Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for separating Cr and Fe from pickling waste liquor

A separation method and a technology for pickling waste liquid, which are applied in the direction of chemical instruments and methods, chromium compounds, process efficiency improvement, etc., can solve problems such as difficult separation, poor separation effect of iron ions and chromium ions, and achieve cost saving Effect

Active Publication Date: 2019-03-29
CHANGZHOU WUJIN YOUBANG WATER PURIFICATION MATERIALS
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to overcome the defects and deficiencies that the separation effect of iron ions and chromium ions in the existing pickling waste liquid is not good, and it is difficult to completely separate them, and provide a method for separating chromium and iron in the pickling waste liquid. Two-step separation extraction and stripping of valence iron and chromium ions, using the selective extraction of different extractants to achieve a complete separation of chromium and iron

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] The raw material of this embodiment is 400 kilograms of stainless steel pickling wastewater, and its acidity (acidity of sulfuric acid) is measured to be 5.3%, the content of chromium ion is 4.5 g / L, the content of ferric iron is 2.8 g / L, and the content of ferrous iron is 75 g / L .

[0036] A method for separating chromium and iron in pickling waste liquid, comprising the steps of:

[0037] S1. Extraction of ferric iron: Add ferric organic extractant to the pickling waste liquid, carry out continuous centrifugal extraction at room temperature to separate ferric ions, and obtain ferric organic phase and aqueous phase of ferrous ions and chromium ions, of which three Valence iron extractant contains 20% trioctyl tertiary amine, 20% dodecyl dimethyl tertiary amine, 10% tributyl phosphate, 50% sulfonated kerosene, and the amount added is 0.5 times the mass of pickling waste liquid ;

[0038] S2. Back extraction of ferric iron: use sulfuric acid solution to back extract fe...

Embodiment 2

[0046] The raw material of this embodiment is 500 kg of stainless steel pickling waste water, and its acidity (acidity of sulfuric acid) is 4.1%, the content of chromium ion is 2.1 g / L, the content of ferric iron is 7.8 g / L, and the content of ferrous iron is 71 g / L .

[0047] A method for separating chromium and iron in pickling waste liquid, comprising the steps of:

[0048] S1. Extraction of ferric iron: Add ferric organic extractant to the pickling waste liquid, carry out continuous centrifugal extraction at room temperature to separate ferric ions, and obtain ferric organic phase and aqueous phase of ferrous ions and chromium ions, of which three Valence iron extractant contains 15% dodecyl tertiary amine, 20% N,N-dimethylhexadecyl tertiary amine, 5% tributyl phosphate, 60% sulfonated kerosene, the amount added is pickling waste liquid 1.6 times the mass;

[0049] S2. Back extraction of ferric iron: use sulfuric acid solution to back extract ferric iron in the organic p...

Embodiment 3

[0057] The raw material of this embodiment is 1000 kg of stainless steel pickling waste water, and its acidity (acidity of sulfuric acid) is 3.8%, the content of chromium ion is 4.8g / L, the content of ferric iron is 7.0 g / L, and the content of ferrous iron is 65 g / L .

[0058] A method for separating chromium and iron in pickling waste liquid, comprising the steps of:

[0059] S1. Extraction of ferric iron: Add ferric organic extractant to the pickling waste liquid, carry out continuous centrifugal extraction at room temperature to separate ferric ions, and obtain ferric organic phase and aqueous phase of ferrous ions and chromium ions, of which three The valent iron extractant contains 30% trioctyl tertiary amine, 10% dodecyl tertiary amine, 10% tributyl phosphate, and 50% sulfonated kerosene, and the amount added is 1.4 times the quality of the pickling waste liquid;

[0060] S2. Back extraction of ferric iron: use sulfuric acid solution to back extract ferric iron in the o...

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 Cr and Fe from pickling waste liquor. The method for separating Cr and Fe from the pickling waste liquor comprises the following steps of three-valent iron ion extraction, three-valent iron ion reextraction, chromium ion extraction and chromium ion reextraction. According to the method for separating Cr and Fe from the pickling waste liquor, the three-valent iron ions are separated and obtained through organic extraction and sulfuric acid reextraction, the phenomenon of incomplete reduction of the three-valent iron ions in a reduction method canbe avoided, the influence of the three-valent iron ions on the chromium ions extraction separation can be avoided, the chromium ion solution and the three-valent iron ion solution are obtained throughseparation by a specific extraction-reextraction system, high-price chromium salt products can be prepared through the concentration and crystallization treatment, and the ferrous ion containing acidsolution after chromium separation can be used for preparing iron-based water purifying agents. According to the method for separating Cr and Fe from the pickling waste liquor, after the recovery ofextraction agents, the content of the ferric ions is 25 ppm or below, and the content of chromium ions is 28 ppm or below, so that the pickling liquor can be recycled, the cost of the extraction agentis saved and the cyclic economy is realized.

Description

technical field [0001] The invention relates to the technical field of waste water recovery, in particular to a method for separating chromium and iron in pickling waste liquid. Background technique [0002] Pickling is an essential process in the production of stainless steel, which not only ensures the good quality of the steel surface, but also prepares it for further processing. With the process of pickling, metal oxides are continuously dissolved and enter the pickling solution. The hydrogen ions in the original pickling solution are gradually replaced by metal salts, the concentration of acid gradually decreases, and the concentration of metal salts increases accordingly, so the speed of dissolving oxides in the pickling solution gradually slows down, and it is necessary to continuously discharge waste liquid and replenish new pickling solution. This used waste liquid with poor pickling effect is the pickling waste liquid. The components of these waste liquids are c...

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): C22B3/40C22B7/00C22B34/32C01G37/00
CPCC01G37/00C22B7/006C22B34/32C22B3/402C22B3/409Y02P10/20
Inventor 朱松锋蒋银峰居银栋蒋浩李萍
Owner CHANGZHOU WUJIN YOUBANG WATER PURIFICATION MATERIALS