Method for preparing rhenium oxide diacetylacetonate
By using a method to prepare rhenium diacetylacetone, the problems of high-temperature reaction and corrosive gases in chemical vapor deposition were solved, achieving low-temperature preparation and improved safety, while expanding matrix selectivity.
Patent Information
- Application Number
- CN202511061695.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-31
- Publication Date
- 2025-11-07
AI Technical Summary
Existing chemical vapor deposition methods for preparing rhenium coatings involve high reaction temperatures and the generation of corrosive gases, which limits the selectivity of the substrate.
Cesium hexachlororhenate was prepared by reacting cesium chloride and rhenium powder, and then reacted with acetylacetone to prepare rhenium diacetylacetone oxide. The reaction temperature was reduced and the generation of corrosive gases was avoided by steps such as rotary evaporation sublimation and vacuum drying.
The low-temperature preparation of rhenium diacetylacetone was achieved, providing a wider range of matrix selectivity, avoiding equipment corrosion, and improving the safety and efficiency of the preparation process.
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to a method for preparing diacetylacetone oxorhenium, and belongs to the technical field of organic compounds of rhenium. BACKGROUND
[0002] Rhenium is a rare high-melting-point metal, has many excellent performances, such as high melting point, strong plasticity, strong anti-creep performance, is suitable for working environments of ultrahigh temperature and strong thermal shock, and therefore, rhenium and alloy pieces thereof are mainly used in aerospace components, oxidation-resistant coatings, various solid propellant thermal sensitive components and the like.
[0003] Rhenium has irreplaceable effects on the application of high-temperature alloys of aero-engines in the field of aviation due to its excellent characteristics, belongs to a strategic new material. However, rhenium is difficult to process, and chemical vapor deposition has advantages for difficult-to-process metals. At present, chemical vapor deposition of rhenium is mainly realized by reducing rhenium chloride by hydrogen, but the reaction temperature of this method is high, and the chlorine gas generated by reduction is a toxic gas and is extremely easy to corrode equipment and metal substrates, greatly limiting the selection of coating substrates. The diacetylacetone oxorhenium prepared by the application is an organic metal compound of rhenium, and has a low thermal decomposition temperature. As a precursor for chemical vapor deposition of rhenium, the diacetylacetone oxorhenium has the advantages of low reaction temperature and no corrosive gas, and can provide diversity for the selection of substrates, effectively solving the problem. SUMMARY
[0004] The application aims to provide a method for preparing diacetylacetone oxorhenium.
[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the application is as follows:
[0006] First, cesium chloride and rhenium powder are used to prepare intermediate product cesium hexachlororhodate, then potassium hexachlororhodate and acetylacetone are reacted, and diacetylacetone oxorhenium is prepared by rotary evaporation sublimation.
[0007] In the above method, the intermediate product cesium hexachlororhodate is first prepared. The cesium chloride and the rhenium powder with a mass ratio of 2:1 are ground into powder and uniformly mixed, and then placed in a 100 DEG C vacuum drying oven for drying for 24 hours.
[0008] Further, the dried powder mixture is sent to a tube furnace, slowly heated to 500 DEG C for one hour, and chlorinated in a 1L / min chlorine environment. The reaction product after the first chlorination is taken out, ground into powder, placed in a 100 DEG C vacuum drying oven for baking for 4 hours, and then loaded into the furnace for the second chlorination.
[0009] The reaction product after the second chlorination is taken out and weighed, and finally the cesium hexachlororhodate with a yield of more than 99% is obtained.
[0010] Preferably, the obtained product is dissolved in 8% dilute hydrochloric acid solvent, heated to 95°C, filtered while hot to obtain a green solution, the filtrate is concentrated on a rotary vacuum evaporator, and the rotary evaporation is stopped when a small amount of crystals precipitate, and the crystals are allowed to precipitate. The precipitated crystals are vacuum filtered to obtain a light yellow-green solid powder, which is naturally air-dried in a blast box for 24 hours, and then baked in a 100°C vacuum drying oven for 4 hours to obtain pure cesium hexachlororhodate solid powder. It can be understood that this step is to further purify cesium hexachlororhodate to obtain high-purity cesium hexachlororhodate for the next reaction.
[0011] Further, 1 kg of cesium hexachlororhodate is weighed and dissolved in 2 L of pure water (with magnetic stirring in a beaker), and then transferred to a three-necked flask. At this time, there are still some solid in the solution that has not dissolved, and 4 L of acetylacetone is added. A magnetic rotor is added to a three-necked funnel, which is placed in a constant-temperature magnetic water bath, and slowly heated to 85°C for water bath heating and reflux reaction. The magnetic stirring is turned on and stirred quickly.
[0012] Preferably, when the solid in the system slowly disappears and the solution quickly turns bright red, the pH is adjusted with a weak alkaline solution to keep the reaction system in a neutral environment. The pH value is detected until the pH of the reaction system is neutral and no longer changes;
[0013] Preferably, the heating and reflux reaction is continued at 75-85°C for 12-24 hours until the lower precipitate is completely dissolved;
[0014] The reaction solution is filtered, and the filtrate is transferred to a rotary evaporator and rotary evaporated at 85°C and 80 r / min until the filtrate is completely rotary evaporated to obtain a deep purple-red solid;
[0015] Preferably, the deep purple-red solid is transferred to a sublimator, the oil bath and vacuum pump are turned on, the oil bath temperature is 140°C, the sublimation product is collected every 2 hours until the product appears gray, and the sublimation product is completely dissolved in dehydrated anhydrous ethanol. The filtrate is filtered and rotary evaporated at 85°C and 80 r / min in a rotary evaporator to obtain diacetylacetone rhenium with a purity of 99% as a purple-red solid. DETAILED DESCRIPTION
[0016] The technical solutions of the present application will be further described below in combination with specific embodiments.
[0017] Example 1
[0018] Mixing the cesium chloride and rhenium powder with a mass ratio of 2:1 into a uniform powder, and drying in a vacuum oven at 100°C for 24 hours; after drying, the powder mixture is placed in a tube furnace and slowly heated to 500°C for 1 hour, and chlorinated in a chlorine gas environment of 1 L / min. The reaction product after the first chlorination is removed, ground into powder, and placed in a 100°C vacuum oven for 4 hours, and then placed in the furnace for the second chlorination.
[0019] The reaction product after the second chlorination is removed and weighed, and finally the yield of cesium hexachlororhenate is more than 99%. The obtained product is dissolved in 8% dilute hydrochloric acid solvent, heated to 95°C, and filtered while hot to obtain a green solution. The filtrate is concentrated on a rotary vacuum evaporator, and when a small amount of crystals precipitate, the rotary evaporation is stopped, and the crystals are allowed to precipitate. The precipitated crystals are vacuum filtered to obtain a light yellow-green solid powder, which is naturally air-dried in a blast oven for 24 hours, and then placed in a 100°C vacuum oven for 4 hours to obtain pure cesium hexachlororhenate solid powder.
[0020] Take 1 kg of cesium hexachlororhenate and add 2 L of pure water to dissolve it (with magnetic stirring in a beaker), then transfer it to a three-necked flask. At this time, there are still some solid in the solution that has not dissolved, add 4 L of acetylacetone. Add a magnetic rotor to the three-necked funnel and place it in a constant temperature magnetic water bath, slowly and stably heat to 85°C for water bath heating and reflux reaction, and open the magnetic stirring to stir quickly.
[0021] When the solid in the system slowly disappears and the solution quickly turns bright red, the pH of the reaction system is neutral and no longer changes; continue heating and refluxing at 75°C for 12 hours until the lower precipitate is completely dissolved; filter the reaction solution, and transfer the filtrate to a rotary evaporator at 85°C, at a speed of 80 r / min, until the filtrate is completely rotary dried, to obtain a deep purple red solid.
[0022] Transfer the deep purple red solid into a sublimator, turn on the oil bath and vacuum pump, the oil bath temperature is 140°C, collect the sublimation product every 2 hours, until the product appears gray, stop collecting; add anhydrous sodium sulfate to anhydrous ethanol to dry, and completely dissolve the sublimation product solid in the dehydrated anhydrous ethanol, filter the filtrate in a rotary evaporator at 85°C, 80 r / min, to finally obtain diacetylacetone rhenium with a purity of 99%, and the overall reaction conversion rate is 11.2%.
[0023] Example Two
[0024] Mixing the cesium chloride and rhenium powder with a mass ratio of 2:1 into a uniform powder, and placing it in a vacuum drying oven at 100°C for 24 hours; after drying, the powder mixture is sent to a tube furnace, slowly heated to 500°C for one hour, and chlorinated in a 1L / min chlorine environment. The reaction product after the first chlorination is removed, ground into powder, and placed in a 100°C vacuum drying oven for 4 hours, and then chlorinated again.
[0025] The reaction product after the second chlorination is removed and weighed, and the final yield of cesium hexachlororhenate is more than 99%. The resulting product is dissolved in 8% dilute hydrochloric acid solvent, heated to 95°C, and filtered while hot to obtain a green solution. The filtrate is concentrated on a rotary vacuum evaporator, and when a small amount of crystals precipitate, the rotary evaporation is stopped, and the crystals are allowed to precipitate. The precipitated crystals are vacuum filtered to obtain a light yellow-green solid powder, which is naturally air-dried in a blast oven for 24 hours, and then placed in a 100°C vacuum drying oven for 4 hours to obtain pure cesium hexachlororhenate solid powder.
[0026] Weigh 1 kg of cesium hexachlororhenate and add 2L of pure water to dissolve it (with magnetic stirring in a beaker). Transfer the solution to a three-necked flask. At this time, there are still some solid that has not dissolved in the solution. Add 4L of acetylacetone. Place a magnetic rotor in a three-necked funnel and place it in a constant-temperature magnetic water bath. Slowly and steadily heat to 85°C for water bath heating and reflux reaction. Turn on the magnetic stirrer and stir quickly.
[0027] When the solid in the system slowly disappears and the solution quickly turns bright red, adjust the pH with a weak alkaline solution to maintain a neutral environment for the reaction system. Test the pH value until the reaction system is neutral and no longer changes. Continue heating and refluxing at 85°C for 24 hours until the lower layer of precipitate is completely dissolved. Filter the reaction solution, and transfer the filtrate to a rotary evaporator at 85°C. Rotate at 80r / min until the filtrate is completely dried to obtain a deep purple-red solid.
[0028] Transfer the deep purple-red solid to a sublimator, turn on the oil bath and vacuum pump, set the oil bath temperature to 140°C, and collect the sublimation product every 2 hours until the product appears gray. Add anhydrous sodium sulfate to the anhydrous ethanol to dry it. Dissolve the sublimation product solid completely in the dehydrated anhydrous ethanol, filter the solution, and then concentrate it on a rotary evaporator at 85°C and 80r / min. Finally, obtain diacetylacetone oxorhenium with a purity of 99%, and the overall reaction conversion rate is 51.3%.
[0029] Example Three
[0030] Mixing the cesium chloride and rhenium powder with a mass ratio of 2:1 into a uniform powder, and placing it in a vacuum drying oven at 100°C for 24 hours; after drying, the powder mixture is sent to a tube furnace, slowly heated to 500°C for one hour, and chlorinated in a 1L / min chlorine environment. The reaction product after the first chlorination is removed, ground into powder, and placed in a 100°C vacuum drying oven for 4 hours, and then chlorinated again.
[0031] The reaction product after the second chlorination is removed and weighed, and the final yield of cesium hexachlororhenate is more than 99%. The resulting product is dissolved in 8% dilute hydrochloric acid solvent, heated to 95°C, and filtered while hot to obtain a green solution. The filtrate is concentrated in a rotary vacuum evaporator, and when a small amount of crystals precipitate, the rotary evaporation is stopped, and the crystals are allowed to precipitate. The precipitated crystals are vacuum filtered to obtain a light yellow-green solid powder, which is naturally air-dried in a blast oven for 24 hours, and then placed in a 100°C vacuum drying oven for 4 hours to obtain pure cesium hexachlororhenate solid powder.
[0032] Weigh 1 kg of cesium hexachlororhenate and add 2L of pure water to dissolve it (with magnetic stirring in a beaker). Transfer the solution to a three-necked flask. At this time, there are still some solid in the solution that has not dissolved. Add 4L of acetylacetone. Place a magnetic rotor in a three-necked funnel and place it in a constant-temperature magnetic water bath. Slowly heat to 85°C for water bath heating and reflux reaction. Turn on the magnetic stirrer and stir quickly.
[0033] When the solid in the system slowly disappears and the solution quickly turns bright red, adjust the pH with a weak alkaline solution to maintain a neutral environment for the reaction system. Test the pH value until the reaction system is neutral and no longer changes. Continue heating and refluxing at 85°C for 12 hours until the lower layer of the precipitate is completely dissolved. Filter the reaction solution, and transfer the filtrate to a rotary evaporator. Evaporate at 85°C with a rotation speed of 80r / min until the filtrate is completely dried to obtain a deep purple-red solid.
[0034] Transfer the deep purple-red solid into a sublimator, turn on the oil bath and vacuum pump, set the oil bath temperature to 140°C, and collect the sublimation product every 2 hours until the product appears gray. Add anhydrous sodium sulfate to the anhydrous ethanol to dry it. Dissolve the sublimation product solid completely in the dehydrated anhydrous ethanol, filter the solution, and then evaporate the filtrate in a rotary evaporator at 85°C with a rotation speed of 80r / min. Finally, obtain diacetylacetone oxorhenium with a purity of 99% and a total reaction conversion rate of 64.1%.
Claims
1. A method of preparing diacetylacetone oxorhenium characterized in that, The method comprises the following steps: firstly, mixing cesium chloride with rhenium powder, and then chlorinating to obtain cesium hexachlororhenate with a yield of more than 99%, and then purifying to obtain high-purity intermediate cesium hexachlororhenate in the form of light yellow-green solid powder; weighing the cesium hexachlororhenate, dissolving it in distilled water, then adding acetylacetone, and heating in a water bath to react, and then sublimating by rotary evaporation to obtain diacetylacetone oxorhenium.
2. A process for the preparation of a diacetylacetone oxorhenium according to claim 1, characterized in that, The cesium chloride and the rhenium powder are mixed at a mass ratio of 2:1, and then dried at 120 DEG C after mixing.
3. A process for the preparation of a diacetylacetone oxorhenium according to claim 1, characterized in that, The chlorination is performed by slowly heating to 500 DEG C for one hour, and then chlorinating once in a 1L / min chlorine environment, and then grinding the product into powder, and then baking in a 100 DEG C vacuum drying oven for 4 hours to perform secondary chlorination.
4. A process for the preparation of a diacetylacetone oxorhenium according to claim 1, characterized in that, The purification is performed by dissolving the product in 8% dilute hydrochloric acid after chlorination, heating to 95 DEG C, filtering while hot to obtain a green solution, and then rotary evaporation and drying to obtain the intermediate cesium hexachlororhenate.
5. A method of preparing a diacetylacetone oxorhenium according to claim 4, wherein, The rotary evaporation is performed by concentrating the green solution on a rotary vacuum evaporator, stopping the rotary evaporation when a small amount of crystals precipitate, and then standing to wait for the crystals to precipitate, and then vacuum filtering the precipitated crystals to obtain light yellow-green solid powder.
6. A method of preparing diacetylacetone oxorhenium according to claim 4, characterized in that, The drying is performed by natural air drying in a blast oven for 24 hours, and then baking in a 100 DEG C vacuum drying oven for 4 hours.
7. A method of preparing diacetylacetone oxorhenium according to claim 1, characterized in that, Cesium hexachlororhenate: distilled water: acetylacetone = 1 kg: 2 L: 4 L.
8. A method of preparing diacetylacetone oxorhenium according to claim 1, characterized in that, The water bath heating reaction is performed by heating to 85 DEG C, adjusting the pH to neutral and not changing, and then heating to reflux at 75-85 DEG C for 12-24 hours.
9. A method of preparing diacetylacetone oxorhenium according to claim 1, characterized in that, The rotary evaporation is performed at a temperature of 140 DEG C, and the sublimation product is collected once every 2 hours until the product appears gray, and then the collection is stopped.
10. A method of preparing a diacetylacetone oxorhenium according to claim 1, wherein, After sublimation by rotary evaporation, anhydrous sodium sulfate is added to anhydrous ethanol to dehydrate and dry, and then the sublimation product is completely dissolved in the dehydrated anhydrous ethanol, and then rotary evaporation is performed to obtain the final product.