Method for preparing high-purity indium

Patent metadata

Field	Value
Publication number	US-2025075289-A1
Application number	US-202418805621-A
Country	US
Kind code	A1
Filing date	Aug 15, 2024
Priority date	Aug 29, 2023
Publication date	Mar 6, 2025
Grant date	—

Abstract

Provided is a method for preparing high-purity indium (In). The method for preparing the high-purity In includes: distilling refined In to obtain an In vapor-containing gas; and condensing the In vapor-containing gas to obtain the high-purity In; where the distilling is conducted at a temperature of 1,000° C. to 1,100° C. under a vacuum degree of 1.0×10−3 Pa to 5.0×10−2 Pa; and the condensing is conducted at a temperature of 700° C. to 900° C. under a vacuum degree of 1.0×10−3 Pa to 5.0×10−2 Pa. The In vapor-containing gas is obtained by controlling the temperature and vacuum degree of the distilling to evaporate In and impurities with a vapor pressure higher than the In. The temperature and vacuum degree of the condensing are adjusted to condense the In in the In vapor-containing gas.

First claim

What is claimed is:

1 . A method for preparing high-purity indium (In), comprising the following steps:
distilling refined In to obtain an In vapor-containing gas; and condensing the In vapor-containing gas to obtain the high-purity In, wherein the distilling is conducted at a temperature of 1,000° C. to 1,100° C. under a vacuum degree of 1.0×10 −3 Pa to 5.0×10 −2 Pa, and the condensing is conducted at a temperature of 700° C. to 900° C. under a vacuum degree of 1.0×10 −3 Pa to 5.0×10 −2 Pa.

2 . The method according to claim 1 , wherein the refined In has a purity of greater than 99.990%; and the refined In comprises a high vapor pressure element and a low vapor pressure element, the high vapor pressure element comprising In and one or more selected from the group consisting of Pb, Bi, Cd, Mg, Tl, Zn, As, and S, and the low vapor pressure element comprising one or more selected from the group consisting of Sn, Ag, Cu, Fe, Ni, Al, and Si.

3 . The method of claim 1 , wherein the distilling is conducted for 1 h to 8 h, and the condensing is conducted for 1 h to 8 h.

4 . The method of claim 1 , wherein the method is conducted in a vacuum distillation apparatus, and the vacuum distillation apparatus is controlled by an intelligent control system, wherein the intelligent control system has proportional-integral-derivative (PID) regulating and auto-tuning functions, the vacuum distillation apparatus comprising:
a vacuum pump; a molecular pump connected to a cooling water machine and the vacuum pump separately; a high-vacuum corrugated tube connected to the molecular pump, wherein a baffle valve and a seal are arranged between the molecular pump and the high-vacuum corrugated tube, the baffle valve is arranged at an outlet of the molecular pump, and the seal is configured to seal the baffle valve and the high-vacuum corrugated tube; an ionization gauge, a resistance gauge, and a bleed valve that are arranged on the high-vacuum corrugated tube; a furnace tube connected to the high-vacuum corrugated tube through a water-cooling flange; a heating furnace body traversed by the furnace tube, wherein the heating furnace body comprises a furnace shell and a furnace cavity surrounded by the furnace shell, and the furnace shell is provided with a molecular pump controller and a composite vacuum gauge; and a pressure regulating valve connected to an end of the furnace tube close to the pressure regulating valve through a pipeline; wherein a vacuum pressure gauge is arranged on the pipeline; the furnace cavity is provided with a furnace mouth for passage of the furnace tube; and the furnace cavity is divided into a first constant temperature zone, a second constant temperature zone, a third constant temperature zone, a fourth constant temperature zone, and a fifth constant temperature zone along a direction in which the furnace tube passes through the furnace mouth, and an independent temperature measurer is arranged in each of the first to fifth constant temperature zones; and the first to fifth constant temperature zones are independently a cavity surrounded by a thermal insulation material.

5 . The method of claim 4 , wherein the furnace tube is a quartz tube; and the furnace tube has an outer diameter of 60 mm and a wall thickness of 5 mm.

6 . The method of claim 4 , wherein a heating element of the heating furnace body is a siliconit; and the thermal insulation material is composed of three layers of alumina ceramic fiber board.

7 . The method of claim 4 , wherein the furnace shell is a double-layer furnace shell, and an air cooling system is arranged between the double-layer furnace shell.

8 . The method of claim 4 , wherein the first to fifth constant temperature zones have lengths of 200 mm, 200 mm, 200 mm, 180 mm, and 180 mm, respectively; the first to fifth constant temperature zones have widths of 60 mm, 60 mm, 60 mm, 50 mm, and 50 mm, respectively; and two adjacent constant temperature zones are spaced apart by 50 mm.

9 . The method of claim 4 , wherein the refined In has a purity of greater than 99.990%; and the refined In comprises a high vapor pressure element and a low vapor pressure element, the high vapor pressure element comprising In and one or more selected from the group consisting of Pb, Bi, Cd, Mg, Tl, Zn, As, and S, and the low vapor pressure element comprising one or more selected from the group consisting of Sn, Ag, Cu, Fe, Ni, Al, and Si.

10 . The method of claim 4 , wherein the distilling is conducted for 1 h to 8 h, and the condensing is conducted for 1 h to 8 h.

Assignees

• Univ Kunming Science & Technology

Inventors

• Kong Lingxin
• Pang Jian
• Yang Bin
• Xu Baoqiang
• Jiang Wenlong
• Xu Junjie
• Liu Dachun
• Tian Yang
• Deng Yong

Classifications

• C22B9/04

  Refining by applying a vacuum · CPC title

• B01D5/0045

  Vacuum condensation · CPC title

• B01D5/006

  with evaporation or distillation · CPC title

• C22B9/02

  Refining by liquating, filtering, centrifuging, distilling, or supersonic wave action {including acoustic waves; (C22B9/003, C22B9/006, C22B9/05, C22B9/22 take precedence)} · CPC title

• C22B58/00 Primary

  Obtaining gallium or indium {(treatment or purification of solutions by liquid-liquid extraction, by ion-exchange or by adsorption C22B3/20)} · CPC title