CN104561614A

CN104561614A - Process for recycling rare earth from south ion adsorption type rare earth ore leaching mother liquor

Info

Publication number: CN104561614A
Application number: CN201510044259.0A
Authority: CN
Inventors: 孙东江; 王志勇; 林海; 林春雷; 王强; 李钊; 程哲
Original assignee: Ganzhou Rare Earth Mining Industry Co Ltd
Current assignee: Ganzhou Rare Earth Mining Industry Co Ltd
Priority date: 2015-01-29
Filing date: 2015-01-29
Publication date: 2015-04-29

Abstract

The invention relates to a process for recycling rare earth from south ion adsorption type rare earth ore leaching mother liquor. The process comprises the following steps: collecting mine rare earth leaching mother liquor, preparing P204 organic phase, extracting rare earth, precipitating rare earth double salt to decontaminate, carrying out alkali converting on sulfuric acid rare earth double salt and the like. According to the process for recycling rare earth from the south ion adsorption type rare earth ore leaching mother liquor, rare earth ions are gathered by P204, sulfuric acid is used for reverse extraction, sodium sulfate is added to reverse extraction liquor to carry out double salt precipitation, sodium hydroxide is used for alkali converting to obtain rare earth hydroxide, a large amount of ammonium bicarbonate used for precipitation is reduced, the rare earth ions are separated from foreign ions through double salt precipitation and alkali converting, the product quality is improved, and the cost of late separation pretreatment is reduced. The process has the advantages that occupied area is small, treatment device is centralized, rare earth recovery is high and larger than or equal to 95%, large mine can be intensive, strong support is provided for finally reaching standard of ammonia nitrogen discharge of mine wastewater, rare earth mine mother liquor does not need pretreatment, ammonia nitrogen is not increased, and the production cost is low.

Description

Recovering rare earth technique in south ion adsorption type rare earth ore leaching mother liquor

Technical field

The present invention relates to rare-earth mineral recovery process, recovering rare earth technique in especially a kind of southern ion adsorption type rare earth ore leaching mother liquor.

Background technology

Ion adsorption type rare earth ore is also known as weathered superficial leaching rare-earth ore, and late 1960s finds in Longnan, Jiangxi Province, thereafter in succession in Fujian, Hunan, Guangdong, the Nanling mountains such as Guangxi be all found.Through the research of decades, find out that the type ore deposit distribute ground is wide, reserves are large, and radioactivity is low, and easily, Extraction of rare earth technique is simple, good product quality in exploitation.Ion adsorption type rare earth ore system forms clay mineral containing REE-granite or volcanics through weathering for many years, the rare earth ion dissociateed with hydrated ion or hydroxyl hydration ionic adsorption on clay mineral.The rare earth ion be adsorbed on clay mineral does not dissolve and is not hydrolyzed yet in water, but follows ion-exchange rule, useful chemical method Extraction of rare earth.Mine is many in hilly country, is loose husky clay, color adularescent, grey, redness, yellow.Density is 2.0-2.5g/cm ³, Products of mine is mixed rare earth oxide, and its ree distribution pattern alters a great deal, and has light rare earths type, heavy rare earths type and middle heavy rare earths type.Rare earth element 80% ~ 90% in ore is adsorbed on the clay mineral such as kaolin and hydromica in ionic condition; Be adsorbed on the water insoluble or ethanol of rare-earth cation on clay mineral, but at strong electrolyte (as NaCl, (NH ₄) ₂sO ₄, NH ₄cl etc.) can ion-exchange be there is in solution and enter solution and there is reversible reaction.

Its exploitation tool singularity of south ion type rareearth ore, go through the development of three more than ten years, the process of mine-for-leach mother liquor, from oxalic acid precipitation carbon ammonium pre-treatment precipitation by now, never breaks away from this problem of environment, the rate of recovery waste that also result in part rare earth resources on the low side simultaneously.

Summary of the invention

Object of the present invention is just to provide one can recovering rare earth well, can reduce again ammonia nitrogen to recovering rare earth technique in the southern ion adsorption type rare earth ore leaching mother liquor of the pollution of environment.

Recovering rare earth technique in southern ion adsorption type rare earth ore leaching mother liquor of the present invention, comprises the following steps:

1, mine rare earth leaching mother liquor is collected, and the rare earth leaching mother liquor containing more than 0.1g/l is incorporated into collecting tank, is stored to mother liquor pond to be extracted after Plate Filtration;

2, P ₂0 ₄organic phase is prepared, by P ₂0 ₄with kerosene 1:2.5-3.5 stirring and evenly mixing by volume, put into extraction tank;

3, rare earth extraction, mother liquor to be extracted for mother liquor pond is piped to single-stage circulation extracting system, and mother liquor directly extracts, and organic phase circulates, and aqueous phase is discharged, and the remaining liquid rare earth concentration of test, after organic phase middle-weight rare earths concentration reaches 0.15mol/L, adds the H of 7mol/L ₂sO ₄back extraction is carried out as strippant;

4, double salt of rare earth removing impurity by means of precipitation, proceeds to the Na that reactor adds 2.5 times of content of rare earth by the strip liquor of step 3 ₂sO ₄carry out double salt of rare earth precipitation;

5, sulfuric acid rare earth double salt alkali transforms, sulfuric acid rare earth double salt is insoluble in acid, so rare earth hydrate must be converted into through alkali, add content of rare earth to mix with sulfuric acid rare earth double salt slurry with the sodium hydroxide of the theoretical amount 1.5 times of alkali reaction, make system temperature maintain 75-85 DEG C of reaction 1-2 hour, rear washing is to SO ₄ ^2- _,n _a ⁺rare earth smelting factory separation of rare earth elements is sent in press filtration after ﹤ 1%, filter cake.

Recovering rare earth technique in southern ion adsorption type rare earth ore leaching mother liquor of the present invention, uses P ₂0 ₄enrichment rare earth ion, sulfuric acid back extraction, strip liquor sodium sulfate obtains double salt precipitation, carry out alkali with sodium hydroxide to turn and obtain rare earth hydrate, a large amount of bicarbonate of ammonia of precipitation are decreased in technological process, and double salt precipitation and alkali turn and make rare earth ion obtain with foreign ion to be separated, improve quality product, decrease the cost of later stage separation and culture, there is floor space little, treatment facility is concentrated, rare earth yield is high>=and 95%, can accomplish intensive to large-scale mine, to the discharge of final mine wastewater, ammonia nitrogen is up to standard provides strong support, Rare-earth Mine mother liquor is without the need to pre-treatment, increase without ammonia nitrogen, the feature that production cost is low.

Embodiment

Embodiment: with 1000m ³concentration is the rare earth mother solution of 0.2g/l is example.

Processing step:

1, collect rare earth and leach mother liquor, in_situ leaching mine being contained more than 0.1g/l flows out mother liquor introduces collecting tank, crosses after plate-and-frame filter press and is stored in mother liquor pond, test mother liquor rare earth concentration and impurity concentration and pH value;

2, the preparation of organic phase: will p ₂ 0 ₄ withkerosene stirs 30min mixing by 1:3 volume ratio loading retort, imports in extraction tank, extraction tank size: mixing section 1500L, clarifying chamber 24000L;

3, rare earth extraction: the mother liquor of step 1 is imported mixing section by pipeline, be communicated with organic phase circulating line simultaneously and carry out cycling extraction, organic phase adopts self-circulation, and raffinate discharges, the remaining liquid rare earth concentration of test, stops extraction as extraction liquid rare earth concentration >=0.05g/l;

4, rare earth is stripped: with H ₂sO ₄as strippant, the load organic phases after above-mentioned extraction is imported in reextraction retort, add 7mol/l H ₂sO ₄back extraction, organic phase: aqueous phase=2:1;

5, double salt precipitation: imported to by the strip liquor of step 4 in double salt precipitation bucket, surveys rare earth concentration, adds NaSO with 2.5 of total amount of rare earth times ₄precipitating rare earth double salt, filters, and filtrate returns for next reextraction dosing;

6, alkali transforms double salt of rare earth is rare earth hydrate: alkali turning barrel put into by double salt step 5 produced, add clear water, liquid-solid ratio 1:2, the NaOH solid adding the theoretical amount 1.5 times of content of rare earth and alkali reaction stirs 2 hours, then add clear water to waft to liquid-solid ratio 10:1 and wash 2 times, Plate Filtration, product send rare earth smelting factory to be separated

RE ₂(SO ₄) ₃. NaSO ₄+ 6NaOH=2RE (OH) ₃+ 8Na ₂sO ₄; Washing of precipitate water is for returning leaching ore deposit dosing pond dosing.

Claims

1. a recovering rare earth technique in southern ion adsorption type rare earth ore leaching mother liquor, is characterized in that: it comprises the following steps:

(1), mine rare earth leaching mother liquor collect, by containing more than 0.1g/l rare earth leach mother liquor be incorporated into collecting tank, be stored to mother liquor pond after Plate Filtration to be extracted;

(2), P ₂0 ₄organic phase is prepared, by P ₂0 ₄with kerosene 1:2.5-3.5 stirring and evenly mixing by volume, put into extraction tank;

(3), rare earth extraction, mother liquor to be extracted for mother liquor pond is piped to single-stage circulation extracting system, and mother liquor directly extracts, organic phase circulates, and aqueous phase is discharged, the remaining liquid rare earth concentration of test, after organic phase middle-weight rare earths concentration reaches 0.15mol/L, add the H of 7mol/L ₂sO ₄back extraction is carried out as strippant;

(4), double salt of rare earth removing impurity by means of precipitation, the strip liquor of step (3) is proceeded to the Na that reactor adds 2.5 times of content of rare earth ₂sO ₄carry out double salt of rare earth precipitation;

(5), sulfuric acid rare earth double salt alkali transform, add content of rare earth and mix with sulfuric acid rare earth double salt slurry with the sodium hydroxide of the theoretical amount 1.5 times of alkali reaction, make system temperature maintain 75-85 DEG C react 1-2 hour, rear washing is to SO ₄ ^2- _,n _a ⁺rare earth smelting factory separation of rare earth elements is sent in press filtration after ﹤ 1%, filter cake.