阅读说明：本技术 一种从海洋稀土硫酸浸出液中分离制备稀土钇富集物的方法 (Method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution ) 是由 张魁芳 刘志强 王瑞祥 钟晓聪 陶进长 袁祥奕 于 2021-06-18 设计创作，主要内容包括：本发明公开了一种从海洋稀土硫酸浸出液中分离制备稀土钇富集物的方法。该方法,包括如下步骤：(1)将第一有机相与海洋稀土硫酸浸出液进行错流萃取,得到一次负载有机相和一次萃余液,所述的第一有机相由N235、TBP和磺化煤油组成；(2)将第二有机相与步骤(1)得到的一次萃余液进行逆流萃取,得到二次负载有机相和二次萃余液,所述的第二有机相由Cyanex 272和磺化煤油组成；(3)取步骤(2)得到的二次负载有机相加入草酸溶液,搅拌,待完全分相后,取下层水相过滤得到稀土钇富集物。本发明实现了从海洋稀土硫酸浸出液中高效分离富集稀土钇,该方法简单易于实现,回收的稀土钇富集物非稀土杂质含量小于1％。(The invention discloses a method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution. The method comprises the following steps: (1) carrying out cross-flow extraction on the first organic phase and a marine rare earth sulfuric acid leaching solution to obtain a primary loaded organic phase and a primary raffinate, wherein the first organic phase consists of N235, TBP and sulfonated kerosene; (2) carrying out countercurrent extraction on a second organic phase and the primary raffinate obtained in the step (1) to obtain a secondary loaded organic phase and a secondary raffinate, wherein the second organic phase consists of Cyanex 272 and sulfonated kerosene; (3) and (3) adding the secondary loaded organic phase obtained in the step (2) into oxalic acid solution, stirring, and after complete phase separation, taking the lower aqueous phase and filtering to obtain the rare earth yttrium concentrate. The method realizes the high-efficiency separation and enrichment of rare earth yttrium from the marine rare earth sulfuric acid leaching solution, is simple and easy to realize, and the content of non-rare earth impurities in the recovered rare earth yttrium concentrate is less than 1 percent.)

1. A method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution is characterized by comprising the following steps:

(1) carrying out 1-5-stage cross-flow extraction on the first organic phase and the marine rare earth sulfuric acid leaching solution according to the extraction ratio O/A of 1-4: 1 for 5-15 min to obtain a primary loaded organic phase and a primary raffinate, wherein the first organic phase consists of N235, TBP and sulfonated kerosene;

(2) carrying out 1-5-stage countercurrent extraction on a second organic phase and the primary raffinate obtained in the step (1) according to the extraction ratio O/A of 1: 1-5 for 5-15 min to obtain a secondary loaded organic phase and a secondary raffinate, wherein the second organic phase consists of Cyanex 272 and sulfonated kerosene;

(3) and (3) adding an oxalic acid solution into the secondary loaded organic phase obtained in the step (2) according to the ratio of O/A to O/A of 1-10: 1, stirring for 10-30 min, and after complete phase separation, taking the lower layer of water phase and filtering to obtain the rare earth yttrium concentrate.

2. The method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution according to claim 1, wherein the first organic phase comprises 10-40% of N235, 5-20% of TBP and 40-85% of sulfonated kerosene by volume fraction.

3. The method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution according to claim 1, wherein the second organic phase consists of 10-40% Cyanex 272 and 60-90% sulfonated kerosene by volume fraction.

4. The method for preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution according to claim 1, wherein the oxalic acid solution has a molar concentration of 0.5-1 mol/L.

5. The method of claim 1, wherein the rare earth yttrium concentrate is separated from the marine rare earth sulfuric acid leach liquor, and the marine rare earth sulfuric acid leach liquor contains rare earth Y³⁺0.1～1.5g/L，Fe³⁺5～10g/L、Al³⁺1～5g/L、Mn²⁺1～5g/L、Mg²⁺1～5g/L、Ca²⁺0.1-0.5 g/L, and a pH value of 0-0.5.

Technical Field

The invention relates to the technical field of hydrometallurgy, in particular to a method for separating and preparing rare earth yttrium concentrate from a marine rare earth sulfuric acid leaching solution.

Background

The rare earth elements have abundant and unique magnetic, optical, electric and other properties, are indispensable or alternative strategic materials for developing high and new technologies and national defense advanced technologies and modifying traditional industries in all countries in the world at present, and are non-renewable precious resources.

China is the largest land rare earth resource reserve country in the world, the role of world rare earth supply is almost born in the last decades, new rare earth resources are found in international countries, and marine rare earth resources are found and proposed. The appearance of marine rare earth resources brings new changes and opportunities to the world rare earth pattern, so that the development and utilization of marine rare earth resources are highly regarded by the international society, particularly developed countries such as the United states and the Japanese.

The research shows that: the ocean rare earth is rich in rare earth yttrium and mainly exists in the form of rare earth phosphate. Because the solubility product of the rare earth phosphate is small, the rare earth phosphate can only be dissolved in a strong acid system. At present, sulfuric acid leachate is obtained mainly through high-concentration sulfuric acid leaching, and then rare earth is separated and enriched from the leachate. Because the ocean rare earth has complex components and low rare earth yttrium grade, the obtained sulfuric acid leaching solution has high acidity, a plurality of impurity ion types and high concentration (especially Fe)³⁺)、Y³⁺The concentration is low, the technical difficulty of separating and enriching rare earth yttrium is greatly increased, and the recycling of yttrium in ocean rare earth is restricted.

Disclosure of Invention

The invention aims to provide a method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching liquid, which realizes high-efficiency separation and enrichment of rare earth yttrium from the marine rare earth sulfuric acid leaching liquid, and is simple and easy to realize, and the content of non-rare earth impurities in the recovered rare earth yttrium concentrate is less than 1%.

In order to achieve the purpose, the invention adopts the technical scheme that: a method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution comprises the following steps:

(1) carrying out 1-5-stage cross flow extraction on the first organic phase and the marine rare earth sulfuric acid leaching solution according to the extraction ratio O/A of 1-4: 1 for 5-15 min to obtain a primary loaded organic phase and a primary raffinate, wherein the first organic phase consists of N235, TBP and sulfonated kerosene;

(2) carrying out 1-5-stage countercurrent extraction on a second organic phase and the primary raffinate obtained in the step (1) according to the extraction ratio O/A of 1: 1-5 for 5-15 min to obtain a secondary loaded organic phase and a secondary raffinate, wherein the second organic phase consists of Cyanex 272 and sulfonated kerosene;

(3) and (3) adding an oxalic acid solution into the secondary loaded organic phase obtained in the step (2) according to the ratio of O/A to O/A of 1-10: 1, stirring for 10-30 min, and after complete phase separation, taking the lower layer of water phase and filtering to obtain the rare earth yttrium concentrate.

Preferably, the first organic phase consists of 10-40% of N235(N, N-dioctyl-1-octylamine), 5-20% of TBP (tributyl phosphate) and 40-85% of sulfonated kerosene by volume fraction.

Preferably, the second organic phase consists of, in volume fraction, 10% to 40% Cyanex 272 (bis (2,4, 4-trimethylpentyl) phosphinic acid) and 60% to 90% sulfonated kerosene.

Preferably, the molar concentration of the oxalic acid solution is 0.5-1 mol/L.

Preferably, the marine rare earth sulfuric acid leaching solution contains rare earth Y³⁺0.1～1.5g/L，Fe³⁺5～10g/L、Al³⁺1～5 g/L、Mn²⁺1～5g/L、Mg²⁺1～5g/L、Ca²⁺0.1-0.5 g/L, and a pH value of 0-0.5.

Compared with the prior art, the invention has the beneficial effects that:

the invention provides a method for separating and preparing rare earth yttrium concentrate from a marine rare earth sulfuric acid leaching solution. According to the method, the high-efficiency separation of rare earth yttrium, iron and other impurities in the marine rare earth sulfuric acid leaching solution is realized by utilizing the difference of extraction and back extraction properties of a mixed organic phase consisting of N235, TBP and sulfonated kerosene and the mixed organic phase consisting of Cyanex 272 and sulfonated kerosene relative to rare earth yttrium, iron and other impurity ions in a step-by-step extraction and selective precipitation manner, and the rare earth yttrium concentrate is prepared. The method is simple and easy to realize, and the content of the non-rare earth impurities in the recovered rare earth yttrium concentrate is less than 1 percent.

Detailed Description

The following examples are further illustrative of the present invention and are not intended to be limiting thereof. The equipment and reagents used in the present invention are, unless otherwise specified, conventional commercial products in the art.

A method for separating and preparing rare earth yttrium concentrate from marine rare earth sulfuric acid leaching solution comprises the following steps:

(1) carrying out 1-5-stage cross flow extraction on the first organic phase and the marine rare earth sulfuric acid leaching solution according to the extraction ratio O/A of 1-4: 1 for 5-15 min to obtain a primary loaded organic phase and a primary raffinate, wherein the first organic phase consists of N235, TBP and sulfonated kerosene;

(2) carrying out 1-5-stage countercurrent extraction on a second organic phase and the primary raffinate obtained in the step (1) according to the extraction ratio O/A of 1: 1-5 for 5-15 min to obtain a secondary loaded organic phase and a secondary raffinate, wherein the second organic phase consists of Cyanex 272 and sulfonated kerosene;

(3) and (3) adding an oxalic acid solution into the secondary loaded organic phase obtained in the step (2) according to the ratio of O/A to O/A of 1-10: 1, stirring for 10-30 min, and after complete phase separation, taking the lower layer of water phase and filtering to obtain the rare earth yttrium concentrate.

The rare earth Y is contained in the marine rare earth sulfuric acid leaching solution³⁺0.1～1.5g/L，Fe³⁺5～10g/L、Al³⁺1～5g/L、 Mn²⁺1～5g/L、Mg²⁺1～5g/L、Ca²⁺0.1-0.5 g/L, and a pH value of 0-0.5.

In the following examples, the first organic phase consists of the following volume fractions of the starting materials: 10 to 40 percent of N235(N, N-dioctyl-1-octylamine), 5 to 20 percent of TBP (tributyl phosphate) and 40 to 85 percent of sulfonated kerosene. Further preferably, the first organic phase consists of the following volume fractions of the starting materials: 20 to 40 percent of N235(N, N-dioctyl-1-octylamine), 10 to 20 percent of TBP (tributyl phosphate) and 50 to 70 percent of sulfonated kerosene.

In the following examples, the second organic phase consists of the following volume fractions of the starting materials: 10 to 40 percent of Cyanex 272 (di (2,4, 4-trimethylpentyl) phosphinic acid) and 60 to 90 percent of sulfonated kerosene.

In the following examples, the molar concentration of the oxalic acid solution is 0.5 to 1.0 mol/L.

Example 1

A method for separating and preparing rare earth yttrium concentrate from a marine rare earth sulfuric acid leaching solution, wherein the marine rare earth sulfuric acid leaching solution contains the following components: rare earth Y³⁺1.478g/L、Fe³⁺9.77g/L、Al³⁺4.89g/L、Mn²⁺4.24g/L、Mg²⁺4.98g/L、Ca^{2 +}0.39g/L, pH ═ 0.18, comprising the steps of:

(1) carrying out 1-stage cross-flow extraction on the first organic phase and the marine rare earth sulfuric acid leaching solution according to the extraction phase ratio O/A of 4:1, wherein the extraction time is 10min, the Fe extraction rate is 89.38%, rare earth yttrium and other impurity ions are not extracted basically, so as to obtain a primary loaded organic phase (iron-containing organic phase) and a primary raffinate, and the first organic phase consists of 30% of N235, 10% of TBP and 60% of sulfonated kerosene in terms of volume fraction;

(2) carrying out 5-stage countercurrent extraction on the second organic phase and the primary raffinate obtained in the step (1) according to the extraction ratio of O/A (oxygen to oxygen) of 1:1, wherein the extraction time is 10min, the extraction rate of Fe is 100%, the extraction rate of rare earth yttrium is 99.31%, other impurity ions are not extracted basically, and a secondary loaded organic phase (iron and yttrium-containing organic phase) and a secondary raffinate are obtained, wherein the second organic phase consists of 30% of Cyanex 272 and 70% of sulfonated kerosene in terms of volume fraction;

(3) and (3) adding 0.5 mol/L oxalic acid solution into the secondary loaded organic phase (the iron and yttrium-containing organic phase) obtained in the step (2) according to the ratio of 1:1 of O/A, stirring for 10min, and after complete phase separation, taking the lower layer of water phase and filtering to obtain the rare earth yttrium concentrate.

The non-rare earth impurities in the rare earth yttrium enrichment are less than 1 percent.

Example 2

A method for separating and preparing rare earth yttrium concentrate from a marine rare earth sulfuric acid leaching solution, wherein the marine rare earth sulfuric acid leaching solution contains the following components: rare earth Y³⁺0.16g/L、Fe³⁺5.19g/L、Al³⁺1.17g/L、Mn²⁺1.05g/L、Mg²⁺1.59g/L、Ca²⁺0.11 g/L, pH, comprising the steps of:

(1) and (3) carrying out 4-stage cross-flow extraction on the first organic phase and the marine rare earth sulfuric acid leaching solution according to the extraction ratio O/A of 2:1, wherein the extraction time is 5min, the Fe extraction rate is 97.93%, and rare earth yttrium and other impurity ions are not extracted basically to obtain a primary loaded organic phase (iron-containing organic phase) and a primary raffinate. The first organic phase consisted of 20% N235, 10% TBP and 70% sulfonated kerosene by volume fraction;

(2) and (2) carrying out 5-stage countercurrent extraction on the second organic phase and the primary raffinate obtained in the step (1) according to the extraction ratio of O/A (oxygen to oxygen) of 1:5, wherein the extraction time is 5min, the Fe extraction rate is 100%, the Y extraction rate is 99.56%, and other impurity ions are not extracted basically, so that a secondary loaded organic phase (iron-yttrium-containing organic phase) and a secondary raffinate are obtained. The second organic phase consisted of 40% Cyanex 272 and 60% sulfonated kerosene on a volume fraction basis;

(3) and (3) adding 1.0mol/L oxalic acid solution into the secondary loaded organic phase (the iron and yttrium-containing organic phase) obtained in the step (2) according to the ratio of O/A of 10:1, stirring for 30min, and after complete phase separation, taking the lower layer of water phase and filtering to obtain the rare earth yttrium concentrate.

The non-rare earth impurities in the rare earth yttrium enrichment are less than 1 percent.

Example 3

A method for separating and preparing rare earth yttrium concentrate from a marine rare earth sulfuric acid leaching solution, wherein the marine rare earth sulfuric acid leaching solution contains the following components: rare earth Y³⁺0.16g/L、Fe³⁺5.19g/L、Al³⁺1.17g/L、Mn²⁺1.05g/L、Mg²⁺1.59g/L、Ca²⁺0.The method comprises the following steps of (1) setting 11 g/L, pH to 0:

(1) carrying out 4-stage cross-flow extraction on the first organic phase and the marine rare earth sulfuric acid leaching solution according to the extraction phase ratio O/A of 1:1, wherein the extraction time is 15min, the Fe extraction rate is 96.17%, rare earth yttrium and other impurity ions are not extracted basically, so as to obtain a primary loaded organic phase (iron-containing organic phase) and a primary raffinate, and the first organic phase consists of 40% of N235, 10% of TBP and 50% of sulfonated kerosene in terms of volume fraction;

(2) and (2) carrying out 1-stage countercurrent extraction on the second organic phase and the primary raffinate obtained in the step (1) according to the extraction ratio of O/A (oxygen to oxygen) of 1:1, wherein the extraction time is 15min, the Fe extraction rate is 98.12%, the Y extraction rate is 88.73%, and other impurity ions are not extracted basically, so that a secondary loaded organic phase (iron and yttrium-containing organic phase) and a secondary raffinate are obtained. The second organic phase consisted of 10% Cyanex 272 and 90% sulfonated kerosene on a volume fraction basis;

(3) and (3) adding 0.5 mol/L oxalic acid solution into the secondary loaded organic phase (the iron and yttrium-containing organic phase) obtained in the step (2) according to the ratio of 1:1 of O/A, stirring for 10min, and after complete phase separation, taking the lower layer of water phase and filtering to obtain the rare earth yttrium concentrate.

The non-rare earth impurities in the rare earth yttrium enrichment are less than 1 percent.

Example 4

A method for separating and preparing rare earth yttrium concentrate from a marine rare earth sulfuric acid leaching solution, wherein the marine rare earth sulfuric acid leaching solution contains the following components: rare earth Y³⁺1.478g/L、Fe³⁺9.77g/L、Al³⁺4.89g/L、Mn²⁺4.24g/L、Mg²⁺4.98g/L、Ca^{2 +}0.39g/L, pH ═ 0.5, comprising the steps of:

(1) and (3) carrying out 3-stage cross-flow extraction on the first organic phase and the marine rare earth sulfuric acid leaching solution according to the extraction ratio of O/A (oxygen to oxygen) of 1:1, wherein the extraction time is 10min, the Fe extraction rate is 95.41%, and rare earth yttrium and other impurity ions are not extracted basically, so that a primary loaded organic phase (iron-containing organic phase) and a primary raffinate are obtained. The first organic phase consisted of 30% N235, 20% TBP and 50% sulfonated kerosene, in volume fractions;

(2) and (2) carrying out 5-stage countercurrent extraction on the second organic phase and the primary raffinate obtained in the step (1) according to the extraction ratio of O/A (oxygen to oxygen) of 1:1, wherein the extraction time is 10min, the Fe extraction rate is 100%, the Y extraction rate is 98.73%, and other impurity ions are not extracted basically, so that a secondary loaded organic phase (iron-yttrium-containing organic phase) and a secondary raffinate are obtained. The second organic phase consisted of 40% Cyanex 272 and 60% sulfonated kerosene on a volume fraction basis;

(3) and (3) adding 1.0mol/L oxalic acid solution into the secondary loaded organic phase (the iron and yttrium-containing organic phase) obtained in the step (2) according to the ratio of 1:1 of O/A, stirring for 30min, and after complete phase separation, taking the lower layer of water phase and filtering to obtain the rare earth yttrium concentrate.

The non-rare earth impurities in the rare earth yttrium enrichment are less than 1 percent.

The above is only a preferred embodiment of the present invention, and it should be noted that the above preferred embodiment should not be considered as limiting the present invention, and the protection scope of the present invention should be subject to the scope defined by the claims. It will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the spirit and scope of the invention, and these modifications and adaptations should be considered within the scope of the invention.