A continuous stripping crystallization method and device for tris(tribromophenoxy)triazine

Abstract

The present invention provides a continuous stripping crystallization method and device for tris(tribromophenoxy)triazine, and relates to the field of tris(tribromophenoxy)triazine. The continuous stripping crystallization method for tris(tribromophenoxy)triazine comprises the following steps: continuously preparing a micro-dispersed emulsion, and continuously stripping crystallizing. The continuous stripping crystallization method and device for tris(tribromophenoxy)triazine of the present invention can overcome the problems of residual product components in the crystallization solvent, residual solvent in the solid product, low crystallization efficiency, and poor environmental protection in the existing tris(tribromophenoxy)triazine crystallization process; while effectively realizing the continuous crystallization of tris(tribromophenoxy)triazine, it can avoid the agglomeration and agglomeration problems of tris(tribromophenoxy)triazine solid particles, and obtain a tris(tribromophenoxy)triazine product with uniform particle size distribution.

Description

Technical Field

[0001] The invention relates to the field of tris(tribromophenoxy)triazine, in particular to a continuous stripping crystallization method and device for tris(tribromophenoxy)triazine. Background Art

[0002] At present, in the preparation process of tris(tribromophenoxy)triazine, the prior art has proposed a variety of solutions for how to extract a solid product from the prepared tris(tribromophenoxy)triazine crude solution. For example, Chinese patents CN103275025B and CN102414183A all propose a precipitation method of cooling crystallization to extract tris(tribromophenoxy)triazine from the crude solution; and Chinese patents CN102344420A and CN102838554A all propose a precipitation method of water azeotropic crystallization to extract tris(tribromophenoxy)triazine from the solution.

[0003] For the cooling crystallization method of tris (tribromophenoxy) triazine, taking Chinese patent CN103275025B as an example, it provides an optimized bromotriazine production method, specifically, the crude tris (tribromophenoxy) triazine liquid after washing is transferred to a heating kettle, and vacuum filtration is performed under the state of heating and dissolution, and finally transferred to a distillation kettle for stirring crystallization, drying, and obtaining a tris (tribromophenoxy) triazine product. Although the cooling crystallization method can obtain a solid product with higher purity, there are product components remaining in the crystallization solvent, and there are solvent residues in the solid product, the crystallization efficiency is low, the post-processing is complicated, and the environmental protection is poor.

[0004] For the water azeotropic crystallization method of tris(tribromophenoxy)triazine, taking Chinese patent CN102344420A as an example, it provides a preparation method of tris(tribromophenoxy)triazine, specifically, adding an organic liquid (i.e., the prepared tris(tribromophenoxy)triazine solution) into the crystallization kettle through the feed port of the crystallization kettle, and then adding an appropriate amount of deionized water or distilled water into the crystallization kettle through a water metering tank, heating and distilling, separating the fractions through a condenser and a water separator, reflux water to the crystallization kettle, and collecting the organic solvent. The method is applied in a set manner; when a fraction comes out, water is added at the same time, and the speed of water addition is equal to the speed of distillation of the organic solvent, so as to keep the total volume of the material in the crystallization kettle unchanged; after all the organic solvents are evaporated, the distillation is continued for 30 minutes; then the temperature of the material in the crystallization kettle is reduced to below 40°C, the material is discharged and centrifuged to obtain fine particles of solid tris(tribromophenoxy)triazine wet product; the tris(tribromophenoxy)triazine wet product is dried to obtain a granular solid tris(tribromophenoxy)triazine product with a particle size of 0.8-2.0mm. Although the technical solution of this patent adopts water azeotropic crystallization to replace the existing cooling crystallization and solvent extraction crystallization, it can improve the crystallization state to a certain extent, but there are still product components residual in its solvent, the environmental protection is poor, and the crystallization efficiency needs to be further improved.

[0005] In addition to the above-mentioned defects, the above-mentioned tris(tribromophenoxy)triazine crystallization treatment method has the following more important problem: each existing tris(tribromophenoxy)triazine crystallization method is an intermittent solid-liquid crystallization separation process, and the treatment process is not easy to control, which seriously limits the production efficiency of tris(tribromophenoxy)triazine, has high production costs, and cannot achieve continuous tris(tribromophenoxy)triazine crystallization treatment.

[0006] Furthermore, the inventors discovered during the research and development of continuous crystallization of tris(tribromophenoxy)triazine that in the continuous crystallization of a crude solution of tris(tribromophenoxy)triazine, there were problems of uneven distribution of product particle size, as well as agglomeration and caking of product particles; it was not possible to effectively achieve continuous crystallization of tris(tribromophenoxy)triazine while avoiding the agglomeration and agglomeration of tris(tribromophenoxy)triazine solid particles to obtain a tris(tribromophenoxy)triazine product with uniform particle size distribution. Summary of the invention

[0007] In order to solve the technical problems existing in the prior art, the present invention provides a continuous steam stripping crystallization method and device for tris(tribromophenoxy)triazine, which overcomes the problems of residual product components in the crystallization solvent, residual solvent in the solid product, low crystallization efficiency and poor environmental protection in the prior art tris(tribromophenoxy)triazine crystallization process; while effectively realizing the continuous crystallization of tris(tribromophenoxy)triazine, the agglomeration and agglomeration problems of tris(tribromophenoxy)triazine solid particles can be avoided, and a tris(tribromophenoxy)triazine product with uniform particle size distribution can be obtained.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0009] A continuous steam stripping crystallization method for tris(tribromophenoxy)triazine comprises the following steps: continuously preparing a micro-dispersed emulsion, and continuously stripping crystallizing;

[0010] The method for continuously preparing a micro-dispersed emulsion comprises: adding a dichloromethane solution of tris(tribromophenoxy)triazine and hot water into a crystallization kettle in advance; simultaneously and continuously feeding the dichloromethane solution of tris(tribromophenoxy)triazine and hot water into a micro-dispersed extractor to obtain a micro-dispersed emulsion, and continuously discharging the emulsion into the crystallization kettle;

[0011] In the continuous preparation of the microdisperse emulsion, the dichloromethane solution of tris(tribromophenoxy)triazine continuously fed into the microdisperse extractor has a temperature of 20-40°C and the hot water has a temperature of 60-95°C;

[0012] The continuous steam stripping crystallization method comprises the following steps: the crystallization kettle continuously receives the micro-dispersed emulsion from the micro-dispersed extractor and maintains the temperature of the crystallization kettle at 60-95° C.; at the same time, under the action of a material transfer pump, a part of the mixed crystallization material in the crystallization kettle is refluxed to the crystallization kettle, and the other part is taken out to a centrifuge for centrifugation, and then solid-liquid separation is performed to obtain tris(tribromophenoxy)triazine solid crystal particles.

[0013] Preferably, in the continuously prepared microdispersed emulsion, the content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 10-50wt%.

[0014] Preferably, in the continuous preparation of the micro-dispersed emulsion, the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance to the crystallization kettle is equal to the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor.

[0015] Preferably, in the continuous preparation of the micro-dispersed emulsion, the mass ratio of the hot water added in advance to the dichloromethane solution of tris(tribromophenoxy)triazine in the crystallization kettle is 1-10:1; the mass ratio of the hot water continuously passed into the micro-dispersed extractor to the dichloromethane solution of tris(tribromophenoxy)triazine is 1-10:1.

[0016] Preferably, in the continuous stripping crystallization, the residence time of the micro-dispersed emulsion in the crystallization kettle is 30-60 min.

[0017] Preferably, in the continuous stripping crystallization, a portion of the mixed crystal material in the crystallization kettle is refluxed to the crystallization kettle under the action of a material transfer pump, and the other portion is extracted to a centrifuge with a reflux ratio of 1-5:1.

[0018] Furthermore, in the continuous steam stripping crystallization, the solvent dichloromethane of the dichloromethane solution of tris(tribromophenoxy)triazine that is volatilized by heat is continuously collected and recovered after condensation;

[0019] The liquid recovered from centrifugation and solid-liquid separation in the centrifuge is heated to obtain hot water, which is then recycled and fed to the micro-dispersion extractor.

[0020] Preferably, the absolute dry mass of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine continuously fed to the micro-disperse extractor is controlled to be equal to the absolute dry mass of tris(tribromophenoxy)triazine in the mixed crystal material extracted into the centrifuge.

[0021] A continuous steam stripping crystallization device for tris(tribromophenoxy)triazine for realizing the above method comprises: a micro-dispersion extractor, a crystallization kettle, a material transfer pump, and a condenser;

[0022] The discharge port of the micro-dispersed extractor is connected to the feed port of the crystallization kettle, the bottom discharge port of the crystallization kettle is connected to the feed port pipeline of the transfer pump, the discharge pipeline of the transfer pump is connected to the circulation pipeline and the centrifuge feed pipeline; the circulation pipeline is connected in parallel with the centrifuge feed pipeline;

[0023] The light component outlet at the top of the crystallization kettle is connected to the feed inlet pipeline of the condenser.

[0024] The micro-dispersed extractor is used to continuously receive and process the dichloromethane solution and hot water of tris(tribromophenoxy)triazine to obtain a micro-dispersed emulsion;

[0025] The micro-dispersion extractor is composed of a microporous disperser and an extractor;

[0026] The microporous disperser contains 15-20 organic phase dispersion sieve holes with a diameter of 0.5-2 mm, and at least one T-shaped or Y-shaped oil-water intersection channel structure with a hydraulic diameter of 3-5 mm;

[0027] The inner wall of the extractor is evenly provided with symmetrically distributed mushroom-shaped protrusions, and the height of the mushroom-shaped protrusions is 1 / 5-2 / 5 of the inner diameter of the extractor.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) The continuous stripping crystallization method and device of tris(tribromophenoxy)triazine of the present invention comprises the following steps: continuously feeding a dichloromethane solution of tris(tribromophenoxy)triazine at a specific temperature and hot water into a micro-dispersed extractor, and obtaining a micro-dispersed emulsion after being treated by a microporous disperser and an extractor; then, the micro-dispersed emulsion is continuously fed into a crystallization kettle, and under specific crystallization temperature conditions, continuous stripping crystallization is performed by controlling the residence time of the micro-dispersed emulsion and the reflux ratio of the mixed crystallization material in the crystallization kettle; the mixed crystallization material taken out of the centrifuge is centrifuged and solid-liquid separated to obtain tris(tribromophenoxy)triazine. The invention discloses a method for preparing triazine solid crystal particles (wet material), and the liquid obtained by centrifugation and solid-liquid separation can be reused as hot water in the step of continuously preparing a micro-dispersed emulsion; the aforementioned technical means cooperate with each other and work synergistically, and can solve the problems of residual product components in the crystallization solvent during the crystallization of tris(tribromophenoxy)triazine, residual solvent in the solid product, low crystallization efficiency and poor environmental protection; the invention can effectively realize the continuous crystallization of tris(tribromophenoxy)triazine while avoiding the problems of agglomeration and caking of tris(tribromophenoxy)triazine solid particles, and obtain a tris(tribromophenoxy)triazine product with uniform particle size distribution.

[0030] (2) The continuous steam stripping crystallization method of tris(tribromophenoxy)triazine of the present invention, the tris(tribromophenoxy)triazine solid crystalline particles obtained by crystallization have regular shape and uniform particle size, no agglomeration and caking, and the residual amount of solvent (dichloromethane) in the tris(tribromophenoxy)triazine solid crystalline particles is 0g / kg; the tris(tribromophenoxy)triazine solid crystalline particles obtained by crystallization are dried to remove moisture, and the tris(tribromophenoxy)triazine solid product can be obtained.

[0031] (3) The continuous steam stripping crystallization method of tris(tribromophenoxy)triazine of the present invention can effectively realize the continuous crystallization of tris(tribromophenoxy)triazine while effectively recovering the solvent (dichloromethane) of the dichloromethane solution of tris(tribromophenoxy)triazine volatilized by heat during the continuous steam stripping crystallization; the water recovered from the centrifuge and solid-liquid separation can also be reused in the continuous preparation step of the micro-dispersed emulsion. The continuous production process does not generate sewage, and the subsequent post-treatment is highly environmentally friendly.

[0032] (4) The continuous steam stripping crystallization method of tris(tribromophenoxy)triazine of the present invention is simple in process, easy to operate, and suitable for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the device for continuous steam stripping crystallization of tris(tribromophenoxy)triazine according to Example 1 of the present invention.

[0034] In the figure, 1-hot water supply pipeline; 2-liquid feed pipeline; 3-micro-dispersion extractor; 4-crystallization kettle; 5-feed transfer pump; 6-circulation pipeline; 7-centrifuge feed pipeline; 8-condenser; 9-emulsion delivery pipeline. DETAILED DESCRIPTION

[0035] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation methods of the present invention are now described.

[0036] The present invention provides a device for continuous stripping crystallization of tris(tribromophenoxy)triazine, comprising: a micro-dispersed extractor 3, a crystallization kettle 4, a material transfer pump 5, and a condenser 8.

[0037] The micro-dispersed extractor 3 is fixedly connected with a hot water supply pipeline 1, a liquid feed pipeline 2, and an emulsion delivery pipeline 9. The hot water supply pipeline 1 is connected to the main inlet of the micro-dispersed extractor 3 so as to continuously supply hot water to the micro-dispersed extractor 3; the liquid feed pipeline 2 is connected to the side inlet of the micro-dispersed extractor 3 so as to continuously feed a dichloromethane solution of tris(tribromophenoxy)triazine to the micro-dispersed extractor 3.

[0038] The micro-dispersion extractor 3 is used to perform micro-dispersion extraction on a dichloromethane solution of tris(tribromophenoxy)triazine and hot water to obtain a micro-dispersion emulsion; the micro-dispersion extractor 3 is composed of a microporous disperser and an extractor, wherein the microporous disperser contains at least one organic phase dispersion sieve hole with a diameter of 0.5-5 mm, and at least one T-shaped or Y-shaped oil-water intersection channel structure with a hydraulic diameter of 0.2-5 mm; preferably, the microporous disperser contains 15-20 sieve holes with a diameter of 0.5-2 mm. The invention discloses an organic phase dispersion sieve hole and at least one T-shaped or Y-shaped oil-water intersection channel structure with a hydraulic diameter of 3-5 mm; the inner wall of the extractor is evenly provided with symmetrically distributed mushroom-shaped protrusions, and the height of the mushroom-shaped protrusions is 1 / 5-2 / 5 of the inner diameter of the extractor; the function of the extractor is, on the one hand, to extract part of tri(tribromophenoxy)triazine in the hot water extraction solution, and on the other hand, to improve the mixing uniformity of hot water and dichloromethane solution of tri(tribromophenoxy)triazine in the micro-dispersed emulsion.

[0039] One end of the emulsion delivery pipeline 9 is connected to the discharge port of the micro-dispersed extractor 3 , and the other end of the emulsion delivery pipeline 9 is connected to the feed port of the crystallization kettle 4 , so as to continuously introduce the micro-dispersed emulsion in the micro-dispersed extractor 3 into the crystallization kettle 4 .

[0040] According to the production scale, the volume of the crystallization kettle 4 can be set to 1-10m 3 The bottom discharge port of the crystallization kettle 4 is connected to the feed port pipeline of the transfer pump 5; the discharge pipeline of the transfer pump 5 is connected with a circulation pipeline 6 and a centrifuge feed pipeline 7; the circulation pipeline 6 and the centrifuge feed pipeline 7 are connected in parallel; so that the mixed crystal material in the crystallization kettle 4 is pumped through the feed pump, a part of it is refluxed to the crystallization kettle 4 through the circulation pipeline 6, and the other part is taken out through the centrifuge feed pipeline 7 to the centrifuge for centrifugation, and then separated by solid and liquid to obtain tris(tribromophenoxy)triazine solid crystalline particles.

[0041] The light component outlet at the top of the crystallization kettle 4 is connected to the feed inlet pipeline of the condenser 8 so that the condenser 8 can continuously condense and recover the dichloromethane volatilized under the action of hot water during the continuous stripping crystallization process.

[0042] The present invention also provides a method for continuous steam stripping crystallization of tris(tribromophenoxy)triazine, which comprises: continuously preparing micro-dispersed emulsion and continuously steam stripping crystallization.

[0043] The method for continuously preparing a micro-dispersed emulsion comprises: adding 15-20wt% of a dichloromethane solution of tris(tribromophenoxy)triazine and hot water in a crystallization kettle 4 in advance, and controlling the material temperature in the crystallization kettle 4 to be 60-95° C.; then controlling the dichloromethane solution of tris(tribromophenoxy)triazine and hot water to be continuously fed to a micro-dispersed extractor 3 simultaneously to obtain a micro-dispersed emulsion, and continuously discharging the emulsion to the crystallization kettle 4.

[0044] In the method for continuously preparing a microdispersed emulsion, the content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 10-50wt%; preferably, the content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 35-45wt%; more preferably, the content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 40wt%.

[0045] In the method for continuously preparing a microdispersed emulsion, the hot water temperature is controlled at 60-95°C, preferably 75-85°C, more preferably 80°C; the temperature of the dichloromethane solution of tris(tribromophenoxy)triazine is controlled at 20-40°C, preferably 25-35°C, more preferably 30°C.

[0046] In the method for continuously preparing a micro-dispersed emulsion, the mass ratio of the hot water added in advance to the dichloromethane solution of tris(tribromophenoxy)triazine in the crystallization kettle 4 is 1-10:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously introduced into the micro-dispersed extractor 3 is 1-10:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance to the crystallization kettle 4 is equal to the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously introduced into the micro-dispersed extractor 3.

[0047] Preferably, the mass ratio of the hot water added in advance to the dichloromethane solution of tris(tribromophenoxy)triazine in the crystallization kettle 4 is 2-5:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously introduced into the micro-dispersion extractor 3 is 2-5:1.

[0048] The continuous stripping crystallization method comprises the following steps: the micro-dispersed emulsion is continuously fed into the crystallization kettle 4, and the temperature of the material in the crystallization kettle 4 is maintained at 60-95° C.; while the crystallization kettle 4 continuously receives the micro-dispersed emulsion from the micro-dispersed extractor 3, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6 under the action of the material transfer pump 5, and the other part is extracted and centrifuged in a centrifuge, and then subjected to solid-liquid separation to obtain tris(tribromophenoxy)triazine solid crystal particles (wet material); meanwhile, in the continuous crystallization process, the solvent dichloromethane of the dichloromethane solution of tris(tribromophenoxy)triazine is volatilized under the action of hot water, and is recovered after condensation in a condenser 8.

[0049] In the continuous steam stripping crystallization, the material in the crystallization kettle 4 is preferably maintained at 75-85°C, more preferably 80°C.

[0050] In the continuous stripping crystallization, the residence time of the micro-dispersed emulsion in the crystallization kettle 4 is 30-60 minutes.

[0051] In the continuous stripping crystallization, under the action of the material transfer pump 5, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6, and the other part is extracted to the centrifuge with a reflux ratio of 1-5:1.

[0052] In the continuous stripping crystallization, in order to maintain the operational stability of the continuous stripping crystallization, the absolute dry mass of tri(tribromophenoxy)triazine in the dichloromethane solution of tri(tribromophenoxy)triazine continuously fed to the micro-dispersed extractor 3 is controlled to be equal to the absolute dry mass of tri(tribromophenoxy)triazine in the mixed crystal material extracted to the centrifuge.

[0053] In the continuous stripping crystallization, the liquid (water) recovered from the centrifuge and solid-liquid separation can be heated again to hot water and reused in the continuous preparation of micro-dispersed emulsion step, and then fed again to the micro-dispersed extractor 3 to contact with the dichloromethane solution of tris(tribromophenoxy)triazine.

[0054] The following will be combined with the specific embodiments of the present invention to clearly and completely describe the technical solutions of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] Example 1

[0056] like Figure 1 As shown, this embodiment provides a device for continuous stripping crystallization of tris(tribromophenoxy)triazine, comprising: a micro-dispersed extractor 3, a crystallization kettle 4, a material transfer pump 5, and a condenser 8.

[0057] The micro-dispersed extractor 3 is fixedly connected with a hot water supply pipeline 1, a liquid feed pipeline 2, and an emulsion delivery pipeline 9. The hot water supply pipeline 1 is connected to the main inlet of the micro-dispersed extractor 3 so as to continuously supply hot water to the micro-dispersed extractor 3; the liquid feed pipeline 2 is connected to the side inlet of the micro-dispersed extractor 3 so as to continuously feed a dichloromethane solution of tris(tribromophenoxy)triazine to the micro-dispersed extractor 3.

[0058] The micro-dispersion extractor 3 is used to perform micro-dispersion extraction on a dichloromethane solution of tris(tribromophenoxy)triazine and hot water to obtain a micro-dispersion emulsion; the micro-dispersion extractor 3 consists of a microporous disperser and an extractor, the microporous disperser contains 20 organic phase dispersion sieve holes with a diameter of 0.5 mm, and a Y-shaped oil-water intersection channel structure with a hydraulic diameter of 4 mm; the inner wall of the extractor is evenly provided with symmetrically distributed mushroom-shaped protrusions, and the height of the mushroom-shaped protrusions is 1 / 5 of the inner diameter of the extractor; the function of the extractor is, on the one hand, to extract part of the tris(tribromophenoxy)triazine in the hot water extraction solution, and on the other hand, to improve the mixing uniformity of hot water and the dichloromethane solution of tris(tribromophenoxy)triazine in the micro-dispersion emulsion.

[0059] One end of the emulsion delivery pipeline 9 is connected to the discharge port of the micro-dispersed extractor 3 , and the other end of the emulsion delivery pipeline 9 is connected to the feed port of the crystallization kettle 4 , so as to continuously introduce the micro-dispersed emulsion in the micro-dispersed extractor 3 into the crystallization kettle 4 .

[0060] According to the production scale, the volume of the crystallization kettle 4 can be set to 5m 3 The bottom discharge port of the crystallization kettle 4 is connected to the feed port pipeline of the transfer pump 5; the discharge pipeline of the transfer pump 5 is connected with a circulation pipeline 6 and a centrifuge feed pipeline 7; the circulation pipeline 6 and the centrifuge feed pipeline 7 are connected in parallel; so that the mixed crystal material in the crystallization kettle 4 is pumped through the feed pump, a part of it is refluxed to the crystallization kettle 4 through the circulation pipeline 6, and the other part is taken out through the centrifuge feed pipeline 7 to the centrifuge for centrifugation, and then separated by solid and liquid to obtain tris(tribromophenoxy)triazine solid crystalline particles.

[0061] The light component outlet at the top of the crystallization kettle 4 is connected to the feed inlet pipeline of the condenser 8 so that the condenser 8 can continuously condense and recover the dichloromethane volatilized under the action of hot water during the continuous stripping crystallization process.

[0062] This embodiment also provides a method for continuous stripping crystallization of tris(tribromophenoxy)triazine using the above-mentioned device, specifically:

[0063] 1. Continuous preparation of microdispersed emulsion

[0064] A dichloromethane solution of tris(tribromophenoxy)triazine and hot water in an amount of 20 wt% by volume of the kettle are added to the crystallization kettle 4 in advance, and the material temperature in the crystallization kettle 4 is controlled to be 80° C. Then, the dichloromethane solution of tris(tribromophenoxy)triazine and hot water are controlled to be continuously fed to the micro-dispersed extractor 3 at the same time to obtain a micro-dispersed emulsion, and the micro-dispersed emulsion is continuously discharged to the crystallization kettle 4.

[0065] The content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 40 wt %.

[0066] The temperature of the hot water fed to the microdispersion extractor 3 was 80°C; the temperature of the dichloromethane solution of tris(tribromophenoxy)triazine was 30°C.

[0067] The mass ratio of the hot water added in advance to the dichloromethane solution of tris(tribromophenoxy)triazine in the crystallization kettle 4 is 2:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3 is 2:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance to the crystallization kettle 4 is equal to the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3.

[0068] 2. Continuous stripping crystallization

[0069] The micro-dispersed emulsion is continuously fed to the crystallization kettle 4, and the material in the crystallization kettle 4 is kept at 80° C. While the crystallization kettle 4 continuously receives the micro-dispersed emulsion from the micro-dispersed extractor 3, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6 under the action of the material transfer pump 5, and the other part is taken out to the centrifuge for centrifugation, and then subjected to solid-liquid separation to obtain tris(tribromophenoxy)triazine solid crystal particles (wet material); at the same time, in the continuous crystallization process, the solvent dichloromethane of the dichloromethane solution of tris(tribromophenoxy)triazine is volatilized under the action of hot water, and is recovered after condensation by the condenser 8.

[0070] The tris(tribromophenoxy)triazine solid crystalline particles obtained by the continuous crystallization are particles with regular shape and uniform particle size, without agglomeration or caking, and the residual amount of organic solvent (dichloromethane) is 0g / kg; after the tris(tribromophenoxy)triazine solid crystalline particles (wet material) are dried to remove moisture, a tris(tribromophenoxy)triazine solid product with an average particle size of 0.9mm can be obtained.

[0071] The residence time of the micro-dispersed emulsion in the crystallization kettle 4 is 45 minutes.

[0072] Under the action of the material transfer pump 5, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6, and the other part is taken out to the centrifuge with a reflux ratio of 2.5:1.

[0073] In order to maintain the operational stability of the continuous steam stripping crystallization, the absolute dry mass of tri(tribromophenoxy)triazine in the dichloromethane solution of tri(tribromophenoxy)triazine continuously fed to the micro-dispersed extractor 3 is controlled to be equal to the absolute dry mass of tri(tribromophenoxy)triazine in the mixed crystallization material taken out to the centrifuge.

[0074] In the continuous stripping crystallization, the liquid (water) recovered from the centrifuge and solid-liquid separation can be heated again to hot water and reused in the continuous preparation of micro-dispersed emulsion step, and then fed again to the micro-dispersed extractor 3 to contact with the dichloromethane solution of tris(tribromophenoxy)triazine.

[0075] Example 2

[0076] The continuous stripping crystallization apparatus of tris(tribromophenoxy)triazine used in this embodiment is the same as that in Example 1.

[0077] This embodiment provides a method for continuous stripping crystallization of tris(tribromophenoxy)triazine using the above-mentioned device, specifically:

[0078] 1. Continuous preparation of microdispersed emulsion

[0079] A dichloromethane solution of tris(tribromophenoxy)triazine and hot water in an amount of 15 wt% by volume of the kettle are added to the crystallization kettle 4 in advance, and the material temperature in the crystallization kettle 4 is controlled to be 80° C. Then, the dichloromethane solution of tris(tribromophenoxy)triazine and hot water are controlled to be continuously fed to the micro-dispersed extractor 3 at the same time to obtain a micro-dispersed emulsion, and the micro-dispersed emulsion is continuously discharged to the crystallization kettle 4.

[0080] The content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 40 wt %.

[0081] The temperature of the hot water fed to the microdispersion extractor 3 was 80°C; the temperature of the dichloromethane solution of tris(tribromophenoxy)triazine was 30°C.

[0082] The mass ratio of the hot water added in advance to the dichloromethane solution of tris(tribromophenoxy)triazine in the crystallization kettle 4 is 2:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3 is 2:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance to the crystallization kettle 4 is equal to the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3.

[0083] 2. Continuous stripping crystallization

[0084] The micro-dispersed emulsion is continuously fed to the crystallization kettle 4, and the material in the crystallization kettle 4 is kept at 80° C. While the crystallization kettle 4 continuously receives the micro-dispersed emulsion from the micro-dispersed extractor 3, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6 under the action of the material transfer pump 5, and the other part is taken out to the centrifuge for centrifugation, and then subjected to solid-liquid separation to obtain tris(tribromophenoxy)triazine solid crystal particles (wet material); at the same time, in the continuous crystallization process, the solvent dichloromethane of the dichloromethane solution of tris(tribromophenoxy)triazine is volatilized under the action of hot water, and is recovered after condensation by the condenser 8.

[0085] The tris(tribromophenoxy)triazine solid crystalline particles obtained by the continuous crystallization are particles with regular shape and uniform particle size, without agglomeration or caking, and the residual amount of organic solvent (dichloromethane) is 0g / kg; after the tris(tribromophenoxy)triazine solid crystalline particles (wet material) are dried to remove moisture, a tris(tribromophenoxy)triazine solid product with an average particle size of 0.7mm can be obtained.

[0086] The residence time of the micro-dispersed emulsion in the crystallization kettle 4 is 40 minutes.

[0087] Under the action of the material transfer pump 5, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6, and the other part is taken out to the centrifuge with a reflux ratio of 3:1.

[0088] In order to maintain the operational stability of the continuous steam stripping crystallization, the absolute dry mass of tri(tribromophenoxy)triazine in the dichloromethane solution of tri(tribromophenoxy)triazine continuously fed to the micro-dispersed extractor 3 is controlled to be equal to the absolute dry mass of tri(tribromophenoxy)triazine in the mixed crystallization material taken out to the centrifuge.

[0089] In the continuous stripping crystallization, the liquid (water) recovered from the centrifuge and solid-liquid separation can be heated again to hot water and reused in the continuous preparation of micro-dispersed emulsion step, and then fed again to the micro-dispersed extractor 3 to contact with the dichloromethane solution of tris(tribromophenoxy)triazine.

[0090] Example 3

[0091] The continuous stripping crystallization apparatus of tris(tribromophenoxy)triazine used in this embodiment is the same as that in Example 1.

[0092] This embodiment provides a method for continuous stripping crystallization of tris(tribromophenoxy)triazine using the above-mentioned device, specifically:

[0093] 1. Continuous preparation of microdispersed emulsion

[0094] A dichloromethane solution of tris(tribromophenoxy)triazine and hot water in an amount of 18 wt% by volume of the kettle are added to the crystallization kettle 4 in advance, and the material temperature in the crystallization kettle 4 is controlled to be 80° C. Then, the dichloromethane solution of tris(tribromophenoxy)triazine and hot water are controlled to be continuously fed to the micro-dispersed extractor 3 at the same time to obtain a micro-dispersed emulsion, and the micro-dispersed emulsion is continuously discharged to the crystallization kettle 4.

[0095] The content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 40 wt %.

[0096] The temperature of the hot water fed to the microdispersion extractor 3 was 80°C; the temperature of the dichloromethane solution of tris(tribromophenoxy)triazine was 30°C.

[0097] The mass ratio of the hot water added in advance to the dichloromethane solution of tris(tribromophenoxy)triazine in the crystallization kettle 4 is 5:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3 is 5:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance to the crystallization kettle 4 is equal to the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3.

[0098] 2. Continuous stripping crystallization

[0099] The micro-dispersed emulsion is continuously fed to the crystallization kettle 4, and the material in the crystallization kettle 4 is kept at 80° C. While the crystallization kettle 4 continuously receives the micro-dispersed emulsion from the micro-dispersed extractor 3, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6 under the action of the material transfer pump 5, and the other part is taken out to the centrifuge for centrifugation, and then subjected to solid-liquid separation to obtain tris(tribromophenoxy)triazine solid crystal particles (wet material); at the same time, in the continuous crystallization process, the solvent dichloromethane of the dichloromethane solution of tris(tribromophenoxy)triazine is volatilized under the action of hot water, and is recovered after condensation by the condenser 8.

[0100] The tris(tribromophenoxy)triazine solid crystalline particles obtained by the continuous crystallization are particles with regular shape and uniform particle size, without agglomeration or caking, and the residual amount of organic solvent (dichloromethane) is 0g / kg; after the tris(tribromophenoxy)triazine solid crystalline particles (wet material) are dried to remove moisture, a tris(tribromophenoxy)triazine solid product with an average particle size of 0.7mm can be obtained.

[0101] The residence time of the micro-dispersed emulsion in the crystallization kettle 4 is 50 min.

[0102] Under the action of the material transfer pump 5, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6, and the other part is taken out to the centrifuge with a reflux ratio of 2.5:1.

[0103] In order to maintain the operational stability of the continuous steam stripping crystallization, the absolute dry mass of tri(tribromophenoxy)triazine in the dichloromethane solution of tri(tribromophenoxy)triazine continuously fed to the micro-dispersed extractor 3 is controlled to be equal to the absolute dry mass of tri(tribromophenoxy)triazine in the mixed crystallization material taken out to the centrifuge.

[0104] In the continuous stripping crystallization, the liquid (water) recovered from the centrifuge and solid-liquid separation can be heated again to hot water and reused in the continuous preparation of micro-dispersed emulsion step, and then fed again to the micro-dispersed extractor 3 to contact with the dichloromethane solution of tris(tribromophenoxy)triazine.

[0105] Example 4

[0106] The continuous stripping crystallization apparatus of tris(tribromophenoxy)triazine used in this embodiment is the same as that in Example 1.

[0107] This embodiment provides a method for continuous stripping crystallization of tris(tribromophenoxy)triazine using the above-mentioned device, specifically:

[0108] 1. Continuous preparation of microdispersed emulsion

[0109] A dichloromethane solution of tris(tribromophenoxy)triazine and hot water in an amount of 20 wt% by volume of the kettle are added to the crystallization kettle 4 in advance, and the material temperature in the crystallization kettle 4 is controlled to be 80° C. Then, the dichloromethane solution of tris(tribromophenoxy)triazine and hot water are controlled to be continuously fed to the micro-dispersed extractor 3 at the same time to obtain a micro-dispersed emulsion, and the micro-dispersed emulsion is continuously discharged to the crystallization kettle 4.

[0110] The content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 40 wt %.

[0111] The temperature of the hot water fed to the microdispersion extractor 3 was 80°C; the temperature of the dichloromethane solution of tris(tribromophenoxy)triazine was 30°C.

[0112] The mass ratio of the hot water added in advance to the dichloromethane solution of tris(tribromophenoxy)triazine in the crystallization kettle 4 is 2:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3 is 2:1; the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance to the crystallization kettle 4 is equal to the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously passed into the micro-dispersed extractor 3.

[0113] 2. Continuous stripping crystallization

[0114] The micro-dispersed emulsion is continuously fed to the crystallization kettle 4, and the material in the crystallization kettle 4 is kept at 80° C. While the crystallization kettle 4 continuously receives the micro-dispersed emulsion from the micro-dispersed extractor 3, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6 under the action of the material transfer pump 5, and the other part is taken out to the centrifuge for centrifugation, and then subjected to solid-liquid separation to obtain tris(tribromophenoxy)triazine solid crystal particles (wet material); at the same time, in the continuous crystallization process, the solvent dichloromethane of the dichloromethane solution of tris(tribromophenoxy)triazine is volatilized under the action of hot water, and is recovered after condensation by the condenser 8.

[0115] The tris(tribromophenoxy)triazine solid crystalline particles obtained by the continuous crystallization are particles with regular shape and uniform particle size, without agglomeration or caking, and the residual amount of organic solvent (dichloromethane) is 0g / kg; after the tris(tribromophenoxy)triazine solid crystalline particles (wet material) are dried to remove moisture, a tris(tribromophenoxy)triazine solid product with an average particle size of 0.8mm can be obtained.

[0116] The residence time of the micro-dispersed emulsion in the crystallization kettle 4 is 50 min.

[0117] Under the action of the material transfer pump 5, a part of the mixed crystal material in the crystallization kettle 4 is refluxed to the crystallization kettle 4 through the circulation pipeline 6, and the other part is taken out to the centrifuge with a reflux ratio of 3.2:1.

[0118] In order to maintain the operational stability of the continuous steam stripping crystallization, the absolute dry mass of tri(tribromophenoxy)triazine in the dichloromethane solution of tri(tribromophenoxy)triazine continuously fed to the micro-dispersed extractor 3 is controlled to be equal to the absolute dry mass of tri(tribromophenoxy)triazine in the mixed crystallization material taken out to the centrifuge.

[0119] In the continuous stripping crystallization, the liquid (water) recovered from the centrifuge and solid-liquid separation can be heated again to hot water and reused in the continuous preparation of micro-dispersed emulsion step, and then fed again to the micro-dispersed extractor 3 to contact with the dichloromethane solution of tris(tribromophenoxy)triazine.

[0120] Comparative Example 1

[0121] Comparative Example 1 adopts the traditional kettle steam stripping intermittent crystallization process, specifically:

[0122] The dichloromethane solution of tris(tribromophenoxy)triazine and hot water are added into a crystallization kettle, and the temperature is raised to 80°C. During the heating process, the solvent dichloromethane is volatilized under the action of hot water, and is recovered after condensation in a condenser. After the distillation is completed, the remaining materials in the kettle are tris(tribromophenoxy)triazine solid and water, which are centrifugally dehydrated to obtain tris(tribromophenoxy)triazine solid crystalline particles.

[0123] The mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added into the crystallization kettle is 2:1; the content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 40wt%; and the temperature of the hot water is controlled to be 80°C; the temperature of the dichloromethane solution of tris(tribromophenoxy)triazine is 30°C, and the temperature of the crystallization kettle is 80°C.

[0124] The solid crystalline particles of tris(tribromophenoxy)triazine obtained by crystallization in Comparative Example 1 were irregular particles with uneven particle sizes, and agglomeration and caking occurred. The residual amount of the organic solvent (dichloromethane) was 13 g / kg.

[0125] Comparative Example 2

[0126] Comparative Example 2 adopts the traditional kettle steam stripping intermittent crystallization process, specifically:

[0127] The dichloromethane solution of tris(tribromophenoxy)triazine and hot water are added into a crystallization kettle, and the temperature is raised to 80°C. During the heating process, the solvent dichloromethane is volatilized under the action of hot water, and is recovered after condensation in a condenser. After the distillation is completed, the remaining materials in the kettle are tris(tribromophenoxy)triazine solid and water, which are centrifugally dehydrated to obtain tris(tribromophenoxy)triazine solid crystalline particles.

[0128] The mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added into the crystallization kettle is 5:1; the content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 40wt%; and the temperature of the hot water is controlled to be 80°C; the temperature of the dichloromethane solution of tris(tribromophenoxy)triazine is 30°C, and the temperature of the crystallization kettle is 80°C.

[0129] The solid crystalline particles of tris(tribromophenoxy)triazine obtained by crystallization in Comparative Example 2 were irregular particles with uneven particle sizes, and agglomeration and caking occurred. The residual amount of the organic solvent (dichloromethane) was 10 g / kg.

[0130] The process parameters and product results in Examples 1-4 and Comparative Examples 1-2 are shown in the following table:

[0131]

[0132] Unless otherwise specified, all percentages used in the present invention are by mass.

[0133] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A continuous stripping crystallization method for tris(tribromophenoxy)triazine, characterized in that: The method comprises the following steps: continuously preparing micro-dispersed emulsion and continuously stripping and crystallizing; The method for continuously preparing a micro-dispersed emulsion comprises: adding a dichloromethane solution of tris(tribromophenoxy)triazine and hot water to a crystallization kettle (4) in advance, and then continuously feeding the dichloromethane solution of tris(tribromophenoxy)triazine and hot water to a micro-dispersed extractor (3) to obtain a micro-dispersed emulsion, and continuously discharging the emulsion to the crystallization kettle (4); In the continuous preparation of the microdisperse emulsion, the dichloromethane solution of tris(tribromophenoxy)triazine continuously fed into the microdisperse extractor (3) has a temperature of 20-40°C, and the hot water has a temperature of 60-95°C; The content of tris(tribromophenoxy)triazine in the dichloromethane solution of tris(tribromophenoxy)triazine is 10-50wt%; The mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance to the crystallization kettle (4) is equal to the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously introduced into the micro-dispersion extractor (3); The continuous steam stripping crystallization method comprises the following steps: a crystallization kettle (4) continuously receives the micro-dispersed emulsion from the micro-dispersed extractor (3), and the temperature of the crystallization kettle is maintained at 60-95° C.; at the same time, under the action of a material transfer pump (5), a part of the mixed crystal material in the crystallization kettle (4) is refluxed to the crystallization kettle (4), and the other part is taken out to a centrifuge for centrifugation, and then subjected to solid-liquid separation to obtain tris(tribromophenoxy)triazine solid crystal particles.

2. The continuous stripping crystallization method of tris(tribromophenoxy)triazine according to claim 1, characterized in that: In the continuous preparation of the micro-dispersed emulsion, the mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine added in advance into the crystallization kettle (4) is 1-10:1; The mass ratio of the hot water and the dichloromethane solution of tris(tribromophenoxy)triazine continuously introduced into the micro-dispersion extractor (3) is 1-10:

1.

3. The continuous stripping crystallization method of tris(tribromophenoxy)triazine according to claim 1, characterized in that: In the continuous steam stripping crystallization, the residence time of the micro-dispersed emulsion in the crystallization kettle (4) is 30-60 minutes.

4. The continuous stripping crystallization method of tris(tribromophenoxy)triazine according to claim 1, characterized in that: In the continuous stripping crystallization, a portion of the mixed crystal material in the crystallization kettle (4) is refluxed to the crystallization kettle (4) under the action of the material transfer pump (5), and the other portion is taken out to the centrifuge at a reflux ratio of 1-5:

1.

5. The continuous stripping crystallization method of tris(tribromophenoxy)triazine according to claim 1, characterized in that: In the continuous steam stripping crystallization, the solvent dichloromethane of the dichloromethane solution of tris(tribromophenoxy)triazine volatilized by heat is continuously collected and recovered after condensation; The liquid recovered from the centrifuge and solid-liquid separation is heated to obtain hot water, which is then fed back to the micro-dispersion extractor (3).

6. The continuous stripping crystallization method of tris(tribromophenoxy)triazine according to claim 1, characterized in that: The absolute dry mass of tri(tribromophenoxy)triazine in the dichloromethane solution of tri(tribromophenoxy)triazine continuously fed to the micro-disperse extractor (3) is controlled to be equal to the absolute dry mass of tri(tribromophenoxy)triazine in the mixed crystal material taken out to the centrifuge.

7. A continuous stripping crystallization device for tris(tribromophenoxy)triazine for implementing the method according to any one of claims 1 to 6, characterized in that: It comprises: a micro-dispersion extractor (3), a crystallization kettle (4), a material transfer pump (5), and a condenser (8); The discharge port of the micro-dispersed extractor (3) is connected to the feed port of the crystallization kettle (4); the bottom discharge port of the crystallization kettle (4) is connected to the feed port pipeline of the transfer pump (5); the discharge pipeline of the transfer pump (5) is connected to the circulation pipeline (6) and the centrifuge feed pipeline (7); the circulation pipeline (6) and the centrifuge feed pipeline (7) are connected in parallel; The light component outlet at the top of the crystallization kettle (4) is connected to the feed inlet pipeline of the condenser (8); The micro-dispersed extractor (3) is used to continuously receive and process the dichloromethane solution and hot water of tris(tribromophenoxy)triazine to obtain a micro-dispersed emulsion; The micro-dispersion extractor (3) is composed of a microporous disperser and an extractor; The microporous disperser contains 15-20 organic phase dispersion sieve holes with a diameter of 0.5-2 mm, and at least one T-shaped or Y-shaped oil-water intersection channel structure with a hydraulic diameter of 3-5 mm; The inner wall of the extractor is evenly provided with symmetrically distributed mushroom-shaped protrusions, and the height of the mushroom-shaped protrusions is 1 / 5-2 / 5 of the inner diameter of the extractor.

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