阅读说明：本技术 一种结晶尾液萃取回收钪与浓缩工艺 (Scandium extraction and recovery and concentration process for crystallization tail liquid ) 是由 穆宇 高利坤 张裕书 张少翔 张新良 蒋朋 陈超 刘能云 于 2020-07-09 设计创作，主要内容包括：本发明公开了一种结晶尾液萃取回收钪与浓缩工艺,包括如下步骤：(1)将结晶尾液经三级逆流萃取得到负载有机相和萃余液；(2)将负载有机相经反萃、过滤得到粗钪渣和滤液；(3)将萃余液进行浓缩、过滤得到硫酸铁。本发明通过三级逆流萃取、一级反萃有效地将结晶尾液中的钪元素进行回收,同时将萃余液进行浓缩过滤后得到硫酸铁和浓缩废酸液。硫酸铁可作为产品直接出售,浓缩废酸液中硫酸浓度约为50％(体积浓度),可作为浸出剂使用。(The invention discloses a process for extracting, recovering and concentrating scandium from crystallization tail liquid, which comprises the following steps: (1) carrying out three-stage countercurrent extraction on the crystallization tail liquid to obtain a loaded organic phase and raffinate; (2) carrying out back extraction and filtration on the loaded organic phase to obtain coarse scandium slag and filtrate; (3) concentrating and filtering raffinate to obtain ferric sulfate. The method effectively recovers scandium element in the tail liquid of crystallization through three-stage countercurrent extraction and one-stage back extraction, and simultaneously obtains ferric sulfate and concentrated acid pickle after concentrating and filtering raffinate. Ferric sulfate can be directly sold as a product, and the concentration of sulfuric acid in the concentrated waste acid liquor is about 50% (volume concentration), so that the ferric sulfate can be used as a leaching agent.)

1. A scandium extraction and recovery and concentration process by using crystallization tail liquid is characterized by comprising the following steps:

s1: carrying out three-stage countercurrent extraction on the crystallization tail liquid to obtain a loaded organic phase and raffinate;

s2: carrying out back extraction and filtration on the loaded organic phase to obtain coarse scandium slag and filtrate;

s3: concentrating and filtering raffinate to obtain ferric sulfate.

2. The scandium extraction, recovery and concentration process of the crystallization tail liquid according to claim 1, wherein the step S1 specifically comprises: and sequentially carrying out primary extraction, secondary extraction, tertiary extraction, secondary extraction and primary extraction on the crystallization tail liquid to obtain raffinate and a loaded organic phase.

3. The scandium extraction, recovery and concentration process of the tail liquid of the crystallization of claim 1, wherein the step S2 includes the following sub-steps:

s21: carrying out back extraction on the loaded organic phase to obtain a coarse scandium precipitate and an organic phase;

s22: filtering the coarse scandium precipitate to obtain coarse scandium slag and filtrate;

s23: sodium hydroxide is supplemented in the filtrate, and then the filtrate is added into a first-stage back extraction process for recycling.

4. The scandium extraction, recovery and concentration process of the crystallization tail liquid as claimed in claim 3, wherein the step S2 further includes the following sub-steps:

s24: adding sulfuric acid into the organic phase to carry out organic phase regeneration to obtain a regenerated organic phase and regenerated waste liquid (namely backwater);

s25: adding the regenerated organic phase into an extraction process to obtain a loaded organic phase for recycling;

s26: and concentrating and crystallizing the regenerated waste liquid to obtain a sodium sulfate byproduct.

5. The scandium extraction, recovery and concentration process of the tail liquid of the crystallization of claim 4, wherein the step S2 further includes the following sub-steps:

s27: and regenerating the sodium sulfate byproduct to obtain sodium hydroxide, wherein the sodium hydroxide is used as a back extractant.

6. The scandium extraction, recovery and concentration process of the tail liquid of the crystallization of claim 1, wherein the step S3 includes the following sub-steps:

s31: heating and concentrating raffinate to obtain ferric sulfate precipitate;

s32: and filtering the ferric sulfate precipitate to obtain ferric sulfate and concentrated waste acid liquor.

7. The process for extracting and recovering scandium and concentrating according to claim 6, wherein the heating temperature in the step S31 is 110-150 ℃.

Technical Field

The invention belongs to the technical field of scandium recovery, and particularly relates to a process for extracting and recovering scandium and concentrating crystallization tail liquid.

Background

After the crude product of the aluminum ammonium sulfate is subjected to vacuum crystallization and filtration, the generated crystallization tail liquid contains scandium with a large concentration, so that the scandium has a recovery value. However, the prior art does not have a process for recycling scandium, so that the requirement of recycling each element in the raw ore cannot be met.

Disclosure of Invention

The invention provides a process for extracting and recovering scandium and concentrating crystallization tail liquid, which aims to overcome the defects of the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

a scandium extraction and recovery and concentration process by using crystallization tail liquid comprises the following steps:

s1: carrying out three-stage countercurrent extraction on the crystallization tail liquid to obtain a loaded organic phase and raffinate;

s2: carrying out back extraction and filtration on the loaded organic phase to obtain coarse scandium slag and filtrate;

s3: concentrating and filtering raffinate to obtain ferric sulfate.

As a further description of the above technical solution: the step S1 specifically includes: and sequentially carrying out primary extraction, secondary extraction, tertiary extraction, secondary extraction and primary extraction on the crystallization tail liquid to obtain raffinate and a loaded organic phase.

As a further description of the above technical solution: the step S2 includes the following sub-steps:

s21: carrying out back extraction on the loaded organic phase to obtain a coarse scandium precipitate and an organic phase;

s22: filtering the coarse scandium precipitate to obtain coarse scandium slag and filtrate;

s23: sodium hydroxide is supplemented in the filtrate, and then the filtrate is added into a first-stage back extraction process for recycling.

As a further description of the above technical solution: the step S2 further includes the following sub-steps:

s24: adding sulfuric acid into the organic phase to carry out organic phase regeneration to obtain a regenerated organic phase and regenerated waste liquid (namely backwater);

s25: adding the regenerated organic phase into an extraction process to obtain a loaded organic phase for recycling;

s26: and concentrating and crystallizing the regenerated waste liquid to obtain a sodium sulfate byproduct.

As a further description of the above technical solution: the step S2 further includes the following sub-steps:

s27: and regenerating the sodium sulfate byproduct to obtain sodium hydroxide, wherein the sodium hydroxide is used as a back extractant.

As a further description of the above technical solution: the step S3 includes the following sub-steps:

s31: heating and concentrating raffinate to obtain ferric sulfate precipitate;

s32: and filtering the ferric sulfate precipitate to obtain ferric sulfate and concentrated waste acid liquor.

As a further description of the above technical solution: the heating temperature in the step S31 is 110-150 ℃.

The invention has the following beneficial effects:

the method effectively recovers scandium element in the tail liquid of crystallization through three-stage countercurrent extraction and one-stage back extraction, and simultaneously obtains ferric sulfate and concentrated acid pickle after concentrating and filtering raffinate. Ferric sulfate can be directly sold as a product, and the concentration of sulfuric acid in the concentrated waste acid liquor is about 50% (volume concentration), so that the ferric sulfate can be used as a leaching agent.

Drawings

FIG. 1 is a flow chart of the process for recovering scandium and concentrating by extraction of crystallization tail liquid.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

A scandium extraction and recovery and concentration process by using crystallization tail liquid comprises the following steps:

(1) carrying out three-stage countercurrent extraction on the crystallization tail liquid to obtain a loaded organic phase and raffinate;

(2) carrying out back extraction and filtration on the loaded organic phase to obtain coarse scandium slag and filtrate;

(3) concentrating and filtering raffinate to obtain ferric sulfate.

In an embodiment, the step (1) is specifically: and sequentially carrying out primary extraction, secondary extraction, tertiary extraction, secondary extraction and primary extraction on the crystallization tail liquid to obtain raffinate and a loaded organic phase.

In an embodiment, said step (2) comprises the sub-steps of:

(21) carrying out back extraction on the loaded organic phase to obtain a coarse scandium precipitate and an organic phase;

(22) filtering the coarse scandium precipitate to obtain coarse scandium slag and filtrate;

(23) supplementing sodium hydroxide into the filtrate, and adding the filtrate into a primary back extraction process for recycling;

(24) adding sulfuric acid into the organic phase to carry out organic phase regeneration to obtain a regenerated organic phase and regenerated waste liquid (namely backwater);

(25) adding the regenerated organic phase into an extraction process to obtain a loaded organic phase for recycling;

(26) concentrating and crystallizing the regenerated waste liquid to obtain a sodium sulfate byproduct;

(27) and regenerating the sodium sulfate byproduct to obtain sodium hydroxide, wherein the sodium hydroxide is used as a back extractant.

In an embodiment, said step (3) comprises the sub-steps of:

(31) heating and concentrating raffinate to obtain ferric sulfate precipitate;

(32) and filtering the ferric sulfate precipitate to obtain ferric sulfate and concentrated waste acid liquor.

In an embodiment, the heating temperature in step (31) is 110-.

The method effectively recovers scandium element in the tail liquid of crystallization through three-stage countercurrent extraction and one-stage back extraction, and simultaneously obtains ferric sulfate and concentrated acid pickle after concentrating and filtering raffinate. Ferric sulfate can be directly sold as a product, and the concentration of sulfuric acid in the concentrated waste acid liquor is about 50% (volume concentration), so that the ferric sulfate can be used as a leaching agent.