Oxidation reaction kettle for preparing aromatic acid by oxidizing aryl methyl

Abstract

The utility model discloses an oxidation reaction kettle for preparing aromatic acid by oxidizing aryl methyl. The oxidation reaction kettle comprises a kettle body, a stirring system, a cooling coil, an oxygen inlet system and a safety system, the oxygen inlet system comprises an oxygen inlet device, a nitric oxide detector and a control system; the control system is composed of a transmitter, a comparator, a controller and an actuator which are sequentially connected through wires. The transmitter is connected with the nitric oxide detector, and the actuator is connected with the air inlet valve; the safety system comprises a safety valve and a rupture disk device. According to the oxidation reaction kettle disclosed by the utility model, oxygen is introduced into the oxidation reaction kettle through the oxygen inlet system, so that the generated by-product gas nitric oxide is oxidized into nitrogen dioxide, and the nitrogen dioxide reacts with water to generate nitric acid, so that the utilization rate of the nitric acid is increased, the material consumption is reduced, and the production cost is reduced; and safety risks such as unstable temperature and pressure caused by frequent exhaust of a reaction system are reduced.

Description

Technical Field

[0001] The utility model relates to an oxidation reactor for the preparation of aromatic acid by oxidation of arylmethyl. Background Art

[0002] Organic oxidation reactions have been widely used in chemical production. Through oxidation reactions, bulk organic intermediates and high-performance polymer monomers can be produced, for example, nitrotoluene is oxidized to produce nitrobenzoic acid, tetramethyl methoxide is oxidized to produce tetracarboxylic acid, etc. There are many oxidation processes, mainly reagent oxidation, electrochemical oxidation, air one-step oxidation, etc., among which nitric acid oxidation is a more common reagent oxidation method.

[0003] In a conventional nitric acid oxidation reaction system, nitric acid acts as an oxidant. While oxidizing other raw materials, nitric acid itself will be reduced to low-valent gas compounds such as nitric oxide. The continuous generation of such by-product gases will increase the pressure of the reaction system. Therefore, it is necessary to discharge such by-product gases from the reaction system in a timely manner during the reaction to maintain the pressure stability and safety of the reaction system.

[0004] In addition, the low-valent gaseous compounds discharged from the oxidation reaction system need to be recycled, which not only increases the cost of reaction facilities and daily operation, but also increases the risk of substandard nitrogen oxide emissions. In addition, during the emission process, the reaction gas will also take away part of the heat energy in the reaction system, increasing energy consumption. At the same time, the oxidation reaction is an exothermic reaction. To ensure that the reaction temperature is stable and controllable, the existing oxidation reactor is difficult to meet the requirements of precise temperature control under these special conditions. Utility Model Content

[0005] The purpose of the utility model is to solve the above-mentioned problems and provide an oxidation reactor for the preparation of aromatic acid by oxidizing arylmethyl.

[0006] The technical solution for achieving the purpose of the utility model is: an oxidation reaction kettle for preparing aromatic acids by oxidation of aromatic methyl groups, comprising a kettle body, a stirring system and a cooling coil; the kettle body comprises a kettle body and a jacket; the stirring system comprises a drive motor and a stirrer, the drive motor is fixedly mounted on the outer upper end of the kettle body, the stirrer is connected to the drive motor and is located inside the kettle body; the cooling coil is arranged inside the kettle body and located on the periphery of the stirrer.

[0007] Furthermore, the oxidation reactor for preparing aromatic acids by oxidation of aromatic methyl groups of the utility model also includes an oxygen intake system; the oxygen intake system includes an oxygen intake device, a nitric oxide detector and a control system; the oxygen intake device includes an oxygen pipe and an intake valve; the control system is composed of a transmitter, a comparator, a controller and an actuator connected in sequence by wires; the transmitter is connected to the nitric oxide detector, and the actuator is connected to the intake valve.

[0008] Further, a number of fine holes that penetrate the inner and outer parts are provided on the pipe wall of the oxygen pipe.

[0009] Furthermore, the oxidation reactor for preparing aromatic acids by oxidation of aromatic methyl groups of the utility model also includes a safety system; the safety system includes a safety valve and a bursting disc device fixedly installed in parallel on the upper end of the outer side of the reactor body; the bursting disc device is composed of an upper clamp, a lower clamp and a bursting membrane fixed between the upper clamp and the lower clamp.

[0010] The utility model has the positive effects:

[0011] (1) The oxidation reactor of the utility model not only utilizes nitric acid as an oxidant, but also introduces oxygen into the oxidation reactor through an oxygen intake system, thereby oxidizing the by-product gas nitric oxide into nitrogen dioxide, and the nitrogen dioxide reacts with water to generate nitric acid, which not only increases the utilization rate of nitric acid, reduces material consumption, and reduces production costs, but also reduces safety risks such as temperature and pressure instability caused by frequent exhaust of the reaction system.

[0012] (2) The oxygen intake system of the utility model monitors the content of nitric oxide in the oxidation reactor online through a nitric oxide detector, and is connected to the intake valve through a control system. If the content of nitric oxide in the oxidation reactor increases, the opening degree of the intake valve is increased, otherwise, the opening degree of the intake valve is reduced, thereby reducing the oxygen content in the reaction system to a minimum and ensuring the safety of the reaction.

[0013] (3) The oxidation reactor of the utility model further improves the overall safety of the oxidation reactor by installing a safety valve and a blasting disk device. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the structure of the oxidation reactor for the preparation of aromatic acid by arylmethyl oxidation of the present invention.

[0015] Figure 2 It is a connection relationship diagram of the oxygen intake system of the present invention.

[0016] Figure 3 It is a structural diagram of the oxygen pipe of the present invention.

[0017] Figure 4 It is a structural diagram of the bursting disk device of the present invention. DETAILED DESCRIPTION

[0018] (Example 1)

[0019] See also Figure 1 The oxidation reactor for the preparation of aromatic acid in this embodiment for aryl methyl oxidation includes a kettle body 1, a stirring system 2, a cooling coil 3, an oxygen intake system 4 and a safety system 5.

[0020] The kettle body 1 includes a kettle body 11 and a jacket 12. The kettle body 11 is made of 316L stainless steel. The kettle body 11 is provided with an inlet 11-1 and a discharge port 11-2. The jacket 12 is provided with a heat medium inlet 12-1 and a heat medium outlet 12-2.

[0021] The stirring system 2 includes a driving motor 21 and an agitator 22 , which is fixedly installed at the outer upper end of the kettle body 11 , and the stirring machine 22 is connected to the driving motor 21 and is located inside the kettle body 11 .

[0022] The cooling coil 3 is arranged inside the kettle body 11 and is located on the outer periphery of the agitator 22 . The cooling coil 3 is provided with a refrigerant inlet 3-1 and a refrigerant outlet 3-2 .

[0023] The oxygen intake system 4 includes an oxygen intake device 41 , a nitric oxide detector 42 , and a control system 43 , and an oxygen intake device 41 includes an oxygen pipe 41 - 1 and an intake valve 41 - 2 .

[0024] See also Figure 2 The control system 43 is composed of a transmitter 43-1, a comparator 43-2, a controller 43-3 and an actuator 43-4 which are connected in sequence through wires. The transmitter 43-1 is connected to the nitric oxide detector 42, and the actuator 43-4 is connected to the intake valve 41-2.

[0025] See also Figure 3 , a number of fine holes 41-11 penetrated through the inner and outer parts are provided on the pipe wall of the oxygen pipe 41-1 to evenly disperse the oxygen in the oxygen pipe 41-1 into the kettle body 11.

[0026] See also Figure 1 and Figure 4 The safety system 5 includes a safety valve 51 and a bursting disc device 52 fixedly installed in parallel at the upper end of the exterior of the kettle body 11. The bursting disc device 52 is composed of an upper clamp 52-1, a lower clamp 52-2, and a bursting membrane 52-3 fixed between the upper clamp 52-1 and the lower clamp 52-2.

Claims

1. An oxidation reaction kettle for preparing aromatic acids by oxidation of aromatic methyl groups, comprising a kettle body (1), a stirring system (2) and a cooling coil (3); the kettle body (1) comprises a kettle body (11) and a jacket (12); the stirring system (2) comprises a driving motor (21) and a stirrer (22), the driving motor (21) being fixedly mounted on the upper end of the outside of the kettle body (11), the stirrer (22) being connected to the driving motor (21) and being located inside the kettle body (11); the cooling coil (3) being arranged inside the kettle body (11) and being located on the periphery of the stirrer (22); Features: It also includes an oxygen intake system (4); the oxygen intake system (4) includes an oxygen intake device (41), a nitric oxide detector (42) and a control system (43); The oxygen intake device (41) comprises an oxygen pipe (41-1) and an intake valve (41-2); The control system (43) is composed of a transmitter (43-1), a comparator (43-2), a controller (43-3), and an actuator (43-4) which are connected in sequence via wires; the transmitter (43-1) is connected to the nitric oxide detector (42), and the actuator (43-4) is connected to the intake valve (41-2).

2. The oxidation reactor for preparing aromatic acid by oxidation of arylmethyl group according to claim 1, characterized in that: The wall of the oxygen tube (41-1) is provided with a plurality of fine holes (41-11) that penetrate inside and outside.

3. The oxidation reaction kettle for preparing aromatic acid by oxidation of arylmethyl group according to claim 1 or 2, characterized in that: Also includes security systems (5); The safety system (5) comprises a safety valve (51) and a bursting disc device (52) fixedly mounted in parallel on the upper end of the exterior of the kettle body (11); the bursting disc device (52) is composed of an upper clamp (52-1), a lower clamp (52-2), and a bursting membrane (52-3) fixed between the upper clamp (52-1) and the lower clamp (52-2).

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