Liquid bromine adsorption quantity measuring device

Abstract

A liquid bromine adsorption quantity measuring device comprises an adsorption device, a liquid bromine storage bottle, an adsorbent placing bottle, a heating coil, a heating control device and an adsorption tube, a first opening in the adsorption tube is connected with the adsorbent placing bottle, a second opening is communicated with the liquid bromine storage bottle, and a third opening is connected with the vacuum pump; a first valve is arranged between the first opening and the second opening, and a second valve is arranged between the first opening and the third opening; the heating coil is wound outside the adsorbent placing bottle and is connected with the heating control device; the desorption device comprises a desorption pipe, a vacuum flask and a Dewar flask; a middle opening of the desorption pipe is communicated with the adsorbent placing bottle, one end of the desorption pipe is provided with a desorption pipe suction port connected with the vacuum pump, the other end of the desorption pipe is communicated with the vacuum bottle, and a third valve is arranged between the desorption pipe suction port and the middle opening of the desorption pipe; a heating coil is wound outside the adsorbent placing bottle; and the vacuum flask is placed in the liquid nitrogen of the Dewar flask. The device can accurately measure the adsorption capacity of the bromine adsorbent.

Description

Technical Field

[0001] This invention belongs to the field of liquid bromine adsorption technology, specifically relating to a liquid bromine adsorption capacity measuring device. Background Technology

[0002] Bromine (Br) is a chemical element with atomic number 35, located in period 4 and group VIIA of the periodic table, and is one of the halogen elements. Bromine molecules are volatile, reddish-black liquids at standard temperature and pressure, but can solidify into bluish-black solids at low temperatures. Its reactivity is between that of chlorine and iodine. Bromine is a relatively reactive nonmetallic element, usually existing in molecular form, Br₂, and pure bromine is also called bromine. Liquid bromine is corrosive and toxic. Bromine and its compounds are used as flame retardants, water purifiers, pesticides, dyes, etc. Bromine is relatively rare in nature, mainly existing in the form of salt water, seawater, and some minerals. Bromine compounds are also used as flame retardants to help slow down the burning rate of objects and improve fire safety.

[0003] In industrial wastewater treatment, some chemical companies generate bromine-containing wastewater during production. If the bromine in this wastewater cannot be effectively adsorbed, it will be directly discharged into the soil, increasing pollution to the natural environment and raising the risk of acid rain. In industrial wastewater treatment, if bromide ions in the water cannot be adsorbed, bromine-containing wastewater will pollute surface water, soil, and groundwater, damaging aquatic ecosystems. Furthermore, in some experimental environments involving bromine or in bromine storage sites, adsorption devices can serve as safety protection equipment to adsorb potentially leaked bromine, reducing the risk of operator exposure and ensuring personnel safety.

[0004] Whether for industrial wastewater treatment or safety protection devices in special locations, using bromine adsorbents is an effective treatment or protection measure. However, when selecting a bromine adsorbent, it is necessary to clarify the adsorbent's adsorption capacity for bromine. Therefore, accurately measuring the adsorbent's adsorption capacity for bromine is crucial. Utility Model Content

[0005] The purpose of this invention is to provide a liquid bromine adsorption capacity measuring device. This device uses a set of experimental apparatus to determine the adsorption capacity of bromine adsorbents through adsorption, desorption, and titration of liquid bromine, providing experimental basis for the selection of adsorbents.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a liquid bromine adsorption capacity measuring device, used for sampling in the determination of liquid bromine adsorption capacity, comprising an adsorption device for adsorbing bromine evaporated from liquid bromine through an adsorbent; the adsorption device includes a liquid bromine storage bottle, an adsorbent placement bottle, a heating coil, a heating control device, and an adsorption tube; the adsorption tube is provided with a first opening, a second opening, and a third opening, the first opening being connected to the mouth of the adsorbent placement bottle, the second opening and the third opening being located at both ends of the adsorption tube, the second opening being used to communicate with the liquid bromine storage bottle, and the third opening being used to connect with a vacuum pump; the adsorption tube is also provided with a first valve and a second valve, the first valve being located between the first opening and the second opening, and the second valve being located between the first opening and the third opening; the heating coil is wound around the outside of the adsorbent placement bottle, and the heating control device is connected to the heating coil for controlling the heating and temperature setting of the heating coil;

[0007] It also includes a desorption device, which uses heating to cause the adsorbent in the adsorbent placement bottle to desorb the adsorbed bromine and collect it for titration measurement; the desorption device includes a desorption tube, a thermos flask, and a Dewar flask; the middle opening of the desorption tube is used to communicate with the mouth of the adsorbent placement bottle, one end of the desorption tube is provided with a desorption tube suction port for connection to a vacuum pump, and the other end is used to communicate with the thermos flask, and a third valve is provided between the desorption tube suction port and the middle opening of the desorption tube; the heating coil is wound around the outside of the adsorbent placement bottle, and the heating coil is connected to the heating control device; the thermos flask is placed in liquid nitrogen in the Dewar flask.

[0008] In the adsorption device, the adsorption tube and the liquid bromine storage bottle are connected by a PTFE stopper. The PTFE stopper has a channel, one end of which is connected to the second opening of the adsorption tube, and the other end of which is connected to the liquid bromine storage bottle.

[0009] In the adsorption device, the inner wall of the liquid bromine storage bottle is provided with an anti-corrosion coating.

[0010] The adsorbent placement bottle is wrapped with tin foil, and the heating coil is wound on the tin foil.

[0011] In the desorption device, the desorption tube is connected to the thermos bottle through a U-shaped tube and a vertical tube. The U-shaped tube is connected to the desorption tube, and the vertical tube is connected to the thermos bottle.

[0012] The U-shaped tube includes a U-shaped pipe section and a straight pipe section, both of which are integrally formed. The end of the straight pipe is connected to an opening on one side of the vertical pipe, and the beginning of the U-shaped tube is connected to an opening at the bottom of the desorption tube.

[0013] The straight pipe is arranged parallel to the desorption pipe and is located below the desorption pipe.

[0014] The upper end of the vertical tube is provided with a PTFE plug, which is used to seal the opening on the side of the vertical tube after the analysis is completed.

[0015] The beneficial effects of this invention are as follows: This invention achieves sampling of the adsorption amount of the adsorbent through the adsorption and desorption of liquid bromine, so that the liquid bromine obtained after desorption can be titrated using the indirect iodometric method to determine the amount of liquid bromine, thereby determining the adsorption capacity of the adsorbent for bromine, realizing the determination of the adsorption amount of bromine adsorbent, which can be used for the evaluation and selection of the adsorption capacity of different bromine adsorbents, and providing data support for the adsorption treatment of liquid bromine.

[0016] The entire adsorption and desorption process of this invention is carried out in a relatively closed environment, ensuring the safety of the test process and the reliability of the measurement results. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the liquid bromine adsorption device in Example 1;

[0019] Figure 2 This is a schematic diagram of the liquid bromine desorption device in Example 1;

[0020] Figure 3 This is a schematic diagram of the liquid bromine titration process in Example 1;

[0021] The diagram is labeled as follows: 1. Tetrafluoroethylene stopper, 2. Liquid bromine storage bottle, 201. Anti-corrosion coating, 3. Liquid bromine, 4. Adsorbent placement bottle, 5. Heating coil, 6. Adsorbent, 7. Heating control device, 701. Actual temperature display screen, 702. Set temperature display screen, 8. Adsorption tube, 9. First valve, 10. Second valve, 11. Third opening, 12. Desorption tube, Third valve, 14. Desorption tube suction port, 15. Thermos bottle, 16. Liquid nitrogen, 17. Dewar flask, 1801. U-shaped pipe, 1802. Straight pipe, 19. KI molten liquid bottle, 20. Ammonium thiosulfate solution bottle, 21. Vertical pipe. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention in any way.

[0023] Example 1: A liquid bromine adsorption capacity measuring device, comprising an adsorption device and a desorption device. The adsorption device is used to adsorb bromine volatilized from liquid bromine by an adsorbent. The desorption device causes the adsorbent to desorb the adsorbed bromine by heating and collects it so as to titrate the released bromine to obtain a sample that can be titrated, and then the adsorption capacity of the adsorbent for bromine is obtained after titration.

[0024] like Figure 1 As shown, the adsorption device includes a tetrafluoroethylene stopper 1, a liquid bromine storage bottle 2, an adsorbent placement bottle 4, a heating coil 5, a heating control device 7, and an adsorption tube 8. The adsorption tube 8 has a first opening in its middle, which connects to the mouth of the adsorbent placement bottle 4. The two ends of the adsorption tube 8 have a second opening and a third opening 11, respectively. The second opening communicates with the mouth of the liquid bromine storage bottle 2 through the tetrafluoroethylene stopper 1, and the third opening 11 is used to connect to a vacuum pump. A first valve 9 is provided between the first and second openings, and a second valve 10 is provided between the first opening and the third opening 11. The heating coil 5 is located outside the adsorbent placement bottle 4 and is wound around the lower part of the adsorbent placement bottle 4. The heating coil 5 is connected to the heating control device 6, which controls the on / off state of the heating coil 5 and adjusts the heating temperature.

[0025] The liquid bromine storage bottle 2 is a brown glass bottle with an anti-corrosion coating 201 attached to the inner wall of the glass bottle to separate the glass substrate from the liquid bromine 3 and prevent the liquid bromine from directly contacting the inside of the glass bottle and causing a corrosion reaction.

[0026] The adsorbent placement bottle 4 is a ceramic bottle containing adsorbent 6 for adsorption. The bottle is wrapped with tin foil, and the heating coil 5 is wound around the tin foil. This reduces heat dissipation from electromagnetic heating and increases the heating rate within the device. It also prevents the adsorbent 6 and liquid bromine from being directly exposed to light, which could cause changes in the adsorption performance of the adsorbent 6 or desorption of liquid bromine from the adsorbent 6.

[0027] Both the adsorption tube 8 and the PTFE stopper 1 are made of Teflon material, which effectively prevents liquid bromine from evaporating into the atmosphere and causing environmental pollution. Teflon also has the characteristics of being resistant to acids, alkalis, and organic solvents; it is almost insoluble in common laboratory solvents and can withstand high temperatures, ensuring stability under high-temperature conditions. The liquid bromine storage bottle 2 has a ground glass joint, which can be tightly connected to the PTFE stopper 1, ensuring good airtightness of the device and preventing liquid bromine evaporation.

[0028] The first valve 9 and the second valve 10 are connected to the adsorption tube 8 by a threaded connection. The adsorption tube 8 is provided with an external thread, and the valve is provided with an internal thread. When the internal and external threads are connected, a sealing material is also applied to enhance the airtightness of the connection and prevent liquid bromine leakage.

[0029] In practice, liquid bromine is placed in liquid bromine storage bottle 2, and adsorbent 6 is placed in adsorbent placement bottle 4. The two valves on the adsorption tube 8 are opened, and a vacuum pump is used to evacuate the system to a vacuum state or near-vacuum state through the third opening 11 of the adsorption tube 8. Then, the second valve 10 is closed, and the heating control device 7 is turned on and adjusted to the optimal adsorption temperature of the adsorbent 6. The liquid bromine in the liquid bromine storage bottle 2 evaporates and diffuses, filling the device with reddish-brown bromine vapor. The bromine vapor diffuses to the adsorbent placement bottle 4 and is adsorbed by the adsorbent 6. This process is time-consuming, and the heating coil 5 needs to be kept heated during this process. After the set test time (e.g., 48 hours) is reached, the heating control device 7 is turned off. Once the system temperature has cooled to room temperature, the adsorbent placement bottle 4 can be removed and the stopper closed.

[0030] like Figure 2 As shown, the desorption device includes a desorption tube 12, an adsorbent placement bottle 4, a thermos flask 15, a Dewar flask 17, a heating coil 4, and a heating control device 7.

[0031] The desorption tube 12 has a central opening for connecting to the mouth of the adsorbent placement bottle 4. A desorption tube suction port 14 is provided at the first end of the desorption tube 12 for connecting to a suction device, such as a vacuum pump. A third valve 13 is provided between the desorption tube suction port 14 and the central opening of the desorption tube 12. A U-shaped tube is connected in parallel to the second end of the desorption tube 12, and both the opening of the second end and the opening of the U-shaped tube are connected to a vertical tube 21. The lower end of the vertical tube 21 is connected to the mouth of the thermos flask 15. The opening at the second end of the desorption tube 12 is sealed with a PTFE stopper 1. During desorption, the lower end of the PTFE stopper 1 is higher than the position where the U-shaped tube connects to the vertical tube 21, allowing the desorbed bromine vapor to enter the vertical tube 21 through the U-shaped tube and then into the thermos flask 15. After desorption is complete, the PTFE stopper 1 is inserted downwards to seal the opening on the vertical tube 21 that connects to the U-shaped tube. In the desorption device, the PTFE plug 1 used differs in structure from that in the adsorption device. The PTFE plug 1 in the desorption device primarily serves a sealing function and does not require internal channels. The desorption tube 12, like the adsorption tube 8, is made of Teflon material.

[0032] Preferably, the second end of the desorption tube 12 does not need to be provided with an opening. In this way, it is only necessary to insert the PTFE stopper 1 into the upper end of the vertical tube 21. When the thermos bottle 15 needs to be removed after desorption, the insertion depth of the PTFE stopper 1 is increased to block the opening on the vertical tube 21 that communicates with the U-shaped tube.

[0033] The U-shaped tube comprises an integrally formed U-shaped pipe 1801 and a straight pipe 1802. The end of the straight pipe 1802 is connected to an opening on one side of the vertical pipe 21, and the end of the U-shaped pipe 1801 is connected to an opening at the bottom of the desorption pipe 12. The straight pipe 1802 is arranged parallel to the desorption pipe 12 and is located below the desorption pipe 12. Using the U-shaped tube can promote the full condensation of bromine vapor and prevent backflow of liquid bromine when the system pressure changes.

[0034] The thermos flask 15 is placed in the liquid nitrogen 16 of the Dewar flask 17. The liquid nitrogen 16 creates a low-temperature environment, which causes the bromine vapor entering the thermos flask 15 to condense into liquid bromine and be stored inside the thermos flask 15.

[0035] In the desorption device, the adsorbent placement bottle 4 is the same as the adsorbent placement bottle 4 used in the adsorption process. The adsorbent 6 inside the bottle adsorbs bromine. A heating coil 5 is wound around the outside of the adsorbent placement bottle 4, and the heating coil 5 is connected to a heating control device 7. During desorption, the heating temperature is adjusted to 200°C by the heating control device 7. At this temperature, the bromine in the adsorbent 6 is desorbed and becomes bromine vapor.

[0036] The specific desorption process is as follows: According to Figure 2 Connect the desorption device, open the third valve 13, evacuate the system using the vacuum pump, then close the third valve 13 and turn on the heating control device 7 to set the temperature to 200°C. o C. Adsorbent 6 will desorb the adsorbed liquid bromine, and the bromine vapor will enter the thermos flask 15. At this time, the ultra-low temperature conditions provided by liquid nitrogen 16 will stably preserve the liquid bromine in the thermos flask 15. Maintain this process for more than 8 hours, then tightly plug the PTFE stopper 1 downwards to seal the outlet of the U-shaped tube. Then, remove the thermos flask 15, tightly plug the mouth of the flask, and thaw it to room temperature to prepare for the next titration process.

[0037] In the titration process, the indirect iodometric method is used, where iodine is used as an oxidizing agent or an iodide (such as potassium iodide) is used as a reducing agent to determine the content of a substance. Even trace amounts of iodine can immediately form a deep blue complex when it comes into contact with starch; the phenomenon is obvious, making the titration endpoint easy to find. The reaction is sensitive and can increase the accuracy of measuring bromine in the adsorbed solution.

[0038] like Figure 3As shown, during titration, an excess of 10% KI solution was added to the thermos flask to react fully with the liquid bromine. Then, 0.2000 mol / L sodium thiosulfate was added dropwise. Near the titration endpoint, a starch indicator (obtained by boiling 0.1 g of starch in 20 mL of water) was added, and titration continued until the endpoint. The timing of adding the starch indicator can be determined by the solution color; it can be added when the solution turns pale yellow. The phenomenon at the titration endpoint is that the blue color fades to colorless when the last drop of sodium thiosulfate solution is added, and the color remains unchanged for half a minute. The specific reaction process is represented by the following chemical equation: Br₂ + 2I₂ - =2Br - +I₂I₂+ 2S₂O₃ 2- =S4O6 2- +2I - Therefore, the ratio of the amount of adsorbed bromine to the amount of sodium thiosulfate is 1:2. Repeat this process two to three times and take the average value.

[0039] During titration, an excess of KI solution should be added to convert all the Br2 in the thermos flask into Br2. - This ensures the accuracy of the titration results. Because I₂ has low solubility in water, adding excess KI can form I₂. 3- To reduce I2 volatilization and increase I2 solubility, resulting in a higher I2 concentration in the solution, the following method can be used to ensure the addition of excess KI solution: Take 100-200 mg of the bromine-containing adsorbent, add a small amount of KI solution first. After completion, use photoelectric colorimetry to determine whether liquid bromine is present in the solution. If it is, it means the KI solution is not in excess, so continue adding dropwise until no liquid bromine is present. The amount of KI solution used at this point is the amount sufficient to fully react with the bromine in the adsorbent. Adding more KI solution to this amount constitutes an excess. Then, based on the mass of adsorbent used in the adsorption process, the amount of excess KI solution can be calculated.

[0040] The above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the specific implementation of this utility model with reference to the above embodiments. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this utility model are within the protection scope of the pending claims.

Claims

1. A liquid bromine adsorption capacity measuring device, used for sampling in the determination of liquid bromine adsorption capacity, characterized in that: The device includes an adsorption unit for adsorbing bromine evaporated from liquid bromine using an adsorbent. The adsorption unit comprises a liquid bromine storage bottle, an adsorbent placement bottle, a heating coil, a heating control device, and an adsorption tube. The adsorption tube has a first opening, a second opening, and a third opening. The first opening is connected to the mouth of the adsorbent placement bottle. The second and third openings are located at opposite ends of the adsorption tube. The second opening communicates with the liquid bromine storage bottle, and the third opening connects to a vacuum pump. The adsorption tube also has a first valve and a second valve. The first valve is located between the first and second openings, and the second valve is located between the first and third openings. The heating coil is wound around the outside of the adsorbent placement bottle. The heating control device is connected to the heating coil and controls the heating and temperature setting of the heating coil. It also includes a desorption device, which uses heating to cause the adsorbent in the adsorbent placement bottle to desorb the adsorbed bromine and collect it for titration measurement; the desorption device includes a desorption tube, a thermos flask, and a Dewar flask; the middle opening of the desorption tube is used to communicate with the mouth of the adsorbent placement bottle, one end of the desorption tube is provided with a desorption tube suction port for connection to a vacuum pump, and the other end is used to communicate with the thermos flask, and a third valve is provided between the desorption tube suction port and the middle opening of the desorption tube; the heating coil is wound around the outside of the adsorbent placement bottle, and the heating coil is connected to the heating control device; the thermos flask is placed in liquid nitrogen in the Dewar flask.

2. The liquid bromine adsorption capacity measuring device according to claim 1, characterized in that: In the adsorption device, the adsorption tube and the liquid bromine storage bottle are connected by a PTFE stopper. The PTFE stopper has a channel, one end of which is connected to the second opening of the adsorption tube, and the other end of which is connected to the liquid bromine storage bottle.

3. The liquid bromine adsorption capacity measuring device according to claim 1, characterized in that: In the adsorption device, the inner wall of the liquid bromine storage bottle is provided with an anti-corrosion coating.

4. The liquid bromine adsorption capacity measuring device according to claim 1, characterized in that: The adsorbent placement bottle is wrapped with tin foil, and the heating coil is wound on the tin foil.

5. The liquid bromine adsorption capacity measuring device according to claim 1, characterized in that: In the desorption device, the desorption tube is connected to the thermos bottle through a U-shaped tube and a vertical tube. The U-shaped tube is connected to the desorption tube, and the vertical tube is connected to the thermos bottle.

6. The liquid bromine adsorption capacity measuring device according to claim 5, characterized in that: The U-shaped tube includes a U-shaped pipe section and a straight pipe section, both of which are integrally formed. The end of the straight pipe is connected to an opening on one side of the vertical pipe, and the beginning of the U-shaped tube is connected to an opening at the bottom of the desorption tube.

7. The liquid bromine adsorption capacity measuring device according to claim 6, characterized in that: The straight pipe is arranged parallel to the desorption pipe and is located below the desorption pipe.

8. The liquid bromine adsorption capacity measuring device according to claim 6, characterized in that: The upper end of the vertical tube is provided with a PTFE plug, which is used to seal the opening on the side of the vertical tube after the analysis is completed.

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