CN110964912A

CN110964912A - Method for recovering and purifying platinum from platinum-tungsten alloy

Info

Publication number: CN110964912A
Application number: CN201911323759.2A
Authority: CN
Inventors: 侯智超; 陈斐; 罗瑶; 贺昕; 王鹏; 关俊卿; 马贤杰; 李治宇
Original assignee: Grikin Advanced Material Co Ltd
Current assignee: Grikin Advanced Material Co Ltd
Priority date: 2019-12-20
Filing date: 2019-12-20
Publication date: 2020-04-07

Abstract

The invention discloses a method for recovering and purifying platinum from platinum-tungsten alloy, which adopts a physical crushing process and a wet recovery and purification process to realize rapid recovery and purification of platinum-tungsten alloy, shortens the recovery and purification period and obtains spongy platinum. The physical crushing process crushes the platinum-tungsten alloy into 50-100 meshes, the purity of the spongy platinum is more than 99.9%, and the recovery and purification rate is more than 98%.

Description

Method for recovering and purifying platinum from platinum-tungsten alloy

Technical Field

The invention belongs to the technical field of metallurgy, and relates to a method for recovering and purifying platinum from a platinum-tungsten alloy, in particular to a method for quickly purifying the platinum-tungsten alloy.

Background

The Pt-W alloy is an excellent noble metal strain material, has high tensile strength, resistivity and resistance strain sensitivity coefficient, has excellent corrosion resistance and oxidation resistance, and plays an important role in the fields of aerospace and the like. In addition, the platinum-tungsten alloy wire is an important material for preparing the medical spring ring at present by virtue of excellent mechanical property, low biological toxicity and good developing property.

In the medical field, the Pt-W alloy wire is a good spring coil material and a good developing material, and is mainly applied to the field of cardiovascular interventional medical treatment. China is the largest cardiovascular treatment apparatus potential market worldwide. In the future, with the increase of the number of patients with cardiovascular diseases, the need of interventional therapy will increase greatly, and the market scale of heart and large vessel interventional devices will also expand continuously. While the yield of medical instruments is rapidly increased, the demand of related key materials is also greatly increased, especially the demand of related developing materials and structural materials is rapidly increased in China, and domestic alternative imports have become a great trend.

Meanwhile, the platinum-tungsten alloy is an excellent noble metal strain material. Typical alloys are PtW8 and ptw9.5, which have high tensile strength, electrical resistivity, and resistance strain sensitivity, low temperature coefficient of resistance, and excellent oxidation resistance. The PtW9.5 strain wire is made into a resistance strain gauge, and a successful test is carried out on a rotating part of an aeroengine. The development of the Chinese aviation industry promotes the development and application of the platinum-tungsten alloy, PtW8, PtW8.5 and PtW9 alloys are successively produced in a trial mode, and novel high-temperature resistance strain alloys of Pt-W-Re-Ni and Pt-W-Re-Ni-Cr-Y are invented. The platinum-tungsten strain wire is used for manufacturing a static resistance strain gauge at 700 ℃, and the tungsten superfine wire (0.008mm) is used for a relaxation type miniature pressure sensor. The strongly hardened PtW4 alloy is used as a spark plug electrode and as a grid for radar power tubes. The PtW8 alloy is very wear resistant and low noise when used as a potentiometer winding. The Pt-W alloy wire has large annual market demand, and wastes and waste products generated in the using process have certain scale. As a noble metal product, how to realize the recycling of the noble metal has great economic benefits.

Disclosure of Invention

The invention adopts a physical crushing method, the platinum-tungsten alloy is crushed into particles with the particle size of about 50-100 meshes by a physical crusher, and the rapid recovery and purification of the platinum-tungsten alloy are realized by matching with a wet recovery process, so that the spongy platinum is obtained.

The method for recovering and purifying platinum from the platinum-tungsten alloy comprises the following steps of taking a certain amount of platinum-tungsten alloy, wherein the content of tungsten is less than 40%, crushing the raw material into 50-100-mesh particles through a physical crusher, mixing aqua regia and the platinum-tungsten alloy according to the mass ratio of 5:1, heating for 2-3 hours at the temperature of 80-100 ℃ until the platinum-tungsten alloy is completely dissolved, and filtering to obtain chloroplatinic acid solution. Adding ammonium chloride into the chloroplatinic acid solution, wherein the mass ratio of the ammonium chloride to the platinum is 2:3, uniformly mixing and stirring for 30 minutes, and filtering to obtain ammonium chloroplatinate precipitate. Dissolving the chloroplatinic acid ammonia precipitate in a hydrazine hydrate solution, wherein the mass ratio of hydrazine hydrate to platinum is 1:1, uniformly stirring for 30 minutes, and filtering to obtain a spongy platinum precipitate. Washing the spongy platinum filter residue for 3 times by using a dilute hydrochloric acid solution with the concentration of 1mol/L, then washing for 2 times by using deionized water to obtain the spongy platinum filter residue, drying the filter residue to obtain the spongy platinum with the purity of more than 99.9%, and recovering and purifying the spongy platinum with the purification rate of more than 98%.

The invention has the beneficial effects that:

(1) the specific surface area of the platinum-tungsten alloy is increased through a physical crushing process, the dissolution reaction speed is accelerated, and the rapid dissolution of the platinum-tungsten alloy is realized;

(2) by the wet recovery process, the recovery rate of the platinum is more than 98 percent, and the spongy platinum with the purity of more than 99.9 percent is obtained.

Drawings

FIG. 1 is a process flow diagram of the method for recovering and purifying platinum from a platinum-tungsten alloy.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

Example 1

100g of platinum-tungsten alloy with the tungsten content of 10 percent is taken, and the raw material is crushed into 100-mesh particles by a physical crusher. 500g of aqua regia and platinum-tungsten alloy are mixed, heated for 3 hours at the temperature of 80 ℃ until the platinum-tungsten alloy is completely dissolved, and filtered to obtain chloroplatinic acid solution. Adding 60g of ammonium chloride into the chloroplatinic acid solution, uniformly mixing and stirring for 30 minutes, and filtering to obtain ammonium chloroplatinate precipitate. Dissolving the chloroplatinic acid ammonia precipitate in 90g of hydrazine hydrate solution, uniformly stirring for 30 minutes, filtering to obtain spongy platinum precipitate, washing for three times by using hydrochloric acid solution with the concentration of 1mol/L, washing for two times by using deionized water, drying filter residues to obtain 88.2g of spongy platinum with the purity of 99.95%, and recovering and purifying the purity of 98%.

Example 2

500g of platinum-tungsten alloy with the tungsten content of 30 percent is taken, and the raw material is crushed into 80-mesh particles by a physical crusher. Mixing 2500g of aqua regia and platinum-tungsten alloy, heating for 3 hours at the temperature of 90 ℃ until the platinum-tungsten alloy is completely dissolved, and filtering to obtain chloroplatinic acid solution. 233.3g of ammonium chloride is added into the chloroplatinic acid solution, the mixture is uniformly mixed and stirred for 30 minutes, and ammonium chloroplatinate precipitate is obtained after filtration. Dissolving the chloroplatinic acid ammonia precipitate in 350g of hydrazine hydrate solution, uniformly stirring for 30 minutes, filtering to obtain spongy platinum precipitate, washing for three times by using hydrochloric acid solution with the concentration of 1mol/L, washing for two times by using deionized water, drying filter residues to obtain 344.75g of spongy platinum with the purity of 99.93%, and recovering and purifying the purity of 98.5%.

The above embodiments describe the technical solutions of the present invention in detail. It will be clear that the invention is not limited to the described embodiments. Based on the embodiments of the present invention, those skilled in the art can make various changes, but any changes equivalent or similar to the present invention are within the protection scope of the present invention.

Claims

1. A method for recovering and purifying platinum from a platinum-tungsten alloy comprises the following steps: the method is characterized by comprising a physical crushing process and a wet recovery and purification process; the physical crushing process crushes the platinum-tungsten alloy into 50-100 meshes, and the wet recovery and purification process obtains the spongy platinum.

2. The method of claim 1, wherein the platinum-tungsten alloy has a tungsten content of less than 40%.

3. The method of claim 1, wherein the wet recovery purification process comprises the steps of:

1) dissolving the crushed platinum-tungsten alloy by aqua regia to obtain chloroplatinic acid solution;

2) adding ammonium chloride into the chloroplatinic acid solution obtained in the step 1), and mixing and stirring;

3) filtering the solution obtained in the step 2) to obtain ammonium chloroplatinate precipitate;

4) dissolving the precipitate obtained in the step 3) in a hydrazine hydrate solution, stirring, and filtering to obtain a spongy platinum precipitate;

5) and 4) washing and drying the spongy platinum precipitate obtained in the step 4) to obtain spongy platinum.

4. The method of claim 3, wherein the mass ratio of aqua regia to platinum-tungsten alloy in step 1) is 5: 1.

5. The method of claim 3, wherein the dissolving in step 1) is heated at 80-100 ℃ for 2-3 hours.

6. The method of claim 3, wherein the mass ratio of ammonia chloride to platinum in step 2) is 2:3, and the mixing is performed for 30 minutes.

7. The method according to claim 3, wherein the mass ratio of hydrazine hydrate to platinum in the step 4) is 1:1, the stirring time is 30 minutes, and sponge platinum filter residue precipitate is obtained after filtering.

8. The method as claimed in claim 3, wherein the washing in step 5) is performed 3 times with a dilute hydrochloric acid solution having a concentration of 1mol/L and two times with deionized water.

9. The method of claim 3, wherein the purity of the spongy platinum in step 5) is greater than 99.9%, and the recovery and purification rate is greater than 98%.