A vaporization process for preparing high-purity bromine

Abstract

The present invention relates to the field of bromine preparation, and in particular to a vaporization process for preparing high-purity bromine, comprising raw material pretreatment, oxidation reaction, graded recovery of gaseous bromine, enhanced extraction of residual bromine in the liquid phase, organic extraction separation, and distillation purification. Bromine hydrolysis is suppressed by precisely controlling reaction conditions, and efficient bromine vaporization and separation is achieved through multi-stage condensation and segmented evaporation. The tail gas is treated in a composite purification system to ensure compliance with environmental standards. Extraction and distillation synergistically remove impurities, ultimately yielding high-purity bromine. This process overcomes the low yield and high energy consumption shortcomings of traditional methods, combining the advantages of high efficiency, energy conservation, and environmental protection, making it suitable for large-scale industrial applications.

Description

Technical Field

[0001] The present invention relates to the field of bromine preparation, and in particular to a vaporization process for preparing high-purity bromine. Background Art

[0002] Bromine, an important basic chemical raw material, is widely used in pharmaceutical synthesis, flame retardant materials, pesticide manufacturing, and other fields. Currently, industrial bromine production primarily relies on brine oxidation or electrolysis. However, these traditional processes present numerous bottlenecks, severely restricting improvements in production efficiency and product quality.

[0003] First, imprecise control of reaction conditions leads to significant bromine loss. During the oxidation reaction, if the pH or temperature of the reaction system fluctuates, bromine is susceptible to reversible hydrolysis with water to produce hypobromous acid and hydrobromic acid. This not only reduces the actual bromine yield but also increases the difficulty of subsequent separation and purification.

[0004] Secondly, the separation and recovery process is inefficient. Traditional methods rely on a single condensation or evaporation step, which makes it difficult to fully capture gaseous bromine, resulting in a large amount of bromine remaining in the reaction liquid or exhaust gas. In addition, high evaporation energy consumption and insufficient condensation efficiency further increase production costs. Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention provides a vaporization process for preparing high-purity bromine. This equipment precisely controls reaction conditions and utilizes the synergistic effects of multi-stage condensation and segmented evaporation, extraction, and distillation to obtain high-purity bromine, thereby overcoming the shortcomings of traditional methods such as low yield and high energy consumption. This is achieved specifically through the following technical solutions.

[0006] The present invention provides a vaporization process for preparing high-purity bromine, comprising the following steps:

[0007] Step 1, raw material pretreatment: dilute the bromine-containing raw material and adjust it to an acidic environment to obtain a reaction stock solution;

[0008] Step 2, oxidation reaction: The reaction solution is heated to a temperature higher than the boiling point of bromine, and a mixture of carbon dioxide and chlorine is introduced to react to generate gaseous bromine;

[0009] Step 3, blowing and collecting: introducing carrier gas into the reaction system, blowing out the gaseous bromine and recovering it through multi-stage condensation, while treating the tail gas;

[0010] Step 4, vaporization and collection: the reaction liquid is subjected to multi-stage evaporation to evaporate the residual bromine and recover it by condensation;

[0011] Step 5, extraction and separation: the bromine solution recovered by condensation is mixed with an organic solvent for extraction, and the organic phase is separated;

[0012] Step 6, distillation and purification: distill the organic phase to separate high-purity bromine and recover the solvent.

[0013] Preferably, in step 1, the bromine-containing raw material is bromine-containing brine or bromine salt solution, the bromide ion concentration in the diluted solution is 20 g / L to 45 g / L, the pH is adjusted to 0.5 to 2.0, the reaction temperature is 40° C. to 50° C., and the reaction time is 20 to 30 minutes.

[0014] Preferably, in step 2, the oxidizing mixed gas is a mixed gas of CO2 and Cl2 with a volume ratio of 1:3 to 5; the reaction temperature is 60°C to 90°C, and the reaction is terminated when the bromide ion concentration in the reaction solution is lower than 0.1 g / L.

[0015] Preferably, in step 3, the multi-stage condensation includes a first-stage water cooling and a second-stage cryogenic cooling, and the first-stage water cooling is connected in parallel with the second-stage cryogenic cooling in series.

[0016] Preferably, in step 4, the multi-stage evaporation includes a primary evaporation and a secondary evaporation, and the primary evaporation is connected in parallel and then in series with the secondary evaporation.

[0017] Preferably, in step 5, the organic solvent is xylene, and the volume ratio of xylene to the bromine solution is 2-3:1-2.

[0018] Preferably, in step 6, the distillation conditions include: tower bottom temperature 120°C to 140°C, tower top temperature 50°C to 58°C, tower pressure 80kPa to 100kPa, and reflux ratio 2 to 4:1.

[0019] Preferably, in step 3, the tail gas is treated in sequence through an alkaline spray tower and an activated carbon adsorption tower, and the alkaline solution in the alkaline spray tower is an 8% to 15% NaOH solution.

[0020] Preferably, the temperature of the first-stage water cooling is 30°C to 50°C, and the temperature of the second-stage deep cooling is 5°C to 10°C.

[0021] Preferably, the temperature of the first-stage evaporation is 70°C to 90°C, and the temperature of the second-stage evaporation is 120°C to 150°C.

[0022] After adopting the above technical solution, the beneficial effects of the present invention are:

[0023] 1. The present invention effectively inhibits the side reaction of bromine hydrolysis by dynamically controlling the pH and temperature of the reaction system. It also combines multi-stage condensation and segmented evaporation technology to enhance the capture efficiency of gaseous bromine, significantly reducing the loss of effective ingredients, and ultimately obtaining a high-purity product through distillation and purification.

[0024] 2. The present invention optimizes the design of thermal energy cascade utilization and realizes efficient energy transfer in the multi-stage processing unit. In addition, the extractant is recycled after distillation, which reduces raw material consumption and saves energy and reduces consumption in multiple links.

[0025] 3. The present invention adopts a composite tail gas purification system to completely eliminate harmful gas emissions through the synergistic effect of chemical neutralization and physical adsorption.

[0026] 4. The integrated design of the impurity separation step of the present invention improves efficiency, shortens the processing cycle, and comprehensively reduces equipment investment and operating costs. DETAILED DESCRIPTION

[0027] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present invention by illustrating examples of the present invention.

[0028] The present invention provides a vaporization process for preparing high-purity bromine, which specifically comprises the following steps:

[0029] Step 1: Raw material pretreatment

[0030] Dilute the bromine-containing brine or bromine salt solution until the Br - The concentration is 20 g / L to 45 g / L, concentrated sulfuric acid is slowly added to the solution, and the pH of the solution is adjusted to 0.5 to 2.0 to prepare a reaction stock solution.

[0031] In the above process, the temperature is controlled at 40°C to 50°C, and the reaction time is 20min to 30min.

[0032] In the above steps, Br - Concentration adjustment makes it easier to balance reaction rate and yield. Too high a concentration may cause the reaction to be too intense or Br2 to precipitate prematurely, increasing the difficulty of handling. Too low a concentration will reduce the reaction rate.

[0033] In addition, the pH of the solution is adjusted to 0.5-2.0 to maintain a strong acid environment in the reaction solution, which is convenient for the subsequent oxidation reaction; and after the subsequent oxidation to generate Br2, a hydrolysis reaction will occur simultaneously:

[0034] Br2+H2O→HBrO+H + +Br -

[0035] When the reaction solution is in a strong acid environment, the above hydrolysis reaction will be inhibited, thereby reducing the loss of Br2.

[0036] Among them, the dilution and heat dissipation effect of concentrated sulfuric acid is used to adjust the temperature of the reaction solution to 40℃~50℃. Since the boiling point of Br2 is 59℃, the temperature is appropriately raised without exceeding the above temperature to increase the molecular thermal motion and promote the oxidation reaction.

[0037] Step 2: Oxidation reaction

[0038] The reaction solution obtained in step 1 was introduced into an enameled reactor, and the reaction solution was heated to 60°C to 90°C. A mixed gas of CO2 and Cl2 was introduced according to a volume ratio of CO2:Cl2 of 1:3 to 5. The Br content in the reaction solution was monitored in real time by a concentration sensor. - Concentration, when Br - When the concentration was lower than 0.1 g / L, the reaction was terminated.

[0039] In the above process, Cl2 is introduced to produce a chemical reaction: Cl2+2Br − →2Cl − +Br2; the temperature is controlled at 60℃~90℃ because the boiling point of Br2 is 59℃, and it can be vaporized within this temperature range, thereby achieving the initial separation of Br2 and the solution; in addition, high temperature increases the ion activity in the solution, thereby promoting the above-mentioned oxidation reaction.

[0040] Step 3: Blowing and collecting

[0041] Air is introduced from one side of the reactor and gas is collected on the other side of the reactor. The collected gas is liquefied through multi-stage condensation. The condensed liquid is collected as the first-level bromine liquid for standby use. The condensed output gas passes through the alkaline spray tower and the activated carbon adsorption tower in sequence.

[0042] Among them, the multi-stage condensation includes a first-stage water cooling with a temperature of 30℃~50℃ and a second-stage deep cooling with a temperature of 5℃~10℃. Multiple first-stage water cooling units are connected in parallel and then in series with the second-stage deep cooling units.

[0043] In the process of recovering Br2 from the gas through multi-stage condensation, the first-stage water cooling and the second-stage deep cooling are connected, that is, multiple first-stage water cooling is used to ensure the efficiency of Br2 condensation, and the second-stage deep cooling is used to minimize the residual amount of Br2 in the gas.

[0044] Among them, the spray liquid in the alkaline spray tower is 8% to 15% NaOH solution.

[0045] In step 2, the Br2 produced by the reaction vaporizes at a temperature of 60°C to 90°C. Therefore, air is introduced into the reactor to blow out the Br2 concentrated in the upper layer of the reactor. Since the gas in the reactor contains CO2, Cl2 and Br2, the Br2 in the gas is condensed and liquefied by utilizing the low boiling point of Br2 to be recovered for later use, which is convenient for subsequent further purification.

[0046] The CO2, Cl2 and residual Br2 in the tail gas react chemically with the spray liquid in the alkaline spray tower to remove harmful gases in the tail gas; in addition, a small amount of incompletely reacted tail gas is adsorbed by the activated carbon adsorption tower to avoid leakage of harmful gases.

[0047] Step 4: Vaporization Collection

[0048] The reaction liquid in the reactor is subjected to multi-stage evaporation to evaporate the Br2 in the reaction liquid. The evaporated gas is liquefied through multi-stage condensation. The condensed liquid is collected as a secondary bromine liquid for standby use. The condensed output gas passes through an alkaline spray tower and an activated carbon adsorption tower in sequence.

[0049] Among them, the multi-stage evaporation includes a first-stage evaporation at a temperature of 70°C to 90°C and a second-stage evaporation at a temperature of 120°C to 150°C. Multiple first-stage evaporations are connected in parallel and in series with the second-stage evaporation. The multiple parallel first-stage evaporations can achieve the highest efficiency in evaporating Br2, but some bromine will still remain in the reaction liquid. Therefore, the remaining Br2 is further evaporated through the second-stage evaporation.

[0050] The time for the first-stage evaporation is 20 to 30 minutes, and the time for the second-stage evaporation is 15 to 25 minutes.

[0051] The use of segmented distillation can, on the one hand, increase the distillation speed, and on the other hand, reduce energy consumption, saving energy and protecting the environment.

[0052] The multi-stage condensation, alkaline spray tower and activated carbon adsorption tower in this step are arranged in the same manner as in step 3.

[0053] Step 5: Extraction and separation

[0054] The first-stage bromine solution and the second-stage bromine solution are mixed, and xylene is added in a volume ratio of xylene: bromine solution = 2-3:1-2, and the organic phase is extracted and separated.

[0055] Since the preparation process of the primary bromine liquid and the secondary bromine liquid is to achieve the vaporization of Br2 by heating and then collect it by condensation, the primary bromine liquid and the secondary bromine liquid will contain some water and salt impurities. The bromine is extracted by xylene, thereby achieving effective separation of bromine and the above impurities.

[0056] Step 6: Distillation and purification

[0057] The organic phase obtained in step 5 is transported to a distillation tower for distillation. The gas produced by the distillation is collected and condensed to obtain high-purity Br2. The remaining liquid phase of the distillation is recycled.

[0058] In the above-mentioned process of completing the distillation using a distillation tower, the tower bottom temperature is 120°C to 140°C, the tower top temperature is 50°C to 58°C, the pressure in the tower is 80kPa to 100kPa, and the reflux ratio is 2 to 4:1.

[0059] In the above steps, the condensation temperature is 15°C to 30°C.

[0060] During this process, considering that the boiling point of Br2 is 59°C and the boiling point of xylene is 138°C~145°C, the bottom temperature of the tower is controlled at 120°C~140°C and the top temperature of the tower is controlled at 50°C~58°C, so that the extract is always in a distillation state in the distillation tower, thereby efficiently distilling out the Br2 inside the organic phase.

[0061] The evaporated gas is condensed into high-purity Br2, and the remaining liquid phase after distillation is xylene, which can be reused in the extraction process in step 5 to reduce production costs.

[0062] In order to facilitate further understanding of the present invention, several embodiments and comparative examples of the present invention are given below:

[0063] Example 1

[0064] Step 1: dilute the bromine-containing brine to the Br - The concentration was 35 g / L, concentrated sulfuric acid was slowly added to the solution, the pH of the solution was adjusted to 1.5, the temperature was adjusted to 45° C., and the temperature was kept at 45° C. for 20 minutes to obtain a reaction stock solution.

[0065] Step 2: The reaction solution was introduced into an enameled reactor, heated to 75°C, and a mixed gas of CO2 and Cl2 was introduced at a volume ratio of CO2:Cl2 of 1:3 until Br - When the concentration is lower than 0.1 g / L, the reaction is terminated.

[0066] Step 3: Use air to blow out the upper layer of gas in the reactor, and condense it in sequence using primary water cooling at 40°C and secondary deep cooling at 10°C. Collect the condensate for later use, and spray the condensed tail gas with 10% NaOH solution for absorption and activated carbon adsorption.

[0067] Step 4: evaporate the reaction liquid in the reactor in sequence by using a primary evaporation at 80°C and a secondary evaporation at 140°C, the primary evaporation time is 30 min, and the secondary evaporation time is 15 min. The evaporated gas is condensed in sequence by using a primary water cooling at 40°C and a secondary deep cooling at 10°C. The condensate is collected for later use, and the condensed tail gas is sprayed with a 10% NaOH solution for absorption and activated carbon adsorption.

[0068] Step 5: Mix the condensates in step 3 and step 4, add xylene twice the volume of the condensate, and extract and separate the organic phase.

[0069] Step 6: The organic phase is transported to a distillation tower with a bottom temperature of 130°C, a top temperature of 57°C, a pressure of 80 kPa, and a reflux ratio of 4:1. The gas produced by distillation is condensed at 20°C to obtain high-purity Br2. The remaining xylene from the distillation is reused in step 5.

[0070] Example 2

[0071] This example is based on Example 1, and the parameters of the reaction solution in step 1 are adjusted, specifically:

[0072] Step 1: dilute the bromine-containing brine to the Br - The concentration was 35 g / L, concentrated sulfuric acid was slowly added to the solution, the pH of the solution was adjusted to 2.0, the temperature was adjusted to 40° C., and the temperature was kept at 40° C. for 20 minutes to obtain a reaction stock solution.

[0073] The remaining steps and conditions are the same as those in Example 1.

[0074] Example 3

[0075] This embodiment is based on the embodiment 1, and the ratio of the mixed gas in step 2 is adjusted, specifically:

[0076] Step 2: The reaction solution was introduced into an enameled reactor, heated to 75°C, and a mixed gas of CO2 and Cl2 was introduced at a volume ratio of CO2:Cl2 of 1:5 until Br - When the concentration is lower than 0.1 g / L, the reaction is terminated.

[0077] The remaining steps and conditions are the same as those in Example 1.

[0078] Example 4

[0079] This embodiment is based on the embodiment 1, and adjusts the temperature of the first-stage water cooling in step 3 and step 4, specifically:

[0080] Step 3: Use air to blow out the upper layer of gas in the reactor, and condense it in sequence using primary water cooling at 50°C and secondary deep cooling at 10°C. Collect the condensate for later use, and spray the condensed tail gas with 10% NaOH solution for absorption and activated carbon adsorption.

[0081] Step 4: evaporate the reaction liquid in the reactor in sequence by using a primary evaporation at 80°C and a secondary evaporation at 140°C, the primary evaporation time is 30 min, and the secondary evaporation time is 15 min. The evaporated gas is condensed in sequence by using a primary water cooling at 50°C and a secondary deep cooling at 10°C. The condensate is collected for later use, and the condensed tail gas is sprayed with a 10% NaOH solution for absorption and activated carbon adsorption.

[0082] The remaining steps and conditions are the same as those in Example 1.

[0083] Example 5

[0084] This embodiment is based on Example 1, and the parameters of the distillation tower in step 6 are adjusted, specifically:

[0085] Step 6: The organic phase is transported to a distillation tower with a bottom temperature of 120°C, a top temperature of 55°C, a pressure of 80 kPa, and a reflux ratio of 4:1. The gas produced by distillation is condensed at 20°C to obtain high-purity Br2. The remaining xylene from the distillation is reused in step 5.

[0086] The remaining steps and conditions are the same as those in Example 1.

[0087] Comparative Example 1

[0088] This comparative example is based on Example 1, but the gas introduced in step 2 is adjusted and no CO2 is added. Specifically:

[0089] Step 2: Put the reaction solution into the enameled reactor, heat it to 75℃, and introduce Cl2 until Br - When the concentration is lower than 0.1 g / L, the reaction is terminated.

[0090] The remaining steps and conditions are the same as those in Example 1.

[0091] Comparative Example 2

[0092] This embodiment is based on the embodiment 1, and the condensation method in step 3 and step 4 is adjusted, and the graded condensation is no longer used. Specifically:

[0093] Step 3: Use air to blow out the upper layer of gas in the reactor, condense it in a condensation environment of 10°C, collect the condensate for later use, and spray the condensed tail gas with 10% NaOH solution for absorption and activated carbon adsorption in turn.

[0094] Step 4: The reaction liquid in the reactor was evaporated in sequence by using a primary evaporation at 80°C and a secondary evaporation at 140°C. The primary evaporation time was 30 min and the secondary evaporation time was 15 min. The evaporated gas was condensed in a condensation environment at 10°C, and the condensate was collected for later use. The condensed tail gas was sprayed with a 10% NaOH solution for absorption and activated carbon adsorption.

[0095] The remaining steps and conditions are the same as those in Example 1.

[0096] Comparative Example 3

[0097] This embodiment is based on the embodiment 1, and the evaporation method in step 4 is adjusted, and the graded evaporation is no longer used. Specifically:

[0098] Step 4: Evaporate the reaction liquid in the reactor at 140°C for 40 min, and condense the evaporated gas by using a first-level water cooling at 40°C and a second-level deep cooling at 10°C. Collect the condensate for later use, and spray the condensed tail gas with 10% NaOH solution for absorption and activated carbon adsorption.

[0099] The remaining steps and conditions are the same as those in Example 1.

[0100] 1500L containing Br - Taking bromine-containing brine with a concentration of 55 g / L as an example, the steps and methods recorded in the above examples and comparative examples were used to purify bromine, and the consumption of Cl2 in the oxidation stage, the amount and purity of bromine obtained by condensing the blown gas, and the amount and purity of bromine obtained by the final distillation were recorded in each example and comparative example. The recorded data are as follows:

[0101]

[0102] According to the above data, we can know that:

[0103] In Example 2, the pH of step 1 was adjusted from 1.5 to 2.0, and the temperature was lowered from 45°C to 40°C. The weakening of the acidity resulted in a decrease in the oxidation reaction rate, requiring more Cl2 to complete the reaction. At the same time, the effect of high temperature on inhibiting the hydrolysis of Br2 was weakened, and some Br2 was lost, resulting in a decrease in the amount and purity of condensed bromine.

[0104] In Example 3, the ratio of CO2 to Cl2 is adjusted to 1:5, the CO2 ratio is reduced, and the Cl2 concentration is increased. During the reaction process, excessively high local Cl2 concentration will produce side reactions, thereby reducing the utilization rate of Cl2 and increasing its consumption. In addition, the side reactions will cause a small amount of Br2 to decompose due to local overheating, resulting in a slight decrease in the amount and purity of condensed bromine.

[0105] In Example 4, the primary water cooling temperature is increased to 50° C., resulting in a decrease in condensation efficiency and incomplete liquefaction of some Br2. In addition, at high temperatures, Br2 is more likely to remain in the gas phase, further reducing the recovery rate.

[0106] In Example 5, the temperature of the distillation tower bottom is lowered, resulting in a decrease in the separation efficiency of xylene and Br2, and some Br2 remains in the liquid phase. However, since the top temperature is close to the boiling point of Br2, the purity is less affected.

[0107] In Comparative Example 1, no CO2 was added, resulting in Cl2 directly reacting with Br - The concentration during the reaction is too high, the reaction is violent and the side reactions increase. Br2 is partially decomposed due to local overheating, the Cl2 consumption increases significantly, and the amount and purity of condensed bromine decrease significantly.

[0108] In Comparative Example 2, graded condensation is cancelled and 10°C deep cooling is directly adopted. The Br2 concentration in the gas that has not undergone the first-level water cooling pretreatment is too high, resulting in an excessively large deep cooling load. Some Br2 is not completely captured, thereby reducing the amount of condensed bromine and reducing the condensation purity due to residual impurities.

[0109] In Comparative Example 3, the graded evaporation was cancelled and evaporation at 140°C was directly adopted. The high temperature caused thermal decomposition of part of the Br2 and uneven evaporation, which increased the amount of residual bromine. As a result, the final distilled bromine amount was reduced, and the purity was slightly lower because the impurities were not removed in stages.

[0110] While the embodiments of the present invention are described above, these embodiments do not exhaustively describe all details, nor do they limit the present invention to only specific embodiments. Clearly, many modifications and variations can be made based on the above description. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to make good use of the present invention and its modifications and uses. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A vaporization process for preparing high-purity bromine, characterized in that: The following steps are involved: Step 1, raw material pretreatment: dilute the bromine-containing raw material and adjust it to an acidic environment to obtain a reaction stock solution; Step 2, oxidation reaction: heating the reaction solution to 60°C to 90°C, introducing a mixture of carbon dioxide and chlorine at a volume ratio of 1:3 to 5 to react and generate gaseous bromine. The reaction is terminated when the bromide ion concentration in the reaction solution is lower than 0.1 g / L; Step 3, blowing and collecting: introducing carrier gas into the reaction system, blowing out the gaseous bromine and recovering it through multi-stage condensation, while treating the tail gas; Step 4, vaporization collection: the reaction liquid is subjected to primary evaporation and secondary evaporation, and the primary evaporation is connected in parallel with the secondary evaporation in series, the residual bromine is evaporated and recovered by primary water cooling and secondary cryogenic condensation, and the primary water cooling is connected in parallel with the secondary cryogenic in series; Step 5, extraction and separation: the bromine solution recovered by condensation is mixed with an organic solvent for extraction, and the organic phase is separated; Step 6, distillation and purification: distill the organic phase to separate high-purity bromine and recover the solvent.

2. The vaporization process for preparing high-purity bromine according to claim 1, characterized in that: In step 1, the bromine-containing raw material is bromine-containing brine or bromine salt solution, the bromide ion concentration in the diluted solution is 20g / L~45g / L, the pH is adjusted to 0.5~2.0, the reaction temperature is 40℃~50℃, and the reaction time is 20~30 minutes.

3. The vaporization process for preparing high-purity bromine according to claim 1, characterized in that: In step 5, the organic solvent is xylene, and the volume ratio of xylene to the bromine solution is 2-3:1-2.

4. The vaporization process for preparing high-purity bromine according to claim 1, characterized in that: In step 6, the distillation conditions include: tower bottom temperature 120° C. to 140° C., tower top temperature 50° C. to 58° C., tower internal pressure 80 kPa to 100 kPa, and reflux ratio 2 to 4:

1.

5. The vaporization process for preparing high-purity bromine according to claim 1, characterized in that: In step 3, the tail gas is treated in sequence through an alkaline spray tower and an activated carbon adsorption tower, and the alkaline solution in the alkaline spray tower is an 8% to 15% NaOH solution.

6. The vaporization process for preparing high-purity bromine according to claim 1, characterized in that: The temperature of the first-level water cooling is 30°C to 50°C, and the temperature of the second-level deep cooling is 5°C to 10°C.

7. The vaporization process for preparing high-purity bromine according to claim 1, characterized in that: The temperature of the first-stage evaporation is 70°C to 90°C, and the temperature of the second-stage evaporation is 120°C to 150°C.

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