Reactor comprising nitric acid recycling device

Abstract

The present invention relates to: a nitric acid recycling device for recycling a nitric acid in a reaction process by generating the nitric acid using a nitrogen byproduct that is generated during a nitric acid reaction process for a biomass raw material; and a reactor comprising the nitric acid recycling device. The nitric acid recycling device comprises a first reaction unit that generates nitrogen dioxide from a gas containing nitrogen oxide flowing into a chamber, and a second reaction unit that is provided in the chamber, together with the first reaction unit, and that generates a nitric acid from nitrogen dioxide.

Description

Reactor including a nitric acid recycling device

[0001] The present invention relates to a reactor comprising a nitric acid recycling device for recycling nitric acid into a reaction process by utilizing nitrogen by-products generated in a nitric acid reaction process of biomass raw materials to produce nitric acid.

[0002] Due to continuous population growth and industrial development, petroleum resources are the resource on which humanity relies most heavily, accounting for approximately 95% of currently produced chemicals. However, facing the finite nature of its reserves and the environmental problems inevitably caused by its use, there is an urgent need to find alternatives.

[0003] Consequently, research on various alternative materials capable of replacing petroleum resources has recently emerged. Among these, biomass derived from plant resources that are produced annually in nature—such as corn, sugarcane, lignocellulosic plants, palm, and seaweed—is being highlighted as an important future resource due to its advantages of being not only renewable but also environmentally friendly.

[0004] As such, due to high oil prices and resource depletion, the use of biomass is increasing as a means to replace petroleum resources. Among such biomass, glucose is produced from starchy sources such as potatoes, corn, wheat, barley, rye, and wheat; cereals such as rice; sugar-producing plants such as sugarcane and sugar beets; and lignocellulosic cellulose sources such as wood, grass, and rice straw. Recently, the use of glucose for industrial purposes has been increasing, serving as a substitute fuel for petroleum, as a raw material for bioethanol, and as a raw material for polymer materials. For example, glucose can be utilized as a precursor for various substances such as gluconic acid, lactic acid, and ethanol.

[0005] In particular, glucaric acid, a glucose-derived bio-based chemical, is receiving significant attention due to its wide range of applications and eco-friendly properties. As industries increasingly prioritize sustainability, glucaric acid provides a viable alternative to traditional petrochemical products. Its usage is increasing as it is utilized in various detergents and cleaning agents, concrete mixers, de-icing and corrosion inhibitors, and as a precursor for biodegradable plastics.

[0006] In addition, adipic acid, which can be produced from glucaric acid, can be manufactured into nylon 66, which is utilized in various industrial fields such as automotive parts, electronic components, and industrial machinery. Meanwhile, although adipic acid can be produced through a nitrification process from a mixture generated by the oxidation reaction of petroleum-based cyclohexane rather than biomass, the nitrogen oxides produced during the process of generating adipic acid from petroleum-based raw materials contain a high proportion of N2O gas, posing a problem that requires reaction equipment capable of high temperature or high pressure to treat them. In particular, high-temperature equipment capable of operating at approximately 1,000°C or 2,000°C or higher is required. However, treating nitrogen oxides generated from biomass raw materials has the advantage of requiring relatively lower thermal energy compared to petroleum-based materials, leading to an increasing trend in the utilization of biomass raw materials in manufacturing.

[0007] As such, glucaric acid or adipic acid derived from glucose, a biomass, can be utilized in biomaterials or bioplastics.

[0008] However, in the production process of manufacturing glucose into glucaric acid, nitric acid is used as the main oxidizing agent in the oxidation reaction. The reaction between glucose and nitric acid produces not only glucaric acid but also nitrogen oxides (NOx). In particular, nitrogen oxides such as nitric oxide (NO), nitrogen dioxide (NO2), and nitrous oxide (N2O) are released as by-products during the reaction. These nitrogen oxides are major causes of air pollution and cause environmental problems by contributing to ozone layer depletion and global warming.

[0009] Moreover, there is a problem in that an amount of nitric acid exceeding the appropriate amount relative to the raw material glucose is required, leading to an increase in manufacturing costs. In addition, since nitrogen oxides are pollutants and their emissions are subject to strict regulations, separate exhaust gas purification devices or catalytic systems are required to treat residual nitrogen oxides; this increases the complexity of process equipment and acts as a major cause of high initial investment costs.

[0010] Therefore, in addition to the process of producing glucose into glucaric acid, there is a need for a technical approach to recycle nitric acid from nitrogen oxides as a means to reduce the generation of nitrogen oxides in other biomass-based manufacturing processes or various chemical processes using nitric acid, or to effectively treat them to reduce the emission of nitrogen oxides into the atmosphere, while also reducing equipment and manufacturing costs.

[0011] (Prior Art Literature)

[0012] (Patent Document) Japanese Published Patent No. 2024-503812 (Published Jan. 29, 2004)

[0013] The present invention has been devised to solve the aforementioned problems, and the objective of the present invention is to provide a nitric acid recycling device for reducing the generation of nitrogen oxides or effectively treating them to reduce the emission of nitrogen oxides into the outside air.

[0014] Furthermore, the object of the present invention is to provide a nitric acid recycling device for reducing nitrogen oxides discharged externally from a process in which a nitric acid reaction is performed. That is, the present invention provides a method for recycling nitric acid from a gas stream containing nitrogen oxides.

[0015] Furthermore, the present invention provides a glucaric acid manufacturing facility that can reduce facility and manufacturing costs through nitric acid recycling.

[0016] The nitric acid production apparatus of the present invention for achieving the aforementioned purpose comprises a first reaction unit that generates nitrogen dioxide from a gas containing nitrogen oxides introduced into the interior of a chamber, and a second reaction unit provided in the chamber together with the first reaction unit and that generates nitric acid from the nitrogen dioxide.

[0017] In one embodiment, the first reaction unit includes an oxygen supply connected to a chamber and is characterized by inducing an oxidation reaction by oxygen with respect to nitrogen oxide gas to generate nitrogen dioxide.

[0018] In one embodiment, the first reaction unit further includes a cooling means for cooling the chamber, and is characterized by cooling the chamber to a temperature in the range of -20°C to 25°C by the cooling means.

[0019] In one embodiment, the cooling means includes a cooling coil installed inside the chamber and a cooling jacket installed outside the chamber.

[0020] In one embodiment, the second reaction unit includes a distilled water supply connected to the chamber and is characterized by inducing a nitrification reaction with nitrogen dioxide through mixing with distilled water to produce nitric acid.

[0021] In one embodiment, the second reaction unit further includes a heating means for heating the chamber, and is characterized by heating the chamber to a temperature in the range of 30°C to 150°C by the heating means.

[0022] Meanwhile, the method for producing nitric acid according to the present invention is a method for obtaining nitric acid from nitrogen oxides, comprising an oxidation step of producing nitrogen dioxide by mixing and reacting nitric oxide and oxygen inside a chamber, and a nitrification step of producing nitric acid by mixing and reacting nitrogen dioxide and water inside a chamber.

[0023] In one embodiment, the method for producing nitric acid according to the present invention further includes a circulation step of discharging the internal air of the chamber to the outside of the chamber via a circulation line and recirculating it.

[0024] In one embodiment, the method for producing nitric acid according to the present invention further includes a step of cooling the chamber after the oxidation step.

[0025] In one embodiment, the nitrification step includes the step of introducing distilled water into the chamber and the step of heating the chamber.

[0026] In one embodiment, the step of introducing distilled water further includes at least one of the steps of adjusting the installation angle of a nozzle that sprays distilled water into the chamber, controlling the amount of spray from the nozzle, and controlling the size of the sprayed particulates by adjusting the hole size of the nozzle.

[0027] In one embodiment, the method for producing nitric acid according to the present invention further includes a depressurization step of lowering the internal pressure of the chamber after the chamber is heated.

[0028] Meanwhile, the nitric acid recycling system of the present invention includes a raw material reaction tank that induces an oxidation reaction by introducing nitric acid into a raw material, and a nitric acid production reaction tank connected to the raw material reaction tank for producing nitric acid by reacting nitrogen oxides generated in the raw material reaction tank.

[0029] According to the present invention as described above, since nitric acid can be produced from nitrogen oxides generated during the production of glucaric acid, it is possible to recycle nitric acid that is introduced together with the raw material while simultaneously treating nitrogen oxides.

[0030] Accordingly, the present invention has the advantage of effectively treating nitrogen oxides to minimize their release into the outside air, thereby reducing exhaust gases emitted to the outside, and minimizing manufacturing costs through nitric acid recycling.

[0031] In addition, the present invention can improve the yield by increasing the reaction amount during nitric acid production for nitric acid recycling, and can obtain high-purity nitric acid through a concentration process.

[0032] In addition, since each reaction unit is integrally provided in the chamber, the oxidation process and the nitrification reaction process can be performed separately within the chamber, so there is no need to separately discharge or recover the fluid generated in each process, which provides significant advantages in terms of structure, and in particular, the continuity of each process can be easily maintained, thereby increasing productivity.

[0033] FIG. 1 is a schematic diagram illustrating a glucaric acid manufacturing system including a nitric acid recycling device according to a first embodiment of the present invention for manufacturing glucaric acid, and the diagram is laid flat.

[0034] FIG. 2 is a schematic diagram illustrating a glucaric acid manufacturing system including a nitric acid recycling device according to a second embodiment of the present invention for manufacturing glucaric acid, and the diagram is laid flat.

[0035] Figure 3 is a schematic diagram illustrating the manufacturing process for producing gluconic acid.

[0036] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms.

[0037] Hereinafter, the technical features of the present invention will be specifically described with reference to the attached drawings.

[0038] The present invention relates to a nitric acid recycling device for recycling nitric acid from nitrogen oxides and a reaction system applying the same. Nitrogen oxides (NO X A ) refers to a compound produced by the reaction of nitrogen (N2) and oxygen (O2). Nitrogen oxides (NO X The term ) is used interchangeably to describe a mixture of nitric oxide (NO) and nitrogen dioxide (NO2), where x is 1 or 2. That is, nitrogen oxides contain nitric oxide (NO) or nitrogen dioxide (NO2). The present invention relates to NO generated through the reaction of biomass starch sugar byproduct (Hydrol) and nitric acid. x The purpose is to utilize gas to generate nitric acid for recycling. NO gas is highly reactive and is easily oxidized to form NO2. Then, when NO2 gas reacts with water, it is produced as nitric acid (HNO3 and HNO2). Additionally, N2O4 decomposes into 2NO2 as the temperature rises, and the conversion rate increases as the temperature rises.

[0039] FIGS. 1 and FIGS. 2 respectively illustrate a glucaric acid manufacturing system for producing glucaric acid according to the first and second embodiments, and FIG. 3 schematically illustrates a manufacturing process for producing glucaric acid. In the drawings, the valve installed in each line may be composed of any one of a gate valve, a globe valve, a control valve, a solenoid valve, a check valve, a plug valve, or a cock valve.

[0040] Referring to FIG. 1, according to the present invention, a reaction system including a nitric acid recycling device may include a raw material reactor (100) and a nitric acid generating reactor (200). According to one embodiment, the present invention may be configured as a glucaric acid manufacturing system.

[0041] Here, the raw material reactor (100) may be configured as a main reaction vessel that induces the oxidation reaction of glucose for the production of glucaric acid. A nitrogen oxide discharge line (201) connected to the raw material reactor (100) transfers the nitrogen oxide generated in the raw material reactor (100) to a nitric acid generating reactor (200). The nitric acid generating reactor (200) is intended to process the nitrogen oxide generated in the raw material reactor (100) and may be configured as an auxiliary reaction vessel that generates nitric acid from the nitrogen oxide. At this time, the nitric acid generating reactor (200) is composed of nitrogen oxide (NO x Nitric acid (HNO3) can be produced from ), and the generated nitric acid can be supplied back to the raw material reactor (100) to enable the nitric acid to be recycled.

[0042] Thus, a nitric acid manufacturing device according to one embodiment of the present invention may be provided as a nitric acid generating reactor (200), connected to a raw material reactor (100), and capable of recovering and treating nitrogen oxides generated in the raw material reactor (100) during the production of glucaric acid.

[0043] Below, the nitric acid production device will be described first. The nitric acid production device consists of a part of the nitric acid recycling device.

[0044] As illustrated in FIG. 1, the nitric acid manufacturing apparatus (200) of the present invention may include a chamber (210) of an auxiliary reaction vessel, a first reaction unit (200a) that generates nitrogen dioxide from a gas containing nitrogen oxides introduced into the chamber (210), and a second reaction unit (200b) that is installed in the chamber (210) together with the first reaction unit (200a) and generates nitric acid from nitrogen dioxide. At this time, the first reaction unit (200a) and the second reaction unit (200b) may each include a configuration that performs separate operations rather than being formed as separate spaces. For example, the first reaction unit (200a) may include an oxygen supply unit (220) and a cooling means (230), and the second reaction unit (200b) may be configured to include a distilled water supply unit (240), a heating means (250), and a pressure reduction means (260). Additionally, the nitric acid manufacturing device (200) of the present invention may further include an air circulation device (270).

[0045] In one embodiment, the chamber (210) has an external fluid inlet line (211) that is connected to an external reactor, in this embodiment, a raw material reactor (100), and can introduce a target gas. At this time, the external fluid inlet line (211) is connected to a nitrogen oxide discharge line (201) so that nitrogen oxide gas generated in the raw material reactor (100) can be introduced into the chamber (210). A first reaction section (200a) and a second reaction section (200b) may be provided in such a chamber (210).

[0046] In one embodiment, the first reaction unit (200a) may include an oxygen supply unit (220) connected to a chamber (210). The oxygen supply unit (220) may supply oxygen to the chamber (210). This oxygen supply unit (220) may be equipped with a flow meter or a flow controller (221) to control the amount of oxygen supplied to the chamber (210). Additionally, the oxygen supply unit (220) may be connected to an external fluid inlet line (211) as shown in the drawing, but may also be connected to the chamber (210) through a separate pipe.

[0047] In this way, the first reaction unit (200a) can generate nitrogen dioxide by inducing an oxidation reaction with oxygen on nitrogen oxide gas through the oxygen supply unit (220) by introducing oxygen into the interior of the chamber (210). Accordingly, an oxidation process for nitric oxide can be performed by the first reaction unit (200a).

[0048] In one embodiment, the first reaction unit (200a) may further include a cooling means (230) for cooling the chamber (210). For example, the cooling means (230) may be composed of a refrigerant circulator that introduces cooling water and may include a cooling coil (231) installed inside the chamber (210) and a cooling jacket (232) installed outside the chamber (210). Accordingly, the cooling means (230) can perform a cooling action by circulating cooling water using the respective circulation lines of the cooling coil (231) and the cooling jacket (232).

[0049] The first reaction section (200a) can cool the chamber (210) to a temperature in the range of -20°C to 25°C by means of a cooling means (230).

[0050] Accordingly, the cooling means (230) cools the nitrogen oxide gas, thereby reducing the reactivity of the nitrogen oxide gas. That is, in the case of the oxidation reaction of the nitrogen oxide gas performed in the first reaction section (200a), the reaction rate may be formed more rapidly at high temperatures as it is a temperature-dependent reaction. The cooling means (230) lowers the temperature through cooling to reduce molecular kinetic energy, thereby reducing the collision frequency and reaction possibility, and thus lowering the reaction rate. In particular, since the reactivity may increase at high temperatures when NO and oxygen are mixed, the cooling means (230) can create a stable reaction environment through cooling. In addition, the cooling means (230) can prevent the temperature from rising due to the exothermic reaction generated during the reaction.

[0051] These cooling means (230) can rapidly cool the temperature of the chamber (210), particularly the internal temperature, to a set appropriate temperature as the cooling coil and cooling jacket are installed inside and outside the chamber (210), respectively, to perform a cooling action.

[0052] At this time, the cooling coil performs a cooling action by coming into direct contact with the gases inside the chamber (210), so it is effective for cooling to a desired temperature. In addition, the cooling jacket performs a direct cooling action on the chamber (210) to complement the cooling by the cooling coil.

[0053] In this way, the first reaction section (200a) induces an oxidation reaction of the internal gas, and nitrogen oxide (NO₂) x In particular, nitrogen dioxide (NO2) is generated through a mixed reaction of oxygen (O2) with nitric oxide (NO). At this time, since the existing nitrogen dioxide contained in the nitrogen oxide does not have a specific catalyst, no significant oxidation reaction occurs with oxygen.

[0054] In one embodiment, the first reaction unit (200a) is cooled by a cooling means (230), so that nitrogen dioxide produced through the oxidation reaction and the existing nitrogen dioxide are liquefied by the cooling action and exist in a liquid state, thereby controlling the reactivity. In addition, nitrogen dioxide may exist in different states depending on the temperature conditions, and under low temperature conditions, it exists in a liquid state as N2O4, and when the low temperature conditions are exceeded, it exists in a gaseous state as NO2.

[0055] The nitrogen dioxide generated in this way can be mixed and reacted by the second reaction unit (200b).

[0056] In one embodiment, the second reaction unit (200b) may include a distilled water supply unit (240) connected to the chamber (210).

[0057] The second reaction unit (200b) introduces distilled water into the chamber (210) by means of a distilled water supply unit (240), and can induce a nitrification reaction with nitrogen dioxide through mixing with distilled water to produce nitric acid. A nitrification reaction process involving nitrogen dioxide and water can be performed by the second reaction unit (200b).

[0058] In one embodiment, the distilled water supply unit (240) may include a nozzle (not shown) installed inside the chamber (210) and a distilled water supply pump (241), a distilled water supply pipe (242), and a distilled water tank (243) configured to deliver distilled water to the nozzle. At this time, the nozzle may be installed at the end of the distilled water supply pipe (242) connected to the chamber (210). The distilled water supply pump (241) supplies distilled water stored in the distilled water tank (243) to the nozzle via the distilled water supply pipe (242), and the distilled water can be introduced into the interior of the chamber (210) through the nozzle.

[0059] In the second reaction section (200b), nitrogen dioxide can be mixed with distilled water and produced into nitric acid through a nitrification reaction. In the second reaction section (200b), steam is injected into the interior of the chamber (210) to carry out an initial reaction. Bubbling is induced by the supplied distilled water to induce close contact between nitrogen dioxide and distilled water. At the same time, unreacted nitrogen dioxide is dissolved in water to remove it, and a scrubbing action can be performed to additionally induce a reaction with H2O to form nitric acid.

[0060] At this time, the nozzle may be installed on the upper side of the chamber (210), and the number of nozzles, installation location, installation angle, injection amount, injection speed, and injection shape may be controlled. This is to more effectively induce a mixing reaction with the internal gas when distilled water is injected. For example, the present invention enables the distilled water sprayed by the nozzle to smoothly mix and react with the gas inside the chamber (210) by installing additional nozzles or installing them at various locations along the upper and lower parts or the inner perimeter of the chamber (210). In addition, in either case where the number of nozzles is configured as one or multiple, distilled water is sprayed toward the gas remaining in the chamber (210) or the gas flowing into the chamber (210) from the outside by adjusting the installation angle of the nozzle, or the range of contact with the gas at a predetermined point of spraying is increased by adjusting the spray speed, spray amount, or spray interval, or the shape and size of fine particles are formed differently by adjusting the spray form (direct water inflow method or steam spray method, etc.) by changing the size of the nozzle opening or the spray amount, etc., thereby allowing the gas and distilled water inside the chamber (210) to mix and react smoothly. This control of the nozzle is mainly intended to increase reaction efficiency by maximizing the surface area of ​​the distilled water.

[0061] Meanwhile, when nitrogen dioxide is converted into nitric acid in the second reaction unit (200b), residual H2O may exist in addition to the nitric acid. Accordingly, the present invention can obtain highly concentrated nitric acid by removing the residual H2O. A concentration process for nitric acid can be performed in the second reaction unit (200b). That is, the second reaction unit (200b) can perform heating and depressurization processes for the concentration operation.

[0062] To this end, the second reaction unit (200b) may further include a heating means (250) for heating the chamber (210).

[0063] In one embodiment, the heating means (250) may be composed of a heater or a heat exchanger for heating the chamber (210). For example, the heating means (250) may be implemented as a hot oil bath capable of raising the temperature of the chamber (210) by circulating high-temperature oil, and may heat the chamber (210) while circulating along an oil line installed in the chamber (210).

[0064] The second reaction unit (200b) is characterized by heating the chamber (210) to a temperature in the range of 30°C to 150°C by a heating means (250).

[0065] Accordingly, the second reaction unit (200b) heats the remaining H2O inside the chamber (210) and allows the heated residue to be discharged to the outside. That is, the heating means (250) can separate nitric acid and water by a distillation method while simultaneously rapidly evaporating and removing the water.

[0066] Additionally, the second reaction unit (200b) may further include a pressure reduction means (260).

[0067] In one embodiment, the pressure reduction means (260) may be composed of a pressure regulator or a vacuum pump (261) for regulating the internal pressure of the chamber (210). The pressure reduction means (260) includes a vacuum line (262) connecting the vacuum pump (261) and the chamber (260).

[0068] This vacuum reduction means (260) can lower the boiling point of the residual H2O relatively by lowering the pressure of the chamber (210) to a low pressure, and allows the residual H2O to be easily heated even when the heating means (250) heats the chamber (210) within an appropriate temperature range, thereby enabling efficient separation of nitric acid by vacuum distillation and reducing the amount of water to obtain highly concentrated nitric acid.

[0069] At this time, a cold trap (263) may be installed upstream of the vacuum pump (261), and the pressure reduction means (260) can block the venting of the corresponding substances by condensing various components by the cold trap (263) when the vacuum is vented.

[0070] Thus, the nitric acid manufacturing apparatus of the present invention has the advantage of being able to obtain highly concentrated nitric acid by performing distillation and vacuum distillation processes within a single chamber (210), unlike conventional methods in which the concentration process of nitric acid is performed in multiple reactors arranged in series or parallel.

[0071] In one embodiment, the nitric acid manufacturing apparatus of the present invention may further include an air circulator (270).

[0072] The air circulator (270) may include a circulation fan (271) and an air circulation line (272) connected to the chamber (210). This air circulator (270) can induce air circulation by discharging air inside the chamber (210) to the outside of the chamber (210) via the air circulation line (272) and simultaneously recirculating it. That is, when a reaction is induced by mixing a fluid in a gaseous or liquid state inside the chamber (210) through a stirring action, the mixing action may be poor because the fluidity inside the closed chamber (210) is not high. Therefore, the air circulator (270) of the present invention can improve the mixing reaction effect by increasing the fluidity of the gas inside the chamber (210).

[0073] At this time, the air circulator (270) does not circulate the air inside the chamber (210) only within the chamber (210), but rather discharges it from the chamber (210) to the outside through the air circulation line (272) and circulates it along the line, thereby ensuring that no air remains inside the chamber (210) and moves it, which further increases fluidity and increases mixing efficiency due to fluid circulation.

[0074] In addition, the present invention allows for forced air circulation by an air circulator (270) to be performed at various points during the manufacturing process, and in particular, the efficiency of the mixing reaction can be maximized by forcibly circulating air during the mixing reaction, such as when oxygen is introduced through an oxygen supply unit (220) or when distilled water is introduced through a distilled water supply unit (240).

[0075] Therefore, the present invention can improve the yield by increasing the reaction amount during nitric acid production for nitric acid recycling, and enables the acquisition of high-purity nitric acid through a concentration process.

[0076] Furthermore, in the present invention, the first reaction unit (200a) and the second reaction unit (200b) are not configured as separate reactors but are integrally provided in a single reactor, the chamber (210), so that the oxidation process and the nitrification reaction process can be performed separately within the chamber (210), thus eliminating the need to separately discharge or recover the fluid generated in each process, thereby providing significant structural advantages, and in particular, the continuity of each process can be easily maintained, which can increase productivity.

[0077] In order to recycle the nitric acid produced by the nitric acid production device described above, the system of the present invention may be provided with a re-transfer line (213) connected from the chamber (210) to the raw material reactor (100) and a re-transfer pump (214) connected to the re-transfer line (213), and the nitric acid produced in the nitric acid production reactor (200) can be transferred to the raw material reactor (100) by the operation of the re-transfer pump (214).

[0078] Meanwhile, referring again to FIG. 1, the nitric acid recycling device of the present invention is a device including the aforementioned nitric acid manufacturing device, comprising a raw material reaction tank for inducing an oxidation reaction by introducing nitric acid into a raw material, and a nitric acid production reaction tank connected to the raw material reaction tank for producing nitric acid by reacting nitrogen oxides generated in the raw material reaction tank. Here, the nitric acid production reaction tank includes a re-transfer means for transferring the produced nitric acid back to the raw material reaction tank.

[0079] In addition, although not illustrated in the drawings, the nitric acid production apparatus or nitric acid recycling apparatus of the present invention may further comprise an inspection device (not illustrated) for inspecting nitrogen oxide (NOx) gas. Such an inspection device is configured to detect nitrogen oxide (NOx) generated through the nitric acid reaction of biomass raw materials. x The composition ratio of the gas can be easily analyzed.

[0080] In one embodiment, the inspection device may be a sample collection device or configured in various other forms, and may be connected to the chamber of each reactor or installed at a predetermined location. Such an inspection device enables the determination of the components of nitrogen oxide gas or whether byproducts other than nitrogen oxide are present.

[0081] For example, since the amount of nitric acid produced may vary depending on control variables based on the amount of gas components, the gas is inspected using an inspection device, and reaction conditions are improved based on the presence of gas components and by-products, thereby enabling the appropriate production of nitric acid by changing each condition of the system.

[0082] Meanwhile, since the N2O gas generated during the production of glucaric acid according to the present invention requires a relatively high temperature (800 to 1000°C or higher), it is difficult to process it using the first reaction unit and the second reaction unit operating within a temperature range not exceeding 100°C. Therefore, it is desirable to allow the residual gas to be discharged through a separate recovery line (not shown) and then processed.

[0083] FIG. 2 schematically illustrates a nitric acid manufacturing apparatus according to another embodiment of the present invention. The nitric acid manufacturing apparatus according to this embodiment differs from the previously described embodiment in that it further includes a pretreatment oxidation unit (280'). That is, the nitric acid manufacturing apparatus (200') according to the second embodiment of the present invention is configured identically to the nitric acid manufacturing apparatus (200) according to the first embodiment, except for the configuration of the pretreatment oxidation unit (280'). Therefore, a detailed description of the configuration identical to the nitric acid manufacturing apparatus according to the first embodiment of the present invention is omitted below.

[0084] The nitric acid manufacturing apparatus (200') according to the second embodiment of the present invention may further include a pretreatment oxidation unit (280').

[0085] The pretreatment oxidation unit (280') is installed between the raw material reactor (100') and the nitric acid generating reactor (200') to perform a separate pretreatment oxidation operation before the oxidation reaction by the first reaction unit.

[0086] The pretreatment oxidation unit (280') can be implemented as a condenser. In this case, the condenser can be composed of a condenser or a heat exchanger and can be connected to an oxygen supply unit (220'). The pretreatment oxidation unit (280') can perform the same oxidation reaction as the first reaction unit by the oxygen supply unit (220') by introducing oxygen, and since it includes a heat exchanger, it can perform a cooling action on the nitrogen dioxide formed into a high-temperature substance by the oxidation reaction.

[0087] Accordingly, the present invention can perform the oxidation process of nitrogen oxides in two stages, and by first inducing an oxidation reaction in the pretreatment oxidation unit (280') and subsequently inducing an oxidation reaction through the first reaction unit for nitrogen oxides that did not participate in the reaction, the conversion rate to nitrogen dioxide can be further improved.

[0088] According to the nitric acid production apparatus of each embodiment of the present invention as described above, nitric acid is generated from nitrogen oxides, enabling the treatment of nitrogen oxides and the simultaneous recycling of nitric acid.

[0089] Hereinafter, a method for producing gluconic acid using the aforementioned nitric acid production device or nitric acid recycling device will be described.

[0090] As illustrated in FIG. 3, the method for producing glucaric acid according to the present invention comprises the step (S110) of producing glucaric acid from glucose, and nitrogen oxide (NO₂) generated as a byproduct during the glucose oxidation reaction. x It may include a step (S200) of recovering ) and recycling nitric acid from the recovered nitrogen oxide. The step (S200) of recycling nitric acid may include a method for producing nitric acid using the aforementioned nitric acid manufacturing apparatus.

[0091] At this time, when glucaric acid is produced, D-Gluconic acid, D-Gluconic acid, and D-Guluronic acid are generated by the mixing of D-Glucose and HNO3, and NOx (NO, NO2, N2O4) is generated as a byproduct.

[0092] In addition, the starting materials used in the present invention include Hydrol (glucose), HNO3, and NaNO2, the gas includes O2 and N2, and the additives may include HCl, KOH, and H2O.

[0093] First, the step (S110) of producing glucaric acid from glucose is to produce glucaric acid from glucose used as a raw material as shown in reaction scheme 1 below. The glucose used here may preferably be glucose derived from terrestrial plant resources as biomass, but is not limited thereto and may use glucose commonly used in the industry.

[0094] (Reaction Equation 1)

[0095]

[0096] Specifically, the glucaric acid production step (S110) can be performed by introducing glucose, which is a raw material, into a raw material reactor (100), and by introducing nitric acid to mix and react with the glucose.

[0097] At this time, in the raw material reactor (100), nitrogen oxide is produced as a byproduct along with glutaric acid as shown in reaction equation 2 below.

[0098] (Reaction Equation 2)

[0099]

[0100] The present invention can recover nitrogen oxides generated during the production of glucaric acid and regenerate and recycle them into nitric acid.

[0101] Accordingly, the step (S200) of recycling nitric acid from nitrogen oxides includes a method for producing nitric acid, and includes a step (S201) of recovering nitrogen oxides and transferring them to a chamber (210), an oxidation step (S210) of producing nitrogen dioxide by mixing and reacting nitric oxide and oxygen inside the chamber (210), and a nitrification step (S220) of producing nitric acid by mixing and reacting nitrogen dioxide and water inside the chamber (220). Subsequently, a step (S310) of transferring the generated nitric acid back to a raw material reactor (100) for recycling is performed.

[0102] Specifically, the oxidation step (S210) involves introducing oxygen into the interior of the chamber (210) to induce an oxidation reaction through a mixed reaction of nitric oxide and oxygen, thereby generating nitrogen dioxide. In this way, the S210 step induces an oxidation reaction of the internal gas, and nitrogen oxide (NO₂) x In particular, nitrogen dioxide (NO2) is produced through a mixed reaction of oxygen (O2) with nitric oxide (NO).

[0103] Subsequently, a step (S211) of cooling the chamber (210) may be performed. In step S211, the chamber (210) may be cooled to a temperature in the range of -20°C to 25°C by a cooling means (230). Accordingly, in step S211, the nitrogen oxide gas is cooled by the cooling means (230), thereby reducing the reactivity of the nitrogen oxide gas. At this time, the chamber (210) is cooled by a cooling coil or a cooling jacket.

[0104] In one embodiment, in step S211, nitrogen dioxide generated through the oxidation reaction and existing nitrogen dioxide are liquefied by the cooling action so that they can exist in a liquid state, thereby allowing reactivity to be controlled.

[0105] The nitrogen dioxide generated in this way is mixed and reacted with water in the nitrification step (S220) to produce nitric acid.

[0106] In one embodiment, the nitrification step (S220) may include a distilled water input step (S221) and a chamber heating step (S222).

[0107] In the distilled water injection step (S221), distilled water is introduced into the interior of the chamber (210) by the distilled water supply device (240), and a nitrification reaction can be induced through mixing with distilled water to produce nitric acid. That is, the distilled water supply pump (241) introduces distilled water stored in the distilled water tank (243) into the interior of the chamber (210) through the distilled water supply pipe (242) via a nozzle, and at this time, the nozzle installed in the chamber (210) sprays distilled water into the interior to allow the nitrification reaction process by nitrogen dioxide and water to be performed.

[0108] Here, in the distilled water injection step (S221), steam is injected into the interior of the chamber (210) by the distilled water supply (240) to carry out the initial reaction. Then, bubbles are formed by the supplied distilled water to induce close contact between the nitrogen dioxide and the distilled water. Subsequently, a scrubbing action can be performed to dissolve and remove the unreacted nitrogen dioxide in water, while simultaneously inducing an additional reaction with H2O to form nitric acid.

[0109] Additionally, the distilled water injection step (S221) may further include at least one of the steps of adjusting the installation angle of the nozzle that sprays distilled water into the chamber (210) (S221a), controlling the amount of spray from the nozzle (S221b), and controlling the size of the sprayed fine particles by adjusting the hole size of the nozzle (S221c), and the reaction efficiency can be increased by maximizing the surface area of ​​the distilled water through the control of the nozzle.

[0110] In one embodiment, the distilled water injection step (S221) may include a steam injection step (S221a), a bubbling step (S221b), and a scrubbing step (S221c).

[0111] In the chamber heating step (S222), the chamber (210) can be heated by a heating means (250). At this time, the chamber (210) is heated by the heating means (250) to a temperature in the range of 30°C to 150°C, and the residual H2O remaining inside the chamber (210) is heated, and the heated residue can be discharged to the outside of the chamber (210). That is, the chamber heating step (S222) can separate nitric acid and water by a distillation method while simultaneously rapidly evaporating and removing the water. This allows concentrated nitric acid to be obtained.

[0112] In one embodiment, a pressure reduction step (S223) for lowering the internal pressure of the chamber (210) may be performed after the chamber heating step (S222).

[0113] In the depressurization step (S223), the pressure of the chamber (210) is lowered to a low pressure by the depressurization means (260), thereby allowing the boiling point of the remaining H2O to be relatively lowered. That is, in the depressurization step (S223), even if the chamber (210) is heated to an appropriate temperature range in the chamber heating step (S222), the remaining H2O can be easily heated, and nitric acid can be efficiently separated by depressurization distillation, and the amount of water can be reduced to obtain highly concentrated nitric acid.

[0114] In this way, by performing the heating step (S222) and the vacuum reduction step (S223), highly concentrated nitric acid can be obtained by performing distillation and vacuum distillation processes within a single chamber (210). Although these heating step (S222) and vacuum reduction step (S223) have been described as separate processes, they may also be performed as a single nitric acid concentration step in which these processes are integrated.

[0115] In one embodiment, according to the present invention, an air circulation step (S230) may be performed before and after the oxidation step (S210) and the nitrification step (S220). That is, the air circulation step (S230) is performed by discharging the internal air of the chamber (210) to the outside of the chamber (210) via a circulation line and recirculating it.

[0116] The air circulation step (S230) can induce air circulation by discharging air inside the chamber (210) through the air circulation line (272) via the air circulator (270) to the outside of the chamber (210) while simultaneously recirculating it. At this time, the fluidity of the gas inside the chamber (210) can be increased to enhance the mixing reaction effect.

[0117] In particular, when the air circulation step (S230) is performed together with the oxidation step (S210) in which oxygen is supplied through the oxygen supply unit (220) or the distilled water supply step (S222) in which distilled water is introduced through the distilled water supply unit (240), the efficiency of the mixing reaction can be further maximized by forcibly circulating air during the mixing reaction.

[0118] Accordingly, the nitric acid recycling method and the method for producing gluconic acid using the same according to the present invention can improve the yield by increasing the reaction amount when generating nitric acid for nitric acid recycling, and can obtain high-purity nitric acid through a concentration process.

[0119] Meanwhile, the process of generating nitric acid from nitrogen oxides is illustrated in Reaction Scheme 3 below. First, the nitric oxide contained in the nitrogen oxides is generated as nitrogen dioxide through a mixing reaction with oxygen via an oxidation step (S210), and the generated nitrogen dioxide can be obtained as nitric acid by mixing with distilled water via a nitrification step (S220). Then, the nitrogen dioxide is converted into N2O4 via a cooling step (S211) and can be obtained as nitric acid by mixing with distilled water via a nitrification step (S220). In addition, the nitrogen dioxide existing as N2O4 in the nitrogen oxides can also be obtained as nitric acid by mixing with distilled water via a nitrification step (S220).

[0120] (Reaction Equation 3)

[0121]

[0122] Afterward, the final nitric acid produced through the nitrification step (S220) is transferred back to the raw material reactor (100) for recycling (S310). At this time, the nitric acid can be transferred to the raw material reactor (100) after pH analysis.

[0123] Ultimately, the present invention comprises a first step of mixing raw materials and nitric acid in a main reactor, a second step of recovering the nitrogen oxide generated in the first step to an auxiliary reactor, a third step of oxidizing and cooling the recovered nitrogen oxide, a fourth step of mixing water with the nitrogen oxide converted to a liquid state by cooling, a fifth step of heating the mixed mixture to produce highly concentrated nitric acid, and a sixth step of transferring the produced nitric acid to the main reactor for recycling.

[0124] As described above, the method for producing glucaric acid including a nitric acid recycling device according to the present invention can produce nitric acid from nitrogen oxides generated during the production of glucaric acid, thereby allowing for the treatment of nitrogen oxides and the recycling of nitric acid introduced along with the raw materials. Accordingly, the present invention has the advantage of reducing exhaust gas emitted to the outside and minimizing manufacturing costs through nitric acid recycling.

[0125] Table 1 below shows the analysis values ​​for each composition of nitrogen oxides.

[0126] CompoundN2ONONO2 / N2O4N2O3N2O5Oxidation state+1+2+4 / +4+3+5T Cr , ℃36.41-93157.85P Cr , MPa7.2456.48510.132Q Cr , kg / ㎥452520550mp, ℃-90.86-163.65-11.2-100.732.4 * bp,℃-88.48-151.7721.15-40to+3Specific heatc p , kJ kg -1 K -1 0.8790.9961.3260.8620.778Standard enthalpy of formation△H 0 F,kJ / kg1864.1903007.684721.1991101.435104.589Heat of vaporization atbp, kJ / kg376.07459.031414.257517.416Density, kg / ㎥Gas (0℃, 101.3 kPa)1.97751.34023.4(20℃)1.447(2℃)2.05(solid)Liquid (20℃, 101.3 kPa)7931446.8Dynamic viscosity, mPa·sGas (25℃, 101.3 kPa)14.87419.18412.838Thermal conductivity, Wm -1 K -1 Gas (25℃, 101.3 kPa)0.017180.025730.1124Liquid (20℃, 101.3 kPa)0.1336 * Sublimation Point.

[0127]

[0128] The foregoing description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are for illustrative purposes only and are not intended to limit the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments.

[0129] (Explanation of symbols)

[0130] 100, 100': Raw material reactor 200, 200': Nitric acid production reactor

[0131] 210, 210': Chamber 220, 220': Oxygen supply

[0132] 230, 230': Cooling means 240, 240': Distilled water supply

[0133] 250, 250': Heating means 260, 260': Pressure reducing means

[0134] 270, 270': Air circulator 280': Pretreatment oxidizer

Claims

1. A first reaction unit for generating nitrogen dioxide from a gas containing nitrogen oxides introduced into the interior of a chamber; and A nitric acid production apparatus comprising a second reaction unit provided in the chamber together with the first reaction unit and generating nitric acid from the dilute element.

2. In Claim 1, A nitric acid manufacturing apparatus further comprising an air circulation unit connected to the chamber and discharging the gas to the outside of the chamber and recirculating it.

3. In claim 1, the first reaction part is, It includes an oxygen supply connected to the above chamber, A nitric acid production apparatus characterized by inducing an oxidation reaction by oxygen with respect to the above-mentioned nitrogen oxide gas to generate nitrogen dioxide.

4. In claim 3, the first reaction part is, It further includes a cooling means for cooling the above chamber, A nitric acid manufacturing apparatus characterized by cooling the chamber to a temperature of -20°C to 25°C by the above cooling means.

5. In claim 4, the cooling means is, A cooling coil installed inside the chamber; and A nitric acid production apparatus including a cooling jacket installed outside the chamber.

6. In claim 1, the second reaction part is, Includes a distilled water supply connected to the above chamber, A nitric acid production apparatus characterized by inducing a nitrification reaction with the above-mentioned nitrogen dioxide through mixing with distilled water to produce nitric acid.

7. In claim 6, the second reaction unit is, It further includes a heating means for heating the above chamber, A nitric acid manufacturing apparatus characterized by heating the chamber to a temperature of 30°C to 150°C by the heating means above.

8. In claim 7, the second reaction unit is, A nitric acid manufacturing apparatus further comprising a pressure reduction means for lowering the pressure of the chamber.

9. A method for obtaining nitric acid from nitrogen oxides, An oxidation step of producing nitrogen dioxide by mixing and reacting nitric oxide and oxygen inside the chamber; and A method for producing nitric acid comprising a nitrification step of mixing and reacting the nitrogen dioxide and water inside the chamber to produce nitric acid.

10. In Claim 9, A method for producing nitric acid, further comprising a circulation step of discharging the internal air of the chamber to the outside of the chamber via a circulation line and recirculating it.

11. In Claim 9, A method for producing nitric acid, further comprising the step of cooling the chamber after the oxidation step.

12. In claim 9, the nitrification step is, A step of introducing distilled water into the interior of the chamber; and A method for producing nitric acid comprising the step of heating the above chamber.

13. In claim 12, the step of adding distilled water is, A step of adjusting the installation angle of a nozzle that sprays distilled water into the interior of the chamber; A step of controlling the injection amount of the above nozzle; and A method for producing nitric acid, further comprising at least one step of controlling the size of the sprayed fine particles by adjusting the hole size of the nozzle.

14. In Claim 12, A method for producing nitric acid that further includes a depressurization step of lowering the internal pressure of the chamber after the chamber is heated.

15. A raw material reaction vessel that induces an oxidation reaction by adding nitric acid to the raw material; and A reaction system using a nitric acid recycling device comprising a nitric acid production reaction tank connected to the above raw material reaction tank and for reacting nitrogen oxides generated in the above raw material reaction tank to produce nitric acid.

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