A device for irradiating a dimethyldiallylammonium chloride solution and a decolorization method

Abstract

The present invention discloses an irradiation device and a decolorization method for dimethyldiallylammonium chloride solution, belonging to the technical field related to the storage of polymer monomers. In the present invention, the to-be-detected green dimethyldiallylammonium chloride is transferred into the reaction kettle body, and the motor is started to drive the stirring assembly to start working; the ultraviolet irradiation assembly is started for irradiation, and the stirring assembly is started. Under ultraviolet light, the complex is dissociated to regenerate ferrous ions and vinyl chloride. During the irradiation and stirring, sampling is carried out through the sampling port for observation; the sample is compared with the standard colorimetric card, and when the sample is clarified, the reaction is stopped, and the monomer is pumped into the monomer storage tank. This method solves the problem that it is difficult to handle the green dimethyldiallylammonium chloride, overcomes the subsequent desorption step required when using activated carbon to remove the green color in the traditional method, reduces the decolorization cost, and at the same time has the advantage of high single-batch processing efficiency.

Description

Technical Field

[0001] The present invention relates to the field related to the storage of polymer monomers, and specifically to an irradiation device and a decolorization method for dimethyldiallylammonium chloride solution. Background Art

[0002] Dimethyldiallylammonium chloride, with the chemical formula C8H 16 NCl, is an organic monomer with a relatively high positive charge density. Due to the presence of double bonds and cationic quaternary ammonium groups in the molecule, and its good water solubility, high efficiency and non-toxicity, it can be used to prepare a variety of high molecular compounds and copolymerize with many unsaturated monomers, and has a wide range of application fields.

[0003] Water-soluble dimethyldiallylammonium chloride is usually stored in the form of a solution. During the storage process, since the raw material allyl chloride often contains ferrous ions, the ferrous ions react with allyl chloride to form a green complex [Fe(H2O) m (3AC) n 2+ , this complex is dissolved in the dimethyldiallylammonium chloride solution and cannot be removed by conventional methods. Moreover, as the storage time lengthens, the color of the product will deepen. The existing decolorization methods are as follows: ① Pass N2 during the synthesis stage to remove the excess oxygen in the reactor to prevent the product from turning green after being oxidized by oxygen; ② Control the temperature during the reaction stage (not exceeding 30°C during the dropping stage and not exceeding 45°C during the heat preservation stage); ③ Decolorize the product with activated carbon. However, in the above methods, it is difficult to avoid the situation that trace amounts of ferrous ions cause the formation of complexes during the storage process, and the activated carbon cannot remove the complexes generated in the subsequent steps.

[0004] Therefore, there is a need for a low-cost and high single-batch processing efficiency decolorization method for dimethyldiallylammonium chloride solution. Summary of the Invention

[0005] To solve the existing technical problems, the present invention provides an irradiation device for dimethyldiallylammonium chloride solution, including a reaction kettle body. At least one ultraviolet irradiation component is provided inside the reaction kettle body. The ultraviolet irradiation component includes a lamp tube and a glass sleeve sleeved outside the lamp tube; the lower end of the reaction sleeve is connected to the first monomer output pipeline, and the lower end is connected to the second monomer output pipeline; a sampling port is also provided near the lower end of the reaction sleeve.

[0006] Preferably or optionally, at least one lower through port, at least one upper through port and a sampling port are provided at the bottom of the reaction kettle body. The lower through port is connected to the monomer temporary storage tank through a valve; the upper through port is connected to the monomer storage tank through a valve, and the sampling port is arranged at the lower part of the reaction kettle body.

[0007] Preferably or optionally, the wavelength of the lamp tube is 320 - 400 nm.​

[0008] Preferably or optionally, the dimethyldiallylammonium chloride solution irradiation device further includes a titanium skeleton fixed to the inner top of the tank. A flange interface is provided above the titanium skeleton. The titanium skeleton is sleeved outside the glass sleeve, and both ends of the titanium skeleton are sealed by a sealing gland head.

[0009] Preferably or optionally, it further includes a stirring assembly disposed inside the kettle body and connected to the motor at the upper end.

[0010] A method for decolorizing dimethyldiallylammonium chloride based on the irradiation device described in any one of the above, includes the following steps:

[0011] Step 1: Pump the dimethyldiallylammonium chloride monomer from the monomer temporary storage tank into the dimethyldiallylammonium chloride solution irradiation device;

[0012] Step 2: Turn on the ultraviolet lamp for irradiation, turn on the stirring assembly, and take samples through the sampling port for observation during the irradiation and stirring;

[0013] Step 3: Compare the sample with the standard colorimetric card. When the sample is clarified, stop the reaction and pump the monomer into the monomer storage tank.

[0014] Beneficial effects: The present invention provides a dimethyldiallylammonium chloride solution irradiation device for decolorizing dimethyldiallylammonium chloride solution. When preparing dimethyldiallylammonium chloride monomer, the residual ferrous ions in the system react with allyl chloride to form a complex: Fe 2+ +mH2O+3AC——→[Fe(H2O) m (3AC) n 2+ , under the ultraviolet light of the present invention, the complex undergoes dissociation to regenerate ferrous ions, water and vinyl chloride: Vinyl chloride reacts with the residual dimethylamine in the system to form dimethylallylamine and is stored in the product. Ferrous ions are oxidized to form ferric ions and are stored in the product: 2(CH3)NH+CH2=CHCH2Cl——→2(CH3)NCH2CH=CH2+HCl; The ferric ions and dimethylallylamine generated by this method are as low as the ppm (one in a million) level, and experiments prove that it has almost no impact on the polymerization reaction performance of the monomer. Therefore, no impurity removal treatment is required. This method solves the problem that dimethyldiallylammonium chloride has been difficult to handle when it turns green, overcomes the subsequent desorption steps required in the traditional method of using activated carbon to remove green color, reduces the decolorization cost, and has the advantage of high single-batch processing efficiency. Description of the Drawings

[0015] ​Figure 1 This is a schematic structural diagram of the device of the present invention.

[0016] Figure 2 This is a radial sectional view of the ultraviolet irradiation component of the present invention.

[0017] The reference numerals are: reaction kettle body 1, lower through port 1.1, upper through port 1.2, sampling port 1.3, ultraviolet irradiation component 2, lamp tube 2.1, glass sleeve 2.2, titanium skeleton 2.3, stirring component 3, motor 4. Specific embodiments

[0018] In order to better understand the above technical solutions, the above technical solutions will be described in detail below in conjunction with the accompanying drawings of the specification and specific embodiments.

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the mechanisms of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0020] The following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention claimed, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0021] It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0022] In the description of the embodiments of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationships in which the products of the invention are customarily placed during use, or the orientation or positional relationships commonly understood by those skilled in the art. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0023] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations. The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and cannot be used to limit the protection scope of the present invention.

[0024] The examples of the following embodiments are intended to explain the present invention and should not be construed as limiting the present invention. For those not specifying specific techniques and reaction conditions in the embodiments, the techniques or conditions described in the literature in the art or the product specifications can be followed. For reagents, instruments or equipment without indicating the manufacturers, they can all be obtained commercially.

[0025] There is currently a method for treating dimethyldiallylammonium chloride with an external ultraviolet lamp tube casing. From a technical perspective, there are the following disadvantages: a large number of devices are required. For the external type, at least two product storage tanks are required, resulting in a large floor area and high costs; the single-batch processing capacity is small. The volume of the tank is 60 m 3 , while the volume of the external ultraviolet irradiation component is 1 m 3 , and it takes 60 times to process a full tank, resulting in a too long processing time and low efficiency; a high demand for labor. This method always requires manual sampling and detection, with a high labor ratio and low economic benefits. If an operation error causes product polymerization, the treatment method is difficult. The polymerization of monomers in the pipeline blocks the pipeline and is difficult to handle; during the light irradiation process, the liquid is in a static state, with a certain risk of polymerization. Therefore, it is necessary to improve the current method for decolorizing dimethyldiallylammonium chloride solution.

[0026] Example 1

[0027] Referring to the attached Figure 1 , transfer the greenish dimethyldiallylammonium chloride to be tested into the reaction kettle body 1 through the upper through port 1.2, turn on the motor 4 to drive the stirring component 3 to start working, and turn on the ultraviolet irradiation component 2 with a wavelength of 360 nm. During this period, observe the color change of the product in the reaction kettle body 1 through the sampling port 1.3. When irradiated for 30 minutes, take a sample through the sampling port 1.3 to detect the product color. If it meets the standard, turn off the ultraviolet irradiation component 2 and the motor 4. The ultraviolet irradiation component includes a lamp tube 2.1, a glass sleeve 2.2 sleeved outside the lamp tube 2.1, and a hollow titanium skeleton 2.3 sleeved outside the glass sleeve 2.2 for protecting the internal lamp tube 2.1 and glass sleeve 2.2.

[0028] Example 2

[0029] Transfer the greenish dimethyldiallylammonium chloride to be tested into the reaction kettle body 1 through the upper through port 1.2. Start the motor 4 to drive the stirring assembly 3 to work. Turn on the ultraviolet irradiation assembly 2 with a wavelength of 320 nm. During this period, observe the color change of the product in the reaction kettle body 1 through the sampling port 1.3. When irradiated for 30 minutes, take a sample through the sampling port 1.3 to detect the color of the product. If the standard is met, turn off the ultraviolet irradiation assembly 2 and the motor 4. The ultraviolet irradiation assembly includes a lamp tube 2.1, a glass sleeve 2.2 sleeved outside the lamp tube 2.1, and a hollowed-out titanium skeleton 2.3 sleeved outside the glass sleeve 2.2, which is used to protect the internal lamp tube 2.1 and glass sleeve 2.2.

[0030] Example 3

[0031] Transfer the greenish dimethyldiallylammonium chloride to be tested into the reaction kettle body 1 through the upper through port 1.2. Start the motor 4 to drive the stirring assembly 3 to work. Turn on the ultraviolet irradiation assembly 2 with a wavelength of 380 nm. During this period, observe the color change of the product in the reaction kettle body 1 through the sampling port 1.3. When irradiated for 25 minutes, take a sample through the sampling port 1.3 to detect the color of the product. If the standard is met, turn off the ultraviolet irradiation assembly 2 and the motor 4. The ultraviolet irradiation assembly includes a lamp tube 2.1, a glass sleeve 2.2 sleeved outside the lamp tube 2.1, and a hollowed-out titanium skeleton 2.3 sleeved outside the glass sleeve 2.2, which is used to protect the internal lamp tube 2.1 and glass sleeve 2.2.

[0032] Example 4

[0033] Transfer the greenish dimethyldiallylammonium chloride to be tested into the reaction kettle body 1 through the upper through port 1.2. Start the motor 4 to drive the stirring assembly 3 to work. Turn on the ultraviolet irradiation assembly 2 with a wavelength of 360 nm. During this period, observe the color change of the product in the reaction kettle body 1 through the sampling port 1.3. When irradiated for 20 minutes, take a sample through the sampling port 1.3 to detect the color of the product. If the standard is met, turn off the ultraviolet irradiation assembly 2 and the motor 4. The ultraviolet irradiation assembly includes a lamp tube 2.1, a glass sleeve 2.2 sleeved outside the lamp tube 2.1, and a hollowed-out titanium skeleton 2.3 sleeved outside the glass sleeve 2.2, which is used to protect the internal lamp tube 2.1 and glass sleeve 2.2.

[0034] Example 5

[0035] Transfer the dimethyldiallylammonium chloride to be tested for greening into the reaction kettle body 1 through the upper through-port 1.2. Turn on the motor 4 to drive the stirring assembly 3 to start working. Turn on the ultraviolet irradiation assembly 2 with a wavelength of 320 nm. During this period, observe the color change of the product in the reaction kettle body 1 through the sampling port 1.3. When irradiated for 20 minutes, take a sample through the sampling port 1.3 to detect the color of the product. If it meets the standard, turn off the ultraviolet irradiation assembly 2 and the motor 4. The ultraviolet irradiation assembly includes a lamp tube 2.1, a glass sleeve 2.2 sleeved outside the lamp tube 2.1, and a hollow titanium skeleton 2.3 sleeved outside the glass sleeve 2.2, which is used to protect the internal lamp tube 2.1 and glass sleeve 2.2.

[0036] In this application, the decolorized monomers of Examples 1 to 5 are sampled through standard colorimetric tubes, and they are respectively filled into colorimetric tubes and compared with a colorimetric tube filled with a standard solution. When comparing, place the two colorimetric tubes in front of white paper with the same illumination level, and observe the color difference with the naked eye for comparison. The following Table 1 can be obtained

[0037] Table 1

[0038] As it is Example 1 Example 2 Example 3 Example 4 Example 5 Color 70# 10# 20# 10# 30# 10# Status Clear Clear Clear Clear Clear Clear

[0039] According to the results in the above table, it can be seen that when the wavelength of the ultraviolet lamp tube in the example is 360 nm and the irradiation time of the ultraviolet lamp tube is 30 minutes, the obtained color number is the lightest, which proves that the efficiency of removing green from dimethyldiallylammonium chloride is the highest, and at the same time, it will not cause the monomer to self-polymerize to produce gel. When the wavelength of the ultraviolet light is too high, the irradiation time of the ultraviolet lamp tube should be correspondingly reduced to prevent the monomer from being excited into monomer free radicals and causing self-polymerization due to too long irradiation time.

[0040] In addition, it should be noted that in the above specific embodiments, the various specific technical features described can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

Claims

1. A method for decolorizing dimethyldiallylammonium chloride, characterized in that, An irradiation device is adopted. The irradiation device includes: a reaction kettle body, at least one group of ultraviolet irradiation components are arranged inside the reaction kettle body, and the ultraviolet irradiation components include a lamp tube and a glass sleeve sleeved outside the lamp tube; a sampling port is also arranged near the lower end of the reaction kettle body; at least one lower through port, at least one upper through port and a sampling port are arranged at the bottom of the reaction kettle body, and the lower through port is connected to a monomer temporary storage tank through a valve; the upper through port is connected to a monomer storage tank through a valve, and the sampling port is arranged at the lower part of the reaction kettle body; a stirring component arranged inside the kettle body and connected to a motor at the upper end is also included; The method includes the following steps: Step 1: Pump the dimethyldiallylammonium chloride monomer from the monomer temporary storage tank into the dimethyldiallylammonium chloride solution irradiation device; Step 2: Turn on the ultraviolet lamp tube for irradiation, turn on the stirring component, and take samples and observe through the sampling port during the irradiation and stirring; Step 3: Compare the sample with a standard colorimetric tube. When the sample is clarified, stop the reaction and pump the monomer into the monomer storage tank.

2. The method for decolorizing dimethyldiallylammonium chloride according to claim 1, characterized in that, The wavelength of the lamp tube is 320-400 nm.

3. The method for decolorizing dimethyldiallylammonium chloride according to claim 1, characterized in that, The dimethyldiallylammonium chloride solution irradiation device further includes a hollowed-out titanium skeleton arranged outside the glass sleeve.

4. The method for decolorizing dimethyldiallylammonium chloride according to claim 3, characterized in that, A flange interface is arranged above the hollowed-out titanium skeleton.

5. The method for decolorizing dimethyldiallylammonium chloride according to claim 3, characterized in that, Both ends of the hollowed-out titanium skeleton are sealed through a sealed gland.

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