the method for removing silver in silver-containing tin alloy, and its concrete steps are as follows:

[0025] Step 1. First, heat up 10 tons of silver-containing tin alloy (the silver content in the silver-containing tin alloy is 5000g / t, and the rest is tin) to 500°C and fully melt it, and the molar ratio of silver in the silver-containing tin alloy to zinc in the crude zinc is 1 : 6 Add crude zinc, fully stir and dissolve;

[0026] Step 2. Cool the silver-containing tin alloy treated in step 1 to 300°C, add sawdust whose mass is 5 times the silver in the crude zinc, stir well, remove the slag, repeat the operation, and observe that the floating matter is black carbon particles, stop removing the slag operation, and finally obtain liquid tin with low silver content and silver-zinc shell containing carbon particles, and the liquid tin can be desilvered tin after cooling.

[0027] Wherein the silver-zinc shell in step 2 is ...

Embodiment 3

[0030] Such as figure 1 Shown, this adds sawdust to the method for removing silver in silver-containing tin alloy, and its concrete steps are as follows:

[0031] Step 1. First, heat up 10 tons of silver-containing tin alloy (the silver content in the silver-containing tin alloy is 25000g / t, and the rest is tin) to 550°C and fully melt it, and mix it according to the molar ratio of silver in the silver-containing tin alloy to zinc in the crude zinc: 1 : 9 add thick zinc, fully stir and dissolve;

[0032] Step 2. Cool the silver-containing tin alloy treated in step 1 to 380°C, add wood chips whose mass is 5 times the silver in the crude zinc, stir well, remove the slag, repeat the operation, and observe that the floating matter is black carbon particles, stop removing the slag operation, and finally obtain liquid tin with low silver content and silver-zinc shell containing carbon particles, and the liquid tin can be desilvered tin after cooling.

[0033] Wherein the silver-zi...

technical field

[0001] The invention relates to a method for removing silver by adding sawdust to a silver-containing tin alloy, and belongs to the technical field of nonferrous metal pyrometallurgy. Background technique

[0002] In daily life, the general composition of widely used tin alloy solder is Sn55~63%, Pb30~36%, Ag0.1~0.2%, and the precious metal silver in tin alloy has huge economic value.

[0003] In the crude tin pyro-refining process, most tin smelters use continuous spiral crystallizers to remove lead and bismuth to obtain lead-tin eutectic alloys, which are called crude solder. Since lead is a good collector of precious metals, during the crude tin refining process, most of the silver enters the crude solder, and the crude solder with a silver content higher than 0.8% is also called silver-rich crude solder.

[0004] At present, electrolysis is generally used for the treatment of silver-containing tin alloys. Gold, silver and other metals cannot be dissolved...

Examples

Embodiment 1

[0018] Such as figure 1 Shown, this adds sawdust to the method for removing silver in silver-containing tin alloy, and its concrete steps are as follows:

[0019] Step 1. First, heat up 10 tons of silver-containing tin alloy (the silver content in the silver-containing tin alloy is 1.5g / t, and the rest is tin) to 450°C and fully melt it. 1:4 add crude zinc, fully stir to dissolve;

[0020] Step 2. Cool the silver-containing tin alloy treated in step 1 to 250°C, add sawdust whose mass is 5 times the silver in the crude zinc, stir well, remove the slag, repeat the operation, and observe that the floating matter is black carbon particles, stop removing the slag operation, and finally obtain liquid tin with low silver content and silver-zinc shell containing carbon particles, and the liquid tin can be desilvered tin after cooling.

[0021] Wherein the silver-zinc shell in step 2 is subjected to vacuum distillation to obtain crude zinc and silver; the crude zinc obtained by vacuu...

Embodiment 2

[0024] Such as figure 1 Shown, this adds sawdust to the method for removing silver in silver-containing tin alloy, and its concrete steps are as follows:

[0025] Step 1. First, heat up 10 tons of silver-containing tin alloy (the silver content in the silver-containing tin alloy is 5000g / t, and the rest is tin) to 500°C and fully melt it, and the molar ratio of silver in the silver-containing tin alloy to zinc in the crude zinc is 1 : 6 Add crude zinc, fully stir and dissolve;

[0026] Step 2. Cool the silver-containing tin alloy treated in step 1 to 300°C, add sawdust whose mass is 5 times the silver in the crude zinc, stir well, remove the slag, repeat the operation, and observe that the floating matter is black carbon particles, stop removing the slag operation, and finally obtain liquid tin with low silver content and silver-zinc shell containing carbon particles, and the liquid tin can be desilvered tin after cooling.

[0027] Wherein the silver-zinc shell in step 2 is ...

Embodiment 3

[0030] Such as figure 1 Shown, this adds sawdust to the method for removing silver in silver-containing tin alloy, and its concrete steps are as follows:

[0031] Step 1. First, heat up 10 tons of silver-containing tin alloy (the silver content in the silver-containing tin alloy is 25000g / t, and the rest is tin) to 550°C and fully melt it, and mix it according to the molar ratio of silver in the silver-containing tin alloy to zinc in the crude zinc: 1 : 9 add thick zinc, fully stir and dissolve;

[0032] Step 2. Cool the silver-containing tin alloy treated in step 1 to 380°C, add wood chips whose mass is 5 times the silver in the crude zinc, stir well, remove the slag, repeat the operation, and observe that the floating matter is black carbon particles, stop removing the slag operation, and finally obtain liquid tin with low silver content and silver-zinc shell containing carbon particles, and the liquid tin can be desilvered tin after cooling.

[0033] Wherein the silver-zi...

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