Process for synthesizing ammonia based on complex-state hydrogen anions
Through the process of using complex hydrogen negative ions to activate nitrogen to generate ammonia under normal pressure and low temperature conditions, the existing synthetic ammonia process has solved the problems of high energy consumption and environmental pollution, and achieved clean and efficient ammonia synthesis.
Patent Information
- Application Number
- CN202510308764.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-17
- Publication Date
- 2025-06-17
AI Technical Summary
The existing synthetic ammonia process requires high temperature and high pressure conditions, consumes a large amount of fossil energy, resulting in high energy consumption and serious environmental pollution.
The ammonia synthesis process based on complex hydrogen negative ions is adopted, and complex hydrogen negative ions are formed in the reactor by metals and organic acids, which directly activate nitrogen to generate ammonia, and the reaction is driven by renewable energy.
It realizes efficient synthesis of ammonia under normal pressure and low temperature conditions, reduces energy consumption and environmental pollution, and has the advantages of low equipment investment, clean and environmentally friendly and suitable for regional production.
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Figure CN120157155A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of energy chemistry, and particularly relates to an ammonia synthesis process based on complex hydride anions. Background Art
[0002] Nitrogen is extremely abundant in the atmosphere, but due to its strong nitrogen-nitrogen triple bond, it is difficult to be converted into utilizable substances. Nitrogen is a key element indispensable for the growth of animals and plants. Since the 20th century, with the rapid growth of the population, the demand for food has increased significantly. Therefore, nitrogen fixation technology has become particularly important.
[0003] Currently, the industrial synthesis of ammonia mainly uses the Haber-Bosch process, which needs to be carried out under high temperature and high pressure (400 - 500 °C, 20 - 50 MPa). This process consumes 1 - 2% of the global total energy, and the required hydrogen is derived from fossil energy, which leads to a large amount of carbon dioxide emissions and causes serious environmental problems. Using hydride anions (H-) in metal hydrides to activate nitrogen is one of the methods to replace the traditional Haber-Bosch process for ammonia formation. However, at present, simply using the lattice hydrogen (H*) in metal hydride crystals often cannot directly activate nitrogen, and external stimuli such as light and electricity or catalysts are needed to provide power for chemical reactions, and the efficiency is low. Therefore, the present invention proposes an ammonia synthesis process based on complex hydride anions. Summary of the Invention
[0004] The purpose of the present invention is to provide an ammonia synthesis process based on complex hydride anions, aiming to solve the problems raised in the above background art.
[0005] The purpose of the present invention is achieved through the following technical solutions:
[0006] An ammonia synthesis process based on complex hydride anions, the ammonia synthesis process synthesizes ammonia based on complex hydride anions in solution, and the reaction is divided into two steps:
[0007] Step 1: Add reactants and reaction solution into a reactor, heat and introduce nitrogen to generate ammonia and product A; introduce high-purity nitrogen into the reactor, and the complex hydride anion (Hc - ) fixes nitrogen. If the hydride is Li and the reaction solution is oleic acid, the reaction process is as follows: 1) Li + C 17 H 33 COOH → LiHc - , 2) LiHc - + N2 → NH3. Other metals will undergo similar reactions.
[0008] Step 2: Reduce product A electrochemically or thermochemically; Use clean energy such as solar energy, wind energy, and nuclear energy to generate electricity, and use the obtained electric energy to reduce the product after the reaction to achieve raw material recycling. If the reactant is Li and the reaction solution is oleic acid, the reaction process is C 17 H 33 COOLi → Li + C 17 H 33 COOH.
[0009] The reactant is one or more of metals, metal hydrides, metal alloys, and metal alloy hydrides.
[0010] The reaction solution is one or more of organic acids, inorganic acids, and alcohols.
[0011] Further, the main group metal elements of the reactant are one or more of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, B, and Al; the transition metals of the reactant are one or more of the rare earth metal group and Ti, Zr, Hf, V, Nb, Ta, and Pd;
[0012] The inorganic acid is one or more of hydrochloric acid, sulfuric acid, hydrobromic acid, hydroiodic acid, hydrofluoric acid, hydrosulfuric acid, carbonic acid, phosphoric acid, boric acid, silicic acid, arsenic acid, antimonous acid, titanic acid, tungstic acid, stannic acid, and zincic acid with different concentrations; the organic acid is one or more of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, palmitic acid, stearic acid, palmitoleic acid, linoleic acid, linolenic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, citric acid, malic acid, tartaric acid, benzoic acid, o-hydroxybenzoic acid, terephthalic acid, and caffeic acid with different purities; the alcohols are alcohols that can provide protons, one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, tert-butanol, allyl alcohol, propargyl alcohol, cyclohexanol, benzyl alcohol, ethylene glycol, glycerol, and pentaerythritol.
[0013] Further, the temperature for performing Step 1 in the reactor is 50 - 500 °C, preferably 100 - 300 °C; the reaction time for both Step 1 and Step 2 is more than 10 min.
[0014] Further, the reaction tail gas flowing out of the reactor is introduced into an ammonia absorption device for absorption, and the remaining gas is returned to the reactor for cyclic conversion.
[0015] Further, the ammonia absorption material used in the ammonia absorption device is one or more of alkali metal halides, alkaline earth metal halides, transition metal halides, solid acids, activated carbon, and molecular sieves.
[0016] Further, the alkali metal halide is one or more of LiI, LiBr, and LiCl; the alkaline earth metal halide is one or more of CaI2, MgI2, SrI2, CaBr2, MgBr2, SrBr2, CaCl2, MgCl2, SrCl2, CaF2, MgF2, and SrF2; the transition metal halide is one or more of MnCl2, FeCl2, NiCl2, CoCl2, SnCl2, MnBr2, FeBr2, NiBr2, CoBr2, SnBr2, MnI2, FeI2, NiI2, CoI2, and SnI2.
[0017] Further, the ammonia absorbed by the ammonia-absorbing material is released by heating, and the temperature is 40 - 500 °C, preferably 100 - 300 °C.
[0018] Further, the high-purity nitrogen gas introduced into the reactor is obtained from air by pressure swing adsorption or membrane separation.
[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0020] The present invention provides a process for synthesizing ammonia at normal pressure and low temperature by using renewable energy as the energy source and forming a complex hydride anion (Hc-) structure. This process utilizes the reactants and the reaction solution to form complex hydride anions in the reactor, directly activating and hydrogenating nitrogen gas to generate ammonia, without relying on external stimuli such as light and electricity or catalysts to provide the reaction driving force. It has the advantages of low equipment investment (no need for large-scale equipment), clean and environmentally friendly (not relying on fossil energy and having no CO2 emissions throughout the process), mild conditions (operating at normal pressure and low temperature, without high-temperature and high-pressure conditions), and being suitable for regional production. Driven by renewable energy and combined with the efficient reaction characteristics of complex hydride anions, this process realizes the green and efficient synthesis of ammonia, is an environmentally friendly ammonia synthesis process, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is the process flow chart of the present invention. DETAILED DESCRIPTION OF THE INVENTION
[0022] In order to have a clearer understanding of the technical features, objectives, and beneficial effects of the present invention, the technical solutions of the present invention will be described in detail below, but it should not be construed as a limitation on the implementable scope of the present invention.
[0023] The following describes the specific implementation of the present invention in detail with specific embodiments.
[0024] Example 1: Take 0.07 mg of metallic lithium in a reactor. Take 5 ml of oleic acid and purge with nitrogen N2 for 1 min, then transfer the mixture into the reactor and start heating. The reaction temperature is controlled at 150 °C (it is active when the temperature exceeds 100 °C, and the yield is the highest at 150 °C). During the process, nitrogen N2 is continuously introduced, and the gas flow rate is controlled at 30 ml / min. Unless otherwise specified, all operations are carried out using standard Schlenk techniques or glove box techniques under a nitrogen or argon atmosphere. The reaction tail gas is directly passed into a container filled with MgI2, and the gas passing through MgI2 is introduced into a conductivity meter. When the conductivity does not change, it indicates that all ammonia has been absorbed. After continuously introducing nitrogen for 1 h, the average rate of ammonia synthesis is calculated to be 2080 mmol / g by weighing the weight gain of MgI2 Li / h.
[0025] Example 2: Take 0.08 mg of lithium hydride powder in a reactor. Take 5 ml of oleic acid and purge with nitrogen N2 for 1 min, then transfer the mixture into the reactor and start heating. The reaction temperature is controlled at 150 °C (it is active when the temperature exceeds 100 °C, and the yield is the highest at 150 °C). During the process, nitrogen N2 is continuously introduced, and the gas flow rate is controlled at 30 ml / min. On the other side of the reactor, the generated gas is introduced into a 0.1 mol / L dilute sulfuric acid solution to absorb the gas generated in the experiment. Unless otherwise specified, all operations are carried out using standard Schlenk techniques or glove box techniques under a nitrogen or argon atmosphere. The reaction tail gas is directly passed into a container filled with MgI2, and the gas passing through MgI2 is introduced into a conductivity meter. When the conductivity does not change, it indicates that all ammonia has been absorbed. After continuously introducing nitrogen for 1 h, the average rate of ammonia synthesis is calculated to be (1000 - 1200) mmol / g by weighing the weight gain of MgI2 LiH / h.
[0026] Example 3: Take 0.23 mg of metallic Na in a reactor. Take 5 ml of oleic acid and purge with nitrogen N2 for 1 min, then transfer the mixture into the reactor and start heating. The reaction temperature is controlled at 250 °C (it is active when the temperature exceeds 200 °C, and the yield is the highest at 250 °C). During the process, nitrogen N2 is continuously introduced, and the gas flow rate is controlled at 30 ml / min. On the other side of the reactor, the generated gas is introduced into a 0.1 mol / L dilute sulfuric acid solution to absorb the gas generated in the experiment. Unless otherwise specified, all operations are carried out using standard Schlenk techniques or glove box techniques under a nitrogen or argon atmosphere. The reaction tail gas is directly passed into a container filled with MgI2, and the gas passing through MgI2 is introduced into a conductivity meter. When the conductivity does not change, it indicates that all ammonia has been absorbed. After continuously introducing nitrogen for 1 h, the average rate of ammonia synthesis is calculated to be (600 - 850) mmol / g by weighing the weight gain of MgI2 Na / h.
[0027] Example 4: Take 0.49 mg of metallic K in a reactor. Take 5 ml of oleic acid and purge with nitrogen N2 for 1 min, then transfer the mixture to the reactor and start heating. The reaction temperature is controlled at 250 °C (it is active when the temperature exceeds 200 °C and the yield is the highest at 250 °C). During the process, nitrogen N2 is continuously introduced, and the gas flow rate is controlled at 30 ml / min. On the other side of the reactor, the generated gas is introduced into a 0.1 mol / L dilute sulfuric acid solution to absorb the gas generated in the experiment. Unless otherwise specified, all operations are carried out using standard Schlenk techniques or glove box techniques under a nitrogen or argon atmosphere. The reaction tail gas is directly passed into a container filled with MgI2, and the gas passing through MgI2 is introduced into a conductivity meter. When the conductivity does not change, it indicates that all ammonia has been absorbed. After continuously introducing nitrogen for 1 h, the average rate of ammonia synthesis is calculated by weighing the weight gain of MgI2 to be (300 - 500) mmol / g K / h.
[0028] The above are only the preferred embodiments of the present invention. It should be noted that for those skilled in the art, without departing from the concept of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent.
Claims
1. A process for synthesizing ammonia based on complexed hydrogen ions, characterized in that: The ammonia synthesis process is based on the synthesis of ammonia by complexed hydrogen anions in solution, and the reaction is divided into two steps: Step 1: Add the reactants and the reaction liquid into a reactor, heat and introduce nitrogen to generate ammonia and product A; Step 2: Reducing product A by electrochemical or thermochemical means; The reactant is one or more of a metal, a metal hydride, a metal alloy and a metal alloy hydride; The reaction liquid is one or more of organic acid, inorganic acid and alcohol.
2. The process for synthesizing ammonia according to claim 1, characterized in that: The main group metal element of the reactant is one or more of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, B, and Al; the transition metal of the reactant is one or more of the rare earth metal group and Ti, Zr, Hf, V, Nb, Ta, and Pd; The inorganic acid is one or more of hydrochloric acid, sulfuric acid, hydrobromic acid, hydroiodic acid, hydrofluoric acid, hydrosulfuric acid, carbonic acid, phosphoric acid, boric acid, silicic acid, arsenic acid, antimonic acid, titanic acid, tungstic acid, stannic acid and zincic acid of different concentrations; the organic acid is one or more of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, palmitic acid, stearic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, citric acid, malic acid, tartaric acid, benzoic acid, o-hydroxybenzoic acid, terephthalic acid and caffeic acid of different purity; the alcohol is one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, tert-butanol, allyl alcohol, propargyl alcohol, cyclohexanol, benzyl alcohol, ethylene glycol, glycerol and pentaerythritol.
3. The process for synthesizing ammonia according to claim 1, characterized in that: The temperature for carrying out step 1 in the reactor is 50-500° C.; the reaction time for steps 1 and 2 is both more than 10 minutes.
4. The process for synthesizing ammonia according to claim 1, characterized in that: The reaction tail gas flowing out of the reactor is passed into an ammonia absorption device for absorption, and the remaining gas is returned to the reactor for cyclic conversion.
5. The process for synthesizing ammonia according to claim 4, characterized in that: The ammonia absorbing material used in the ammonia absorbing device is one or more of alkali metal halides, alkaline earth metal halides, transition metal halides, solid acids, activated carbon and molecular sieves.
6. The process for synthesizing ammonia according to claim 5, characterized in that: The alkali metal halide is one or more of LiI, LiBr and LiCl; the alkaline earth metal halide is one or more of CaI2, MgI2, SrI2, CaBr2, MgBr2, SrBr2, CaCl2, MgCl2, SrCl2, CaF2, MgF2 and SrF2; the transition metal halide is one or more of MnCl2, FeCl2, NiCl2, CoCl2, SnCl2, MnBr2, FeBr2, NiBr2, CoBr2, SnBr2, MnI2, FeI2, NiI2, CoI2 and SnI2.
7. The process for synthesizing ammonia according to claim 5, characterized in that: The ammonia absorbed by the ammonia absorbing material is released by heating, and the temperature is 40-500°C.
8. The process for synthesizing ammonia according to claim 1, characterized in that: The nitrogen introduced into the reactor is obtained from the air by pressure swing adsorption or membrane separation.