Method for separating and refining iron and chromium from polymetallic hazardous waste

A hazardous waste and polymetallic technology, applied in the direction of non-metallic elements, chemical instruments and methods, phosphorus compounds, etc., can solve the problems of increasing the cost of hazardous waste disposal, limited service life, high energy consumption of electrolysis, etc., to save processing time, Reduced processing costs and high economic value

Active Publication Date: 2017-11-07
青川县天运金属开发有限公司
View PDF5 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The electrolysis method has high energy consumption and complex equipment, which increases the disposal cost of hazardous waste
In

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 separating and refining iron and chromium from polymetallic hazardous waste
  • Method for separating and refining iron and chromium from polymetallic hazardous waste
  • Method for separating and refining iron and chromium from polymetallic hazardous waste

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0052] A method for separating refined iron and chromium from polymetallic hazardous waste (phosphate-free sludge)

[0053] (1) Raw material analysis

[0054] Take comprehensive sludge without phosphate radicals, add Fe salt to the sludge and mix evenly to make Fe:Cr=2.5~3.5:1, analyze its metal content with flame atomic absorption spectrophotometer, the results are shown in Table 1.

[0055] Table 1 Contents of metal components in comprehensive sludge

[0056] .

[0057] (2) Acid leaching experiment

[0058] Take 500g of the above-mentioned mixed comprehensive sludge into a 2000mL beaker, add 1200mL of water, put mechanical stirring into the beaker, adjust the rotation speed to 300 r / min to make the sludge slurry, and then slowly add 98% sulfuric acid to the slurry, and the sludge in the process The mud gradually dissolves, add sulfuric acid until the sludge no longer reacts, continue to stir for 30 min, and keep the pH value at about 0.5 to completely leach the metals i...

Embodiment 2

[0073] A method for separating refined iron and chromium from polymetallic hazardous waste (adding phosphate to phosphate-free sludge to separate iron and chromium)

[0074] (1) Preparation of iron and chromium filtrate

[0075] Get 500g of sludge prepared in Example 1, add 1000mL of water to make slurry, carry out acid leaching, crude ferrochrome, and coarse ferrochrome dissolving operations according to the method in Example 1, finally obtain 816mL of filtrate, and use flame The concentration of metals in the filtrate was measured by an atomic absorption spectrophotometer, and the results are shown in Table 4.

[0076] Table 4 Composition list of filtrate containing iron and chromium

[0077] .

[0078] (2) Add phosphate to produce iron phosphate

[0079] Get 5 parts of 150mL above-mentioned iron, chromium filtrate (Fe 3+ : 11.05g / L, Cr 3+ : 4.48g / L, the concentration ratio of iron and chromium is 2.47), respectively placed in 500mL beakers, and 85% phosphoric acid ...

Embodiment 3

[0083] A method for separating refined iron and chromium from polymetallic hazardous waste (for the process flow of phosphate-containing sludge, see figure 1 )

[0084] (1) Raw material analysis

[0085] Take the comprehensive sludge containing phosphate and add Fe to the sludge 3+ Salt mix well to make Fe:Cr - =2.5~3.5:1, the metal content was analyzed with a flame atomic absorption spectrophotometer, and the phosphate content was analyzed with a visible spectrophotometer. The results are shown in Table 5.

[0086] Table 5 Metal composition list of phosphate-containing comprehensive sludge

[0087] .

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 separating and refining iron and chromium from polymetallic hazardous waste. The phosphate radicals carried by sludge are utilized to precipitate Fe<3+> selectively for preparing iron phosphate and isolating Fe<3+> from Cr<3+>, and since Cr<3+> can be precipitated by the phosphate radicals, a method of excessive Fe<3+> is adopted to prevent the formation of chromium phosphate precipitation in the process; the residual Fe<3+> can be reduced to Fe<2+> by scrap iron, then an alkaline solution is added to adjust the pH to a certain value so as to selectively precipitate Cr<3+> for preparing chromium hydroxide, and further separation of iron and chromium can be achieved. According to the method for separating and refining iron and chromium from the polymetallic hazardous waste, no heating is needed during the whole process, ferric ions and the phosphate radicals in the hazardous waste are comprehensively utilized, and thus the cost is low; meanwhile, no waste water and waste residues are produced, and thus the method is environment-friendly; iron phosphate and chromium hydroxide can be obtained from respective extraction, wherein iron phosphate has high economic values and can be used in battery materials, ceramics and other raw materials, and chromium hydroxide can be used in pigments, chemicals and other industry raw materials.

Description

technical field [0001] The invention belongs to the technical field of hydrometallurgy, and in particular relates to a method for separating refined iron and chromium from polymetallic hazardous waste. Background technique [0002] At present, my country's polymetallic hazardous waste is mainly sludge or wastewater produced by electroplating, surface treatment, smelting, chemical industry and other industries, which contains a variety of metals, including iron, chromium, copper, zinc, nickel, cobalt, manganese, etc. . Chromium is a highly toxic heavy metal that easily enters human cells, causing damage to liver, kidney and other internal organs and DNA, and accumulates in the human body. It is carcinogenic and may induce the risk of gene mutation. The discharge of chromium-containing sludge or wastewater into the environment not only easily causes environmental water pollution, but also poses a direct threat to human life and health. Therefore, it is very important to reali...

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
IPC IPC(8): C01B25/37C01G37/00C01G49/02C01F11/46
CPCC01B25/375C01F11/46C01G37/00C01G49/02
Inventor 王修海贾智慧
Owner 青川县天运金属开发有限公司
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