Preparation method of ruthenium nitrosyl nitrate solution and ruthenium nitrosyl nitrate solution
By introducing nitric oxide and nitrogen dioxide into an ice-water bath to generate nitrous acid, and adding silver nitrate during reflux to remove chloride ions, the problems of low yield and high cost of nitrosyl ruthenium nitrate solution were solved, and high-purity nitrosyl ruthenium nitrate was prepared.
Patent Information
- Application Number
- CN202410909107.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-08
- Publication Date
- 2026-01-09
AI Technical Summary
Existing methods for preparing ruthenium nitrite solution have low yields, resulting in high costs, and the presence of halogens in existing precursors affects catalytic performance.
A high-purity nitrosyl ruthenium nitrate solution was prepared by passing a mixture of nitric oxide and nitrogen dioxide gas through hydrated ruthenium trichloride in an ice-water bath to generate nitrous acid, followed by heating, stirring, and reflux, and adding silver nitrate to remove chloride ions.
This improved the yield of ruthenium nitrite nitrite, reduced raw material costs, and ensured that the catalyst was free of halogen contamination and met high purity requirements.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of ruthenium-based noble metal catalysts, and particularly relates to a preparation method of a nitrosyl ruthenium nitrate solution and the nitrosyl ruthenium nitrate solution. BACKGROUND
[0002] In the catalytic industry, as a three-way catalyst for vehicle exhaust treatment, a noble metal three-way catalyst is generally composed of platinum, palladium and rhodium. However, other noble metals used in the three-way catalyst have some problems, such as toxicity, low catalytic efficiency, high price and difficult process. At present, ruthenium has been introduced into the three-way catalyst. Ruthenium has similar catalytic performance to rhodium and is cheaper than rhodium. The catalyst scheme using ruthenium to replace rhodium can effectively reduce the product cost. At present, the precursors for preparing the supported ruthenium catalyst on the market mainly include hydrated ruthenium trichloride, triruthenium dodecacarbonyl, nitrosyl ruthenium nitrate, ruthenium acetylacetonate and potassium ruthenate. The hydrated ruthenium trichloride is the most common ruthenium compound, which is stable and cheap. However, the precursor contains a large amount of chloride ions, and the residual chloride ions on the catalyst cannot be completely removed during the preparation of the catalyst, which has a certain inhibitory effect on the catalytic performance.
[0003] Compared with ruthenium trichloride, the halogen-free ruthenium precursor compound such as nitrosyl ruthenium nitrate is an ideal precursor for preparing the supported ruthenium catalyst. The nitrosyl ruthenium nitrate does not contain halogen, sulfur and phosphorus elements which are easy to poison the catalyst, and is an ideal catalytic precursor. However, the price of such compounds is relatively high, and the preparation method of the nitrosyl ruthenium nitrate has the technical problem of low yield. SUMMARY
[0004] In view of the problems in the background art, the present application aims to provide a preparation method of a nitrosyl ruthenium nitrate solution, which can promote the forward reaction of nitrosyl ruthenium chloride, ensure the formation of the intermediate nitrosyl ruthenium chloride, and effectively improve the yield of the nitrosyl ruthenium nitrate. In addition, the raw material cost is low, and the technical problems of low yield of the existing preparation method of the nitrosyl ruthenium nitrate solution and high price of the nitrosyl ruthenium nitrate are solved.
[0005] Another object of the present application is to provide the nitrosyl ruthenium nitrate solution prepared by the above preparation method of the nitrosyl ruthenium nitrate solution, which has the characteristic of high purity.
[0006] To achieve the above object, the present application adopts the following technical scheme:
[0007] A preparation method of a nitrosyl ruthenium nitrate solution, comprising the following steps:
[0008] Step A, dissolving hydrated ruthenium trichloride in a nitric acid solution, stirring under an ice water bath, and passing a mixed gas of nitrogen monoxide and nitrogen dioxide;
[0009] Step B, heating and stirring the solution obtained in Step A to reflux, and maintaining a mixed gas of nitric oxide and nitrogen dioxide flowing in the reflux to obtain a nitric acid solution of nitrosylchlororuthenate;
[0010] Step C, adding silver nitrate to the nitric acid solution of nitrosylchlororuthenate obtained in Step B to generate nitrosyl nitrate ruthenium by stirring, and adding hydrochloric acid solution dropwise until no silver chloride precipitate is generated, and removing excess silver ions;
[0011] Step D, filtering the solution obtained in Step C to remove the silver chloride precipitate generated in Step C, rinsing the filter residue with a nitric acid solution, and combining the filtrate and the rinsing solution to obtain a nitrosyl nitrate ruthenium solution.
[0012] Further, in Step A, the volume ratio of the nitric oxide to the nitrogen dioxide flowing in is 1:1, and the flow rate of the mixed gas is 0.1 L / min to 0.2 L / min, and the flow time is 15 min to 45 min.
[0013] Further, in Step B, the volume ratio of the nitric oxide to the nitrogen dioxide flowing in is 1:1, and the flow rate of the mixed gas is 0.4 L / min to 0.5 L / min.
[0014] Further, in Step B, the reflux temperature of heating and stirring the solution obtained in Step A to reflux is 75°C to 85°C, and after heating for 10 min to 20 min, the solution is observed to change from dark red to light red, and after the color no longer changes, the reflux temperature and the flow rate are maintained, and the reaction is continued for 30 min to 240 min.
[0015] Further, in Step A, when dissolving the hydrated ruthenium trichloride in the nitric acid solution, 1 gram of the hydrated ruthenium trichloride is dissolved in 10 mL of the nitric acid solution, and the stirring temperature under an ice water bath is 0°C to 3°C.
[0016] Further, in Step C, the amount of the silver nitrate added is that the molar ratio of the hydrated ruthenium trichloride to the silver nitrate is 1:3.05.
[0017] Further, after combining the filtrate and the rinsing solution to obtain the nitrosyl nitrate ruthenium solution, Step E is further included, which comprises the following steps:
[0018] adding hydrazine hydrate to the silver chloride precipitate after the rinsing is completed, stirring to react until the white silver chloride changes to gray metallic silver, filtering and washing the metallic silver to dryness to obtain recovered metallic silver;
[0019] dissolving the recovered metallic silver in nitric acid to prepare silver nitrate.
[0020] A nitrosyl nitric ruthenium solution, a preparation method of the nitrosyl nitric ruthenium solution.
[0021] Compared with the prior art, the embodiments of the present application have the following beneficial effects:
[0022] 1. By using the ice bath method to absorb the NO and NO2 mixed gas to directly generate nitrous acid, the nitrosyl is directly introduced, and the nitrous acid or sodium nitrite is not needed to be prepared separately.
[0023] 2. By passing the mixed gas of nitrogen monoxide (NO) and nitrogen dioxide (NO2) into the nitric acid solution of ruthenium under the ice bath in step A, the nitrous acid is generated by the reaction with water in the solution, a large amount of nitrous acid provides excess nitrosyl to make the reaction occur in the positive direction, and the generation of the intermediate nitrosyl ruthenium trichloride is ensured.
[0024] 3. The mixed gas of NO and NO2 is continuously passed in the reflux process in step B, the concentration of nitrous acid in the solution is maintained, the reverse reaction of nitrosyl ruthenium trichloride is inhibited, and the nitrosylation reaction is ensured to be complete. After the nitrosylation reaction is complete, silver nitrate is added to precipitate chlorine ions to generate the nitrosyl nitric ruthenium solution. In the whole reaction process, the key point is the generation of the intermediate nitrosyl ruthenium chloride. Since the nitrosyl reaction is a reversible reaction, the excess nitrosyl is obtained by introducing excess nitrous acid, and then the occurrence of the positive reaction is promoted, the formation of nitrosyl ruthenium chloride is ensured, and the yield of nitrosyl nitric ruthenium is effectively improved.
[0025] 4. By using the hydrated ruthenium trichloride as the raw material, compared with the use of ruthenium powder, the steps such as distillation of ruthenium are avoided, the whole reaction system occurs in one container, and the yield reduction caused by the loss of intermediate transfer is avoided. BRIEF DESCRIPTION OF DRAWINGS
[0026] Figure 1 It is a reaction principle schematic diagram of the preparation method of the nitrosyl nitric ruthenium solution of one embodiment of the present application. DETAILED DESCRIPTION
[0027] A preparation method of a nitrosyl nitric ruthenium solution, comprising the following steps:
[0028] Step A, dissolving the hydrated ruthenium trichloride in the nitric acid solution, stirring under the ice water bath, and passing the mixed gas of nitrogen monoxide and nitrogen dioxide;
[0029] Step B, heating and stirring the solution obtained in step A to reflux, and continuously passing the mixed gas of nitrogen monoxide and nitrogen dioxide in the reflux to obtain the nitric acid solution of nitrosyl ruthenium trichloride;
[0030] Step C, silver nitrate is added to the nitric acid solution of nitrosylchlororuthenium obtained in step B to generate nitrosyl nitrate ruthenium, and hydrochloric acid solution is added dropwise until no silver chloride precipitate is generated, and the excess silver ions are removed;
[0031] Step D, the solution obtained in step C is filtered to remove the silver chloride precipitate generated in step C, the filter residue is washed with nitric acid solution, and the filtrate and the washing solution are combined to obtain a nitrosyl nitrate ruthenium solution.
[0032] The key to the synthesis of nitrosyl nitrate ruthenium is the introduction of a nitrosyl group, and the introduction of nitrosyl is related to the yield of nitrosyl nitrate ruthenium and the stability of the finished product. In the preparation method of the present application, the hydrated ruthenium trichloride is dissolved in a nitric acid solution, a mixed gas of nitric oxide and nitrogen dioxide is introduced into the solution under an ice water bath to generate nitrous acid, and then nitrosylation is carried out through step B heating, stirring and refluxing to promote the generation of the intermediate nitrosyl chlororuthenium. After the reaction is complete, silver nitrate is added to remove chloride ions, and then a high-purity nitrosyl nitrate ruthenium solution is obtained, and the yield can reach 99.2%.
[0033] By introducing a mixed gas of nitric oxide (NO) and nitrogen dioxide (NO2) into the nitric acid solution of ruthenium under an ice bath in step A, nitrous acid is generated by reacting with water in the solution. A large amount of nitrosyl is provided by the excess nitrous acid to make the reaction occur in the forward direction, ensuring the generation of the intermediate nitrosyl trichloride ruthenium. During the refluxing process in step B, the mixed gas of NO and NO2 is continuously introduced to maintain the concentration of nitrous acid in the solution and inhibit the reverse reaction of nitrosyl trichloride ruthenium, ensuring the complete nitrosylation reaction. After the nitrosylation reaction is complete, silver nitrate is added to precipitate chloride ions to generate a nitrosyl nitrate ruthenium solution. During the entire reaction process, the key point is the generation of the intermediate nitrosyl chlororuthenium. Since the nitrosyl reaction is a reversible reaction, by introducing excess nitrous acid to obtain excess nitrosyl, the occurrence of the forward reaction is promoted, the formation of nitrosyl chlororuthenium is ensured, and the yield of nitrosyl nitrate ruthenium is effectively improved.
[0034] The present application uses an ice bath method to absorb the mixed gas of NO and NO2 to directly generate nitrous acid, thereby directly introducing nitrosyl, without the need for separately preparing nitrous acid or adding sodium nitrite. In addition, by introducing excess nitrosyl, the yield of the intermediate nitrosyl chlororuthenium is promoted, and the yield of nitrosyl nitrate ruthenium is improved. Compared with using ruthenium powder, the hydrated ruthenium trichloride is used as a raw material, avoiding steps such as distillation of ruthenium. The entire reaction system occurs in one container, avoiding the loss of yield caused by intermediate transfer. In the reaction system, no other metal ions are introduced except silver ions, and the concentration of trace silver ions can be maintained through reaction control, ensuring that there are no halogen elements that can poison the catalyst in the nitrosyl nitrate ruthenium.
[0035] Further, the inventors found that, compared with the method of generating HNO2 solution in advance, dissolving RuCl3 in dilute nitric acid solution, and adding the HNO2 solution while heating and refluxing, the above method needs to prepare nitrous acid in advance, and the concentration and acidity of the nitrous acid solution cannot be guaranteed. After adding the nitrous acid solution, the volume of the solution increases, and the acidity decreases. If the acidity of the high-concentration nitrosyl nitric ruthenium cannot be maintained, the nitrosyl nitric ruthenium will hydrolyze, resulting in a reduced yield. Adding too much nitrous acid solution also increases unnecessary working hours for subsequent concentration. The preparation method of the present application directly absorbs NO and NO2 gas in a nitric acid solution of ruthenium to directly prepare nitrous acid, which can maintain the volume of the solution unchanged and the acidity sufficient. By continuously passing the mixed gas, the concentration of nitrosyl in the reaction system can be guaranteed, and the reaction can be ensured to proceed.
[0036] The price of nitrosyl nitric ruthenium on the market is 135 yuan per gram. The preparation method is simple to operate, and the raw materials are easy to obtain. Through experimental verification, the cost of nitrosyl nitric ruthenium per gram of ruthenium is 107.44 yuan, which is about 27.5 yuan per gram lower than the market price.
[0037] The preparation method of the nitrosyl nitric ruthenium solution can promote the forward reaction of nitrosyl chlororuthenate, ensure the formation of the intermediate nitrosyl chlororuthenate, and effectively improve the yield of nitrosyl nitric ruthenium. The raw material cost is low, and the technical problems of low yield and high price of the existing nitrosyl nitric ruthenium solution preparation method are solved.
[0038] Further, in step A, the volume ratio of the nitric oxide to the nitrogen dioxide is 1:1, the ventilation rate of the mixed gas is 0.1 L / min to 0.2 L / min, and the ventilation time is 15 min to 45 min.
[0039] By optimizing the ventilation rate and ventilation time of the mixed gas, if the ventilation rate of the mixed gas is too high, the mixed gas cannot be completely absorbed, and the gas will escape. In addition, by optimizing the volume ratio of the nitric oxide to the nitrogen dioxide to 1:1, and the ventilation rate of the mixed gas to 0.1 L / min to 0.2 L / min and the ventilation time, the mixed gas of nitric oxide (NO) and nitrogen dioxide (NO2) is ensured to react with water in the solution to generate nitrous acid, a large amount of nitrous acid is generated to provide excess nitrosyl, the reaction proceeds in the forward direction, and the generation of the intermediate nitrosyl chlororuthenate is ensured.
[0040] Further, in step B, the volume ratio of the nitrogen monoxide to the nitrogen dioxide is 1:1, and the ventilation rate of the mixed gas is 0.4L / min-0.5L / min.
[0041] By preferably ventilating the nitrogen monoxide and the nitrogen dioxide at a volume ratio of 1:1 and the ventilation rate of the mixed gas being 0.4L / min-0.5L / min, the amount of the continuously ventilated mixed gas of NO and NO2 is ensured, thereby maintaining the concentration of nitrous acid in the solution, inhibiting the reverse reaction of nitrosyl ruthenium trichloride, and ensuring the complete nitrosylation reaction.
[0042] Preferably, in step B, the reflux temperature of the solution obtained in step A is heated and stirred under reflux, and the reflux temperature is 75℃-85℃. After heating for 10min-20min, the solution is observed to change from dark red to light red. After the color no longer changes, the reflux temperature and the ventilation rate are maintained, and the reaction is continuously carried out for 30min-240min.
[0043] In step B, the reflux temperature of the solution obtained in step A is preferably heated and stirred under reflux, and the reflux temperature is 75℃-85℃. If the reflux temperature is too low, the reaction rate will be low, and the required reaction time will be long.
[0044] Preferably, in step A, when the hydrated ruthenium trichloride is dissolved in the nitric acid solution, 1 gram of the hydrated ruthenium trichloride is dissolved in 10mL of the nitric acid solution, and the stirring temperature under the ice water bath is 0℃-3℃.
[0045] By dissolving 1 gram of the hydrated ruthenium trichloride in 10mL of the nitric acid solution, the dissolution effect of the hydrated ruthenium trichloride is ensured, thereby ensuring the formation of the nitrosyl ruthenium chloride. The mass fraction of the nitric acid solution in step A is 20%.
[0046] Preferably, in step C, the amount of the silver nitrate added is that the molar ratio of the hydrated ruthenium trichloride to the silver nitrate is 1:3.05.
[0047] Further, after the nitrosyl nitric ruthenium solution is obtained by combining the filtrate and the washing liquid, step E is further included, which comprises the following steps:
[0048] Hydrazine hydrate is added to the washed silver chloride precipitate, and the reaction is stirred until the white silver chloride is changed into gray metallic silver. The metallic silver is filtered, washed, and dried to obtain the recovered metallic silver.
[0049] The recovered metallic silver is dissolved in nitric acid to prepare silver nitrate.
[0050] The silver chloride precipitate generated in the step C is recovered by washing the silver chloride precipitate, i.e. the filter residue, and adding hydrazine hydrate to the washed silver chloride precipitate, so that the silver is reduced from the silver chloride and recovered. The recovered silver is dissolved in nitric acid, and the prepared silver nitrate solution can be used next time. In addition, the recovery rate can be detected after the recovery of the silver.
[0051] Specifically, in the step E, the white silver chloride is converted into gray metallic silver by adding excess hydrazine hydrate, and the amount of the hydrazine hydrate required for the conversion of the white silver chloride into the gray metallic silver is that the molar ratio of the hydrazine hydrate to the silver is 2.5:1, i.e. 2.5 mol of the hydrazine hydrate: 1 mol of the silver.
[0052] A ruthenium nitrosyl nitrate solution is prepared by the preparation method of the ruthenium nitrosyl nitrate solution.
[0053] The ruthenium nitrosyl nitrate solution prepared by the preparation method of the ruthenium nitrosyl nitrate solution has the characteristic of high purity.
[0054] In order to facilitate the understanding of the present application, the present application will be described more fully below. The present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.
[0055] Unless otherwise specified in the examples, the techniques or conditions are performed according to the techniques or conditions described in the literature in the art or according to the product instructions. Unless otherwise specified, the reagents or instruments used are conventional products that can be obtained commercially.
[0056] Example 1
[0057] A preparation method of a ruthenium nitrosyl nitrate solution, comprising the following steps:
[0058] In step A, 5 g of hydrous ruthenium trichloride (ruthenium content: 37.01%) is dissolved in a 250 mL flask containing 50 mL of a nitric acid solution (mass fraction: 20%) under stirring in an ice water bath, the temperature of the stirring in the ice water bath is 0-3°C, a mixed gas of nitric oxide and nitrogen dioxide is introduced, the volume ratio of the introduced nitric oxide to nitrogen dioxide is 1:1, the gas flow rate of the mixed gas is 0.1 L / min, and the gas flow time is 15 min.
[0059] Step B, the solution obtained in step A was transferred into a heating jacket, heated and stirred under reflux, the reflux temperature was 75℃, the mixed gas of nitric oxide and nitrogen dioxide was kept flowing in the reflux, the volume ratio of nitric oxide to nitrogen dioxide was 1:1, the flow rate of the mixed gas was 0.4L / min, the solution was observed to change from dark red to light red after 10min of heating, after the color no longer changed, the reflux temperature and the flow rate were kept, the reaction was continued for 30min, after the reaction was completed, the heating was stopped, the reaction solution was cooled to room temperature in a water bath, and a nitric acid solution of nitrosyl chlororuthenate was obtained;
[0060] Step C, 9.45g of silver nitrate was dissolved in 20mL of deionized water, the silver nitrate was added to the nitric acid solution of nitrosyl chlororuthenate obtained in step B, and nitrosyl nitrate ruthenium was generated by stirring, silver chloride precipitate appeared, 1mol / L hydrochloric acid solution was added dropwise until no silver chloride precipitate was generated, stirring was continued for 15min to ensure complete precipitation and remove excess silver ions;
[0061] Step D, the solution obtained in step C was filtered to remove the silver chloride precipitate generated in step C, the filter residue was washed with a 20wt% nitric acid solution, and the filtrate and the washing liquid were combined to obtain a nitrosyl nitrate ruthenium solution.
[0062] The solution obtained in Example 1 was diluted to 100mL, and was measured using an inductively coupled plasma emission spectrometer (ICP), the mass fraction of impurity elements was ≤0.05%, which met the requirements of the standard YS / T 755-2011 nitrosyl nitrate ruthenium, the content of ruthenium was 18.357g / L, and the yield of nitrosyl nitrate ruthenium was 99.2%.
[0063] Example 2
[0064] A method for preparing a nitrosyl nitrate ruthenium solution, comprising the following steps:
[0065] Step A, 100g of hydrated ruthenium trichloride (ruthenium content of 37.01%) was dissolved in a 3L flask containing 1L of a nitric acid solution (20wt%), stirring was performed under an ice water bath, the temperature of stirring under the ice water bath was 0℃-3℃, a mixed gas of nitric oxide and nitrogen dioxide was flowed in, the volume ratio of nitric oxide to nitrogen dioxide was 1:1, the flow rate of the mixed gas was 0.1L / min, and the flow time was 30min;
[0066] Step B, the solution obtained in step A was transferred into a heating jacket, heated and stirred under reflux, the reflux temperature was 80℃, the mixed gas of nitric oxide and nitrogen dioxide was kept flowing in the reflux, the volume ratio of nitric oxide to nitrogen dioxide was 1:1, the flow rate of the mixed gas was 0.5L / min, the solution was observed to change from dark red to light red after 20min of heating, after the color no longer changed, the reflux temperature and the flow rate were kept, the reaction was continued for 2h, after the reaction was completed, the heating was stopped, the reaction solution was cooled to room temperature in a water bath, and a nitric acid solution of nitrosyl chlororuthenate was obtained;
[0067] Step C, 189g of silver nitrate was dissolved in 200mL of deionized water, the nitric acid solution of nitrosyl chlororuthenate obtained in step B was added with silver nitrate, and nitrosyl nitrate ruthenium was generated by stirring reaction, silver chloride precipitate appeared, 1mol / L hydrochloric acid solution was added dropwise until no silver chloride precipitate was generated, stirring was continued for 30min to ensure complete precipitation and remove excess silver ions;
[0068] Step D, the solution obtained in step C was filtered, and the silver chloride precipitate generated in step C was filtered, the filter residue was washed with a 20wt% nitric acid solution, and the filtrate and the washing liquid were combined to obtain a nitrosyl nitrate ruthenium solution.
[0069] The solution obtained in Example 2 was heated and concentrated to 1L, and was measured using an inductively coupled plasma emission spectrometer (ICP), the mass fraction of impurity elements was ≤0.05%, which met the requirements of the standard YS / T 755-2011 nitrosyl nitrate ruthenium, the content of ruthenium was 35.715g / L, and the yield of nitrosyl nitrate ruthenium was 96.5%.
[0070] Example 3
[0071] A method for preparing a nitrosyl nitrate ruthenium solution, comprising the following steps:
[0072] Step A, 100g of hydrated ruthenium trichloride (ruthenium content was 37.01%) was dissolved in a 3L flask containing 1L of a nitric acid solution (20wt%), stirring was carried out under an ice water bath, the temperature of stirring under the ice water bath was 0℃-3℃, a mixed gas of nitric oxide and nitrogen dioxide was flowed in, the volume ratio of nitric oxide to nitrogen dioxide was 1:1, the flow rate of the mixed gas was 0.2L / min, and the flow time was 45min;
[0073] Step B, the solution obtained in step A was transferred into a heating jacket, heated and stirred under reflux, the reflux temperature was 85℃, the mixed gas of nitric oxide and nitrogen dioxide was kept flowing in the reflux, the volume ratio of nitric oxide to nitrogen dioxide was 1:1, the flow rate of the mixed gas was 0.5L / min, the solution was observed to change from dark red to light red after 20min of heating, after the color no longer changed, the reflux temperature and the flow rate were kept, the reaction was continued for 4h, after the reaction was completed, the heating was stopped, the reaction solution was cooled to room temperature in a water bath, and a nitric acid solution of nitrosyl chlororuthenate was obtained;
[0074] Step C, 189g of silver nitrate was dissolved in 200mL of deionized water, the nitric acid solution of nitrosyl chlororuthenate obtained in step B was added with silver nitrate, and nitrosyl nitrate ruthenium was generated by stirring reaction, silver chloride precipitate appeared, 1mol / L hydrochloric acid solution was added dropwise until no silver chloride precipitate was generated, stirring was continued for 30min to ensure complete precipitation and remove excess silver ions;
[0075] Step D, the solution obtained in step C was filtered to filter the silver chloride precipitate generated in step C, the filter residue was washed with a 20wt% nitric acid solution, and the filtrate and the washing liquid were combined to obtain a nitrosyl nitrate ruthenium solution.
[0076] The solution obtained in Example 3 was heated and concentrated to 1L, and was measured using an inductively coupled plasma emission spectrometer (ICP), the mass fraction of impurity elements was ≤0.05%, which met the requirements of the standard YS / T 755-2011 nitrosyl nitrate ruthenium, the content of ruthenium was 36.418g / L, and the yield of nitrosyl nitrate ruthenium was 98.4%.
[0077] Example 4
[0078] A method for preparing a nitrosyl nitrate ruthenium solution, comprising the following steps:
[0079] Step A, 5g of hydrated ruthenium trichloride (ruthenium content was 37.01%) was dissolved in a 250mL flask containing 50mL of a nitric acid solution (20wt%), stirring was carried out under an ice water bath, the temperature of stirring under the ice water bath was 0℃-3℃, a mixed gas of nitric oxide and nitrogen dioxide was flowed in, the volume ratio of nitric oxide to nitrogen dioxide was 1:1, the flow rate of the mixed gas was 0.1L / min, and the flow time was 15min;
[0080] Step B, the solution obtained in step A is transferred into a heating jacket, heated and stirred under reflux, the reflux temperature is 75℃, the mixed gas of nitric oxide and nitrogen dioxide is kept flowing in the reflux, the volume ratio of nitric oxide to nitrogen dioxide is 1:1, the flow rate of the mixed gas is 0.4L / min, the solution is observed to change from dark red to light red after 10min of heating, after the color no longer changes, the reflux temperature and the flow rate are kept, the reaction is continued for 30min, after the reaction is completed, the heating is stopped, the reaction solution is cooled to room temperature in a water bath, and a nitric acid solution of nitrosyl chlororuthenate is obtained;
[0081] Step C, 9.45g of silver nitrate is dissolved in 20mL of deionized water, the silver nitrate is added to the nitric acid solution of nitrosyl chlororuthenate obtained in step B, and nitrosyl nitrate ruthenium is generated by stirring, silver chloride precipitate is generated, 1mol / L hydrochloric acid solution is added dropwise until no silver chloride precipitate is generated, stirring is continued for 15min to ensure that the precipitate is completely removed and the excess silver ions are removed;
[0082] Step D, the solution obtained in step C is filtered, the silver chloride precipitate generated in step C is filtered, the filter residue is washed with a 20% mass fraction nitric acid solution, and the filtrate and the washing liquid are combined to obtain a nitrosyl nitrate ruthenium solution;
[0083] Step E, hydrazine hydrate is added to the washed silver chloride precipitate, and the reaction is stirred until the white silver chloride is changed into gray metallic silver, the metallic silver is filtered and washed to obtain recovered metallic silver;
[0084] The recovered metallic silver is dissolved in nitric acid to prepare silver nitrate.
[0085] The above embodiments only express several embodiments of the present application, the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of variations and improvements can be made, which are within the scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.
Claims
1. A method for preparing a ruthenium nitrosyl nitrate solution, characterized by, The method comprises the following steps: Step A, dissolving hydrated ruthenium trichloride in nitric acid solution, stirring under ice water bath, and passing mixed gas of nitric oxide and nitrogen dioxide; Step B, heating and stirring the solution obtained in step A to reflux, and maintaining the refluxing by passing mixed gas of nitric oxide and nitrogen dioxide, to obtain nitrosyl chlororuthenate nitrate solution; Step C, adding silver nitrate to the nitrosyl chlororuthenate nitrate solution obtained in step B, and stirring to generate nitrosyl nitrate ruthenium, and adding hydrochloric acid solution until no silver chloride precipitate is generated, and removing excess silver ions; Step D, filtering the solution obtained in step C to remove silver chloride precipitate generated in step C, rinsing the filter residue with nitric acid solution, and combining the filtrate and the rinsing solution to obtain nitrosyl nitrate ruthenium solution.
2. The method for preparing ruthenium nitrite solution according to claim 1, characterized in that, In step A, the volume ratio of the nitric oxide to the nitrogen dioxide is 1:1, the passing rate of the mixed gas is 0.1L / min-0.2L / min, and the passing time is 15min-45min.
3. The method for preparing ruthenium nitrite solution according to claim 1, characterized in that, In step B, the volume ratio of the nitric oxide to the nitrogen dioxide is 1:1, and the passing rate of the mixed gas is 0.4L / min-0.5L / min.
4. The method for preparing ruthenium nitrite solution according to claim 3, characterized in that, In step B, the refluxing temperature of heating and stirring the solution obtained in step A to reflux is 75℃-85℃, and the solution changes from dark red to light red after 10min-20min of heating, and the refluxing temperature and the passing rate are maintained after the color no longer changes, and the reaction is continued for 30min-240min.
5. The method for preparing ruthenium nitrite solution according to claim 1, characterized in that, In step A, when dissolving hydrated ruthenium trichloride in nitric acid solution, 1g of the hydrated ruthenium trichloride is dissolved in 10mL of nitric acid solution, and the stirring temperature under ice water bath is 0℃-3℃.
6. The method for preparing ruthenium nitrite solution according to claim 1, characterized in that, In step C, the adding amount of the silver nitrate is that the molar ratio of the hydrated ruthenium trichloride to the silver nitrate is 1:3.
05.
7. The method for preparing ruthenium nitrite solution according to claim 1, characterized in that, After combining the filtrate and the rinsing solution to obtain nitrosyl nitrate ruthenium solution, step E is further included, which comprises the following steps: adding hydrazine hydrate to the rinsed silver chloride precipitate, stirring to react until the white silver chloride changes into gray metallic silver, filtering and washing the metallic silver, and drying to obtain recovered metallic silver; dissolving the recovered metallic silver in nitric acid to prepare silver nitrate.
8. A solution of ruthenium nitrosyl nitrate, characterized in that, The method is prepared by using the method for preparing nitrosyl nitrate ruthenium solution in any one of claims 1-7.