Method for producing high-purity silver powder by using silver-containing dead catalyst

A waste catalyst and high-purity technology, applied in the direction of improving process efficiency, can solve the problems of high energy consumption, easy entry of silver into the slag phase, low purity, activity and dispersion of silver powder, and achieve the effect of overcoming single performance

Inactive Publication Date: 2013-05-01
HOOTECH
View PDF2 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] At present, the method of recovering silver from silver-containing waste catalysts at home and abroad is that the silver-containing waste catalysts with aluminum oxide and silicon dioxide as the carrier are mostly directly smelted by fire method to obtain crude silver, and then electrolyzed by traditional electrolytic cells. Refining can obtain silver powder; or use nitric acid as leaching agent to obtain silver nitrate solution, and then carry out traditional electrolytic refining to obtain silver powder. Electrolytic refining has some disadvantages, such as high energy consumption, high production cost, and silver is easy to enter the slag phase; electrolysis will produce A large amount of acid mist is easy to corrode equipment and has a great impact on the working environment of the factory: electrolysis will produce anode slime, which needs to be further processed, which increases the process; the waste gas, waste water and waste residue produced are difficult to process, resulting in a decrease in the recovery rate of silver
Moreover, the silver powder prepared by the traditional method has low purity, activity and dispersion, and has single performance.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for producing high-purity silver powder by using silver-containing dead catalyst

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0033] (1) Use 500 grams of silver-containing waste catalyst as raw material, and use 1500 mL of 10% to 30% dilute nitric acid solution to dissolve silver into silver nitrate solution;

[0034] (2) Add 47 grams of precipitating agent to the filtered silver nitrate solution to generate silver-containing compound precipitation;

[0035] (3) The silver-containing compound precipitate is filtered, washed, and then slurried to obtain the slurried silver-containing compound;

[0036] (4) Select hydrogen peroxide and sodium borohydride as the reducing agent, polyvinylpyrrolidone as the protective agent, the amount of the protective agent added is 3% of the silver content, and the pH value is controlled at the same time, the reducing agent is added at a speed of 10mL / min, and the stirring speed is 220rpm , the reaction temperature is 55 ° C, under the condition of ultrasonic vibration, silver ions can be reduced to spherical high-purity silver powder particles.

[0037] (5) The obtai...

example 2

[0039] (1) Use 500 grams of silver-containing waste catalyst as raw material, and use 1500 mL of 10% to 30% dilute nitric acid solution to dissolve silver into silver nitrate solution;

[0040] (2) Add 45 grams of precipitating agent to the filtered silver nitrate solution to generate silver-containing compound precipitation;

[0041] (3) The silver-containing compound precipitate is filtered, washed, and then slurried to obtain the slurried silver-containing compound;

[0042] (4) Select formic acid as the reducing agent, polyethylene glycol as the protective agent, the amount of the protective agent added is 3% of the silver content, the pH value is controlled to be 3, the adding speed of the reducing agent is 30mL / min, the stirring speed is 350rpm, and the reaction The temperature is 45°C, and under the condition of ultrasonic vibration, silver ions can be reduced to flake high-purity silver powder particles.

[0043] (5) The obtained high-purity silver powder is filtered,...

example 3

[0045] (1) Use 500 grams of silver-containing waste catalyst as raw material, and use 1500 mL of 10% to 30% dilute nitric acid solution to dissolve silver into silver nitrate solution;

[0046] (2) Add 45 grams of precipitating agent to the filtered silver nitrate solution to generate silver-containing compound precipitation;

[0047] (3) The silver-containing compound precipitate is filtered, washed, and then slurried to obtain the slurried silver-containing compound;

[0048] (4) Select aliphatic aldehyde as the reducing agent, sodium lauryl sulfate as the protective agent, the amount of the protective agent added is 3% of the silver content, the pH value is controlled to be 13, the adding speed of the reducing agent is 45mL / min, and the stirring speed is 400rpm , the reaction temperature is 45 ° C, under the condition of ultrasonic vibration, silver ions can be reduced to reticular high-purity silver powder particles.

[0049] (5) The obtained high-purity silver powder is ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for producing high-purity silver powder by using a silver-containing dead catalyst, and belongs to the technical field of noble metal refining. The method comprises the following steps: the silver-containing dead catalyst is used as a raw material, silver is dissolved and converted to silver nitrate solution by dilute nitric acid; a precipitant is added in the silver nitrate solution after the filtration; a silver-containing compound precipitate is pulped after being filtered and washed; one or two reagents are randomly chosen from hydrazine hydrate, hydrogen peroxide, sodium borohydride, formic acid, ascorbic acid, glucose, fatty aldehyde, fatty amine and formaldehyde as reducing agent; any one reagent is chosen from polyvinylpyrrolidone, cetyl trimethyl ammonium bromide, lauryl sodium sulfate, polyethylene glycol and between as a protective agent; silver ions are reduced to silver particles under the condition of ultrasonic oscillation; and the silver particles are precisely filtered, and are dried in vacuum to obtain the high-purity silver powder product. The method has the benefit that the high-purity silver powder product with high purity, high dispersity and high activity can be obtained, and has the advantages of stable product performance, high recovery rate and environmental friendliness.

Description

technical field [0001] The invention relates to a method for producing high-purity silver powder by using a silver-containing waste catalyst, and belongs to the technical field of precious metal refining. Background technique [0002] At present, the method of recovering silver from silver-containing waste catalysts at home and abroad is that the silver-containing waste catalysts with aluminum oxide and silicon dioxide as the carrier are mostly directly smelted by fire method to obtain crude silver, and then electrolyzed by traditional electrolytic cells. Refining can obtain silver powder; or use nitric acid as leaching agent to obtain silver nitrate solution, and then carry out traditional electrolytic refining to obtain silver powder. Electrolytic refining has some disadvantages, such as high energy consumption, high production cost, and silver is easy to enter the slag phase; electrolysis will produce A large amount of acid mist is easy to corrode equipment and has a grea...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C22B11/00C22B7/00
CPCY02P10/20
Inventor 王锐利郁丰善赵来运李富荣唐晓魏礼超索永喜
Owner HOOTECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap