Rapid preparation method of sodium perrhenate

Abstract

The invention discloses a rapid preparation method of sodium perrhenate, which comprises the following steps: step 1, dissolving perrhenate in deionized water to obtain a perrhenate solution, and then enabling the perrhenate solution to flow through an exchange column filled with H + type cationic resin to obtain a perrhenic acid solution; the perrhenate is ammonium perrhenate or potassium perrhenate; and 2, adding sodium borohydride into the perrhenic acid solution obtained in the step 1, stirring, and then carrying out centrifugal filtration and drying to obtain a sodium perrhenate solid. According to the preparation method, NH4 < + > or K < + > in perrhenate and H < + > in H < + > type cationic resin are subjected to an exchange reaction to obtain a perrhenic acid solution, then sodium borohydride is added to be subjected to a precipitation reaction with perrhenic acid to obtain a sodium perrhenate solid, the preparation cost of sodium perrhenate is effectively reduced, the preparation period of sodium perrhenate is effectively shortened, and the preparation method is suitable for the technical field of sodium perrhenate synthesis.

Description

Technical Field

[0001] The invention belongs to the technical field of sodium perrhenate synthesis, and in particular relates to a rapid preparation method of sodium perrhenate. Background Art

[0002] Sodium perrhenate is a special sodium salt containing Re (VII) that is easily soluble in water (its solubility is 1100 g / L at 20°C) and can be used as a precursor for rhenium nitride, ammonia synthesis and a catalyst for hydrodenitrogenation. At present, sodium perrhenate solid is mainly synthesized by evaporating and crystallizing a mixed solution of ammonium perrhenate or perrhenic acid and sodium hydroxide at high temperature. This traditional process has the disadvantages of high energy consumption, emission of irritating NH3 gas, poor crystallinity of sodium perrhenate and long time consumption due to evaporation of a large amount of water.

[0003] At present, some researchers have obtained sodium perrhenate with good crystallinity from NaReO4-H2O-C2H5OH solution by adding ethanol-induced crystallization to the traditional process, and its purity has also been improved. Although the improved process improves the purity and crystallinity of sodium perrhenate, crude sodium perrhenate must be obtained through the traditional process before ethanol-induced crystallization can be carried out at room temperature. It can be seen that the current synthesis of sodium perrhenate still relies on the traditional evaporation crystallization process, which is costly and time-consuming, resulting in expensive sodium perrhenate reagents. Therefore, a method for preparing sodium perrhenate with low cost and short preparation cycle is needed. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art and provide a rapid preparation method for sodium perrhenate. The preparation method comprises the following steps: + or K + With H + H in cationic resin + An exchange reaction is carried out to obtain a perrhenic acid solution, and then sodium borohydride is added to the perrhenic acid to undergo a precipitation reaction to obtain a sodium perrhenate solid, thereby solving the problem of high preparation cost and long cycle caused by the evaporation crystallization process in the prior art for preparing sodium perrhenate.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a rapid preparation method of sodium perrhenate, characterized in that the preparation method comprises the following steps:

[0006] Step 1: dissolve perrhenate in deionized water to obtain a perrhenate solution, and then pass the perrhenate solution through a flask filled with H + The perrhenic acid solution is obtained by using an exchange column of a cationic resin; the perrhenate is ammonium perrhenate or potassium perrhenate, and the H + Type cationic resin is H + C160 resin with large pores, H +Large pore D072 resin and H + One of the gel type 001×7 resins;

[0007] Step 2: Add sodium borohydride to the perrhenic acid solution obtained in step 1, stir, centrifuge and dry to obtain sodium perrhenate solid.

[0008] The present invention utilizes H + The sulfonic acid functional group of cationic resin + With NH4 in ammonium perrhenate or potassium perrhenate + or K + An ion exchange reaction occurs, and the reaction formula is as follows:

[0009] [Matrix-SO3 － ·H + ]+NH4ReO4=[Matrix-SO3 － NH4 + ]+HReO4 or [Matrix-SO3 － ·H + ]+KReO4=[Matrix-SO3 － ·K + ]+HReO4;

[0010] Among them, Matrix is ​​H + The matrix of the cationic resin;

[0011] By mixing the NH4 in ammonium perrhenate and potassium perrhenate + and K + Remove to obtain pure perrhenic acid solution, avoiding residual NH4 in the subsequent synthesized sodium perrhenate solid + and K + ; Then, sodium borohydride and perrhenic acid are added to carry out rhenium precipitation reaction, and the reaction formula is as follows:

[0012] HReO4(aq)+NaBH4(s)+3H2O=NaReO4(s)+H3BO3(aq)+4H2(g);

[0013] Sodium perrhenate precipitate can be directly obtained without evaporation and crystallization, and finally sodium perrhenate solid with good crystallinity can be obtained by centrifugal filtration.

[0014] The above-mentioned rapid preparation method of sodium perrhenate is characterized in that the mass concentration of the ammonium perrhenate dissolved in deionized water in step 1 is 25g / L to 50g / L, and the mass concentration of the potassium perrhenate dissolved in deionized water is 5g / L to 10g / L.

[0015] The invention controls the mass concentration of the perrhenate solution so that the perrhenate solution is close to a saturated state, which is beneficial to synthesizing a high-concentration perrhenic acid solution, thereby promoting the sodium borohydride rhenium precipitation reaction to proceed to the right, and obtaining sodium perrhenate.

[0016] The above-mentioned method for rapid preparation of sodium perrhenate is characterized in that the perrhenate solution in step 1 flows through a container filled with H + The flow rate of the exchange column of the cationic resin is 3BVs / h to 5BVs / h, and the perrhenate solution and the H + The volume ratio of the cationic resin is 10:1 to 20:1.

[0017] The present invention ensures that the resin can completely remove NH4 by controlling the exchange flow rate and the volume ratio of the solution to the resin. + and K + , which is beneficial to the synthesis of high-purity perrhenic acid solution and the elimination of NH4 + and K + Adverse effects on the synthesis of sodium perrhenate.

[0018] The above-mentioned method for rapid preparation of sodium perrhenate is characterized in that the mass ratio of the sodium borohydride in step 2 to the perrhenate in step 1 is 1:1 to 2.5:1.

[0019] The present invention can ensure the rhenium precipitation effect and avoid reagent waste by controlling the amount of sodium borohydride used.

[0020] The above-mentioned rapid preparation method of sodium perrhenate is characterized in that the stirring time in step 2 is 1h to 4h, and the stirring temperature is 15°C to 30°C.

[0021] The invention can ensure that the rhenium in the solution is completely precipitated by controlling the time and temperature of the rhenium precipitation reaction, and can inhibit the rapid decomposition of sodium borohydride by controlling the reaction temperature to avoid bubbling.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1. The present invention converts NH4 in perrhenate into + or K + With H + H in cationic resin + An exchange reaction is carried out to obtain a perrhenic acid solution, and then sodium borohydride is added to the perrhenic acid for precipitation reaction to obtain a sodium perrhenate solid. Compared with the traditional evaporation crystallization process, the process has the advantages of low energy consumption, short time consumption, no irritating NH3 gas emission and good crystallinity of sodium perrhenate, which effectively reduces the production cost and preparation cycle of sodium perrhenate and is conducive to industrial production.

[0024] 2. The present invention can use ammonium perrhenate or potassium perrhenate as raw materials to prepare sodium perrhenate. Compared with the traditional evaporation crystallization process, potassium perrhenate is added as a raw material to avoid a single source of raw materials.

[0025] 3. The present invention controls the parameters such as the amount of raw materials, reaction time and reaction temperature during the preparation process, which is conducive to promoting the ion exchange reaction and the rhenium precipitation reaction to be complete, thereby improving the yield and purity of sodium perrhenate.

[0026] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 1 is the XRD pattern of the sodium perrhenate solid prepared in Example 1 of the present invention.

[0028] Figure 2 This is a microscopic morphology of the sodium perrhenate solid prepared in Example 1 of the present invention.

[0029] Figure 3 This is an energy spectrum analysis diagram of the sodium perrhenate solid prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0030] Example 1

[0031] The preparation method of this embodiment comprises the following steps:

[0032] Step 1: Dissolve 25 g of ammonium perrhenate in 1000 mL of deionized water to obtain an ammonium perrhenate solution, and then flow the ammonium perrhenate solution through a 50 mL H + The exchange column of macroporous C160 resin is used to obtain a perrhenic acid solution;

[0033] Step 2: Add 25 g of sodium borohydride to the perrhenic acid solution obtained in step 1, stir at 15° C. for 1 hour, and then centrifuge and dry to obtain sodium perrhenate solid.

[0034] In this embodiment, H + The macroporous C160 resin can also be replaced by H + Large pore type D072 resin or H + Type gel type 001×7 resin.

[0035] The sodium perrhenate solid prepared in this example was subjected to XRD analysis, and the results were as follows: Figure 1 As shown, the obtained sodium perrhenate solid phase is tetragonal NaReO4, and the X-ray diffraction peak is sharp, indicating that the sodium perrhenate solid has good crystallinity.

[0036] The sodium perrhenate solid prepared in this example was subjected to microscopic morphology and energy spectrum analysis, and the results are as follows: Figure 2 and Figure 3 As shown, the morphology of the sodium perrhenate solid is irregular rhombus particles, and the mass percentages of Na, Re, and O elements are 0.09%, 90.02%, and 9.89%, respectively.

[0037] In summary, the product prepared in this embodiment is sodium perrhenate with good crystallinity and high purity.

[0038] Example 2

[0039] The preparation method of this embodiment comprises the following steps:

[0040] Step 1: Dissolve 35 g of ammonium perrhenate in 1000 mL of deionized water to obtain an ammonium perrhenate solution, and then flow the ammonium perrhenate solution through a 100 mL H + The exchange column of macroporous C160 resin is used to obtain a perrhenic acid solution;

[0041] Step 2: Add 70 g of sodium borohydride to the perrhenic acid solution obtained in step 1, stir at 20° C. for 2 h, and then centrifuge and dry to obtain sodium perrhenate solid.

[0042] After testing, the solid phase of sodium perrhenate prepared in this example is tetragonal NaReO4, and the X-ray diffraction peak is sharp, with good crystallinity.

[0043] Example 3

[0044] The preparation method of this embodiment comprises the following steps:

[0045] Step 1: Dissolve 50 g of ammonium perrhenate in 1000 mL of deionized water to obtain an ammonium perrhenate solution, and then flow the ammonium perrhenate solution through a 62.5 mL H + The exchange column of macroporous C160 resin is used to obtain a perrhenic acid solution;

[0046] Step 2: Add 75 g of sodium borohydride to the perrhenic acid solution obtained in step 1, stir at 30° C. for 4 h, and then centrifuge and dry to obtain sodium perrhenate solid.

[0047] After testing, the solid phase of sodium perrhenate prepared in this example is tetragonal NaReO4, and the X-ray diffraction peak is sharp, with good crystallinity.

[0048] Example 4

[0049] The preparation method of this embodiment comprises the following steps:

[0050] Step 1: Dissolve 10 g of potassium perrhenate in 1000 mL of deionized water to obtain a potassium perrhenate solution, and then flow the potassium perrhenate solution through a 100 mL H2O2 tank at a flow rate of 3 BVs / h. + The exchange column of macroporous C160 resin is used to obtain a perrhenic acid solution;

[0051] Step 2: Add 25 g of sodium borohydride to the perrhenic acid solution obtained in step 1, stir at 30° C. for 4 h, and then centrifuge and dry to obtain sodium perrhenate solid.

[0052] After testing, the solid phase of sodium perrhenate prepared in this example is tetragonal NaReO4, and the X-ray diffraction peak is sharp, with good crystallinity.

[0053] Example 5

[0054] The preparation method of this embodiment comprises the following steps:

[0055] Step 1: Dissolve 5 g of potassium perrhenate in 1000 mL of deionized water to obtain a potassium perrhenate solution, and then flow the potassium perrhenate solution through a 50 mL H + The exchange column of macroporous C160 resin is used to obtain a perrhenic acid solution;

[0056] Step 2: Add 10 g of sodium borohydride to the perrhenic acid solution obtained in step 1, stir at 20° C. for 3 h, and then centrifuge and dry to obtain sodium perrhenate solid.

[0057] After testing, the solid phase of sodium perrhenate prepared in this example is tetragonal NaReO4, and the X-ray diffraction peak is sharp, with good crystallinity.

[0058] Example 6

[0059] The preparation method of this embodiment comprises the following steps:

[0060] Step 1: Dissolve 8 g of potassium perrhenate in 1000 mL of deionized water to obtain a potassium perrhenate solution, and then flow the potassium perrhenate solution through a 100 mL H2O2 container at a flow rate of 5 BVs / h. + The exchange column of macroporous C160 resin is used to obtain a perrhenic acid solution;

[0061] Step 2: Add 8 g of sodium borohydride to the perrhenic acid solution obtained in step 1, stir at 15° C. for 1 hour, and then centrifuge and dry to obtain sodium perrhenate solid.

[0062] After testing, the solid phase of sodium perrhenate prepared in this example is tetragonal NaReO4, and the X-ray diffraction peak is sharp, with good crystallinity.

[0063] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A rapid preparation method of sodium perrhenate, characterized in that: The preparation method comprises the following steps: Step 1: dissolve perrhenate in deionized water to obtain a perrhenate solution, and then pass the perrhenate solution through a flask filled with H + The perrhenic acid solution is obtained by using an exchange column of a cationic resin; the perrhenate is ammonium perrhenate or potassium perrhenate, and the H + Type cationic resin is H + C160 resin with large pores, H + Large pore D072 resin and H + One of the gel type 001×7 resins; Step 2: Add sodium borohydride to the perrhenic acid solution obtained in step 1, stir, centrifuge and dry to obtain sodium perrhenate solid.

2. The rapid preparation method of sodium perrhenate according to claim 1, characterized in that: In step 1, the mass concentration of ammonium perrhenate dissolved in deionized water is 25 g / L to 50 g / L, and the mass concentration of potassium perrhenate dissolved in deionized water is 5 g / L to 10 g / L.

3. The rapid preparation method of sodium perrhenate according to claim 1, characterized in that: In step 1, the perrhenate solution is passed through a flask filled with H + The flow rate of the exchange column of the cationic resin is 3BVs / h to 5BVs / h, and the perrhenate solution and H + The volume ratio of the cationic resin is 10:1 to 20:

1.

4. The rapid preparation method of sodium perrhenate according to claim 1, characterized in that: The mass ratio of the sodium borohydride in step 2 to the perrhenate in step 1 is 1:1 to 2.5:

1.

5. The rapid preparation method of sodium perrhenate according to claim 1, characterized in that: The stirring time in step 2 is 1 h to 4 h, and the stirring temperature is 15° C. to 30° C.

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