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CN-121607639-B - Preparation process of high-purity zinc powder

CN121607639BCN 121607639 BCN121607639 BCN 121607639BCN-121607639-B

Abstract

The invention discloses a preparation process of high-purity zinc powder, and relates to the technical field of metal powder preparation. S1, raw material pretreatment, namely selecting industrial electrolytic zinc ingots with purity more than or equal to 99.95%, crushing into zinc particles with the diameter of 10-50 mm, removing surface oxide skin and oil dirt, cleaning, and removing ferromagnetic impurities through magnetic separation to obtain pretreated zinc raw materials. This kind of high-purity zinc powder preparation technology, when condensing high-purity zinc steam, through setting up a plurality of condensation module, can rotate the post through actuating mechanism drive and rotate the rotation with the condensation module, so reciprocally, can supply zinc steam in the condensation module in proper order and condense the powder process, and can arrange the powder at the in-process that rotates the rotation, realize continuous condensation powder process operation, need not to interrupt production flow, and, can avoid once only influencing the quality of powder process when letting in a large amount of steam, thereby can improve the efficiency and the quality of condensation, and then improve the efficiency and the quality of high-purity zinc powder preparation.

Inventors

  • CHEN HUILING
  • WANG ZHONGBING

Assignees

  • 福建中伟半导体材料有限公司

Dates

Publication Date
20260512
Application Date
20260202

Claims (9)

  1. 1. The preparation process of the high-purity zinc powder is characterized by comprising the following steps of: s1, raw material pretreatment, namely selecting industrial electrolytic zinc ingots with purity more than or equal to 99.95%, crushing into zinc particles with the diameter of 10-50 mm, removing surface oxide skin and oil dirt, and removing ferromagnetic impurities through magnetic separation to obtain pretreated zinc raw materials; S2, vacuum distillation and purification, namely feeding the pretreated zinc raw material into a vacuum distillation kettle, starting a vacuum system to enable the vacuum degree in the vacuum distillation kettle to be stable at 1-10 Pa, heating the vacuum distillation kettle to 900-1050 ℃, preserving heat for 2-4 hours to enable the zinc raw material to fully volatilize to form zinc vapor, grading and removing impurities through a multi-stage condensation baffle arranged in a distillation condensing device, capturing antimony trace impurities in a high-temperature region at 350-400 ℃, capturing high-purity zinc vapor in a medium-temperature region at 250-300 ℃, and capturing arsenic and cadmium vapor impurities in a low-temperature region; S3, condensing and pulverizing, namely introducing the high-purity zinc vapor collected in the step S2 into a condensing device for condensing to form zinc powder and collecting the zinc powder; s4, performing post-treatment, namely performing passivation treatment on the collected zinc powder under the protection of inert gas, and finally performing screening classification and vacuum sealing packaging to obtain high-purity zinc powder with the purity of more than or equal to 4N; The condensing device comprises a shell (1), a rotating column (10) rotating in the shell (1) and a driving mechanism driving the rotating column (10) to rotate, and further comprises a plurality of partition plates (11) connected with the rotating column (10) so that the partition plates (11) can slide on the inner wall of the shell (1), wherein a mounting cavity is formed between two adjacent partition plates (11) and the shell (1), and the condensing device further comprises a condensing module arranged in each mounting cavity; Each condensing module comprises a first sealing plate (1202) connected with the mounting cavity, a condensing cylinder (1201) rotationally connected with the first sealing plate (1202) and a first driving assembly for driving the condensing cylinder (1201) to rotate, wherein an upper cavity is formed between the top of the first sealing plate (1202) and the shell (1), the condensing module further comprises a filtering ring (1203) connected with a rotating column (10), a conical cover (1204) which is connected with the filtering ring (1203) and is arranged in a hollow way, and a plurality of rotating rings (1206) rotationally connected with the conical cover (1204), the filtering ring (1203) is rotationally connected with the bottom of the condensing cylinder (1201), the condensing module further comprises a plurality of condensing pipes (1205) communicated with the conical cover (1204) and a second driving assembly for driving the condensing pipes (1205) to rotate, the rotating ring (1206) is fixedly sleeved on the side wall of the condensing pipes (1205), the upper ends of the condensing pipes (1205) penetrate through the top of the condensing cylinders (1201) and are communicated with the upper cavity, the condensing module further comprises a plurality of rotating rings (1206) which are rotationally connected with the bottom of the condensing cylinders (1204), the cooling pipes (1201) are communicated with the bottom of the condensing cylinders (1201), and a plurality of cooling pipes (1205) are arranged in the cooling medium (1205) for cooling medium, and the cooling medium is further arranged in the cooling medium (120) and the cooling medium (120) is used for cooling medium (120) and cooling medium; zinc steam enters a condensation cylinder (1201) through an air inlet hole (1207) with a filter screen, the condensation cylinder (1201) revolves around a first sealing plate (1202) under the drive of a first driving component, a hollow conical cover (1204) is supported by a filtering ring (1203) connected with a rotary column (10), a second driving component is sleeved on a rotary ring (1206) on the side wall of the condensation cylinder (1205) to drive the condensation cylinder (1205) communicated with the conical cover (1204) to rotate, a liquid supply mechanism supplies low-temperature heat conduction oil into the condensation cylinder (1205), the low-temperature heat conduction oil flows into the condensation cylinder (1205) through the conical cover (1204), then flows into an upper cavity formed by the first sealing plate (1202) and a shell (1) through the upper end of the condensation cylinder (1205) penetrating through the top of the condensation cylinder (1201), zinc steam is condensed into zinc powder on the outer wall of the low-temperature condensation cylinder (1205), the zinc powder on the surface of the condensation cylinder (1205) is scraped to the filtering ring (1203) by a scraping mechanism, is ground, crushed, then discharged and collected, and rotated by the driving mechanism, so that a plurality of condensation modules are sequentially switched, and continuous scraping, condensing, crushing, collecting and air inlet stations are realized.
  2. 2. The process for preparing the high-purity zinc powder according to claim 1 is characterized in that the liquid supply mechanism comprises a liquid supply cavity (201) arranged in a rotating column (10), a liquid supply pipe (202) communicated with the liquid supply cavity (201) and a first communication pipe (203) communicated with a conical cover (1204) and the liquid supply cavity (201), the liquid supply mechanism further comprises a liquid outlet cavity (206) arranged in the rotating column (10), a liquid outlet pipe (208) communicated with the liquid outlet cavity (206) and a communication hole (207) communicated with an upper cavity and the liquid outlet cavity (206), the liquid supply pipe (202) is in rotating fit connection with the bottom of the rotating column (10), and the liquid outlet pipe (208) is in rotating fit connection with the top of the rotating column (10).
  3. 3. The process for preparing the high-purity zinc powder according to claim 1, wherein the first driving assembly comprises a circular cover (401) connected with a condensing cylinder (1201), a plurality of groups of liquid outlet holes (402) communicated with the circular cover (401) and a plurality of blades (403) connected with the circular cover (401), and the circular cover (401) is arranged in an upper chamber and communicated with a condensing pipe (1205).
  4. 4. The process for preparing the high-purity zinc powder according to claim 1, wherein the second driving assembly comprises a circular groove (301) formed in the top of a circular cover (401), concentric rings (302) rotating in the circular groove (301) and a second sealing plate (303) connected between the concentric rings (302) and a rotating column (10), and further comprises a rubber wheel (304) connected with a condensing tube (1205) so that the rubber wheel (304) can roll on the side wall of the concentric rings (302).
  5. 5. The process for preparing the high-purity zinc powder according to claim 1, wherein the scraping mechanism comprises a conical ring (501) sleeved on the side wall of the condensation pipe (1205), a rotating rod (502) connected with the conical ring (501) and a cylinder (503) connected between the rotating rod (502) and the second sealing plate (303), and the cylinder (503) is positioned above the second sealing plate (303).
  6. 6. The process for preparing the high-purity zinc powder according to claim 1, wherein the condensing device further comprises a feed valve (604) communicated with the shell (1), an annular cover (601) connected with the condensing cylinder (1201) and a second communicating pipe (603) communicated with the annular cover (601), the second communicating pipe (603) can be communicated with the feed valve (604), and the air inlet hole (1207) is communicated with the annular cover (601).
  7. 7. The process for preparing the high-purity zinc powder is characterized in that the condensing module further comprises a recycling mechanism for recycling inert gas in the condensing cylinder (1201), the recycling mechanism comprises a gas storage tank (701) connected with the shell (1), a fan (702) communicated with the gas storage tank (701) and an air pipe (703) communicated with the fan (702) and the shell (1), and the recycling mechanism further comprises a first electromagnetic valve (704) communicated with the air pipe (703).
  8. 8. The process for preparing the high-purity zinc powder according to claim 1, wherein the condensing device further comprises a collecting mechanism for collecting the zinc powder discharged by the filtering ring (1203), and the collecting mechanism comprises a collecting box (803), a collecting cover (801) communicated with the bottom of the shell (1) and a second electromagnetic valve (802) communicated with the collecting cover (801) and the collecting box (803).
  9. 9. The process for preparing the high-purity zinc powder according to claim 1 is characterized in that the driving mechanism comprises a gear ring (901) connected with the rotary column (10), a gear (904) meshed with the gear ring (901) and a motor (903) connected with the gear (904), and the driving mechanism further comprises a bracket (902) connected between the motor (903) and the shell (1).

Description

Preparation process of high-purity zinc powder Technical Field The invention relates to the technical field of metal powder preparation, in particular to a preparation process of high-purity zinc powder. Background Zinc powder is an important industrial raw material, has great market demand, is widely applied to the fields of metallurgy, chemical industry, construction, transportation, medicine, electronics and the like, and is one of production methods of high-purity zinc powder by an evaporation condensation method. However, when the existing condensing device is used, a large amount of zinc vapor needs to be introduced once in a single cycle, and at the moment, the problem that the concentration of local zinc vapor is too high easily occurs in a condensing chamber is solved, on one hand, high concentration steam can cause rapid thickening of a zinc powder layer on the surface of a condensing wall, thermal resistance is increased, the condensing speed of subsequent steam is reduced, on the other hand, the condensing chamber is mainly operated intermittently, a condensing product needs to be cleaned after a period of condensing time, the production flow is interrupted, and energy waste is caused due to frequent start and stop, so that the condensing efficiency and quality are influenced, and the high-purity zinc powder preparation efficiency and quality are further improved. Disclosure of Invention The invention aims to provide a preparation process of high-purity zinc powder, which aims to solve the problems in the prior art. In order to achieve the purpose, the invention provides the following technical scheme that the preparation process of the high-purity zinc powder comprises the following steps: s1, raw material pretreatment, namely selecting industrial electrolytic zinc ingots with purity more than or equal to 99.95%, crushing into zinc particles with the diameter of 10-50 mm, removing surface oxide skin and oil dirt, and removing ferromagnetic impurities through magnetic separation to obtain pretreated zinc raw materials; S2, vacuum distillation and purification, namely feeding the pretreated zinc raw material into a vacuum distillation kettle, starting a vacuum system to enable the vacuum degree in the vacuum distillation kettle to be stable at 1-10 Pa, heating the vacuum distillation kettle to 900-1050 ℃, preserving heat for 2-4 hours to enable the zinc raw material to fully volatilize to form zinc vapor, grading and removing impurities through a multi-stage condensation baffle arranged in a distillation condensing device, capturing antimony trace impurities in a high-temperature region at 350-400 ℃, capturing high-purity zinc vapor in a medium-temperature region at 250-300 ℃, and capturing arsenic and cadmium vapor impurities in a low-temperature region; S3, condensing and pulverizing, namely introducing the high-purity zinc vapor collected in the step S2 into a condensing device for condensing to form zinc powder and collecting the zinc powder; s4, performing post-treatment, namely performing passivation treatment on the collected zinc powder under the protection of inert gas, and finally performing screening classification and vacuum sealing packaging to obtain high-purity zinc powder with the purity of more than or equal to 4N; The condensing device comprises a shell, a rotating column rotating in the shell, a driving mechanism driving the rotating column to rotate, a plurality of partition boards connected with the rotating column, a mounting cavity formed between two adjacent partition boards and the shell, and a condensing module arranged in each mounting cavity. Preferably, each condensing module comprises a first sealing plate connected with the installation cavity, a condensing cylinder rotationally connected with the first sealing plate, a first driving assembly for driving the condensing cylinder to rotate, an upper cavity is formed between the top of the first sealing plate and the shell, the condensing module further comprises a filtering ring connected with the rotating column, a conical cover which is connected with the filtering ring and is arranged in a hollow mode, a plurality of rotating rings rotationally connected with the conical cover, the filtering ring is rotationally connected with the bottom of the condensing cylinder, the condensing module further comprises a plurality of condensing pipes communicated with the conical cover and a second driving assembly for driving the condensing pipes to rotate, the rotating rings are fixedly sleeved on the side walls of the condensing pipes, the upper ends of the condensing pipes penetrate through the top of the condensing cylinders and are communicated with the upper cavity, the condensing module further comprises an air inlet hole communicated with the condensing cylinders and a filter screen arranged in the air inlet hole, and further comprises a liquid supply mechanism for supplying low-temperature heat conducting oil into the c