Phenol content determination device and method

Abstract

The invention belongs to the technical field of phenol determination, discloses a phenol content determination device and a phenol content determination method, and is used for solving the problems of complicated operation and large error of a traditional bromination volumetric method during high-concentration phenol determination. The device is composed of a plurality of one-way pumps, a two-way pump, a three-way pipe, a switch valve, a stirring unit and an ultrasonic cleaning machine, and automatic dilution and reaction are achieved through modular pipeline design. During use, a mixed solution of KBrO3-KBr and phenol, 1: 1 hydrochloric acid and distilled water are pumped into the system and react with a KI solution after online dilution, and determination is completed through circular stirring and titration. The device adopts a polytetrafluoroethylene pipeline, and magnetic stirring and ultrasonic cleaning assistance are combined, so that sufficient reaction is ensured. The method does not need to be diluted in advance, can directly measure a high-concentration phenol sample with the concentration of 100-1000 mg / L, has the advantages of being easy and convenient to operate, accurate in result and the like, and is suitable for high-concentration phenol measurement.

Description

Technical Field

[0001] The present invention relates to the technical field of phenol determination, and in particular to a device and method for determining phenol content. Background Art

[0002] The commonly used quantitative analysis method for determining phenol content at this stage is the "Bromide Volumetric Method for Determination of Volatile Phenols in Water." However, the detection range of the bromination volumetric method is only 0.4 to 45 mg / L. When measuring unknown high concentrations of phenol (100 to 1000 mg / L), multiple preliminary experiments are often required to determine the dilution factor before performing the dilution measurement. This makes the operation cumbersome, increases the experimental error, and often cannot achieve rapid response and accurate measurement. Therefore, in response to the above-mentioned shortcomings, the present invention proposes a phenol content determination device. Under the premise of not changing the reaction principle, it adopts the advantages of flow state modularization, closed design, and automation, and can directly and accurately determine high concentrations of phenol. Summary of the Invention

[0003] The present invention aims to provide a device and method for determining phenol content, so as to solve the problem of complicated operation process when determining unknown high concentration of phenol in the prior art.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] A phenol content measuring device includes a first one-way pump, one end of the first one-way pump is connected to a first tee, and the other end is used to input a KBrO3-KBr and phenol mixed solution, the first tee is also connected to a second tee and a second one-way pump, one end of the second one-way pump is connected to the first tee, and the other end is used to input a 1:1 hydrochloric acid solution, the second tee is also connected to a third tee and a fourth tee, the other two ends of the third tee are respectively connected to the third one-way pump and the first switch valve, the third one-way pump is used to input distilled water, a stirring unit is provided between the third and fourth tees, the stirring unit includes a magnetic stirrer, a magnet and a quartz glass tube, and the pipeline between the third and fourth tees is connected to the first tee. A first tube coil is formed and placed in an ultrasonic cleaning machine. The fourth tee is further connected to a fourth unidirectional pump and a fifth tee. The fourth unidirectional pump is used to input KI solution. A second switch valve is provided between the fourth and fifth tees. The fifth tee is further connected to a bidirectional pump and a sixth tee. A third switch valve is provided between the fifth tee and the bidirectional pump. The other end of the bidirectional pump is connected to the sixth tee. A stirring unit is provided between the fifth and sixth tees. The pipeline between the fifth and sixth tees forms a second tube coil and is placed in an ultrasonic cleaning machine. The last end of the sixth tee is connected to the outside for outputting the final product, and the pipeline at the last end is provided with a fourth switch valve and a stirring unit.

[0006] Furthermore, the connecting pipes between the components are 3*4mm polytetrafluoroethylene pipes, the volume inside the first tube tray is 15ml, and the volume inside the second tube tray is 70ml.

[0007] A method for using a phenol content measuring device comprises the following steps:

[0008] S1. In the initial state, ensure that the first switch valve is closed, the second, third, and fourth switch valves are open, the pumps are closed, and the stirring unit and ultrasonic cleaning machine are always in the open state;

[0009] S2. Turn on the first one-way pump and the second one-way pump to input the KBrO3-KBr and phenol mixed solution and the 1:1 hydrochloric acid solution respectively, so that the solutions mix and meet in the first three-way pipe. At the same time, turn on the third one-way pump to input distilled water, so that the solutions are mixed and diluted in the second three-way pipe and pass through the stirring unit;

[0010] S3. When the mixed solution passes through the first tube coil and reaches the fourth three-way pipe, the fourth one-way pump is turned on to input the KI solution so that the KI solution and the mixed solution are completely mixed;

[0011] S4. When the mixed solution flows through the second on-off valve into the second pipe coil and is about to reach the fourth on-off valve, the fourth and second on-off valves and all pumps are closed in sequence. The first on-off valve is opened and immediately closed, and then the bidirectional pump is opened to start circulation in the pipeline. The solution flows from the bidirectional pump into the fifth tee pipe, which is forward rotation.

[0012] S5. When the precipitate in the circulation system is finely divided and not wrapped with precipitate, the bidirectional pump is reversed, the fifth three-way pipe flows into the bidirectional pump, and the fourth on-off valve, the fourth one-way pump, the second on-off valve, and the third one-way pump are opened in sequence, so that the solution and precipitate enter the stirring unit and are discharged to obtain the final product;

[0013] S6. When there is no color in the pipeline, take out the discharge liquid and place it in a starch indicator solution containing KI to observe whether it turns blue. If it turns blue, there is still bromine or iodine residue in the pipeline, and the third one-way pump needs to be operated to clean it. If there is no color change, turn off all instruments and perform titration.

[0014] Furthermore, the first one-way pump inputs 20 ml of a 1:1 mixed solution of KBrO3-KBr and phenol, the second one-way pump inputs 13 ml of a 1:1 hydrochloric acid solution, and the fourth one-way pump inputs 25 ml of a 10% KI solution.

[0015] Furthermore, in step S2, the flow rates of the first unidirectional pump and the second unidirectional pump are controlled to be 30 ml / min and 15 ml / min respectively, and in step 3, the flow rate of the fourth unidirectional pump is controlled to be 15 ml / min.

[0016] The principles and beneficial effects of this technical solution: The device of the present invention transforms cumbersome measurement steps into semi-automated ones. The dilution step of the device effectively reduces the generation of precipitation per unit volume and reduces precipitation wrapping. The device of the present invention avoids cumbersome experimental operations and only requires the control of a pump and an on-off valve to complete the dilution measurement. The closed channel effectively prevents the volatilization of bromine gas, effectively reducing the error in phenol measurement. At the same time, the device of the present invention allows intuitive observation of experimental phenomena. The device of the present invention can directly and quickly measure high-concentration phenol, which can meet the needs of phenol measurement over a wide range of high concentrations. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the connection of various components of the device of the present invention;

[0018] Figure 2 This is a schematic structural diagram of the stirring unit of the device of the present invention;

[0019] In the figure: 11. First one-way pump; 12. Second one-way pump; 13. Third one-way pump; 14. Fourth one-way pump; 21. First three-way pipe; 22. Second three-way pipe; 23. Third three-way pipe; 24. Fourth three-way pipe; 25. Fifth three-way pipe; 26. Sixth three-way pipe; 31. First on-off valve; 32. Second on-off valve; 33. Third on-off valve; 34. Fourth on-off valve; 4. Stirring unit; 41. Magnetic stirrer; 42. Magnet; 43. Quartz glass tube; 51. First tube reel; 52. Second tube reel; 6. Ultrasonic cleaning machine; 7. Two-way pump. DETAILED DESCRIPTION

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0021] like Figure 1 、 2The device for measuring phenol content shown in the figure includes a first one-way pump 11. The input end of the first one-way pump 11 is used to input a mixed solution of KBrO3-KBr and phenol. The output end of the first one-way pump 11 is connected to a first three-way pipe 21. The other two ends of the first three-way pipe 21 are respectively connected to a second one-way pump 12 and a second three-way pipe 22. The input end of the second one-way pump 12 is used to input a 1:1 hydrochloric acid solution. The output end of the second one-way pump 12 outputs the 1:1 hydrochloric acid solution to the first three-way pipe 21. The other two ends of the second three-way pipe 22 are respectively connected to a third three-way pipe 23. The other two ends of the third three-way pipe 23 are connected to the outside at one end and to the third one-way pump 13 at the other end. The third one-way pump 13 is used to input distilled water. The pipeline connecting the third three-way pipe 23 and the outside is provided with a first switch valve 31. The pipeline between the second three-way pipe 22 and the fourth three-way pipe 24 is provided with a stirring unit 4. The stirring unit 4 includes a magnetic stirrer 41, a magnet 42 and a quartz glass tube 43. The pipeline between the second three-way pipe 22 and the fourth three-way pipe 24 is coiled to form a first pipe disc 51. The first pipe disc 51 is located at the ultrasonic In the cleaning machine 6, the other two ends of the fourth three-way pipe 24 are respectively connected to the fourth one-way pump 14 and the fifth three-way pipe 25. The fourth one-way pump 14 is used to input KI solution. A second switch valve 32 is provided between the fourth three-way pipe 24 and the fifth three-way pipe 25. The two ends of the fifth three-way pipe 25 are connected to the sixth three-way pipe 26 and the two-way pump 7. A third switch valve 33 is provided between the fifth three-way pipe 25 and the two-way pump 7. The two ends of the two-way pump 7 are connected to the fifth three-way pipe 25 and the sixth three-way pipe 26. It is stipulated that the flow of the fifth three-way pipe 25 to the two-way pump 7 is forward rotation, and the flow of the two-way pump 7 to the fifth three-way pipe is forward rotation. 25 is a reversal, a stirring unit 4 is provided between the fifth tee 25 and the sixth tee 26, the pipe between the fifth tee 25 and the sixth tee 26 is twisted to form a second pipe disc 52, and the second pipe disc 52 is also located in the ultrasonic cleaning machine 6. The last end of the sixth tee 26 is used to output the final product, and the pipe at the last end is provided with a fourth switch valve 34 and a stirring unit 4. The pipes connecting the various components are 3*4mm polytetrafluoroethylene pipes, and the volume inside the first pipe disc 51 is 15ml, and the volume inside the second pipe disc 52 is 70ml.

[0022] The specific implementation process is as follows: 1. Before starting, ensure that the first switch valve is in the closed state, the second, third, and fourth switch valves are all in the open state, the pumps are all in the closed state, and the stirring unit and ultrasonic cleaning machine are always in the open state;

[0023] 2. Turn on the first and second one-way pumps, and respectively input 20 ml of a 1:1 mixture of KBrO3-KBr and phenol and 13 ml of a 1:1 hydrochloric acid solution. The flow rates of the two pumps are controlled at 30 ml / min and 15 ml / min, respectively, so that the solutions meet and mix in the first tee. Simultaneously, turn on the third one-way pump to pump water and input distilled water, so that the three are mixed and diluted in the third tee, and then stirred by the stirring unit.

[0024] 3. When the mixed solution passes through the first tube tray and reaches the fourth tee, open the fourth tee and inject 25 ml of 10% KI solution at a flow rate of 15 ml / min to mix the KI solution with the mixed solution.

[0025] 4. When the mixed solution flows through the second switch valve into the second pipe coil and is about to reach the fourth switch valve, close the fourth and second switch valves and all pumps in sequence, open the first switch valve and then close it immediately, then open the two-way pump to start circulation in the pipeline;

[0026] 5. When the precipitate in the circulation system is finely divided and there is no precipitate wrapping, reverse the bidirectional pump, open the fourth switch valve, the fourth one-way pump, the second switch valve and the third one-way pump in sequence, so that the solution and precipitate are discharged through the stirring unit to obtain the final product;

[0027] 6. When there is no obvious color in the pipeline, take the discharge liquid and place it in a starch indicator solution containing KI to observe whether it turns blue. If it turns blue, there is still bromine or iodine residue in the pipeline, and it is necessary to continue to operate the third one-way pump for cleaning; if there is no color change, all instruments can be turned off and then titration determination can be performed.

[0028] The above is only an embodiment of the present invention, and common knowledge such as the specific technical solutions or characteristics in the solution is not described in detail here. For those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the description can be used to interpret the content of the claims.

Claims

1. A phenol content measuring device, characterized in that: The invention comprises a first one-way pump (11), one end of the first one-way pump (11) is connected to a first three-way pipe (21), and the other end is used to input a KBrO3-KBr and phenol mixed solution, the first three-way pipe (21) is also connected to a second three-way pipe (22) and a second one-way pump (12), one end of the second one-way pump (12) is connected to the first three-way pipe (21), and the other end is used to input a 1:1 hydrochloric acid solution, the second three-way pipe (22) is also connected to a third three-way pipe (23) and a fourth three-way pipe (24). ), the other two ends of the third three-way pipe (23) are respectively connected to a third one-way pump (13) and a first switch valve (31), the third one-way pump (13) is used to input distilled water, a stirring unit (4) is provided between the third three-way pipe (23) and the fourth three-way pipe (24), the stirring unit (4) includes a magnetic stirrer (41), a magnet (42) and a quartz glass tube (43), the pipeline between the third three-way pipe (23) and the fourth three-way pipe (24) forms a first pipe disc (51) and Placed in an ultrasonic cleaning machine (6), the fourth three-way pipe (24) is further connected to a fourth one-way pump (14) and a fifth three-way pipe (25), the fourth one-way pump (14) is used to input KI solution, a second switch valve (32) is provided between the fourth three-way pipe (24) and the fifth three-way pipe (25), the fifth three-way pipe (25) is further connected to a two-way pump (7) and a sixth three-way pipe (26), a third switch valve (33) is provided between the fifth three-way pipe (25) and the two-way pump (7), The other end of the bidirectional pump (7) is connected to the sixth tee (26); a stirring unit (4) is provided between the fifth tee (25) and the sixth tee (26); the pipeline between the fifth tee (25) and the sixth tee (26) forms a second pipe disc (52) and is placed in the ultrasonic cleaning machine (6); the last end of the sixth tee (26) is connected to the outside for outputting the final product, and a fourth switch valve (34) and a stirring unit (4) are provided on the pipeline at the last end.

2. A phenol content measuring device according to claim 1, characterized in that: The connecting pipes between the components are 3*4mm polytetrafluoroethylene pipes. The volume inside the first tube tray is 15ml, and the volume inside the second tube tray is 70ml.

3. A method for using a phenol content measuring device according to any one of claims 1-2, characterized in that: The following steps are involved: S1. In the initial state, ensure that the first switch valve is closed, the second, third, and fourth switch valves are open, the pumps are closed, and the stirring unit and ultrasonic cleaning machine are always in the open state; S2. Turn on the first one-way pump and the second one-way pump to input the KBrO3-KBr and phenol mixed solution and the 1:1 hydrochloric acid solution respectively, so that the solutions mix and meet in the first three-way pipe. At the same time, turn on the third one-way pump to input distilled water, so that the solutions are mixed and diluted in the second three-way pipe and pass through the stirring unit; S3. When the mixed solution passes through the first tube coil and reaches the fourth three-way pipe, the fourth one-way pump is turned on to input the KI solution so that the KI solution and the mixed solution are completely mixed; S4. When the mixed solution flows through the second on-off valve into the second pipe coil and is about to reach the fourth on-off valve, the fourth and second on-off valves and all pumps are closed in sequence. The first on-off valve is opened and immediately closed, and then the bidirectional pump is opened to start positive circulation in the pipeline. The solution flows from the bidirectional pump into the fifth tee pipe, which is positive circulation. S5. When the precipitate in the circulation system is finely divided and not wrapped with precipitate, the bidirectional pump is reversed, and the solution flows into the bidirectional pump through the fifth three-way pipe. The fourth on-off valve, the fourth one-way pump, the second on-off valve, and the third one-way pump are opened in sequence, so that the solution and precipitate enter the stirring unit and are discharged to obtain the final product; S6. When there is no color in the pipeline, take out the discharge liquid and place it in a starch indicator solution containing KI to observe whether it turns blue. If it turns blue, there is still bromine or iodine residue in the pipeline, and the third one-way pump needs to be operated to clean it. If there is no color change, turn off all instruments and perform titration.

4. The method for using the phenol content measuring device according to claim 3, wherein: The first one-way pump inputs 20 ml of a 1:1 mixed solution of KBrO3-KBr and phenol, the second one-way pump inputs 13 ml of a 1:1 hydrochloric acid solution, and the fourth one-way pump inputs 25 ml of a 10% KI solution.

5. The method for using the phenol content measuring device according to claim 3, wherein: In step S2, the flow rates of the first and second unidirectional pumps are controlled to be 30 ml / min and 15 ml / min respectively, and in step 3, the flow rate of the fourth unidirectional pump is controlled to be 15 ml / min.

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