Method for preparing chromium oxide green by using ferrochrome

A chrome oxide green and ferrochrome technology, which is applied to cells, electrolysis processes, electrolysis components, etc., can solve problems such as environmental pollution and land occupation, and achieve the effect of simplifying process equipment.

Active Publication Date: 2017-12-29
QINGHAI INST OF SALT LAKES OF CHINESE ACAD OF SCI +1
View PDF9 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Another equally urgent problem is that a considerable part of the tens of thousands of tons of chromium oxide green produced each year is produced by calcining chromic anhydride, and the toxic solid waste generated by the workshop producing chromic anhydride is piled up, not only occupying land , and caused serious pollution to the environment
[0012] Various methods for preparing chromate in the industry can reduce or reduce the emission of Cr (Ⅵ) in chromium slag to a certain extent, but cannot completely avoid the existence of hexavalent chromium in slag.

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 preparing chromium oxide green by using ferrochrome
  • Method for preparing chromium oxide green by using ferrochrome
  • Method for preparing chromium oxide green by using ferrochrome

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0092] Embodiment 1: The high-concentration sodium chromate solution prepared by electrolysis with ferrochrome and sodium hydroxide electrolyte, separated and precipitated is the preparation raw material of chromium oxide green, and the high-concentration sodium chromate solution contains microparticle carbon, and the content of microparticle carbon About 1.0g / L~5g / L.

[0093] Take 500mL of sodium chromate with a concentration of 530g / L and a high-concentration sodium chromate electrolyte with a carbon content of about 5g / L as the raw material, react at 280°C and 8.2MPa for 6h, then terminate the hydrothermal reaction, and lower the temperature to room temperature A solid-liquid mixture slurry is obtained. It is subjected to solid-liquid separation, and the liquid phase obtains a pure chromate solution, and the solid phase obtains a solid phase of chromium hydroxide. The obtained chromium hydroxide solid phase was calcined at 1000°C for 2 hours in an air atmosphere, and then ...

Embodiment 2

[0094] Example 2: The preparation of chromium oxide green by the hydrothermal method is illustrated by taking ferrochromium and sodium hydroxide electrolyte electrolytically prepared high-concentration sodium chromate solution containing microparticle carbon as raw material and adding citric acid as reducing agent.

[0095](1) Take 61mL of sodium chromate electrolyte with a sodium chromate concentration of 263g / L as a raw material, add 8.4g of citric acid, and react at 200°C for 3 hours to terminate the hydrothermal reaction. When the temperature drops to room temperature, the solid-liquid Mix slurry. It is subjected to solid-liquid separation, and the liquid phase obtains a pure chromate solution, and the solid phase obtains a solid phase of chromium hydroxide. The obtained chromium hydroxide solid phase was calcined at 1000°C for 2 hours in an air atmosphere, and then the calcining reaction was terminated. After the temperature dropped to room temperature, the obtained solid...

Embodiment 3

[0097] Example 3: The preparation of chromium oxide green by hydrothermal method is illustrated by taking ferrochromium and sodium hydroxide electrolyte electrolytically prepared high-concentration sodium chromate solution containing microparticle carbon as raw material and adding carbon powder as reducing agent.

[0098] (1) Take 300mL of sodium chromate electrolyte with a concentration of 390g / L of sodium chromate as raw material, add 3.25g of carbon powder, react at 280°C for 3 hours, then terminate the hydrothermal reaction, and obtain a solid-liquid mixture when the temperature drops to room temperature Slurry. It is subjected to solid-liquid separation, and the liquid phase obtains a pure chromate solution, and the solid phase obtains a solid phase of chromium hydroxide. The obtained chromium hydroxide solid phase was calcined at 1000°C for 2 hours in an air atmosphere, and then the calcining reaction was terminated. After the temperature dropped to room temperature, the...

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 relates to a method for preparing chromium oxide green by using ferrochrome. The method comprises the following steps: electrolysis devices which comprises an electrolytic cell, a double-cathode device, a double-anode device, an insulation partition plate, a plurality of sedimentation tanks and electrodes are provided; an electrolyte solution undergoes an electrolytic reaction in a self-circulation mode, the temperature of the electrolyte solution in the electrolytic cell is automatically controlled to be 20-60 DEG C, the circulating reacting time for the electrolyte solution is controlled according to a formula 1 being t=c1*V1*M2 *Eta / (2*n*M1*I), and solid-liquid separating treatment is carried out to obtain a high-concentration chromate solution; the high-concentration chromate solution is guided into a reaction kettle for carrying out hydrothermal reaction, under the pressure of 2-10 MPa, the chromate solution in the reaction kettle is heated to 180-280 DEG C and reacted for 2-12 hours to obtain a hydrothermal reaction slurry, and filtering separating treatment is carried out to obtain a chromium hydroxide solid; and calcinating treatment is carried out on the chromium hydroxide solid to obtain the chromium oxide green.

Description

technical field [0001] The invention relates to the development and utilization technology of chromite, in particular to a method for preparing chromium oxide green by using ferrochrome. Background technique [0002] Chromium salt products play a very important and irreplaceable role in the national economy and people's lives, and the chromium salt industry is one of the most competitive resource raw material industries in the world. As the parent product of chromium salt, chromate is an indispensable and important chemical raw material in the development of national economy. Chromium salt products based on chromate include: dichromate, chromic anhydride, chromium oxide, chrome yellow and chromium salt essence (basic chromium sulfate), etc. These products are widely used in metallurgy, pigments, tanning, dyes, spices, metal surface treatment, welding electrodes, coinage, catalysts, printing and dyeing, medicine and other industries. According to statistics, 10% of the commo...

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): C25B1/00C25B9/06C25B9/18C25B15/08C25B15/02C25B9/17
CPCC25B1/00C25B15/02C25B15/08C25B9/17C25B9/70
Inventor 董亚萍冯海涛李武梁建李波张波郑竹林史建斌王永全杨维德史海琴
Owner QINGHAI INST OF SALT LAKES OF CHINESE ACAD OF SCI
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