Electronic-grade NMP (N-Methyl Pyrrolidone) dehydration device based on molecular sieve membrane

Abstract

The utility model relates to the technical field of chemical equipment, in particular to an electronic-grade NMP (N-Methyl Pyrrolidone) dehydration device based on a molecular sieve membrane, which comprises a dehydration tank, a dehydration component is arranged in the dehydration tank, a feed port, a discharge port and a waste port are respectively arranged on the dehydration tank, and the feed port and the discharge port are respectively matched with an inlet end and an outlet end of the dehydration component; the dehydration assembly comprises a molecular sieve permeation tube, and a heat preservation sleeve sleeves the outer side of the molecular sieve permeation tube; a negative pressure cavity is formed in the heat preservation sleeve and connected to the waste opening through a negative pressure pipeline. The vacuum unit is matched with the molecular sieve permeation tube, and a negative pressure environment is formed outside the molecular sieve permeation tube, so that the permeation efficiency is improved; three dehydration tanks which are connected in sequence are arranged, a superheater and a heat supplementing device are sequentially arranged in front of the dehydration tanks, the temperature of raw materials in the osmotic dehydration process is kept, and finally electronic-grade NMP with the water content smaller than 200 PPM is produced.

Description

TECHNICAL FIELD

[0001] The utility model relates to a chemical equipment technical field, specifically for a kind of electronic grade NMP dehydration device based on molecular sieve membrane. BACKGROUND

[0002] NMP (N-methyl pyrrolidone) is a high-boiling, environmentally friendly excellent solvent, with low viscosity, good chemical stability, good thermal stability, high polarity, low volatility, unlimited miscibility with water and many organic solvents and many other advantages, widely used in lithium ion battery, solar cell, insulating material, bulletproof aramid fiber, microelectronics, integrated circuit, medicine, petrochemical, polymer material and many other fields, is one of the best application effect, the highest environmental index, the most promising market of organic industrial solvent on the market.

[0003] Industrial grade NMP generated by the reaction of GBL (gamma-butyrolactone, Gamma-Butyrolactone) and monomethylamine contains metal ions and moisture, and needs to be gradually dehydrated and impurity ions removed to obtain standard electronic grade NMP; Because electronic grade NMP has strict requirements on moisture content, the existing NMP production process by rectification dehydration generally cannot meet the higher requirements of the semiconductor field for the moisture content of electronic grade NMP. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a kind of electronic grade NMP dehydration device based on molecular sieve membrane, which can further reduce the moisture content of finished product and improve the purity of finished product.

[0005] To achieve the above purpose, the utility model adopts the following technical scheme:

[0006] An electronic grade NMP dehydration device based on molecular sieve membrane includes a dehydration tank, a dehydration assembly is arranged in the dehydration tank, a feed inlet, a discharge outlet and a waste outlet are arranged on the dehydration tank, and the feed inlet and the discharge outlet are arranged in cooperation with the inlet end and the outlet end of the dehydration assembly respectively; The dehydration assembly includes a molecular sieve permeation tube, and a heat preservation sleeve is sleeved outside the molecular sieve permeation tube; A negative pressure cavity is arranged on the heat preservation sleeve, and the negative pressure cavity is connected to the waste outlet through a negative pressure pipeline.

[0007] Preferably, a plurality of molecular sieve permeation tubes are uniformly distributed in the heat preservation sleeve, and both ends of each molecular sieve permeation tube are connected to the feed inlet and the discharge outlet of the dehydration tank respectively.

[0008] Preferably, the internal space of the negative pressure cavity communicates with the internal space of the heat preservation sleeve, and the negative pressure cavity is fixedly arranged on the heat preservation sleeve at one end close to the discharge outlet.

[0009] Preferably, a molecular sieve membrane layer is arranged on the pipe wall of the molecular sieve permeation tube, and the molecular sieve membrane layer is filled with molecular sieve.

[0010] Preferably, three dehydration tanks are connected in series, and each two adjacent dehydration tanks are connected by a feeding pipe between the outlet and the inlet; the inlet of the first dehydration tank is connected with a superheater by a feeding pipe, and a heat compensator is arranged between each two adjacent dehydration tanks; the waste outlet of the three dehydration tanks is connected with a condenser by a feeding pipe, and the condenser is connected with a vacuum unit and a permeate pump respectively.

[0011] The present application has the following advantages:

[0012] The present application uses a molecular sieve permeation pipe as the core component of the permeation dehydration assembly, which can filter out water molecules in the gas-phase NMP to the outside of the pipe, while keeping the NMP in the pipe, so as to reduce the water content of the finished product and improve the purity of the NMP; the molecular sieve permeation pipe is arranged in the heat preservation sleeve, and the filtered water molecules enter the gap between the heat preservation sleeve and the molecular sieve permeation pipe, can enter the negative pressure cavity, and then be discharged from the waste outlet through the negative pressure pipeline; the waste outlet is connected with the condenser and the vacuum unit in sequence, and the vacuum unit can generate vacuum negative pressure in the negative pressure cavity, thereby greatly reducing the pressure inside the heat preservation sleeve, generating a large pressure difference between the inside and outside of the molecular sieve permeation pipe, and increasing the efficiency of permeation dehydration; and the filtered water molecules and other impurities can be condensed by the condenser and then discharged and collected by the permeate pump, which is convenient for waste management.

[0013] The present application uses a structure of three dehydration tanks as a group, a superheater is arranged before the first dehydration tank to heat the product to a temperature above 220 DEG C, and a heat compensator is arranged between each two dehydration tanks to maintain the temperature of the NMP product during the dehydration process, so that the product is maintained in a gas phase state; in the dehydration tank, a heat preservation sleeve is arranged to reduce the heat loss of the product during the dehydration process, and after triple filtration, the water content of the NMP finished product can be effectively reduced to below 200 ppm, so as to meet the requirements of electronic-grade NMP. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is the overall flow chart of the present application;

[0015] Figure 2 It is the internal structure schematic view of the dehydration tank of the present application;

[0016] Figure 3 It is the internal structure schematic view of the dehydration tank of the present application;

[0017] Figure 4 It is the dehydration assembly cross section schematic view of the present application.

[0018] In the figure: dehydration tank 1; inlet 2; outlet 3; waste outlet 4; heat preservation sleeve 5; permeation cavity 51; negative pressure cavity 6; negative pressure pipeline 7; molecular sieve permeation pipe 8; raw material cavity 81. Detailed Implementation

[0019] The following is a further explanation of the present invention in conjunction with specific embodiments, such as... Figure 1 As shown, this embodiment is an electronic-grade NMP dehydration device based on molecular sieve membrane, which includes three dehydration tanks 1 connected in sequence; a superheater is provided in front of the first dehydration tank 1, which can heat the gaseous NMP for subsequent dehydration treatment; a supplementary heater is provided between every two dehydration tanks 1, which is used to reheat the gaseous product after one dehydration to a certain temperature for the next dehydration treatment.

[0020] The structure of dehydration tank 1 is as follows Figure 2 As shown, the dehydration tank 1 has a feed inlet 2 at the bottom, a discharge outlet 3 at the top, and a waste outlet 4 on the side. Inside the dehydration tank 1, an insulation sleeve 5 is installed, coaxially with the dehydration tank 1, and connected to both the feed inlet 2 and the discharge outlet 3. Multiple molecular sieve permeation tubes 8 are fitted inside the insulation sleeve 5, such as... Figure 3 As shown, the molecular sieve permeation tubes 8 are evenly distributed inside the insulation sleeve 5, and their top and bottom ends are connected to the outlet 3 and the inlet 2 through a bowl-shaped connector.

[0021] like Figure 4 As shown, the molecular sieve permeation tube 8 has a hollow structure, and its tube wall is provided with a molecular sieve membrane layer. In this embodiment, the molecular sieve membrane layer is composed of zeolite molecular sieve. The internal space of the molecular sieve permeation tube 8 is the raw material chamber, through which gaseous NMP that needs to be permeated and dehydrated passes. The gap between the molecular sieve permeation tube 8 and the heat insulation sleeve 5 is the permeation chamber 51, and water molecules in the raw material will enter the permeation chamber 51 after passing through the molecular sieve permeation tube 8.

[0022] like Figure 2 As shown, a negative pressure chamber 6 is provided on the insulation sleeve 5, and the negative pressure chamber 6 is located at one end near the discharge port 3; the negative pressure chamber 6 has a hollow internal structure, and its internal cavity is connected to the permeation chamber 51; the negative pressure chamber 6 is connected to the waste port 4 through a negative pressure pipe 7, and further, as shown... Figure 1 As shown, the waste port 4 is connected to the condenser and the vacuum unit in sequence through the feed pipe; the vacuum unit can generate a vacuum environment, thereby reducing the pressure in the negative pressure chamber 6 connected to it, and thus reducing the pressure in the permeation chamber 51; since the pressure in the permeation chamber 51 is much smaller than the pressure in the raw material chamber 81, the permeation rate of the raw material in the raw material chamber 81 can be accelerated, thereby effectively increasing the dehydration efficiency of the raw material NMP.

[0023] The water molecules filtered out by the molecular sieve permeation tube 8 are sucked into the condenser under the action of the vacuum unit, and the condensation is completed in the condenser to form a permeate, which is pumped out by the permeate pump after preliminary collection for subsequent waste liquid treatment process; the NMP after the first dehydration tank 1 dehydration treatment will be heated again in the heat compensator and then enter the second dehydration tank 1 for the second dehydration; in this way, the raw material NMP treated by the three dehydration tanks 1 in turn will become finished product NMP with extremely low water content and be discharged for subsequent processing and use; in this embodiment, the industrial grade NMP generated by the reaction of GBL and monomethylamine is subjected to rectification dehydration, and then further dehydration is performed by using the dehydration device in this embodiment, and it is verified that the dehydrated NMP meets the requirements of electronic grade NMP.

[0024] The above is only a further explanation and description of the utility model combined with specific embodiments, and all the descriptions do not represent a limitation on the protection scope of the utility model. Any changes or alternative solutions that can be easily thought of by any person skilled in the art within the technical scope disclosed by the utility model should be covered within the protection scope of the utility model. Therefore, the protection scope of the utility model should be subject to the protection scope of the claims.

Claims

1. A molecular sieve membrane based electronic grade NMP dehydration unit comprising a dehydration tank, characterized in that: The dehydration tank is provided with a dehydration assembly, and the dehydration tank is respectively provided with a feeding port, a discharging port and a waste port.

2. The molecular sieve membrane based electronic grade NMP dehydration device of claim 1, wherein: The dehydration tank is provided with a dehydration assembly, and the dehydration tank is respectively provided with a feeding port, a discharging port and a waste port.

3. The molecular sieve membrane based electronic grade NMP dehydration device of claim 2, wherein: The dehydration tank is provided with a dehydration assembly, and the dehydration tank is respectively provided with a feeding port, a discharging port and a waste port.

4. The molecular sieve membrane based electronic grade NMP dehydration device of claim 1, wherein: The dehydration tank is provided with a dehydration assembly, and the dehydration tank is respectively provided with a feeding port, a discharging port and a waste port.

5. The molecular sieve membrane based electronic grade NMP dehydration device of claim 1, wherein: The dehydration tank is provided with a dehydration assembly, and the dehydration tank is respectively provided with a feeding port, a discharging port and a waste port.

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