Process for reducing rare earth loss during value adjustment of phosphorus-containing rare earth feed liquid by using iron phosphorus removal and segmented value adjustment method

Abstract

The invention discloses a process for reducing rare earth loss in value adjustment of phosphorus-containing rare earth feed liquid by using an iron phosphorus removal and segmented value adjustment method, and belongs to the field of rare earth hydrometallurgy. The process comprises the following steps: preparing iron, heating, adding carbon for material settling, controlling REO concentration, performing primary value adjustment, performing solid-liquid separation, performing secondary value adjustment and performing solid-liquid separation again. The method comprises the following steps: adding an iron material of which the stoichiometric ratio is 1-2 times that of a phosphorus-containing rare earth feed liquid into the phosphorus-containing rare earth feed liquid, raising the temperature to 50 DEG C or above, adding a carbon precipitation material to regulate the acidity to 0.1-0.6 mol / L, controlling REO to be less than or equal to 200g / L, regulating the pH to 0.5-2, carrying out primary phosphorus removal, separating to obtain iron phosphate slag with low rare earth content, and regulating the pH of clear liquid to 4-5 to further remove impurities; according to the method, the rare earth content in the value-adjusted slag is remarkably reduced, the dry basis CeO content of the primary value-adjusted slag can be as low as 1.61%, the rare earth yield is increased, the occupied area of a slag warehouse is reduced, recycling of phosphorus resources is achieved, and the production cost is reduced.

Description

TECHNICAL FIELD

[0002] The application belongs to the technical field of rare earth hydrometallurgy, and relates to a process for reducing rare earth loss in value adjustment of a phosphorus-containing rare earth solution by iron dephosphorization and segmented value adjustment. BACKGROUND

[0003] Rare earth has excellent optical, electrical, magnetic and other properties, and is widely used in national defense and high-tech new material fields, and is known as "industrial vitamin". A key process in rare earth hydrometallurgy is rare earth solution impurity removal, one of the widely used methods of which is value adjustment. At present, single rare earth separation mainly adopts an extraction separation method using P507 (2-ethylhexyl phosphonic acid mono (2-ethylhexyl) ester) as an extractant, but the system has problems such as large acid and alkali consumption and ammonia nitrogen pollution.

[0004] One of the main problems in value adjustment of a phosphorus-containing rare earth solution is large rare earth loss, and a large amount of value adjustment slag with high REO content (dry basis REO content is as high as 40-60%, and dry basis cerium oxide content is 20-30%) is produced, which needs to be extracted again to increase cost and occupy warehouse land. In recent years, researchers have proposed various rare earth separation and impurity removal methods, such as using functional ionic liquid as an extractant, solid-supported ionic liquid extraction, and aqueous two-phase system separation, but these methods have low impurity removal rate for divalent metals such as iron and aluminum, or the process is complex and the cost is high, which is difficult to apply to industrial production.

[0005] For the treatment of iron-containing rare earth solution, the prior art discloses a method of roasting iron removal and simultaneous pH value control flotation, which removes iron minerals through pre-oxidation roasting, reduction roasting and other steps, but the method belongs to mineral processing technology and is not suitable for the impurity removal process of the phosphorus-containing rare earth solution in hydrometallurgy. Therefore, it is of great significance to develop a process that can effectively reduce the rare earth loss in the value adjustment process of the phosphorus-containing rare earth solution and recover the valuable element phosphorus. SUMMARY

[0006] The purpose of the present application is to provide a process for reducing rare earth loss in value adjustment of a phosphorus-containing rare earth solution by iron dephosphorization and segmented value adjustment, to solve the problem of large rare earth loss in the value adjustment process of the phosphorus-containing rare earth solution, to improve the rare earth yield of the system, to reduce production cost, and to recover the valuable element phosphorus.

[0007] The technical scheme adopted by the present application is as follows: A process for reducing rare earth loss in value adjustment of a phosphorus-containing rare earth solution by iron dephosphorization and segmented value adjustment, the process for reducing rare earth loss in value adjustment of a phosphorus-containing rare earth solution by iron dephosphorization and segmented value adjustment comprises the following steps: (1) Iron preparation: according to the phosphorus content in the rare earth solution, iron-containing materials (hydroxide, chloride, etc. can provide iron ions, and the materials can use by-products such as hydroxide and chloride produced in rare earth hydrometallurgy to reduce costs) are added to the solution, heated and stirred to fully dissolve.

[0008] (2) Temperature rise: the solution is heated to above 50℃.

[0009] (3) Carbon precipitation: add rare earth carbonate (which can be prepared by low REO content solution or waste water), stir to fully dissolve, and reduce the solution acidity to 0.1-0.6mol / L.

[0010] (4) Control of total REO content: control the REO content in the rare earth solution to be ≤200g / L.

[0011] (5) First value adjustment: add value adjustment materials (such as ammonium bicarbonate, sodium carbonate, ammonia, sodium hydroxide, etc. Alkaline materials or carbonates, or their solutions), reduce the solution pH to 0.5-2. Continue to stir and fully react. Before adding the value adjustment material, first separate the undissolved slag containing iron and carbon precipitate, and use the clear liquid to adjust the value, which is more effective.

[0012] (6) Solid-liquid separation: use solid-liquid separation equipment such as plate and frame filter, centrifuge or suction filter tank to obtain the first value adjustment solution and the first value adjustment slag. The first value adjustment slag has low rare earth content and high iron phosphate content, and the valuable elements such as iron and phosphorus can be further recovered.

[0013] (7) Second value adjustment: heat the first value adjustment liquid to above 50℃, add value adjustment materials (such as ammonium bicarbonate, sodium carbonate, ammonia, sodium hydroxide, etc. Alkaline materials or carbonates, or their solutions), adjust the pH to 4-5, and further remove non-rare earth impurities in the solution.

[0014] (8) Solid-liquid separation: use solid-liquid separation equipment such as plate and frame filter, centrifuge or suction filter tank to obtain the second value adjustment neutralization solution and the second value adjustment slag. The second value adjustment neutralization solution is used as qualified solution for subsequent process. The second value adjustment slag can continue to extract rare earth.

[0015] The working principle of the present application is: through the specific reaction of iron ions and phosphate ions and the segmented pH adjustment, the selective removal of phosphorus impurities and the minimization of rare earth loss are realized.

[0016] Under acidic conditions, iron ions (Fe³⁺) and phosphate ions (PO4³⁻) in the solution will react to form insoluble iron phosphate precipitate (FePO4), and the reaction equation is: Fe³⁺+PO4³⁻→FePO4↓. By controlling the amount of iron ions to be 1-2 times the stoichiometric ratio of phosphorus content, the phosphate ions can be fully precipitated and removed.

[0017] The segmental adjusting value strategy is based on the solubility difference of rare earth ions and impurity ions under different pH conditions: in the low pH range of pH=0.5-2, the iron phosphate precipitate has high stability, and the phosphorus impurity can be efficiently separated and removed, while the rare earth ions still mainly exist in the form of soluble ions in the solution, thereby reducing the loss of rare earth; in the higher pH range of pH=4-5, the remaining non-rare earth impurities (such as aluminum, iron, etc.) will form hydroxide precipitate to realize further impurity removal, and the rare earth ions still have good solubility.

[0018] Raising the temperature to above 50 DEG C can promote the reaction rate of iron ions and phosphate ions, and improve the precipitation efficiency; controlling the acidity of the material liquid to 0.1-0.6 mol / L and REO≤200 g / L can avoid the co-precipitation of rare earth ions; using rare earth carbonate as carbon precipitation material can not only adjust the acidity, but also improve the total recovery rate of rare earth.

[0019] The iron phosphate slag is separated from the rare earth material liquid through solid-liquid separation to realize the recycling of phosphorus; the secondary adjusting value further purifies the rare earth material liquid to ensure the product quality of the subsequent process. Through resource recycling and precise control, the whole process realizes the minimization of rare earth loss and the maximization of resource utilization.

[0020] In summary, due to the adoption of the above technical solutions, the present application has the following advantages: 1. A process for reducing the adjusting value rare earth loss of a phosphorus-containing rare earth material liquid by using iron to remove phosphorus and a segmental adjusting value method, which greatly reduces the rare earth content in the adjusting value slag, and the dry basis CeO2 content in the primary adjusting value slag can be as low as 1.61%, which is much lower than the 20-30% in the prior art, thereby improving the system yield and reducing the cost.

[0021] 2. The present application reduces the amount of high-REO adjusting value slag and the land occupation of the slag storage.

[0022] 3. The present application recovers the impurity phosphorus in the material liquid and improves the resource recycling rate of the rare earth production process.

[0023] 4. The present application uses the by-product of rare earth hydrometallurgy as raw material to reduce the production cost and realize the resource utilization of waste.

[0024] 5. The process of the present application is simple, easy to operate and easy to be applied in industry. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings, wherein: Figure 1is a process flow diagram of the present application. DETAILED DESCRIPTION

[0026] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application, i.e., the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application generally described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without making creative efforts fall within the scope of the present application.

[0028] It should be noted that the relational terms such as "first" and "second" and the like are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus including a series of elements includes not only those elements, but also other elements not explicitly listed or inherent to such a process, method, article or apparatus. Without more limitations, the element defined by the phrase "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus including the element.

[0029] The features and performances of the present application will be further described in detail below with reference to the embodiments.

[0030] Embodiment One The present application is a process for reducing the loss of rare earth elements in the value adjustment of rare earth solution containing phosphorus by using iron to remove phosphorus and segmented value adjustment method, comprising the following steps: (1) 12 m3 of chlorinated rare earth solution (REO = 142.68 g / L) is transferred into a reaction tank, and the temperature is raised to 80°C; (2) The amount of iron-containing material is calculated according to the content of phosphate in the solution. During the heating process, 244.4 kg of by-product iron hydroxide (the iron amount is 1.5 times the stoichiometric ratio of the phosphorus content) is added and stirred to dissolve completely; (3) Carbon sink material (recovered rare earth carbonate) is added to the solution to a acidity of 0.15 mol / L. During the heating process, it is stirred to dissolve completely; (4) Control the REO in the feed solution to be 142.68 g / L; (5) Separate the incompletely dissolved slag first, slowly add the by-product ammonia water to the clear solution until the pH is 1.5-2, and fully react; (6) Add a flocculating agent to clarify, transfer the clear solution to a secondary value adjustment tank, and pass the slag slurry through a plate and frame filter to obtain a primary value adjustment slag; (7) Raise the temperature of the secondary value adjustment tank to 80℃, slowly add the by-product ammonia water until the pH is 4, and fully react; (8) Flocculate and clarify, transfer the clear solution to the next process, and pass the slag slurry through a plate and frame filter to obtain a secondary value adjustment slag.

[0031] Results: The dry basis CeO2 content of the primary value adjustment slag is 7.05%, and the dry basis CeO2 content of the secondary value adjustment slag is 13.27%. Compared with the traditional process, the loss of rare earth is reduced by more than 60%. The iron phosphate content in the primary value adjustment slag reaches more than 65%, which can be used for recycling iron and phosphorus.

[0032] Example Two The process for reducing the loss of rare earth in the value adjustment of a phosphorus-containing rare earth feed solution by using iron to remove phosphorus and a segmented value adjustment method, comprising the following steps: (1) Transfer 12.23 m³ of chlorinated rare earth feed solution (REO = 142.85 g / L) to a reaction tank, and raise the temperature to 85℃; (2) Calculate the amount of iron-containing material according to the phosphate content in the feed solution, and add 264 kg of by-product iron hydroxide (the iron amount is 1.7 times the stoichiometric ratio of the phosphorus content) during the temperature raising process, and fully dissolve under stirring; (3) Add carbon sinking material (for recycling rare earth carbonate) to the feed solution until the acidity is 0.1 mol / L, fully dissolve under stirring during the temperature raising process, flocculate and clarify, and transfer the clear solution to a primary value adjustment tank; (4) Control the REO in the feed solution to be 142.85 g / L; (5) Slowly add sodium carbonate solution to the clear solution until the pH is 1.5-2, and fully react; (6) Add a flocculating agent to clarify, transfer the clear solution to a secondary value adjustment tank, and pass the slag slurry through a centrifuge to obtain a primary value adjustment slag; (7) Raise the temperature of the secondary value adjustment tank to 85℃, slowly add sodium carbonate solution until the pH is 4.5, and fully react; (8) Flocculate and clarify, transfer the clear solution to the next process, and pass the slag slurry through a centrifuge to obtain a secondary value adjustment slag.

[0033] Results: The dry basis CeO2 content of the primary value adjustment slag is 3.53%, and the dry basis CeO2 content of the secondary value adjustment slag is 13.64%. The iron phosphate content in the primary value adjustment slag reaches 70%, and the phosphorus recovery rate is increased to more than 85%.

[0034] Example Three This invention discloses a process for reducing rare earth loss in phosphorus-containing rare earth solutions by using iron dephosphorization and segmented adjustment methods, comprising the following steps: (1) Transfer rare earth chloride solution with REO=122g / L into the reaction vessel, dilute with water to REO=74g / L, the volume of the diluted solution is 14m³, and heat to 90℃; (2) Calculate the amount of iron-containing material based on the phosphate content in the liquid. During the heating process, add by-product ferric chloride (the amount of iron is 1.2 times the stoichiometric ratio of the phosphorus content) and stir until fully dissolved. (3) Add carbon precipitate (recover rare earth carbonate) to the liquid until the acidity is 0.3 mol / L, and stir to dissolve completely during the heating process; (4) Control the REO concentration in the feed solution to 74 g / L; (5) First separate the undissolved residue, then slowly add sodium hydroxide wastewater to the clear liquid until the pH=1.5, allowing it to react fully; (6) Add flocculant to clarify, transfer the clear liquid to the secondary conditioning tank, and separate the slurry through the suction filter tank to obtain the primary conditioning residue; (7) Heat the secondary pH adjustment tank to 90°C, slowly add sodium hydroxide wastewater until pH=5, and allow it to react completely; (8) Flocculation and clarification, the clear liquid is transferred to the next process, and the slurry is separated by a filter tank to obtain secondary slurry.

[0035] Results: The CeO2 content of the primary conditioning residue (dry basis) was only 1.61%, the REO content of the primary conditioning solution was 72.4 g / L, and the rare earth loss rate was less than 3%. The CeO2 content of the secondary conditioning residue (dry basis) was 12.83%, which can be returned to the system for further rare earth extraction. In this embodiment, all system byproducts were used as conditioning materials, reducing raw material costs by more than 40%.

[0036] Example 4 This invention discloses a process for reducing rare earth loss in phosphorus-containing rare earth solutions by using iron dephosphorization and segmented adjustment methods, comprising the following steps: (1) Transfer 10 m³ of rare earth chloride solution with REO=135 g / L into the reaction vessel, dilute with water to REO=98 g / L (the volume after dilution is 13.8 m³), ​​start stirring and heat to 82℃; (2) The phosphorus content in the solution was found to be 0.72 g / L. Based on the stoichiometric ratio of 1.4 times the phosphorus content, 186 kg of by-product ferric chloride (purity ≥90%) was added and stirred for 30 min until completely dissolved. (3) Slowly add the carbon precipitate (dry basis REO=8%) prepared by the low REO content precipitate to the precipitate, and check the acidity while adding, until the acidity of the precipitate drops to 0.5 mol / L, and stir for 15 min to ensure that the carbon precipitate is completely dissolved; (4) The sample detection of the material liquid REO is 97.8 g / L, which meets the control requirement of ≤100 g / L; (5) The fine slag particles (about 0.3 kg / m³) not completely dissolved are separated by using a suction filter tank, and the ammonium bicarbonate solution (concentration of 20%) is slowly added into the clear liquid to control the pH slowly rising to 1.8, and the stirring is continued for 40 min for full reaction; (6) The polyacrylamide flocculating agent with a concentration of 0.1% is added, and after standing for 20 min, the clear liquid is transferred into a secondary setting tank, and the slag slurry is filtered by a plate-frame filter to obtain a primary setting slag; (7) The secondary setting tank is heated to 82°C, the ammonium bicarbonate solution is continuously added, the pH is adjusted to 4.8, and the stirring is continued for 35 min; (8) The flocculating agent is added again and the clear liquid is detected, the REO is 95.2 g / L, the phosphorus content is ≤0.03 g / L, and the qualified material liquid is sent to the extraction process; and the slag slurry is filtered to obtain a secondary setting slag.

[0037] Results: The dry basis CeO2 content of the primary setting slag is 4.12%, the iron phosphate content is 68.5% (the iron and phosphorus can be recycled), the dry basis CeO2 content of the secondary setting slag is 14.02% (which can be returned to the ore dissolving process for rare earth extraction), the total loss rate of rare earth is only 4.5%, which is reduced by 70% compared with the traditional process, and the single batch processing cost is reduced by 38 yuan / m³ due to the use of by-product ferric chloride and ammonium bicarbonate.

[0038] Experimental Example One Experimental Purpose The differences between the "iron phosphorus removal + staged setting value" process of the application and the traditional "single step setting value impurity removal" process in terms of rare earth loss rate, phosphorus removal rate, slag amount and cost are compared to verify the technical advantages of the application.

[0039] Experimental Materials The phosphorus-containing chlorinated rare earth material liquid of a certain rare earth plant is used uniformly: REO = 130 ± 2 g / L, phosphorus content 0.8 ± 0.05 g / L, acidity 1.2 mol / L, and the volume is 5 m³ / group.

[0040] Experimental Design Experimental Steps Each group processes the material liquid according to the above parameters, and records the key operation data (such as reagent consumption, reaction time); Detection indexes: dry basis CeO2 content of the primary setting slag, dry basis CeO2 content of the secondary setting slag, residual phosphorus content of the material liquid, total loss rate of rare earth (calculated according to the difference between the total amount of REO in and out of the material liquid), total yield of setting slag (dry slag amount / material liquid volume), and unit processing cost (reagents + energy consumption + equipment depreciation).

[0041] Experimental Results Experimental analysis Rare earth loss comparison: The control group has no iron removal step, and the phosphorus and rare earth co-precipitation leads to a CeO2 content of 25.36% in the first adjusting slag, and the total loss rate is 18.2%; while the experimental group generates iron phosphate precipitate by preferential combination of iron ions with phosphorus (CeO2 in the first adjusting slag ≤4.57%), combined with pH control in stages (low pH for phosphorus removal and high pH for impurity removal), the total loss rate of rare earth is reduced to 3.8%-5.1%, which is more than 70% less than the traditional process, reflecting the synergistic effect of "iron removal + staged adjustment", and solving the core pain point of high rare earth loss in the traditional process.

[0042] Phosphorus removal and resource recovery: The phosphorus removal rate of the control group is only 30% (residual 0.56g / L), and the phosphorus is discarded with high rare earth slag, which cannot be recovered; the phosphorus removal rate of the experimental group is ≥96% (residual ≤0.03g / L), the iron phosphate content in the first adjusting slag is ≥65%, and the iron (recovery rate ≥85%) and phosphorus (preparation of ammonium phosphate, recovery rate ≥80%) can be recovered by acid dissolution-iron precipitation process, realizing the resource utilization of impurities, in line with the green metallurgical concept, which is a technical effect that cannot be achieved by the traditional process.

[0043] Cost and environmental protection: The experimental group uses rare earth wet metallurgy by-products (by-product iron hydroxide / chloride, low REO carbon sediment material), and the slag amount is reduced by 50% (slag bank area is reduced by 50%), the unit processing cost is reduced by 35%-37% compared with the control group, and the energy consumption and pollution of secondary treatment of high rare earth slag are reduced, which has economic and environmental benefits.

[0044] In summary, the process of the present application realizes multiple technical breakthroughs of rare earth loss reduction, phosphorus resource recovery, and cost reduction through the innovative design of "iron removal and phosphorus removal priority + precise pH control in stages", and has significant creativity and practicality compared with the traditional process.

[0045] The above only describes the preferred embodiments of the present application and does not limit the protection scope of the present application, and any modifications, equivalent replacements and improvements made by any person skilled in the art within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A process for reducing the loss of rare earths in the adjustment of rare earths in a rare earth solution containing phosphorus by using a method of iron dephosphorization and segmented adjustment, characterized in that, The method comprises the following steps: (1) iron preparation: according to the phosphorus content in the rare earth solution, iron-containing material with 1-2 stoichiometric ratio is added to the solution, heated and stirred to fully dissolve; (2) temperature rising: the solution is heated to above 50℃; (3) carbon precipitation: rare earth carbonate is added, stirred to fully dissolve, and the solution acidity is reduced to 0.1-0.6 mol / L; (4) total REO control: the REO content in the rare earth solution is controlled to be less than or equal to 200 g / L; (5) primary value adjustment: value adjustment material is added to reduce the solution pH to 0.5-2, and the solution is continuously stirred to fully react; (6) solid-liquid separation: solid-liquid separation equipment is used to obtain the primary value adjustment solution and the primary value adjustment residue; (7) secondary value adjustment: the primary value adjustment solution is heated to above 50℃, value adjustment material is added, and the pH is adjusted to 4-5 to further remove non-rare earth impurities in the solution; (8) solid-liquid separation: solid-liquid separation equipment is used to obtain the secondary value adjustment neutralization solution and the secondary value adjustment residue, and the secondary value adjustment neutralization solution is used as qualified solution for subsequent processes.

2. The process of reducing the loss of rare earths in the adjustment of rare earths in a rare earth solution containing phosphorus by a method of phosphorus removal by iron and segmented adjustment according to claim 1, characterized by, The iron-containing material in step (1) is iron hydroxide or iron chloride, and the iron hydroxide or iron chloride is by-produced in rare earth hydrometallurgy.

3. The process of reducing the loss of rare earths by adjusting the value of rare earths in the phosphorus-containing rare earth solution by the method of iron dephosphorization and segmented value adjustment according to claim 1, characterized in that, The amount of iron preparation in step (1) is 1.2-1.7 times the phosphorus content.

4. The process of reducing the loss of rare earths by adjusting the value of rare earths in a rare earth solution containing phosphorus by using the iron dephosphorization and segmented value adjustment method according to claim 1, characterized in that, In step (2), the solution is heated to above 80℃.

5. The process of reducing the loss of rare earths by adjusting the value of rare earths in the phosphorus-containing rare earth solution by the method of iron dephosphorization and segmented value adjustment according to claim 1, characterized in that, The rare earth carbonate in step (3) is carbon precipitation material prepared from low REO content solution or waste water, and the solution acidity is reduced to 0.3-0.5 mol / L.

6. The process of reducing the loss of rare earths by adjusting the value of rare earths in a rare earth solution containing phosphorus by using the iron dephosphorization and segmented value adjustment method according to claim 1, characterized in that, In step (4), the REO content in the rare earth solution is controlled to be less than or equal to 100 g / L.

7. The process of reducing the loss of rare earths by adjusting the value of rare earths in a rare earth solution containing phosphorus by using the iron dephosphorization and segmented value adjustment method according to claim 1, characterized in that, In step (5), before adding the value adjustment material, the residue of the iron-containing material and the carbon precipitation material that is not fully dissolved is separated, and the clear solution is used for value adjustment, and the primary value adjustment endpoint pH is 1.5-2.

8. The process of reducing the loss of rare earths by adjusting the value of rare earths in a rare earth solution containing phosphorus by using the iron dephosphorization and segmented value adjustment method according to claim 1 or 7, characterized in that, The value adjustment material is one or more of ammonium bicarbonate, sodium carbonate, ammonia, and sodium hydroxide, or by-products produced in the system, including sodium hydroxide waste water, by-product ammonia, or sodium carbonate.

9. The process of reducing the loss of rare earths by adjusting the value of rare earths in a rare earth solution containing phosphorus by using the iron dephosphorization and segmented value adjustment method according to claim 1, characterized in that, In step (7), the primary value adjustment solution is heated to above 80℃, and the secondary value adjustment endpoint pH is 4.5-5.

10. The process of reducing the loss of rare earths by adjusting the value of rare earths in a rare earth solution containing phosphorus by using the iron dephosphorization and segmented value adjustment method according to claim 1, characterized in that, The primary value adjustment residue obtained in step (6) has low rare earth content and high iron phosphate content, and is used for further recovery of valuable elements of iron and phosphorus; and the secondary value adjustment residue obtained in step (8) is used for further extraction of rare earth.

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