Method for removing hexavalent chromium in the process of preparing nickel-cobalt hydroxide from laterite nickel ore

A technology of nickel cobalt hydroxide and laterite nickel ore, which is applied in the field of metallurgy and can solve problems such as unqualified products

Active Publication Date: 2022-07-26
CHINA ENFI ENGINEERING CORPORATION
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The main purpose of the present invention is to provide a method for removing hexavalent chromium in the process of preparing nickel-cobalt hydroxide from laterite nickel ore, so as to solve the problem of nickel-cobalt hydroxide produced by the high-pressure acid leaching process in the prior art due to the hexavalent chromium content. Too high and the product is unqualified

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 removing hexavalent chromium in the process of preparing nickel-cobalt hydroxide from laterite nickel ore
  • Method for removing hexavalent chromium in the process of preparing nickel-cobalt hydroxide from laterite nickel ore

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0054] Taking a laterite nickel ore in Indonesia as the implementation object, the chromium content in the laterite nickel ore is 1.37%. The laterite nickel ore is made into a slurry with a concentration of 28 wt %, and a first reducing agent is added to the laterite nickel ore slurry, specifically a compound agent with a ratio of sulfur to pyrite of 1:1, which is in total with the laterite nickel ore. The chromium mass ratio is 1:1. Preheat to 200°C, then heat up, and carry out high-pressure acid leaching at a reaction temperature of 250°C, an acid-to-ore ratio of 200Kg / t, and a reaction time of 1h. The leaching rates were 95.25% and 91.04%, respectively.

Embodiment 2

[0056] The difference with Example 1 is only: the chromium content in the laterite nickel ore is 2.14%, the first reducing agent is to use sulfur alone, and the total chromium mass ratio between the first reducing agent and the laterite nickel ore is 1:3, and the content of Ni and Co is 1:3. The leaching rates were 95.81% and 91.45% respectively; the concentration of hexavalent chromium after high pressure leaching was less than 0.5mg / L.

Embodiment 3

[0058] The only difference from Example 1 is that the chromium content in the laterite nickel ore is 2.42%, the ratio of sulfur to pyrite is 4:1, the reaction temperature is 250°C, and the leaching rates of Ni and Co are 97.14% and 96.45%, respectively; The concentration of hexavalent chromium after high pressure leaching is less than 0.5mg / L.

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 provides a method for removing hexavalent chromium in the process of preparing nickel-cobalt hydroxide from laterite nickel ore. In the method: before the high pressure acid leaching step, the laterite nickel ore slurry is preheated, and before the preheating step, a first reducing agent is added to the laterite nickel ore slurry, and then the laterite nickel ore added with the first reducing agent is made to The pulp enters the high-pressure acid leaching step; the first reducing agent is one or more of pyrite, sulfur and chromite, or is organic waste water; or, the second reducing agent is added to the leachate obtained in the circulating leaching step, Then enter the residual ore neutralization step; the second reducing agent is one of alkali metal or alkaline earth metal sulfite, pyrosulfite, ferrous salt, thiosulfate, sulfide salt, hydrogen sulfite or several. Using the method provided by this method, hexavalent chromium can be removed from the source on the basis of not changing the high pressure leaching process of laterite nickel ore, so as to prevent it from producing nickel cobalt hydroxide products, and it will not affect the original steps.

Description

technical field [0001] The invention relates to the technical field of metallurgy, in particular to a method for removing hexavalent chromium in the process of preparing nickel-cobalt hydroxide from laterite nickel ore. Background technique [0002] The preparation of nickel-cobalt hydroxide from laterite nickel ore usually adopts high-pressure acid leaching process, which mainly includes high-pressure acid leaching, circulating leaching, residual ore neutralization, pre-neutralization, CCD countercurrent washing, one-stage iron and aluminum removal, two-stage iron and aluminum removal, and one-stage It is composed of nickel-cobalt immersion and two-stage nickel-cobalt immersion. Some laterite nickel ores will produce hexavalent chromium in the high-pressure acid leaching process, and finally produce nickel-cobalt hydroxide products containing hexavalent chromium, and the presence of hexavalent chromium will affect the performance of nickel-cobalt hydroxide products. Compar...

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 Patents(China)
IPC IPC(8): C01G53/00C01G53/04C22B3/00C22B3/06C22B3/44
CPCC01G53/00C01G53/04C22B3/06C22B3/44C22B23/0415C22B23/0461
Inventor 李勇孙宁磊丁剑刘苏宁林洁媛曹敏彭建华
Owner CHINA ENFI ENGINEERING CORPORATION
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