Synthesis method of stable isotope 15N, 2H, 18O labeled ammonium nitrate

Abstract

The invention relates to a synthesis method of stable isotope 15N, 2H and 18O labeled ammonium nitrate, which comprises the following steps: adding D218O into 15N labeled ammonium nitrate in a stirring state, adding an ionic liquid supported metal catalyst, stirring for reaction, filtering, concentrating and drying to obtain stable isotope 15N, 2H and 18O labeled ammonium nitrate solid powder. Compared with the prior art, the method can solve the problems of tedious process steps, low isotope utilization rate and the like in the prior art.

Description

Technical Field

[0001] The invention belongs to the technical field of isotope labeled ammonium nitrate and relates to a stable isotope 15 N. 2 H. 18 Synthesis method of O-labeled ammonium nitrate. Background Art

[0002] Isotopes are two or more atoms of the same chemical element with the same atomic number, occupying the same position in the periodic table, and having almost the same chemical behavior, but with different atomic weights or mass numbers, resulting in differences in mass spectrometry behavior, radioactive transformation, and physical properties (such as diffusion capacity in the gaseous state). Isotope atoms are introduced into compound molecules by chemical synthesis, biosynthesis, isotope exchange, etc., and due to the increase in molecular weight and bond energy of isotope atoms, the density, stability and other properties of the compound may undergo certain changes.

[0003] The production of natural abundance ammonium nitrate mainly adopts the neutralization method of nitric acid and ammonia, and the conversion method using ammonium carbonate and calcium nitrate as raw materials. The neutralization method usually has a reaction pressure of 0.12-0.2MPa and a reaction temperature of 120-130°C; in the recently invented patents, most of them focus on the synthesis process of ammonia and the synthesis process using ammonia as raw material, such as CN202110086695.X proposed a method for preparing ammonium nitrate using ammonia water as raw material, hydrogen peroxide as oxidant, and tungsten-containing compounds as catalysts.

[0004] In the neutralization process of naturally abundant ammonium nitrate, nitric acid with a concentration of 50% to 68% or more is usually used, which leads to a violent exothermic reaction, imposes strict requirements on the equipment, and is prone to explosion accidents. In addition, the raw material nitric acid used in the neutralization method is generally prepared by ammonia catalytic oxidation, which has harsh reaction conditions and explosion hazards. The conversion method uses calcium nitrate tetrahydrate, a byproduct of the production process of nitrophosphate fertilizer, as a raw material, and reacts with ammonium carbonate solution to generate ammonium nitrate and calcium carbonate precipitation. Due to raw material limitations, it is rarely used and produces calcium carbonate waste. The hydrogen peroxide method is to oxidize ammonia with hydrogen peroxide in the presence of catalysts such as sodium tungstate, phosphotungstic acid, silicotungstic acid and tungstic acid to generate nitric acid, which then reacts with ammonia water to generate ammonium nitrate. A tungsten-containing catalyst is required in the reaction process, and a two-step reaction is required.

[0005] The current preparation process of oxygen-18 labeled ammonium nitrate requires that nitric acid and oxygen-18 labeled water be reacted at 50-80°C for 1-10 days to prepare oxygen-18 labeled ammonium nitrate crystals. This process requires three steps of reaction: exchange reaction, neutralization reaction, and vacuum distillation. The disadvantage of this process is that the steps are relatively cumbersome, there are problems such as long reaction cycle and low isotope utilization.

[0006] For example, refer to the natural abundance ammonium nitrate preparation process to prepare high abundance stable isotopes 15 N. 2 H. 18 O-labeled ammonium nitrate requires the preparation of deuterated ammonia, oxygen-18-labeled nitric acid, and 15 N-labeled nitric acid, then prepared using the natural abundance ammonium nitrate synthesis process 15 N. 2 H. 18 O-labeled ammonium nitrate has the problems of complicated process steps, low isotope utilization rate and easy dilution of isotope abundance. Summary of the invention

[0007] The purpose of the present invention is to provide a stable isotope 15 N. 2 H. 18 The invention discloses a method for synthesizing O-labeled ammonium nitrate to solve at least one of the problems in the prior art, such as complicated process steps, low isotope utilization rate, and low isotope utilization rate.

[0008] The purpose of the present invention can be achieved by the following technical solutions:

[0009] A stable isotope 15 N. 2 H. 18 The synthesis method of O-labeled ammonium nitrate 15 N-labeled ammonium nitrate was added to D 2 18 O, then add ionic liquid-supported metal catalyst, stir the reaction, filter, concentrate, and dry to obtain stable isotopes 15 N. 2 H. 18 O marks ammonium nitrate solid powder.

[0010] Furthermore, 15 N-labeled ammonium nitrate and D 2 18 The molar ratio of O is 1:(3-60). Preferably, 15 N-labeled ammonium nitrate and D 2 18 The molar ratio of O is 1:(6-40), more preferably 1:10-40.

[0011] Furthermore, the metal in the ionic liquid-supported metal catalyst is Pd, Cu, Ru, Fe or Co.

[0012] Furthermore, the amount of the ionic liquid-supported metal catalyst added is 15 N-labeled ammonium nitrate (1-5) wt%.

[0013] Furthermore, the stirring reaction time is 20 to 30 hours.

[0014] Furthermore, the stirring reaction time is 22 to 25 hours.

[0015] Furthermore, the stirring reaction temperature is room temperature.

[0016] Due to the key difficulties of the synthesis process of isotope reagents, such as the particularity of available raw materials and the easy dilution of isotope abundance, the preparation process of natural abundance ammonium nitrate is not suitable for the preparation of high-abundance stable isotopes. 15 N. 2 H. 18 O-labeled ammonium nitrate. At the same time, the applicant has found through research that isotope exchange reaction is a reversible equilibrium reaction between two atoms of the same isotope. In order to increase the atomic exchange rate and make the exchange reaction reach equilibrium in a shorter time, it is necessary to comprehensively consider the isotope atomic feed ratio, reaction temperature, catalyst system and reaction time. Therefore, the present invention uses an ionic liquid-supported metal catalyst. 16 O and 18 When O atoms are exchanged in the pore structure of the catalyst with the diameter of oxygen atoms, 1 H and 2 H can undergo proton transfer on the metal surface, thereby completing the simultaneous exchange of hydrogen and oxygen elements. The exchange reaction can directly complete the exchange of isotope atoms at room temperature, thereby ensuring the full exchange of isotope atoms. This shortens the reaction time, has the advantages of short process steps and high isotope utilization.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) The present invention designs a stable isotope 15 N. 2 H. 18 The synthesis method of O-labeled ammonium nitrate can complete the exchange in just one step, and the process has the advantages of simple operation process and short steps.

[0019] (2) The present invention can be completed at room temperature without heating or pressurizing the reaction, and the reaction conditions are mild and the reaction process is easy to control. DETAILED DESCRIPTION

[0020] The present invention is described in detail below in conjunction with specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0021] In the following embodiments, the 15 NH 415 NO 3 , D 2 18 O are all commercially available products, among which 15 NH 4 15 NO 3 Purchased from Shanghai Chemical Industry Research Institute Co., Ltd. (www.shanghaisi.com), with an abundance of 99atom% 15 N; D 2 18 O was purchased from Merck Chemical Technology (Shanghai) Co., Ltd. with an abundance of 99atom%D, 95atom% 18 O. The ionic liquid-supported metal catalyst was prepared by referring to the literature "Carbonylation of aromatic halides catalyzed by nano-palladium supported on ionic liquid" (Lin Qi, Fu Haiyan, Yuan Maolin, et al. Carbonylation of aromatic halides catalyzed by nano-palladium supported on ionic liquid [J]. Acta Physico-Chimica Sinica, 2006, 22(10), 1272-1276).

[0022] The rest of the raw materials or processing techniques, unless otherwise specified, are conventional commercially available raw materials or conventional processing techniques in the art.

[0023] Embodiment 1:

[0024] 20.51 g (0.25 mol) 15 N-labeled ammonium nitrate ( 15 NH 4 15 NO 3 ) was added with stirring to 16.52 g (0.75 mol) of deuterium and oxygen 18 labeled water (D 2 18 O), and then add 0.85 g of ionic liquid-supported Pd catalyst. Stir the reaction at room temperature for 24 hours, filter, concentrate, and dry to obtain a stable isotope 15 N. 2 H. 18 O-labeled ammonium nitrate solid powder 18.45g, reaction yield 80.2%, isotope abundance 99.1atom% 15 N, 82.2atom%D, 50.4atom% 18 O.

[0025] Embodiment 2:

[0026] Compared with Example 1, most of them are the same, except that D 2 18 O is 66.06g (3mol), and the stable isotope is prepared 15 N. 2 H. 18O-labeled ammonium nitrate solid powder 20.29g, reaction yield 88.2%, isotope abundance 99.1atom% 15 N, 92.2atom%D, 89.6atom% 18 O.

[0027] Embodiment 3:

[0028] Compared with Example 1, most of them are the same, except that D 2 18 O is 220.2g (10mol), and the stable isotope is prepared 15 N. 2 H. 18 O-labeled ammonium nitrate solid powder 20.82g, reaction yield 90.5%, isotope abundance 99.1atom% 15 N, 99.1atom%D, 95.0atom% 18 O.

[0029] Embodiment 4:

[0030] Compared with Example 1, most of the above are the same, except that the reaction time is 30 hours and the stable isotope is prepared. 15 N. 2 H. 18 O-labeled ammonium nitrate solid powder 21.97g, reaction yield 95.5%, isotope abundance 99.1atom% 15 N, 93.5atom%D, 90.2atom% 18 O.

[0031] Embodiment 5:

[0032] 20.51 g (0.25 mol) 15 N-labeled ammonium nitrate ( 15 NH 4 15 NO 3 ) was added with stirring to 220.2 g (10 mol) of deuterium and oxygen-18 labeled water (D 2 18 O), and then add 0.85 g of ionic liquid-supported Ru catalyst. Stir the reaction at room temperature for 25 hours, filter, concentrate, and dry to obtain a stable isotope 15 N. 2 H. 18 O-labeled ammonium nitrate solid powder 21.9g, reaction yield 95.2%, isotope abundance 99.1atom% 15 N, 99.2atom%D, 95.0atom% 18 O.

[0033] Embodiment 6:

[0034] Compared with Example 1, most of them are the same, except that D 2 18 O is 165.15 g (7.5 mol), and the stable isotope is prepared 15 N. 2 H. 18 O-labeled ammonium nitrate solid powder 22.03g, reaction yield 95.8%, isotope abundance 99.1atom% 15 N, 98.3atom%D, 92.5atom% 18 O.

[0035] Embodiment 7:

[0036] Compared with Example 1, most of them are the same, except that D 2 18 O is 15 mol, and stable isotopes are prepared 15 N. 2 H. 18 O-labeled ammonium nitrate solid powder 21.8g, reaction yield 94.8%, isotope abundance 99.1atom% 15 N, 99.3atom%D, 95.0atom% 18 O.

[0037] Embodiment 8-10:

[0038] Compared with Example 1, most of the above are the same, except that the ionic liquid-supported metal catalyst is adjusted to equal masses of ionic liquid-supported Cu catalyst, ionic liquid-supported Fe catalyst, and ionic liquid-supported Co catalyst. 15 N. 2 H. 18 The solid powders of O-labeled ammonium nitrate were 21.9 g, 21.83 g, and 21.94 g, respectively. The reaction yields were 95.2%, 94.9%, and 95.4%, respectively. The isotopic abundances were 99.1 atom% 15 N, 99.2atom%D, 95.0atom% 18 O; 99.1atom% 15 N, 99.2atom%D, 95.0atom% 18 O; 99.1atom% 15 N, 99.1atom%D, 95.0atom% 18 O.

[0039] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A stable isotope 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: Will 15 N-labeled ammonium nitrate was stirred and D2 18 O, then add ionic liquid-supported metal catalyst, stir the reaction, filter, concentrate, and dry to obtain stable isotopes 15 N. 2 H. 18 O marks ammonium nitrate solid powder.

2. A stable isotope according to claim 1 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: 15 N-labeled ammonium nitrate and D2 18 The molar ratio of O is 1:(3~60).

3. A stable isotope according to claim 1 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: 15 N-labeled ammonium nitrate and D2 18 The molar ratio of O is 1:(6~40).

4. A stable isotope according to claim 1 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: The metal in the ionic liquid-supported metal catalyst is Pd, Cu, Ru, Fe or Co.

5. A stable isotope according to claim 1 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: The amount of the ionic liquid-supported metal catalyst added is 15 N marks 1 to 5 wt% of ammonium nitrate.

6. A stable isotope according to claim 1 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: The stirring reaction time is 20 to 30 hours.

7. A stable isotope according to claim 1 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: The stirring reaction time is 22 to 25 hours.

8. A stable isotope according to claim 1 15 N. 2 H. 18 The method for synthesizing O-labeled ammonium nitrate is characterized in that: The stirring reaction temperature was room temperature.