Agent for selective antimony and arsenic removal and tin retaining for refining secondary crude lead, and use method thereof

Abstract

An agent for selective antimony and arsenic removal and tin retaining includes 10-30 wt % of aluminum, 65-85 wt % of calcium, 1-10 wt % of coke powder, and 1-5 wt % of lead powder. According to the content of antimony in lead, the antimony and arsenic removal and tin retaining agent is added to a molten lead which is at a temperature of about 550-650° C. at a certain proportion so as to carry out an antimony and arsenic removal reaction; after the reaction is completed, cooling is carried out, and antimony and arsenic scum is fished out to obtain a molten lead with antimony and arsenic removed; the content of antimony and arsenic is reduced to 0.0005 wt % or less, and the content of tin is substantially unchanged. The production costs for lead alloy preparation are reduced, and no smoke and odor appear in an antimony and arsenic removal reaction process.

Claims

1. A selective antimony and arsenic removal and tin retaining agent for refining secondary crude lead, wherein the selective antimony and arsenic removal and tin retaining agent, in a mass percentage, consists of: 10-30 wt % of aluminum, 65-85 wt % of calcium, 1-10 wt % of coke powder, and 1-2 wt % of lead powder, based on a total mass of the antimony and arsenic removal and tin retaining agent of 100, wherein the calcium, the aluminum, the coke powder, and the lead powder are thoroughly mixed at the mass percentage to produce the selective antimony and arsenic removal and tin retaining agent.

2. A method of using the selective antimony and arsenic removal and tin retaining agent for refining secondary crude lead according to claim 1, wherein the selective antimony and arsenic removal and tin retaining agent is used for refinement and antimony and arsenic removal production of primary lead and secondary crude lead; and the method comprises the following steps: Step (1): weighing the calcium, the aluminum, the coke powder, and the lead powder according to the mass percentage, and uniformly mixing the calcium, the aluminum, the coke powder, and the lead powder to form the selective antimony and arsenic removal and tin retaining agent; Step (2): taking a sample from a secondary crude lead and subjecting the sample to a spectral analysis to determine a total content of antimony and arsenic in a refining pot, followed by heating up the sample to 580-650° C. to obtain a molten compound, and then adding the selective antimony and arsenic removal and tin retaining agent into the refining pot, wherein an adding amount of the selective antimony and arsenic removal and tin retaining agent is 1-1.5 times more than the total content of the antimony and the arsenic; turning on a stirrer to stir the molten compound to generate a vortex, allowing the selective antimony and arsenic removal and tin retaining agent to melt into the molten compound and combine with the antimony and the arsenic to form an antimonide, wherein the antimonide floats on the surface of the molten compound, and further stirring the molten compound for 10-60 min after adding the selective antimony and arsenic removal and tin retaining agent; and Step (3): allowing the molten compound to stand and cool down to reduce a temperature of the molten compound to 480° C. or lower, and adding a slagging agent or sawdust to the molten compound to form a paste slag, followed by stirring to remove the remaining calcium and aluminum until the paste slag becomes a black powder slag, and removing the black powder slag, so that the total content of the antimony and the arsenic in the molten compound is reduced to 0.0005% or less.

Description

DETAILED DESCRIPTION OF THE EMBODIMENTS

(1) The agent for antimony and arsenic removal and tin retaining of the present invention consists of 10-30 wt % of aluminum, 65-85 wt % of calcium, 1-10 wt % of coke powder, and 1-2 wt % of lead powder, based on the total mass of the agent for antimony and arsenic removal and tin retaining of 100, where the calcium, aluminum, coke powder, and lead powder are thoroughly mixed in the above mass ratio, to produce the antimony and arsenic removal and tin retaining agent.

(2) As a first preferred alternative, the agent for selective antimony and arsenic removal and tin retaining consists of 10 wt % of the aluminum, 80 wt % of the calcium, 8 wt % of the coke powder, and 2 wt % of the lead powder, based on the total mass of the agent for selective antimony and arsenic removal and tin retaining of 100.

(3) As a second preferred alternative, the agent for selective antimony and arsenic removal and tin retaining consists of 25 wt % of the aluminum, 72 wt % of the calcium, 2 wt % of the coke powder, and 1 wt % of the lead powder, based on the total mass of the agent for selective antimony and arsenic removal and tin retaining of 100.

(4) As a third preferred alternative, the agent for selective antimony and arsenic removal and tin retaining consists of 30 wt % of the aluminum, 67 wt % of the calcium, 2 wt % of the coke powder, and 1 wt % of the lead powder, based on the total mass of the agent for selective antimony and arsenic removal and tin retaining of 100.

(5) The agent for selective antimony and arsenic removal and tin retaining of the present invention is used for refinement and antimony and arsenic removal production of primary lead and secondary crude lead.

(6) A use method of employing the above agent for selective antimony and arsenic removal and tin retaining for refining secondary crude lead to remove antimony and arsenic from the crude lead includes the following steps:

(7) Step (1): weighing each of the components in the mass ratio, and uniformly mixing the components to form an antimony and arsenic removal composition;

(8) Step (2): taking a sample and subjecting the sample to a spectral analysis to obtain a total content of the antimony and arsenic in a refining pot, followed by heating up to 580-650° C., and then adding the antimony and arsenic removal and tin retaining agent into the refining pot in an amount which is 1-1.5 times more than the total content of the antimony and arsenic; turning on a stirrer to stir the molten lead to generate a vortex, wherein the antimony and arsenic removal and tin retaining agent is added at a speed which should not affect normal existence of the vortex, allowing the antimony and arsenic removal and tin retaining agent to quickly melt into the molten lead to combine with the antimony and arsenic to form an antimonide, which floats on a surface of the molten lead, and further stirring for 10-60 min after adding the antimony and arsenic removal and tin retaining agent; and

(9) Step (3): by allowing the molten lead to stand and cool down, reducing the temperature of the molten lead after reaction to 480° C. or lower, and adding coal powder or sawdust, followed by stirring to remove the remaining calcium and aluminum until a white pasty slag becomes a loose black powdery slag, and fishing out the slag, so that the antimony and arsenic in the molten lead are reduced to 0.0005% or less and tin content is substantially unchanged.

(10) The technical solutions of the present invention will be further explained below through examples.

(11) Example 1: the agent for selective antimony and arsenic removal and tin retaining consisted of 10 wt % of aluminum, 80 wt % of calcium, 8 wt % of coke powder, and 2 wt % of lead powder, based on the total mass of the agent for selective antimony and arsenic removal and tin retaining of 100.

(12) Secondary crude lead was weighed into a refining pot, heated for melting, and heated up to 500° C. A copper removal agent was used to remove copper, and the slag was fished out and then weighed. A sample was taken and subjected to direct-reading spectral analysis, revealing that it contained the following ingredients: Cu 0.0007%, Sb 0.25%, As 0.0051%, Sn 0.615%, Bi 0.003% and Ag 0.0008%. The molten lead was further heated up to 635° C., and the total content of antimony and arsenic in the pot was obtained. An antimony and arsenic removal composition was added in an amount which was 1.3 times more than the total content of antimony and arsenic. The composition contained the following ingredients: 10 wt % of Al, 80 wt % of Ca, 8 wt % of coke powder and 2 wt % of lead powder.

(13) The stirrer was turned on. The antimony and arsenic removal agent was added into the molten lead, and stirred continuously for 30 min. After that, the machine was turned off, and the molten lead was allowed to stand and cooled down to 480° C. Coal powder or sawdust was added and stirred to remove the remaining calcium and aluminum, until a white pasty slag became a loose black powdery slag. The ash slag was fished out. A sample was taken and subjected to direct-reading spectral analysis, revealing that it contained the following ingredients: Cu 0.0007%, Sb 0.0004%, As 0.0002%, Sn 0.601%, Bi 0.003% and Ag 0.0008%.

(14) Example 2: the agent for selective antimony and arsenic removal and tin retaining consisted of 25 wt % of aluminum, 72 wt % of calcium, 2 wt % of coke powder, and 1 wt % of lead powder, based on the total mass of the agent for selective antimony and arsenic removal and tin retaining of 100.

(15) Secondary crude lead was weighed into a refining pot, heated for melting, and heated up to 490° C. A copper removal agent was used to remove copper, and the ash slag was fished out and then weighed. A sample was taken and subjected to direct-reading spectral analysis, revealing that it contained the following ingredients: Cu 0.0005%, Sb 0.15%, As 0.0031%, Sn 0.517%, Bi 0.0026% and Ag 0.001%. The molten lead was further heated up to 605° C., and the total content of antimony and arsenic in the pot was obtained. An antimony and arsenic removal composition was added in an amount which was 1.2 times more than the total content of antimony and arsenic. The composition contained the following ingredients: 25 wt % of Al, 72 wt % of Ca, 2 wt % of coke powder and 1 wt % of lead powder.

(16) The stirrer was turned on. The antimony and arsenic removal agent was added into the molten lead, and stirred continuously for 35 min. After that, the machine was turned off, and the molten lead was allowed to stand and cooled down to 450° C. Coal powder or sawdust was added and stirred to remove the remaining calcium and aluminum, until a white pasty slag became a loose black powdery slag. The slag was fished out. A sample was taken and subjected to direct-reading spectral analysis, revealing that it contained the following ingredients: Cu 0.0005%, Sb 0.0003%, As 0.0002%, Sn 0.501%, Bi 0.0026% and Ag 0.00098%.

(17) Example 3: the agent for selective antimony and arsenic removal and tin retaining consisted of 30 wt % of aluminum, 67 wt % of calcium, 2 wt % of coke powder, and 1 wt % of lead powder, based on the total mass of the agent for selective antimony and arsenic removal and tin retaining of 100.

(18) Secondary crude lead was weighed into a refining pot, heated for melting, and heated up to 510° C. A copper removal agent was used to remove copper, and the ash slag was fished out and then weighed. A sample was taken and subjected to direct-reading spectral analysis, revealing that it contained the following ingredients: Cu 0.0003%, Sb 0.08%, As 0.0041%, Sn 0.685%, Bi 0.0027% and Ag 0.0007%. The molten lead was further heated up to 595° C., and the total content of antimony and arsenic in the pot was obtained. An antimony and arsenic removal composition was added in an amount which was 1.4 times more than the total content of antimony and arsenic. The composition contained the following ingredients: 30 wt % of Al, 67 wt % of Ca, 8 wt % of coke powder and 2 wt % of lead powder.

(19) The stirrer was turned on. The antimony and arsenic removal agent was added into the molten lead, and stirred continuously for 30 min. After that, the machine was turned off, and the molten lead was allowed to stand and cooled down to 480° C. Coal powder or sawdust was added and stirred to remove the remaining calcium and aluminum, until a white pasty slag became a loose black powdery slag. The slag was fished out. A sample was taken and subjected to direct-reading spectral analysis, revealing that it contained the following ingredients: Cu 0.0003%, Sb 0.0005%, As 0.0002%, Sn 0.661%, Bi 0.0028% and Ag 0.0007%.