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CN-121990578-A - Preparation method of high-purity quartz sand with aluminum doped surface

CN121990578ACN 121990578 ACN121990578 ACN 121990578ACN-121990578-A

Abstract

The invention relates to a preparation method of high-purity quartz sand doped with aluminum on the surface, which comprises the following steps of weighing an aluminum-containing medicament, dissolving the medicament with pure water, stirring the medicament to form an aluminum salt solution, weighing a certain amount of high-purity quartz sand, adding the aluminum salt solution according to the aluminum content of the quartz sand and the amount of aluminum elements to be doped, forming a turbid liquid, soaking the turbid liquid for 1-30 min, removing most of water through low-temperature drying, removing residual water through high-temperature drying, finally uniformly mixing the quartz sand doped with aluminum on the surface by a mixer, calcining the prepared high-purity quartz sand doped with aluminum on the surface in a high-temperature environment to obtain the high-purity quartz sand doped with aluminum on the surface, washing the high-purity quartz sand doped with aluminum on the surface by pure water, and drying and cooling the washed high-purity quartz sand doped with aluminum on the surface. And (3) preparing the high-purity quartz sand with the aluminum content of 10-16 ug/g by doping aluminum on the surface of the quartz sand.

Inventors

  • WEI YUANBAI
  • WEI LINZHI

Assignees

  • 江苏风日石英科技有限公司

Dates

Publication Date
20260508
Application Date
20251223

Claims (6)

  1. 1. The preparation method of the high-purity quartz sand with the aluminum doped on the surface is characterized by comprising the following steps of: firstly, preparing an aluminum salt solution, namely weighing an aluminum-containing medicament, dissolving the medicament with a corresponding amount of pure water, stirring the solution to form the aluminum salt solution, and placing the aluminum salt solution in a clean container; Weighing a certain amount of high-purity quartz sand, adding the aluminum salt solution prepared in the first step with a corresponding volume according to the aluminum content of the quartz sand and the amount of aluminum elements to be doped to form turbid liquid, soaking for 1-30 min, removing most of water through low-temperature drying, removing the residual water through high-temperature drying, and finally uniformly mixing by using a mixer to obtain the high-purity quartz sand with aluminum salt doped on the surface; third, calcining at high temperature, namely placing the high-purity quartz sand with the aluminum salt doped on the surface, which is prepared in the second step, in a high-temperature environment for calcining to obtain the high-purity quartz sand with the aluminum doped on the surface; and step four, cleaning and drying, namely washing the high-purity quartz sand with the aluminum doped surface obtained in the step three by pure water, and drying and cooling after washing.
  2. 2. The method for preparing high-purity quartz sand doped with aluminum on the surface according to claim 1, wherein the aluminum-containing agent is one or more of aluminum nitrate, aluminum sulfate octadecanoate, and aluminum ammonium sulfate.
  3. 3. The method for preparing high purity silica sand having an aluminum doped surface according to claim 1, wherein the pure water is pure water having a resistance value of more than 18 megaohms or distilled water subjected to distillation at least twice.
  4. 4. The method for preparing high-purity quartz sand doped with aluminum on the surface according to claim 1, wherein the low-temperature drying temperature is controlled to be 60-85 ℃.
  5. 5. The method for preparing the high-purity quartz sand doped with aluminum on the surface according to claim 1, wherein the high-temperature drying can be performed by adopting a contact type rotary electric furnace or non-contact type microwave drying, and the temperature of the drying by adopting the contact type rotary electric furnace is controlled to be 200-400 ℃.
  6. 6. The method for preparing the high-purity quartz sand doped with aluminum on the surface according to claim 1, wherein the high-temperature calcination is controlled to be at 700-1200 ℃ and the calcination time is 10-300 min.

Description

Preparation method of high-purity quartz sand with aluminum doped surface Technical Field The invention relates to a preparation method of high-purity quartz sand with aluminum doped on the surface. Background The Czochralski method is a large-area monocrystalline silicon preparation technology in China at present, wherein a quartz crucible is a key component of a photovoltaic monocrystalline furnace and is made of high-purity quartz sand, and is mainly used for containing molten silicon and manufacturing crystal bars required by subsequent procedures. Quartz crucibles have crystals (cristobalite) at high temperatures that tend to become silica, i.e. recrystallisation, also known as "devitrification" or "devitrification". This effect leads to the quartz crucible inlayer to be destroyed, and outer granule oxide gets into the silicon liquid, makes the silicon crystal structure variation of growing, can't normally grow brilliant, and crucible thickness attenuate with higher speed this moment, and then take place the deformation, leads to the crucible to scrap, can't reuse, is the key consumptive material of crystal pulling. With the increase of the size of the quartz crucible, new requirements are put forward on the quality of high-purity quartz sand, and the strength of the quartz crucible can be enhanced by a proper amount of aluminum element because the aluminum-oxygen bond energy is higher than the silicon-oxygen bond energy. In production practice, the purity and inclusion content of some high-quality high-purity quartz sand can reach or exceed the standards of high-purity quartz sand for quartz crucibles, but the aluminum content of part of high-purity quartz sand is even less than 10ug/g due to the excessive purity, the prepared quartz crucible is relatively easy to soften at high temperature, and trace aluminum elements are required to be doped on the surface of the quartz crucible, so that the strength of the quartz crucible is improved. Disclosure of Invention In order to solve the problems, the invention provides a preparation method of high-purity quartz sand with aluminum doped on the surface, which is used for carrying out surface doping on the quartz sand with aluminum content lower than 10ug/g to prepare the high-purity quartz sand with aluminum content between 10ug/g and 16 ug/g. The technical scheme adopted by the invention is as follows: The preparation method of the high-purity quartz sand with the aluminum doped on the surface comprises the following steps: firstly, preparing an aluminum salt solution, namely weighing an aluminum-containing medicament, dissolving the medicament with a corresponding amount of pure water, stirring the solution to form the aluminum salt solution, and placing the aluminum salt solution in a clean container; Weighing a certain amount of high-purity quartz sand, adding the aluminum salt solution prepared in the first step with a corresponding volume according to the aluminum content of the quartz sand and the amount of aluminum elements to be doped to form turbid liquid, soaking for 1-30 min, removing most of water through low-temperature drying, removing the residual water through high-temperature drying, and finally uniformly mixing by using a mixer to obtain the high-purity quartz sand with aluminum salt doped on the surface; third, calcining at high temperature, namely placing the high-purity quartz sand with the aluminum salt doped on the surface, which is prepared in the second step, in a high-temperature environment for calcining to obtain the high-purity quartz sand with the aluminum doped on the surface; and step four, cleaning and drying, namely washing the high-purity quartz sand with the aluminum doped surface obtained in the step three by pure water, and drying and cooling after washing. As a further improvement of the technical scheme, the aluminum-containing medicament is one or more of aluminum nitrate, aluminum sulfate octadecanoate and aluminum ammonium sulfate. As a further improvement of the above technical scheme, the pure water is pure water with a resistance value of more than 18 megaohms or distilled water subjected to at least two distillations. As a further improvement of the technical scheme, the temperature of the low-temperature drying is controlled to be 60-85 ℃. As a further improvement of the technical scheme, the high-temperature drying can be performed by adopting a contact type rotary electric furnace or non-contact type microwave drying, and the temperature of the drying by adopting the contact type rotary electric furnace is controlled to be 200-400 ℃. As a further improvement of the technical scheme, the calcination temperature of the high-temperature calcination is controlled to be 700-1200 ℃ and the calcination time is 10-300 min. The invention has the advantages that: The invention adopts pure water to dissolve the medicament for quartz sand doping, can avoid the pollution of high-purity quartz sand, is dried in a rotary