Organic dispersant for preparing phosphoric acid from phosphate rock and its preparation method

Abstract

The application relates to the technical field of wet-process phosphoric acid production, in particular to an organic dispersant for preparing phosphoric acid from phosphate ore and a preparation method thereof. The preparation method comprises the following steps: under nitrogen protection, 2-acrylamide-2-methylpropane sulfonic acid is taken out and stirred in deionized water, acrylamide is added and continuously stirred, acrylic acid and methoxy polyethylene glycol acrylate are added, the pH value is adjusted, EDTA-2Na is added and continuously stirred, and standing is carried out, so as to obtain a mixed solution A; under nitrogen protection, the mixed solution A is heated to 40-45 DEG C, ammonium persulfate and sodium bisulfite are added and stirred, cooling is carried out, hydroquinone is added and continuously stirred, recooling is carried out, the pH value is adjusted, deionized water is added, and filtration is carried out, so as to obtain an organic dispersant for preparing phosphoric acid from phosphate ore. The organic dispersant for preparing phosphoric acid from phosphate ore and the preparation method thereof can improve the filtering performance of phosphogypsum, improve the P2O5 recovery rate and delay scaling.

Description

Technical Field

[0001] This application relates to the field of wet-process phosphoric acid production technology, specifically to an organic dispersant for preparing phosphoric acid from phosphate rock and its preparation method. Background Technology

[0002] Wet-process phosphoric acid is a core intermediate product in the phosphorus chemical industry, with over 85% of global phosphoric acid production using this method. Currently, the dihydrate process is widely used industrially: phosphate rock is reacted with excess sulfuric acid in an extraction tank to produce phosphoric acid and calcium sulfate dihydrate crystals. The resulting phosphogypsum crystals are separated by a vacuum filter to obtain dilute phosphoric acid, while the phosphogypsum is discharged as a filter cake. The efficiency of the filtration section directly affects phosphoric acid production capacity and costs. However, the dihydrate wet-process phosphoric acid production faces the following challenges: the phosphogypsum crystals formed during the reaction are mostly fine plate-like or needle-like microcrystals. In strong acid and high ionic strength media, the double layer on the microcrystal surface is severely compressed, and van der Waals forces dominate, causing the microcrystals to rapidly aggregate into dense flocs with low porosity. These flocs form high-resistance filter cakes on the filter, reducing the filtration rate, increasing the filter cake moisture content, and causing a large amount of P2O5 to be lost with the filter cake, resulting in a lower recovery rate. Furthermore, the Mg2+ associated with the phosphate rock... 2+ Fe 3+ Al 3+ When metal ions dissolve under acidic conditions, they form colloidal phosphate precipitates with phosphate ions and metal bridges on the surface of gypsum microcrystals, exacerbating particle adhesion. Furthermore, fluorosilicates crystallize and deposit on the walls and filter screens, leading to severe scaling, shortened cleaning cycles, and frequent maintenance shutdowns. Therefore, there is an urgent need to develop an organic dispersant that can stably perform its dispersing function under the extreme media conditions of wet-process phosphoric acid, while also possessing electrostatic repulsion, steric hindrance, and metal ion chelation functions, to improve the filtration performance of phosphogypsum, increase P2O5 recovery, and delay scaling. Summary of the Invention

[0003] To address the aforementioned issues, the purpose of this application is to provide an organic dispersant for preparing phosphoric acid from phosphate rock and its preparation method, so as to improve the filtration performance of phosphogypsum, increase the P2O5 recovery rate, and delay scaling.

[0004] To achieve the above objectives, this application provides a method for preparing an organic dispersant for phosphoric acid production from phosphate rock, comprising the following steps:

[0005] S1. Under nitrogen protection throughout the process, add 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir. Add acrylamide and continue stirring. Add acrylic acid and methoxy polyethylene glycol acrylate, adjust the pH value, add EDTA-2Na and continue stirring. Let stand to obtain mixture A.

[0006] S2. Under nitrogen protection throughout the process, heat the mixture A to 40-45℃, add ammonium persulfate and sodium bisulfite, stir, cool down, add hydroquinone and continue stirring, cool down again, adjust the pH value, add deionized water, filter, and obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

[0007] In the above process, ammonium persulfate reacts with sodium bisulfite to produce SO4. - • Free radicals react with double bonds to cause chain growth, and the reaction ends under the action of hydroquinone to form copolymers.

[0008] Furthermore, the acrylamide has a molar ratio of 2.5-4.8 to 1.1-1.9 with 2-acrylamido-2-methylpropanesulfonic acid.

[0009] Furthermore, the acrylic acid has a molar ratio of 3.5-5.8 to 1.1-1.9 with 2-acrylamide-2-methylpropanesulfonic acid.

[0010] Furthermore, the molar ratio of the methoxy polyethylene glycol acrylate to 2-acrylamide-2-methylpropanesulfonic acid is 0.46-0.91:1.1-1.9.

[0011] Furthermore, the stirring in step S1 is performed at a speed of 200-300 rpm.

[0012] Furthermore, in step S1, the pH value is adjusted to 5.2-5.8.

[0013] Furthermore, the mass ratio of EDTA-2Na to ammonium persulfate is 1:6-16.

[0014] Furthermore, the ammonium persulfate accounts for 0.6-1% of the total mass of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, acrylic acid, and methoxy polyethylene glycol acrylate.

[0015] Furthermore, the sodium bisulfite has a mass ratio of sodium bisulfite to ammonium persulfate of 0.45-0.55:1.

[0016] Furthermore, the hydroquinone has a mass ratio of 1:12-32 to ammonium persulfate.

[0017] Furthermore, step S2 involves adjusting the pH value to 3.5-4.5.

[0018] This application also provides a method for preparing an organic dispersant for preparing phosphoric acid from phosphate rock, and the organic dispersant prepared from the phosphate rock is described.

[0019] In summary, this application has the following beneficial effects:

[0020] This application discloses an organic dispersant for preparing phosphoric acid from phosphate rock, using acrylic acid as one of the main monomers. It provides carboxylate structural units: these units serve as both the backbone carbon and provide a large amount of carboxylic acid and carboxylate negative charge, competing with calcium, magnesium, and iron ions for complexation. This results in high activity and low cost in copolymerization reactions. Acrylic acid allows the dispersant to maintain particle repulsion in the phosphoric acid medium through the electrostatic repulsion of carboxylate groups. The chelation competition of carboxylic acid groups with metal ions weakens the tendency for metal bridges and colloidal phosphates and fluorosilicates to adhere more easily to the surface, which is beneficial. The filter cake is more porous and scaling is slower. 2-Acrylamide-2-methylpropanesulfonic acid, as one of the main monomers, provides a strong sulfonate group. Simultaneously, the amide and quaternary carbon in its structure contribute to better water solubility and salt resistance. The sulfonate group has a stronger anchoring affinity for the gypsum surface, forming a strong electrostatic adsorption with the exposed calcium ion sites on the gypsum crystal surface. This adsorption preempts sites where gypsum crystals would normally adsorb water molecules or other aggregates, effectively hindering further growth and aggregation of gypsum crystals, helping the dispersant to stably disperse gypsum particles. Meanwhile, the sulfonic acid... The spatial structure of the groups can better fit the atomic arrangement of the gypsum crystal surface; acrylamide, as the third main monomer, provides amide groups, which can provide weak hydrogen-bonded adsorption and adjust the flexibility of the main chain and hydrophilic balance. The chains of acrylic acid and 2-acrylamide-2-methylpropanesulfonic acid are too hard and too strongly charged, and are prone to adsorption conformation shrinkage and uneven coverage under high ionic strength. Acrylamide allows the polymer to adhere to the surface of mineral powder and gypsum microcrystals like a spreadable soft film, rather than relying solely on long-distance charge repulsion, reducing the system's dependence on carboxylic acid groups and reducing the influence of excessive local calcium ions. The anomalous adsorption is caused by methoxy polyethylene glycol acrylate, a polyether macromonomer. Its double bonds are incorporated into the main chain, linking a methoxy-terminated polyethylene glycol side chain to form a comb-like structure. This provides steric hindrance, preventing particles from approaching each other. The oxygen on the ether bonds can form a hydrogen bond network with water, creating a thicker hydration layer and a three-dimensional shell near the interface for each side chain. This reduces the contact probability of gypsum microcrystals, making the fine crystals less prone to agglomeration, resulting in a smoother apparent viscosity, more dispersed slurry, a looser filter cake, and a more stable filtration rate. Ammonium persulfate is used as an initiator, S2O8... 2- It can homolytically split to produce SO4 -• Free radicals initiate monomer polymerization; sodium bisulfite, as a reducing component, forms a redox initiation pair with ammonium persulfate, ensuring stable reaction even at low temperatures; EDTA-2Na acts as a metal chelating agent, binding trace amounts of transition metals such as iron and copper ions, reducing their abnormal catalytic decomposition of persulfate; hydroquinone acts as a free radical inactivator, locking the reaction system to prevent further polymerization during storage and transportation due to the activation of trace initiation potential by light, heat, or metals; this application utilizes acrylic acid, acrylamide, and 2-acrylamide-2- Methylpropanesulfonic acid's acid resistance and chelating framework provide surface anchoring and competition with metal ions. Combined with the comb-shaped hydration side chains introduced by methoxy polyethylene glycol acrylate, it provides salt-insensitive steric hindrance. Through redox aqueous copolymerization, partial neutralization, chain transfer control, inert protection, and terminal inactivation, this comb-shaped dispersant is made into a low-residue, pumpable, stable liquid. This results in more stable slurry dispersion, looser phosphogypsum filter cake, better filtration rate and P2O5 recovery, and reduced scaling and cleaning frequency. Furthermore, the process route is mild in the aqueous phase, the parameters can be closed-loop, and it is suitable for industrial scale-up. Detailed Implementation

[0021] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this invention.

[0022] The raw materials involved in the specific embodiments of this application are analytical grade. In addition, acrylic acid was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., No. A103525; 2-acrylamide-2-methylpropanesulfonic acid was purchased from Nantong Herun Biotechnology Co., Ltd., No. HR2234; acrylamide was purchased from Shandong Shuojia Chemical Co., Ltd., No. A00001; and methoxy polyethylene glycol acrylate was purchased from Shanghai Yuanye Biotechnology Co., Ltd., No. S28711.

[0023] Example 1

[0024] A method for preparing an organic dispersant for phosphoric acid production from phosphate rock includes the following steps:

[0025] S1. Under nitrogen protection throughout the process, add 310g of 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir (200rpm) for 15 minutes. Add 180g of acrylamide and continue stirring for 10 minutes. Add 250g of acrylic acid and 160g of methoxy polyethylene glycol acrylate. Adjust the pH to 5.2 using 30wt% sodium hydroxide solution. Add 1g of EDTA-2Na and stir for 5 minutes. Let stand for 5 minutes to obtain mixture A.

[0026] S2. Under nitrogen protection throughout the process, heat mixture A to 40°C at a heating rate of 1°C / min, add 6g of ammonium persulfate and 3g of sodium bisulfite, and stir at 200rpm for 50 minutes. Cool down to 30°C, add 0.5g of hydroquinone, and continue stirring for 10 minutes. Cool down to 20°C, stop the nitrogen flow, adjust the pH to 3.5 with 10wt% dilute sulfuric acid or sodium hydroxide solution, add deionized water to bring the solid content to 20%, and filter with a 200-mesh nylon filter cloth to obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

[0027] Example 2

[0028] A method for preparing an organic dispersant for phosphoric acid production from phosphate rock includes the following steps:

[0029] S1. Under nitrogen protection throughout the process, add 420g of 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir (250rpm) for 15 minutes. Add 310g of acrylamide and continue stirring for 10 minutes. Add 285g of acrylic acid and 240g of methoxy polyethylene glycol acrylate. Adjust the pH to 5.5 using 30wt% sodium hydroxide solution. Add 1g of EDTA-2Na and stir for 5 minutes. Let stand for 5 minutes to obtain mixture A.

[0030] S2. Under nitrogen protection throughout the process, the mixture A is heated to 43°C at a heating rate of 1°C / min. 11g of ammonium persulfate and 5.5g of sodium bisulfite are added and stirred at 250rpm for 50 minutes. The mixture is then cooled to 30°C, 0.5g of hydroquinone is added, and stirring is continued for 10 minutes. The mixture is then cooled to 23°C, and nitrogen gas is stopped. The pH is adjusted to 4 with 10wt% dilute sulfuric acid or sodium hydroxide solution. Deionized water is added until the solid content reaches 20%. The mixture is then filtered through a 200-mesh nylon filter cloth to obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

[0031] Example 3

[0032] A method for preparing an organic dispersant for phosphoric acid production from phosphate rock includes the following steps:

[0033] S1. Under nitrogen protection throughout the process, add 540g of 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir (300rpm) for 15 minutes. Add 340g of acrylamide and continue stirring for 10 minutes. Add 420g of acrylic acid and 320g of methoxy polyethylene glycol acrylate. Adjust the pH to 5.8 using 30wt% sodium hydroxide solution. Add 1g of EDTA-2Na and stir for 5 minutes. Let stand for 5 minutes to obtain mixture A.

[0034] S2. Under nitrogen protection throughout the process, the mixture A is heated to 45°C at a heating rate of 1.5°C / min. 16.2g of ammonium persulfate and 8.1g of sodium bisulfite are added and stirred at 300rpm for 50 minutes. The mixture is then cooled to 30°C, 0.5g of hydroquinone is added, and stirring is continued for 10 minutes. The mixture is then cooled to 25°C, and nitrogen gas is stopped. The pH is adjusted to 4.5 with 10wt% dilute sulfuric acid or sodium hydroxide solution. Deionized water is added until the solid content reaches 20%. The mixture is then filtered through a 200-mesh nylon filter cloth to obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

[0035] Compare with Example 1

[0036] The difference between this comparative example and Example 3 is that the method for preparing an organic dispersant for phosphoric acid production from phosphate rock in this comparative example includes the following steps:

[0037] S1. Under nitrogen protection throughout the process, add 540g of 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir (300rpm) for 15 minutes. Add 340g of acrylamide and continue stirring for 10 minutes. Add 740g of acrylic acid and adjust the pH to 5.8 using 30wt% sodium hydroxide solution. Add 1g of EDTA-2Na and stir for 5 minutes. Let stand for 5 minutes to obtain mixture A.

[0038] S2. Under nitrogen protection throughout the process, the mixture A is heated to 45°C at a heating rate of 1.5°C / min. 16.2g of ammonium persulfate and 8.1g of sodium bisulfite are added and stirred at 300rpm for 50 minutes. The mixture is then cooled to 30°C, 0.5g of hydroquinone is added, and stirring is continued for 10 minutes. The mixture is then cooled to 25°C, and nitrogen gas is stopped. The pH is adjusted to 4.5 with 10wt% dilute sulfuric acid or sodium hydroxide solution. Deionized water is added until the solid content reaches 20%. The mixture is then filtered through a 200-mesh nylon filter cloth to obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

[0039] Compare with Example 2

[0040] The difference between this comparative example and Example 3 is that the method for preparing an organic dispersant for phosphoric acid production from phosphate rock in this comparative example includes the following steps:

[0041] S1. Under nitrogen protection throughout the process, add 880g of 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir (300rpm) for 15 minutes. Add 420g of acrylic acid and 320g of methoxy polyethylene glycol acrylate. Adjust the pH to 5.8 using 30wt% sodium hydroxide solution. Add 1g of EDTA-2Na and stir for 5 minutes. Let stand for 5 minutes to obtain mixture A.

[0042] S2. Under nitrogen protection throughout the process, the mixture A is heated to 45°C at a heating rate of 1.5°C / min. 16.2g of ammonium persulfate and 8.1g of sodium bisulfite are added and stirred at 300rpm for 50 minutes. The mixture is then cooled to 30°C, 0.5g of hydroquinone is added, and stirring is continued for 10 minutes. The mixture is then cooled to 25°C, and nitrogen gas is stopped. The pH is adjusted to 4.5 with 10wt% dilute sulfuric acid or sodium hydroxide solution. Deionized water is added until the solid content reaches 20%. The mixture is then filtered through a 200-mesh nylon filter cloth to obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

[0043] Compare with Example 3

[0044] The difference between this comparative example and Example 3 is that the method for preparing an organic dispersant for phosphoric acid production from phosphate rock in this comparative example includes the following steps:

[0045] S1. Under nitrogen protection throughout the process, add 540g of 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir (300rpm) for 15 minutes. Add 340g of acrylamide and continue stirring for 10 minutes. Add 420g of acrylic acid and 320g of methoxy polyethylene glycol acrylate. Adjust the pH to 5.8 using 30wt% sodium hydroxide solution. Add 1g of EDTA-2Na and stir for 5 minutes. Let stand for 5 minutes to obtain mixture A.

[0046] S2. Under nitrogen protection throughout the process, the mixture A is heated to 60°C at a heating rate of 1.5°C / min. 16.2g of ammonium persulfate and 8.1g of sodium bisulfite are added and stirred at 300rpm for 50 minutes. The mixture is then cooled to 30°C, 0.5g of hydroquinone is added, and stirring is continued for 10 minutes. The mixture is then cooled to 25°C, and nitrogen gas is stopped. The pH is adjusted to 4.5 with 10wt% dilute sulfuric acid or sodium hydroxide solution. Deionized water is added until the solid content reaches 20%. The mixture is then filtered through a 200-mesh nylon filter cloth to obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

[0047] Performance testing

[0048] The organic dispersants for preparing phosphoric acid from phosphate rock prepared in Examples 1-3 and Control Examples 1-3 were subjected to functional tests.

[0049] Static sedimentation test: Prepare a 20wt% P2O5 solution, weigh 9.60g of dry equivalent gypsum, add it to a 150mL tall beaker, then add 70.4g of 20wt% P2O5 solution, stir at 400rpm for 2min, add 96μL of organic dispersant for preparing phosphoric acid from phosphate rock diluted 10 times, stir at 900rpm for 60s, take a 100mL graduated sedimentation cylinder, pour the entire 80g slurry into the cylinder within 10s, immediately place the cylinder in a vertical, vibration-free, backlit place, observe the sedimentation state, and record the mudline height after 60 minutes;

[0050] Filtration rate test: Prepare a 20wt% P2O5 solution, weigh 64g of dry basis equivalent gypsum, add 136g of 20wt% P2O5 solution to a beaker, add 64g of dry basis equivalent gypsum and stir at 400rpm for 3min, add 0.128mL of organic dispersant for phosphoric acid preparation from phosphate rock, stir at 800rpm for 90s, quickly pour into a funnel, gently scrape the beaker wall with a glass rod to transfer the entire volume, gently scrape the surface with a scraper, read the filtrate volume every 10s until the filtrate increases by <0.2mL / min and stop filtration, use a scraper to take the whole filter cake into a known weight aluminum box, weigh it W1, dry at 105℃ for 2h to constant weight, weigh it W2, calculate the water content of the filter cake = (W1-W2) / W1×100%, record the filtration rate in L / m²·min;

[0051] The results are shown in Table 1:

[0052] Table 1

[0053] Group Mudline height Depositional state Filtration rate Filter cake moisture content % Example 1 46mL Loose, scrapable, and non-reflective 8.8 23 Example 2 52mL Loose, scrapable, and non-reflective 9.7 22 Example 3 48mL Loose, scrapable, and non-reflective 9.5 22 Compare with Example 1 32mL Harder, semi-reflective clay-like texture 5.6 30 Compare with Example 2 34mL Localized hard lumps, uneven distribution 5.1 33 Compare with Example 3 28mL Hard, reflective clay, with microgel particles 4.2 35

[0054] As shown in Table 1, the dispersant prepared in this application settles more slowly, deposits more loosely, filters faster, and produces a drier filter cake, indicating that the dispersant prepared in this application can effectively disperse phosphogypsum microcrystals in a strong acid and high salt wet-process phosphoric acid system. Compared with Example 3, Comparative Example 1 uses acrylic acid instead of methoxy polyethylene glycol acrylate, which loses the steric hindrance of the comb-shaped side chains. In the high ionic strength phosphoric acid medium, pure electrostatic repulsion is severely compressed, and van der Waals attraction between particles becomes dominant, leading to rapid aggregation of microcrystals. Although there are more carboxyl groups, most of them are protonated in strong acid, resulting in limited electrostatic contribution and reduced performance. Compared with Example 3, Comparative Example 2 uses 2-acrylamido-2-methylpropanesulfonic acid instead of acrylamide. The loss of acrylamide makes the polymer backbone stiff and difficult to disperse in rough phosphoric acid. The uniform spreading of the paste crystals makes it prone to point adsorption-bridging reversal. Without the weak adsorption assistance of acrylamide hydrogen bonding, the polymer tends to have strong local adsorption, resulting in incomplete coverage of the particle surface. The uncovered areas are prone to direct contact flocculation, leading to a decrease in dispersant performance. Compared with Example 3, the polymerization temperature of Comparative Example 3 was increased to 60°C. At 60°C, the redox pair of ammonium persulfate and sodium bisulfite generates active species at a much higher rate than at 45°C. This results in an excessively high concentration of instantaneous free radicals in the early stage, leading to short chains, reduced grafting rate, thin adsorption layer, insufficient steric hindrance, and rapid aggregation of microcrystals. The excessively high temperature also causes interchain crosslinking to form microgels, resulting in insoluble microparticles in the product. These microparticles clog the filter cake pores in the filtration test, causing a sharp drop in filtration rate and a decrease in performance.

[0055] The above description is merely an example and illustration of the concept of this application. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the inventive concept or exceed the scope defined in the claims, they should all fall within the protection scope of this application.

Claims

1. A method for preparing an organic dispersant for phosphoric acid production from phosphate rock, characterized in that, Includes the following steps: S1. Under nitrogen protection throughout the process, add 2-acrylamide-2-methylpropanesulfonic acid to deionized water and stir. Add acrylamide and continue stirring. Add acrylic acid and methoxy polyethylene glycol acrylate, adjust the pH value, add EDTA-2Na and continue stirring. Let stand to obtain mixture A. S2. Under nitrogen protection throughout the process, heat the mixture A to 40-45℃, add ammonium persulfate and sodium bisulfite, stir, cool down, add hydroquinone and continue stirring, cool down again, adjust the pH value, add deionized water, filter, and obtain an organic dispersant for preparing phosphoric acid from phosphate rock.

2. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, The acrylamide has a molar ratio of 2.5-4.8 to 1.1-1.9 with 2-acrylamido-2-methylpropanesulfonic acid.

3. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, The acrylic acid has a molar ratio of 3.5-5.8 to 1.1-1.9 with 2-acrylamide-2-methylpropanesulfonic acid.

4. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, The methoxy polyethylene glycol acrylate has a molar ratio of 0.46-0.91 to 1.1-1.9 with 2-acrylamide-2-methylpropanesulfonic acid.

5. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, In step S1, the pH value is adjusted to 5.2-5.

8.

6. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, The mass ratio of EDTA-2Na to ammonium persulfate is 1:6-16.

7. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, The ammonium persulfate accounts for 0.6-1% of the total mass of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, acrylic acid, and methoxy polyethylene glycol acrylate.

8. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, The sodium bisulfite is wherein the mass ratio of sodium bisulfite to ammonium persulfate is 0.45-0.55:

1.

9. The method for preparing an organic dispersant for phosphoric acid production from phosphate rock according to claim 1, characterized in that, Step S2 involves adjusting the pH value to 3.5-4.

5.

10. An organic dispersant for preparing phosphoric acid from phosphate rock prepared by the method for preparing an organic dispersant for preparing phosphoric acid from phosphate rock as described in any one of claims 1-9.