Method for circularly preparing beta-tricalcium phosphate from recycled waste liquid

Abstract

The invention discloses a method for circularly preparing beta-tricalcium phosphate from recycled waste liquid, which comprises the following steps: 1) reacting a calcium source with a phosphorus source, aging and separating to obtain a beta-tricalcium phosphate precursor and filtrate; 2) drying and roasting the beta-tricalcium phosphate precursor to obtain beta-tricalcium phosphate powder; and 3) adding calcium oxide and a surfactant into the filtrate to obtain the calcium source in the step 1), then adding a phosphorus source to carry out the next reaction process, and recycling the filtrate in the repeated reaction process. The method for preparing beta-tricalcium phosphate by recycling the waste liquid is simple to operate, and effectively solves the problem of water circulation in the process of preparing beta-tricalcium phosphate.

Description

Technical Field

[0001] The invention relates to the technical field of medical material preparation, and in particular to a method for recycling waste liquid to prepare beta-tricalcium phosphate. Background Art

[0002] β-tricalcium phosphate has high biocompatibility, good bioabsorbability and bone growth induction, which has attracted the attention of many researchers. The biggest feature of β-tricalcium phosphate is that it is easily absorbed in the body. Its degradation rate in body fluids is 10-15 times that of hydroxyapatite, and it has excellent biodegradability. In addition, β-TCP will not affect the hematopoietic function of the bone marrow, has no toxic side effects, rejection reactions or allergic phenomena, will not cause cancer, and the dissolved Ca and P will also be absorbed by the new bone. It is a bone repair material with excellent performance.

[0003] The conventional chemical precipitation method for preparing β-tricalcium phosphate requires a large amount of production water. If the water cannot be recycled, it will cause a large waste of water resources, and the treatment of wastewater will also cost a high cost. If the wastewater is repeatedly fed with materials for experiments, some ions will be enriched, increasing production costs. The present invention provides a method for recycling waste liquid to prepare β-tricalcium phosphate, which does not cause ion enrichment and achieves the purpose of recycling wastewater. Summary of the invention

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A method for recycling waste liquid to prepare β-tricalcium phosphate comprises the following steps: 1) Using a calcium source and a phosphorus source to react, after aging and solid-liquid separation, a β-tricalcium phosphate precursor and a filtrate are obtained; 2) The β-tricalcium phosphate precursor is dried and calcined to obtain β-tricalcium phosphate powder; 3) Calcium oxide is added to the filtrate to obtain the calcium source in step 1) for recycling.

[0005] In the step 1), the calcium source may be calcium nitrate tetrahydrate, calcium chloride, calcium hydroxide, calcium carbonate, calcium oxide, calcium acetate, calcium sulfate, etc.; the phosphorus source may be diammonium phosphate, diammonium hydrogen phosphate, phosphoric acid, trisodium phosphate, etc., wherein the molar ratio of the calcium source to the phosphorus source is 1.50; The reaction solvent of the calcium source and the phosphorus source in step 1) is a mixture of deionized water and alcohols, wherein the proportion of the alcohol compound is 20% to 80%, and the alcohol compound includes one or more of methanol, ethanol, propanol, isopropanol, n-butanol, and isobutanol; In the step 1), a surfactant and an ionic strength regulator are added to the reaction solvent of the calcium source and the phosphorus source. The surfactant includes one or more of sodium fatty acid methyl ester sulfonate, sodium taurocholate, benzalkonium chloride, rose red ammonium tricarboxylate, sodium catechol-3,5-disulfonate, and sodium diethyldithiocarbamate; and the ionic strength regulator includes one or more of carbonate, nitrate, chloride, sulfide, fluoride, acetate, oxalate, citrate, phosphate, pyrophosphate, and tartrate of sodium, potassium, ammonium, magnesium, and aluminum ions.

[0006] In the step 1), the pH is adjusted by using alkaline reagents such as ammonia water, sodium hydroxide, triethanolamine, etc., and the reaction pH value is adjusted to 7-9.

[0007] In the step 1), the reaction temperature is 20-95°C, the reaction time is 4-8h, the reaction is complete, the aging time is 4-24h, the solid-liquid separation method is suction filtration or centrifugal separation; the sample drying method is atmospheric pressure drying, the drying temperature is 60-180°C; the sample calcination temperature is 800-1000°C, and the calcination time is 2h.

[0008] The amount of calcium oxide added in step 3) must be equal to the calcium content in the calcium source, and the amount of calcium oxide and phosphorus source added remains unchanged during the circulation process.

[0009] Compared with the prior art, the method for recycling waste liquid to prepare β-tricalcium phosphate according to the present invention has the following advantages: 1. The present invention adopts a conventional chemical precipitation method to prepare β-tricalcium phosphate, recycles the waste liquid after the primary reaction, adds calcium oxide and stirs it fully to form a calcium source, which continues to react with the added phosphorus source, and β-tricalcium phosphate can be continuously prepared. This process fundamentally solves the problem of water circulation in the chemical precipitation method, and at the same time reduces the enrichment of anions in the added calcium source, which can greatly reduce the production cost.

[0010] 2. The β-tricalcium phosphate prepared by the present invention has high purity, good crystallinity, good dispersibility, and stable performance, and has broad application prospects in the field of bone tissue engineering materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is the XRD pattern of β-tricalcium phosphate prepared in the second cycle in Example 1 of the present invention.

[0012] Figure 2 This is a SEM image of β-tricalcium phosphate prepared in the second cycle in Example 1 of the present invention.

[0013] Figure 3 This is a particle size distribution diagram of β-tricalcium phosphate prepared in the second cycle in Example 1 of the present invention. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0015] Example 1 (1) Take 50 ml of methanol, 50 ml of ethanol, and 200 ml of deionized water, mix them evenly, add 1 g of sodium fatty acid methyl ester sulfonate and 1.5 g of sodium citrate, stir evenly, then add 0.06 mol of calcium nitrate tetrahydrate to dissolve, and obtain a calcium source solution; take another 50 ml of methanol, 50 ml of isobutyl alcohol, and 200 ml of deionized water, mix them evenly, add 0.04 mol of diammonium hydrogen phosphate and stir evenly, and obtain a phosphorus source solution. Add the phosphorus source solution dropwise into the calcium source solution, stir at room temperature for 6 h, add ammonia water to adjust the reaction pH to 8 during the reaction, let it stand for 10 h, and then use suction filtration for solid-liquid separation. Wash the solid three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor.

[0016] (2) The β-tricalcium phosphate precursor was placed in a 120 ℃ oven and dried at normal pressure for 12 h. It was then kept at 900 ℃ in a muffle furnace for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate powder with a D50 of 14.67 μm.

[0017] (3) 0.06 mol calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.04 mol diammonium hydrogen phosphate was added. The reaction was stirred at room temperature for 8 hours. During the reaction, ammonia water was added to adjust the reaction pH to 8. After standing for 15 hours, the solid-liquid separation was carried out by suction filtration. The solid was washed with water three times and with anhydrous ethanol three times to obtain a β-tricalcium phosphate precursor. The precursor was placed in a 120°C oven and dried at normal pressure for 12 hours. Then, the precursor was kept at 900°C in a muffle furnace for 2 hours. The heating rate was controlled at 5°C / min to obtain a β-tricalcium phosphate powder (the XRD pattern of the β-tricalcium phosphate powder is as follows: Figure 1 As shown, SEM Figure 2 The particle size distribution diagram is shown in Figure 3 As shown. ), the filtrate enters the next cycle as mother liquor.

[0018] Example 2 (1) Take 50 ml of ethanol, 50 ml of n-butanol, and 200 ml of deionized water, mix them evenly, add 1 g of sodium diethyldithiocarbamate and 1 g of sodium chloride, stir evenly, then add 0.06 mol of calcium chloride to dissolve and obtain a calcium source solution; take another 50 ml of ethanol, 50 ml of n-butanol, and 200 ml of deionized water, mix them evenly, add 0.04 mol of diammonium hydrogen phosphate and stir evenly to obtain a phosphorus source solution. Add the phosphorus source solution dropwise into the calcium source solution, stir at room temperature for 4 h, add triethanolamine during the reaction to adjust the reaction pH to 9, let it stand for 6 h, and then use suction filtration for solid-liquid separation. Wash the solid three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor.

[0019] (2) The β-tricalcium phosphate precursor was placed in a 100 ℃ oven and dried for 12 h. It was then kept in a muffle furnace at 800 ℃ for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate powder with a D50 of 18.84 μm.

[0020] (3) 0.06 mol calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.04 mol ammonium dihydrogen phosphate was added. The mixture was stirred at room temperature for 8 h. During the reaction, ammonia water was added to adjust the pH value of the reaction to 9. After standing for 15 h, the solid-liquid separation was performed by suction filtration. The solid was washed three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor. The precursor was placed in a 100 °C oven and dried for 12 h. The precursor was then kept at 800 °C in a muffle furnace for 2 h. The heating rate was controlled at 5 °C / min to obtain a β-tricalcium phosphate powder with a D50 of 22.59 μm. The filtrate was used as the mother liquor for the next cycle.

[0021] Example 3 (1) Take 50 ml of ethanol, 50 ml of isopropanol, and 200 ml of deionized water, mix them evenly, add 1 g of sodium catechol-3,5-disulfonate and 1.5 g of sodium citrate, stir evenly, and then add 0.09 mol of calcium oxide to obtain a calcium source solution; take another 50 ml of ethanol, 50 ml of isopropanol, and 200 ml of deionized water, mix them evenly, add 0.06 mol of phosphoric acid and stir evenly to obtain a phosphorus source solution. Drop the phosphorus source solution into the calcium source turbid solution, stir at room temperature for 6 h, add ammonia water to adjust the reaction pH to 7 during the reaction, stand for 15 h, and then use suction filtration for solid-liquid separation. The solid is washed with water three times and with anhydrous ethanol three times to obtain a β-tricalcium phosphate precursor.

[0022] (2) The β-tricalcium phosphate precursor was placed in a 60 ℃ oven and dried at normal pressure for 18 h. It was then kept in a muffle furnace at 1000 ℃ for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate powder with a D50 of 20.89 μm.

[0023] (3) 0.09 mol calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.06 mol phosphoric acid was added. The mixture was stirred at room temperature for 8 h. During the reaction, ammonia water was added to adjust the pH value of the reaction to 7. After standing for 15 h, the solid-liquid separation was performed by suction filtration. The solid was washed with water three times and with anhydrous ethanol three times to obtain a β-tricalcium phosphate precursor. The precursor was placed in a 60°C oven and dried at normal pressure for 18 h. The precursor was then kept in a muffle furnace at 1000°C for 2 h. The heating rate was controlled at 5°C / min to obtain a β-tricalcium phosphate powder with a D50 of 22.77 μm. The filtrate was used as the mother liquor for the next cycle.

[0024] Example 4 (1) Take 100 ml of ethanol, 100 ml of isobutanol, and 100 ml of deionized water, mix them evenly, add 1.5 g of sodium taurocholate and 1 g of potassium oxalate, stir evenly, and then add 0.09 mol of calcium hydroxide to obtain a calcium source solution; take another 100 ml of ethanol, 100 ml of isobutanol, and 100 ml of deionized water, mix them evenly, add 0.06 mol of phosphoric acid and stir evenly to obtain a phosphorus source solution. Drop the phosphorus source solution into the calcium source turbid solution, stir at room temperature for 6 h, add ammonia water to adjust the reaction pH to 8 during the reaction, stand for 15 h, and then use suction filtration for solid-liquid separation. The solid is washed with water three times and with anhydrous ethanol three times to obtain a β-tricalcium phosphate precursor.

[0025] (2) The β-tricalcium phosphate precursor was placed in an 80 ℃ oven and dried at normal pressure for 12 h. It was then kept in a muffle furnace at 900 ℃ for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate powder with a D50 of 16.57 μm.

[0026] (3) 0.09 mol calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.06 mol phosphoric acid was added. The mixture was stirred at room temperature for 8 h. During the reaction, aqueous ammonia was added to adjust the pH value of the reaction to 8. The mixture was allowed to stand for 15 h. The solid-liquid separation was performed by suction filtration. The solid was washed with water three times and with anhydrous ethanol three times to obtain a β-tricalcium phosphate precursor. The precursor was placed in an oven at 80 °C and dried at normal pressure for 12 h. The precursor was then kept in a muffle furnace at 900 °C for 2 h. The heating rate was controlled at 5 °C / min to obtain a β-tricalcium phosphate powder with a D50 of 18.76 μm. The filtrate was used as the mother liquor for the next cycle.

[0027] Example 5 (1) Take 120 ml of ethanol, 120 ml of propanol, and 60 mL of deionized water and mix them evenly. Add 1 g of sodium diethyldithiocarbamate and 1.5 g of sodium acetate. Stir evenly and then add 0.09 mol of calcium carbonate to obtain a calcium source solution. Take another 120 ml of ethanol, 120 ml of propanol, and 60 mL of deionized water and mix evenly. Add 0.06 mol of phosphoric acid and stir evenly to obtain a phosphorus source solution. Add the phosphorus source solution dropwise into the calcium source turbid solution and stir at room temperature for 8 hours. During the reaction, add ammonia water to adjust the reaction pH to 9. After standing for 20 hours, use suction filtration for solid-liquid separation. Wash the solid three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor.

[0028] (2) The β-tricalcium phosphate precursor was placed in a 120 ℃ oven and dried at normal pressure for 12 h. It was then kept in a muffle furnace at 1000 ℃ for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate powder with a D50 of 12.62 μm.

[0029] (3) 0.09 mol calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.06 mol phosphoric acid was added. The mixture was stirred at room temperature for 8 h. During the reaction, aqueous ammonia was added to adjust the pH value of the reaction to 9. After standing for 15 h, the solid-liquid separation was performed by suction filtration. The solid was washed with water three times and with anhydrous ethanol three times to obtain a β-tricalcium phosphate precursor. The precursor was placed in a 120°C oven and dried at normal pressure for 12 h. The precursor was then kept in a muffle furnace at 1000°C for 2 h. The heating rate was controlled at 5°C / min to obtain a β-tricalcium phosphate powder with a D50 of 14.42 μm. The filtrate was used as the mother liquor for the next cycle.

[0030] Example 6 (1) Take 60 ml of ethanol, 60 ml of isopropanol, and 180 ml of deionized water and mix them evenly. Add 1 g of sodium fatty acid methyl ester sulfonate, 1 g of sodium taurocholate, and 1.5 g of sodium acetate. Stir evenly and then add 0.09 mol of calcium acetate to dissolve to obtain a calcium source solution. Take another 60 ml of ethanol, 60 ml of isopropanol, and 180 ml of deionized water and mix evenly. Add 0.06 mol of diammonium hydrogen phosphate and stir evenly to obtain a phosphorus source solution. Add the phosphorus source solution dropwise into the calcium source solution and stir at room temperature for 5 hours. During the reaction, add ammonia water to adjust the reaction pH to 8. After standing for 20 hours, centrifuge for solid-liquid separation. Wash the solid three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor.

[0031] (2) The β-tricalcium phosphate precursor was placed in a 100 ℃ oven and dried for 12 h. It was then kept in a muffle furnace at 900 ℃ for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate powder with a D50 of 20.70 μm.

[0032] (3) 0.06 mol of calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.04 mol of diammonium hydrogen phosphate was added. The mixture was stirred at room temperature for 8 h. During the reaction, ammonia water was added to adjust the pH value of the reaction to 8. After standing for 15 h, the mixture was centrifuged for solid-liquid separation. The solid was washed three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor. The precursor was dried in a 100 °C oven for 12 h, and then kept at 900 °C in a muffle furnace for 2 h. The heating rate was controlled at 5 °C / min to obtain a β-tricalcium phosphate powder with a D50 of 22.25 μm. The filtrate was used as the mother liquor for the next cycle.

[0033] Example 7 (1) Take 30 ml of ethanol, 30 ml of isopropanol, and 240 ml of deionized water and mix them evenly. Add 1 g of ammonium tricarboxylate, 1 g of sodium diethyldithiocarbamate, and 1 g of ammonium sulfate. Stir evenly and then add 0.09 mol of calcium sulfate dihydrate to obtain a calcium source solution. Take another 30 ml of ethanol, 30 ml of isopropanol, and 240 ml of deionized water and mix evenly. Add 0.06 mol of diammonium hydrogen phosphate and stir evenly to obtain a phosphorus source solution. Add the phosphorus source solution to the calcium source turbid solution and stir at 60 °C for 6 h. During the reaction, add ammonia water to adjust the reaction pH to 9. After standing for 10 h, use suction filtration for solid-liquid separation. Wash the solid three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor.

[0034] (2) The β-tricalcium phosphate precursor was placed in a 120 ℃ oven and dried for 12 h, and then kept at 800 ℃ in a muffle furnace for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate powder with a D50 of 20.84 μm.

[0035] (3) 0.06 mol of calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.04 mol of diammonium hydrogen phosphate was added. The mixture was stirred at room temperature for 8 h. During the reaction, ammonia water was added to adjust the pH value of the reaction to 9. After standing for 15 h, the solid-liquid separation was performed by suction filtration. The solid was washed three times with water and three times with anhydrous ethanol to obtain a β-tricalcium phosphate precursor. The precursor was dried in a 120°C oven for 12 h, and then kept at 800°C in a muffle furnace for 2 h. The heating rate was controlled at 5°C / min to obtain a β-tricalcium phosphate powder with a D50 of 21.56 μm. The filtrate was used as the mother liquor for the next cycle.

[0036] Comparative Example 1 (1) Take 50 ml of ethanol, 50 ml of isopropanol, and 200 ml of deionized water, mix them evenly, add 1.5 g of sodium sulfate of fatty alcohol polyoxyethylene ether, 1.5 g of sodium dodecyl sulfate, stir evenly, and then add 0.09 mol of calcium oxide to obtain a calcium source solution; take another 50 ml of ethanol, 50 ml of isopropanol, and 200 ml of deionized water, mix them evenly, add 0.06 mol of phosphoric acid and stir evenly to obtain a phosphorus source solution. Drop the phosphorus source solution into the calcium source turbid solution, stir at room temperature for 6 h, add ammonia water to adjust the reaction pH to 10 during the reaction, stand for 15 h, and then use suction filtration for solid-liquid separation. The solid is washed with water three times and with anhydrous ethanol three times to obtain β-tricalcium phosphate and hydroxyapatite precursors.

[0037] (2) The β-tricalcium phosphate precursor was placed in a 60 ℃ oven and dried at normal pressure for 18 h, and then kept at 900 ℃ in a muffle furnace for 2 h. The heating rate was controlled at 5 ℃ / min to obtain a mixture of β-tricalcium phosphate and hydroxyapatite powder with a D50 of 16.19 μm.

[0038] (3) 0.09 mol calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.06 mol phosphoric acid was added. The mixture was stirred at room temperature for 8 h. During the reaction, ammonia water was added to adjust the reaction pH to 10. After standing for 15 h, the solid-liquid separation was performed by suction filtration. The solid was washed with water three times and with anhydrous ethanol three times to obtain β-tricalcium phosphate and hydroxyapatite precursors. The precursors were placed in a 60°C oven and dried at normal pressure for 18 h. The precursors were then kept in a muffle furnace at 900°C for 2 h. The heating rate was controlled at 5°C / min to obtain a mixture of β-tricalcium phosphate and 3.1% hydroxyapatite powder with a D50 of 18.76 μm. The filtrate was used as the mother liquor for the next cycle.

[0039] Comparative Example 2 (1) Take 100 ml of ethanol, 100 ml of propanol, and 100 ml of deionized water, mix them evenly, add 2 g of sodium sulfate of fatty alcohol polyoxyethylene ether, stir evenly, and then add 0.09 mol of calcium carbonate to obtain a calcium source solution; take another 100 ml of ethanol, 100 ml of propanol, and 100 ml of deionized water, mix them evenly, add 0.06 mol of phosphoric acid and stir evenly to obtain a phosphorus source solution. Drop the phosphorus source solution into the calcium source turbid solution, stir at room temperature for 8 hours, add ammonia water to adjust the reaction pH to 6 during the reaction, stand for 20 hours, and then use suction filtration for solid-liquid separation. The solid is washed with water three times and anhydrous ethanol three times to obtain β-tricalcium phosphate and calcium pyrophosphate precursors.

[0040] (2) The β-tricalcium phosphate precursor was placed in a 120 ℃ oven and dried at normal pressure for 12 h, and then kept at 900 ℃ in a muffle furnace for 2 h. The heating rate was controlled at 5 ℃ / min to obtain β-tricalcium phosphate and calcium pyrophosphate powders with a D50 of 28.94 μm.

[0041] (3) 0.09 mol calcium oxide was added to the filtered liquid in step (1), and after stirring, 0.06 mol phosphoric acid was added. The mixture was stirred at room temperature for 8 h. During the reaction, ammonia water was added to adjust the pH value of the reaction to 6. After standing for 15 h, the solid-liquid separation was performed by suction filtration. The solid was washed with water three times and with anhydrous ethanol three times to obtain β-tricalcium phosphate and calcium pyrophosphate precursors. The precursors were placed in a 120°C oven and dried at normal pressure for 12 h. The precursors were then kept in a muffle furnace at 900°C for 2 h. The heating rate was controlled at 5°C / min to obtain β-tricalcium phosphate and calcium pyrophosphate powder containing 5.2% of calcium pyrophosphate. The D50 was 29.03 μm. The filtrate was used as the mother liquor for the next cycle.

Claims

1. A method for recycling waste liquid to prepare β-tricalcium phosphate, characterized in that: include: 1) Using a calcium source and a phosphorus source to react, after aging and solid-liquid separation, a β-tricalcium phosphate precursor and a filtrate are obtained; 2) The β-tricalcium phosphate precursor is dried and calcined to obtain β-tricalcium phosphate powder; 3) Calcium oxide is added to the filtrate to obtain the calcium source in step 1) for recycling.

2. The method for preparing β-tricalcium phosphate by recycling waste liquid according to claim 1, characterized in that: In step 1), the calcium source is selected from any one of calcium nitrate tetrahydrate, calcium chloride, calcium hydroxide, calcium carbonate, calcium oxide, calcium acetate, and calcium sulfate; the phosphorus source is selected from any one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate, phosphoric acid, and trisodium phosphate, wherein the molar ratio of the calcium source to the phosphorus source is 1.

50.

3. The method for preparing β-tricalcium phosphate by recycling waste liquid according to claim 1, characterized in that: In step 1), the reaction solvent of the calcium source and the phosphorus source is a mixture of deionized water and alcohols, the proportion of the alcohol compound is 20% to 80%, and the alcohol compound includes one or more of methanol, ethanol, propanol, isopropanol, n-butanol, and isobutanol.

4. The method for preparing β-tricalcium phosphate by recycling waste liquid according to claim 1, characterized in that: In step 1), a surfactant and an ionic strength regulator are added to the reaction solvent of the calcium source and the phosphorus source. The surfactant includes one or more of sodium fatty acid methyl ester sulfonate, sodium taurocholate, benzalkonium chloride, rose red ammonium tricarboxylate, sodium catechol-3,5-disulfonate, and sodium diethyldithiocarbamate; the ionic strength regulator includes one or more of carbonate, nitrate, chloride, sulfide, fluoride, acetate, oxalate, citrate, phosphate, pyrophosphate, and tartrate of sodium, potassium, ammonium, magnesium, and aluminum ions.

5. The method for preparing β-tricalcium phosphate by recycling waste liquid according to claim 1, characterized in that: In step 1), the pH is adjusted using ammonia water, sodium hydroxide, and triethanolamine alkaline reagents to adjust the reaction pH value to 7-9.

6. The method for preparing β-tricalcium phosphate by recycling waste liquid according to claim 1, characterized in that: In step 1), the reaction temperature is 20-95° C., the reaction time is 4-8 hours, and the reaction is ensured to be complete. The aging time is 4-24 hours, and the solid-liquid separation method is suction filtration or centrifugal separation; the sample drying method is atmospheric pressure drying, and the drying temperature is 60-180° C.; the sample calcination temperature is 800-1000° C., and the calcination time is 2 hours.

7. The method for preparing β-tricalcium phosphate by recycling waste liquid according to claim 1, characterized in that: In step 3), the amount of calcium oxide added is equal to the calcium content in the calcium source, and the amount of calcium oxide and phosphorus source added remains unchanged during the circulation process.

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