Overview[1]
SrHPO4, DSPA) is an important chemical raw material and analytical reagent. It has been found to have broad application prospects in the fields of blue luminescent materials and all-solid-state micro lasers. SrHPO4 has three isomers: β-SrHPO4 formed at low temperature (structure similar to BaHPO4); α-SrHPO4 generated at high temperature (structure similar to the triclinic structure of CaHPO4) and Rohm and Haas resin synthesized by hydrothermal method. Hexagonal γ-SrHPO4 crystal (orthorhombic crystal system). Nanonization of SrHPO4 particles will not only expand its application in the fields of luminescent materials and lasers, but also help improve its solubility, laying the foundation for mixing with raw materials such as tetracalcium phosphate in the future to prepare strontium-containing bone cement with good performance. At present, although SrHPO4 is sold in domestic products, the particle size and particle size distribution do not meet the needs of research.
Apply[2-3]
As the main phosphor raw material, strontium hydrogen phosphate has great market prospects. Examples of its application are as follows:
1) Preparation of rare earth composite phosphors for three-band plant growth lamps, characterized in that the components of the rare earth composite phosphors include antioxidants 168 including strontium hydrogen phosphate, magnesium oxide, aluminum oxide, germanium oxide, and europium oxide , cerium oxide, and terbium oxide are the basic materials of the activator. The proportion of each component is: 10-30 parts of strontium hydrogen phosphate, 10-25 parts of magnesium oxide, 10-30 parts of aluminum oxide, and 3-18 parts of germanium oxide. , 5-15 parts of europium oxide, 5-18 parts of cerium oxide, 15-20 parts of terbium oxide, the sum of each component is 100%, and also includes co-solvent aluminum fluoride, one part of special gas, and the amount of aluminum fluoride added is 3-20% of the total weight of the base material, the specialty gas contains 7% hydrogen, 1% helium and 92% nitrogen. The beneficial effects of the invention are: the light source made of the rare earth composite phosphor specially used for the ZW-2 three-band plant growth lamp has three-band spectra, which not only has a suitable visible spectrum with high radiation energy to promote plant growth and development, but also inhibits excessive growth and promotes flowering. The ultraviolet light formed by cyanins and various pigments has absolute advantages in supplementing light for plants.
2) Prepare an injectable bone cement containing strontium. Including solid phase: polymethyl methacrylate, calcium sulfate hemihydrate, tetracalcium phosphate, strontium hydrogen phosphate, barium sulfate and benzoyl peroxide; liquid phase: methyl methacrylate monomer, N, N dimethyl p-Toluidine and hydroquinone. After the solid phase and liquid phase are mixed separately, the solid and liquid phases are mixed at a mass ratio of 2:1, stir evenly using a bone cement mixing system, and inject the bone cement using an injection system. In the strontium-containing injectable bone cement, calcium sulfate hemihydrate, tetracalcium phosphate and strontium hydrogen phosphate are evenly distributed. After implantation in the body, calcium and strontium ions are gradually degraded and released in the body, forming a honeycomb structure and guiding cells to grow in, forming Tightly combined to prevent loosening; the compressive strength of the prepared strontium-containing injectable bone cement is above 50MPa. The invention can be used for fixing fractures and filling bone defects caused by osteoporosis.
Preparation[4-5]
Method 1: A method for preparing strontium hydrogen phosphate, including the following steps: adding a hydrogen phosphate-dihydrogen phosphate buffer solution with a pH of 6 to 9 in the reaction tank, and then oxidizing hydrogen at an equal molar concentration The strontium solution and the phosphoric acid solution were added into the reaction tank at equal flow rates; the volume ratio of the buffer solution, the strontium hydroxide solution, and the phosphoric acid solution was 1:1:1. The specific method is: add 50L of ammonium hydrogen phosphate-ammonium dihydrogen phosphate buffer solution with a pH of 6 to the reaction tank, in which the concentration of ammonium hydrogen phosphate-ammonium dihydrogen phosphate buffer solution is 0.1 mol/L; add 1.5 mol/L of the ammonium hydrogen phosphate-ammonium dihydrogen phosphate buffer solution. Strontium hydroxide solution and 1.5 mol/L phosphoric acid solution are added into the reaction tank at an equal flow rate. The added volumes of the strontium hydroxide solution and phosphoric acid solution are both 50L; strontium hydroxide and phosphoric acid react at room temperature for 1 hour to generate Strontium hydrogen phosphate. After the reaction, the reaction solution is centrifuged, and the precipitation is dried to obtain the strontium hydrogen phosphate product. After the supernatant is concentrated and recovered by membrane, it is prepared into an ammonium hydrogen phosphate-ammonium dihydrogen phosphate buffer solution with a pH of 6, and is reused. . After testing, the content of strontium hydrogen phosphate in the strontium hydrogen phosphate product produced in this example is 99%, the product strontium to phosphorus ratio is 1.01, and the product particle size D50 is 40 μm; ammonium hydrogen phosphate-dihydrogen phosphate is used after being concentrated through membranes and reused. Ammonium buffer solution, after recycling for 5 batches, the prepared strontium hydrogen phosphate productThere is no change in quality.
Method 2: A fluorescent grade strontium hydrogen phosphate
1. Preparation of strontium chloride hexahydrate
(1) Chemical material: Crush the strontium ore to 120 mesh and add it to pure water to form a slurry. Then add 20% hydrochloric acid to form a chemical material liquid. Adjust the pH value of the chemical material liquid to 3. The concentration is 35 degrees Baume;
(2) Impurity removal: Add 20% hydrogen peroxide with a mass fraction of 7kg/m3 to the chemical liquid obtained in step (1). After reacting for 30 minutes, add 0.1kg/m3 in an amount. Activated carbon, heat up to 80°C, finally adjust the pH value to 6, keep it warm for 50 minutes and then filter to get the filtrate;
(3) Adjust the pH value of the filtrate obtained in step (2) to 5, then concentrate it until the concentration of the filtrate is 42 degrees Baume, and finally cool and crystallize under stirring to prepare strontium chloride hexahydrate. .
2. Prepare strontium chloride solution: Add strontium chloride hexahydrate and deionized water into the chemical tank, stir to form a material liquid with a concentration of 21 degrees Baume, and then add 5kg/m3 to the solution. Add 20% mass fraction of hydrogen peroxide to the material liquid, raise the temperature to 75°C at a rate of 1.0°C/min, then add strontium hydroxide solution to adjust the pH to 8.5, then add activated carbon at an amount of 0.5kg/m3, and keep stirring for 45 minutes. After filtering, take the filtrate, adjust the pH value of the filtrate to 4, control the strontium chloride concentration in the filtrate to 335g/L, Fe concentration ≤ 0.005g/L, Ca concentration ≤ 0.05g/L, and Pb concentration ≤ 0.005g /L is enough.
3. Prepare diammonium hydrogen phosphate solution: Add diammonium hydrogen phosphate and deionized water into the chemical tank, stir until the diammonium hydrogen phosphate is completely dissolved, then add activated carbon at an amount of 0.1kg/m3, and filter Take the filtrate, adjust the pH value of the filtrate to 7.8, control the concentration of diammonium hydrogen phosphate in the filtrate to 135g/L, and the Fe concentration ≤ 0.005g/L.
4. Prepare fluorescent grade strontium hydrogen phosphate: Inject the strontium chloride solution at a flow rate of 800L/h and the diammonium hydrogen phosphate solution at a flow rate of 1000L/h into the synthesis reaction kettle at the same time. At a pH value of 4.2, the rotation speed is 110r/min, the temperature is 65℃, stop injecting the strontium chloride solution and diammonium hydrogen phosphate solution for 110min, continue stirring for 5min and then adjust the pH value to 4.0, then age for 10min and then obtain the precipitate through vacuum filtration or centrifugation. Place the precipitate in water at 80°C, stir and soak for 5 minutes, then take it out. First, wash it with water through a vacuum filter, and then centrifuge the washed precipitate. Repeat this cycle 4 times until the Cl content in the precipitate is <0.03wt%. Finally, dry at 120°C.
Main references
[1] Wet synthesis of nanometer strontium hydrogen phosphate
[2] CN201110069790.5 Preparation method of rare earth composite phosphor for three-band plant growth lamp
[3] CN201410385440.3 Strontium-containing injectable bone cement and preparation method
[4] CN201410824413.1 A kind of preparation method of strontium hydrogen phosphate
[5] CN201811427983.1 A preparation method and product of fluorescent grade strontium hydrogen phosphate
