Methods for determining color by titration and color titration apparatus

Abstract

This disclosure relates to a method and apparatus for determining the color of a titration. The method includes the following steps: manually titrating a standard titrant into the reagent required for the experiment and manually determining whether the reaction has reached its endpoint; obtaining the first solution color information at the endpoint of the reaction using a color titration apparatus to establish a standard value; conducting the experiment using the color titration apparatus, stopping the titration when the solution color information reaches the first solution color information, and recording the consumption value of the standard titrant. This disclosure first establishes a standard value manually, then compares the detection value of the color titration apparatus during the experiment with the manually established standard value, stopping the titration when the standard value is reached. This replaces manual determination of the endpoint of the color titration, is quick and labor-saving, and has high repeatability; it also avoids errors between instrument and manual determination results.

Description

Technical Field

[0001] This disclosure relates to the field of reagent testing technology, specifically to a method for determining color by titration and a color titration apparatus. Background Technology

[0002] Titration is a common method for quantitative detection. It determines the content of a solute by the quantitative reaction of two solutions. Most titration methods use the color change of an indicator to indicate the titration endpoint, and then calculate the volume of standard solution consumed and the analytical results.

[0003] Manual titration involves several steps: reading the initial value of the standard solution, titrating (while controlling the flow rate of the standard solution and continuously shaking), determining the endpoint, reading the endpoint value of the standard solution, and calculating the results. This process is cumbersome and requires significant effort when repeated, demanding a high level of skill from the operator. Currently, various titrators exist, which typically measure changes in ion concentration by measuring changes in electrode potential to control the reaction endpoint. Manual titration, however, relies on color changes to determine the endpoint. While instruments may define the endpoint as pH 7, the different indicators used in actual operation (which can change color over a pH range) introduce discrepancies between instrument and manual interpretation, leading to inaccurate test results. Summary of the Invention

[0004] The purpose of this disclosure is to provide a method and apparatus for determining color by titration, which can solve the above-mentioned technical problems.

[0005] To achieve the above objectives, this disclosure provides a method for determining the color of a titration, comprising the following steps: manually titrating a standard titrant into a reagent required for the experiment and manually determining whether the reaction has reached the endpoint; obtaining the first solution color information at the endpoint of the reaction using a color titration device to establish a standard value; conducting the experiment using the color titration device; stopping the titration when the solution color information reaches the first solution color information and recording the consumption value of the standard titrant.

[0006] Optionally, before the start of the test reaction, the reagent needs to be added to the titration cup, and the color information of the second solution before the start of the test reaction needs to be obtained by the color titration device.

[0007] Optionally, the first solution color information includes a first red component value, a first green component value, and a first blue component value. The magnitudes of the first red component value, the first green component value, and the first blue component value are compared, and the maximum value of the three is determined as the first maximum component value and recorded as the first color value. The second solution color information includes light intensity, a second red component value, a second green component value, and a second blue component value. The magnitudes of the second red component value, the second green component value, and the second blue component value are compared, and the maximum value of the three is determined as the second maximum component value.

[0008] Optionally, the operation of acquiring the second solution color information and the first solution color information is repeated at least twice, and the second solution color information and the first solution color information are recorded each time, so as to obtain the maximum and minimum values ​​of the light intensity, the average value of the second maximum component value, the range of the first maximum component value, and the range of the first color value.

[0009] Optionally, the test using the color titration device includes: before the start of the test reaction, the color titration device adds the reagent to the titration cup and obtains a third red component value, a third green component value, and a third blue component value; comparing the magnitudes of the third red component value, the third green component value, and the third blue component value; determining the maximum value of the three as the third maximum component value; and the difference between the third maximum component value and the average value of the second maximum component value as a compensation value.

[0010] Optionally, the experiment conducted using the color titration device further includes: after the reagent is added to the titration cup, the color titration device continuously titrates the standard titrant into the reagent, and displays the experimental data in real time on the color titration device; acquiring the fourth red component value, the fourth green component value, and the fourth blue component value monitored in real time during the experiment, and recording the second color value; comparing the magnitudes of the fourth red component value, the fourth green component value, and the fourth blue component value, determining the maximum value of the three as the fourth maximum component value; determining whether the value resulting from the superposition of the fourth maximum component value and the compensation value is within the range of the first maximum component value; if it is less than the range, continuing the titration; determining whether the second color value is within the range of the first color value; if it is less than the range, continuing the titration; after a specified time, sequentially returning to determine whether the value resulting from the superposition of the fourth maximum component value and the compensation value and the second color value are within the specified range; if they are not within the specified range, continuing the titration; stopping the titration, recording the consumption value of the standard titrant, and displaying it on the color titration device.

[0011] This disclosure also provides a color titration apparatus for performing the above-described method for determining titration color. The color titration apparatus includes: a housing; a titration cup placed inside the housing; a titration device for titrating a standard titrant into the titration cup; a light source disposed inside the housing and illuminating the titration cup; a color sensor disposed opposite to the light source to receive light passing through the titration cup for detecting the color of the solution in the titration cup; and a controller for controlling whether the titration apparatus operates and recording the workload of the titration apparatus based on the color signal received from the color sensor.

[0012] Optionally, the titration cup is cylindrical, with planar and parallel detection windows on opposite sides of the bottom. The light source is located at one of the detection windows and is perpendicular to it, while the color sensor is located at the other detection window and faces the light source.

[0013] Optionally, the color titration device further includes a magnetic stirring device disposed inside the housing. The bottom of the titration cup is flat for placement on the magnetic stirring device. The magnetic stirring device is electrically connected to the controller to control the switching and rotation speed of the magnetic stirring device.

[0014] Optionally, the color titration device further includes a display screen disposed on the outer surface of the housing. The display screen is electrically connected to the controller and is used to receive signals from the controller and display test data on the display screen.

[0015] Through the above technical solution, the titration color determination method provided in this disclosure involves manually titrating the standard titrant into the reagent required for the experiment and manually determining whether the reaction has reached the endpoint. The color titration device is used to obtain the first solution color information when the reaction endpoint is manually confirmed. When the color titration device detects that the solution color information has reached the first solution color information, the titration is stopped and the consumption value of the standard titrant is recorded. A standard value is first established manually, and then the detection value of the color titration device during the experiment is compared with the manually established standard value. The titration is stopped when the standard value is reached. On the one hand, this method replaces manual determination of the endpoint of color titration, is quick and labor-saving, and has high repeatability. On the other hand, it avoids errors between instrument and manual determination results.

[0016] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:

[0018] Figure 1 This is a flowchart illustrating the process of manually determining the endpoint of an experimental reaction in this disclosure;

[0019] Figure 2 This is a schematic diagram of the process of conducting experiments using a color titration device in this disclosure;

[0020] Figure 3 This is a schematic diagram of the color titration apparatus disclosed herein;

[0021] Figure 4 This is an internal structural diagram of the color titration apparatus disclosed herein;

[0022] Figure 5 This is a front view of the titration cup in this disclosure;

[0023] Figure 6 This is a side view of the titration cup in this disclosure;

[0024] Figure 7 This is a system connection diagram of the control system in this disclosure.

[0025] Explanation of reference numerals in the attached figures

[0026] 1. Housing; 2. Liquid dispensing device; 3. Titration device; 4. Display screen; 5. Support rod; 6. Cup holder; 7. Base; 8. Titration cup; 9. Color sensor; 10. Light source; 101. Bulb; 102. Focusing housing; 11. Controller; 12. Magnetic stirring device; 13. Fixing plate; 14. Damping plate; 15. Detection window. Detailed Implementation

[0027] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0028] In this disclosure, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" generally refer to the upper, lower, top, and bottom of the corresponding component in the direction of gravity during its use. Furthermore, it should be noted that terms such as "first," "second," "third," and "fourth" are used to distinguish one element from another and do not indicate sequence or importance. Additionally, in the description with reference to the accompanying drawings, the same reference numerals in different drawings denote the same element.

[0029] In conventional implementations, titrators typically measure changes in ion concentration by measuring changes in electrode potential, thereby controlling the reaction endpoint. The instrument typically identifies the endpoint as pH=7. However, due to the different indicators used, the indicator color changes over a pH range. For example, in acid titration of alkali using phenolphthalein as an indicator, the endpoint is manually determined by the color change. The solution only changes color when the pH reaches 8 (phenolphthalein's color change range is pH=8-10). In this case, the manual judgment that the titration has reached the endpoint will be higher than the instrument's measurement of pH=7, resulting in an error between the instrument and the manual judgment. If a colorimetric titrator is used, the endpoint is determined directly by color. The endpoint value in a colorimetric titrator is a fixed value and is not calibrated against the manual judgment, which also leads to errors between the instrument and the manual judgment.

[0030] like Figure 1-2 As shown, this disclosure provides a method for determining the color of a titration, comprising the following steps: manually titrating a standard titrant into the reagent required for the experiment and manually determining whether the reaction has reached the endpoint; obtaining the first solution color information at the endpoint of the experiment using a color titration device to establish a standard value; conducting the experiment using the color titration device, stopping the titration when the solution color information reaches the first solution color information and recording the consumption value of the standard titrant.

[0031] Through the above technical solution, the titration color determination method provided in this disclosure involves manually titrating the standard titrant to the reagent required for the experiment and manually determining whether the reaction has reached the endpoint. The color titration device is used to obtain the first solution color information when the reaction endpoint is manually confirmed. When the color titration device detects that the solution color information has reached the first solution color information, the titration is stopped and the consumption value of the standard titrant is recorded. A standard value is first established manually, and then the detection value of the color titration device during the experiment is compared with the manually established standard value. The titration is stopped when the standard value is reached. On the one hand, this method replaces manual determination of the endpoint of color titration, is quick and labor-saving, and has high repeatability. On the other hand, it avoids errors between instrument and manual determination results.

[0032] As an optional implementation method, such as Figure 1-2 As shown, before the test reaction begins, the reagent must be added to the titration cup 8 and the stirring should be turned on. The stirring speed should be such that the mixture is homogeneous but no bubbles are generated, and no vortex is generated at the detection window 15. This is because the generated vortex will cause the liquid to contain air, resulting in uneven thickness and affecting color recognition. The color information of the second solution before the test reaction begins is obtained through the color titration device. Before the test reaction begins, the reagent has been added but the titration operation has not yet started.

[0033] The standard values ​​include color information for the first solution and color information for the second solution. The first solution color information includes a first red component value, a first green component value, and a first blue component value. The values ​​of the first red component value, the first green component value, and the first blue component value are compared, and the maximum value among them is determined as the first maximum component value and recorded as the first color value. The second solution color information includes light intensity, a second red component value, a second green component value, and a second blue component value. The values ​​of the second red component value, the second green component value, and the second blue component value are compared, and the maximum value among them is determined as the second maximum component value. The color titration device only needs to acquire the component values ​​of red, green, and blue. Red, green, and blue are the three primary colors, and using these three primary colors, any color perceptible to human vision can be mixed. The color value refers to the color value corresponding to that color in different color modes. In the RGB color mode, a color is formed by mixing red, green, and blue, and the color is defined by a hexadecimal symbol composed of the values ​​of red, green, and blue (RGB). The minimum value for each color is 0 (hexadecimal: #00), and the maximum value is 255 (hexadecimal: #FF).

[0034] Optionally, the operation of acquiring the color information of the second solution and the color information of the first solution is repeated at least twice, and the color information of the second solution and the color information of the first solution are recorded each time to obtain the maximum and minimum values ​​of light intensity, the average value of the second maximum component value, the range of the first maximum component value, and the range of the first color value. The maximum and minimum values ​​of light intensity before the reaction begins are calculated to determine whether to place the titration cup 8 and whether to add liquid, so as to determine whether the experimental operation can begin. The principle of performing this step is that after placing the titration cup 8 or adding liquid, the light intensity will decrease due to the refraction and scattering of light. That is, when the light intensity is greater than the maximum value, the titration operation cannot be started. The range of the first maximum component value and the range of the first color value are recorded as the judgment range for the reaction endpoint. The manual experiment is repeated multiple times to obtain the range and average value of the standard values, reduce the error of manual judgment, and make the data more accurate when comparing the detection values ​​obtained by the color titration device with the manually established standard values.

[0035] Optionally, the experiment is conducted using a color titration device, including: before the start of the experimental reaction, the color titration device adds reagent to the titration cup 8 and obtains the third red component value, the third green component value, and the third blue component value. The magnitudes of the third red component value, the third green component value, and the third blue component value are compared, and the maximum value of the three is determined as the third maximum component value. The difference between the average of the third maximum component value and the second maximum component value is the compensation value. The compensation value is the difference between the average of the third maximum component value obtained by the color titration device before the start of the experimental reaction and the average of the second maximum component value obtained by the manual experiment before the start of the reaction. In other words, it is the error between the color titration device experiment and the manual experiment before the start of the reaction. Because the reagents for each reaction will be slightly different, such as concentration and color, it is difficult to make them exactly the same each time. These differences will cause the final reaction result to be inaccurate. Therefore, the compensation value before the reaction is determined first, and then the compensation value is added at the end of the reaction to obtain the end value of the reaction, which is used to eliminate the error. The compensation value can be a positive number, a negative number, or zero.

[0036] In addition, the experiment using a color titration device also includes: after adding the reagent to the titration cup 8, the standard titrant is continuously titrated into the reagent. The titration speed should be fast at first and then slow down. During the experiment, the speed should be fast when the difference between the fourth maximum component value and the first maximum component value is large, and slow down when the difference is small. The experimental data is displayed in real time on the color titration device, and the experimental data may include the curve of the fourth maximum component value changing over time and the consumption of the standard titrant, etc.; the fourth red component value, fourth green component value, and fourth blue component value are acquired and recorded as second color values ​​during the experiment; the magnitudes of the fourth red component value, fourth green component value, and fourth blue component value are compared, and the maximum value among the three is determined as the fourth maximum component value. If the sum of the fourth maximum component value and the compensation value is within the range of the first maximum component value, and is less than that range, continue titration; otherwise, proceed to the next step. If the second color value is within the range of the first color value, and is less than that range, continue titration; otherwise, proceed to the next step. After a specified time, return sequentially to determine if the sum of the fourth maximum component value and the compensation value, as well as the second color value, are within the specified range. If they are not within the specified range, continue titration; otherwise, proceed to the next step. This step allows the two solutions sufficient reaction time to ensure accurate final experimental results; the specified time is generally 30 seconds. Stop titration, record the consumption value of the standard titrant, and calculate the content of solute reacting with the standard titrant in the reagent, which is then displayed by the color titration device.

[0037] like Figure 3-7As shown, this disclosure also provides a color titration apparatus for performing the above-described method for determining titration color. The color titration apparatus includes: a housing 1; a titration cup 8 placed inside the housing 1, for example, the housing 1 has a placement groove for accommodating the titration cup 8; a titration device 3, which is a micro-titering device 3, used to titrate a standard titrant into the titration cup 8; a light source 10, disposed inside the housing 1 and illuminating the titration cup 8, for example, the light source 10 includes a bulb 101 and a focusing housing 102, the bulb 101 being an LED bulb 101 that generates a white light source 10; the focusing housing 102 being a hemispherical curved surface that converges the light generated by the LED bulb 101; and a color sensor 9, for example... If an RGB color sensor 9 is used, a device capable of detecting and analyzing the intensity of red, green, and blue primary colors should be selected. It should be positioned opposite the light source 10 to receive the light passing through the titration cup 8, and used to detect the color of the solution in the titration cup 8. The controller 11, such as a microcontroller, has data processing and recording functions. It is used to control whether the titration device 3 works and to record the workload of the titration device 3 based on the color signal received from the color sensor 9. The titration device 3 is electrically connected to the controller 11. The workload of the titration device 3 is the consumption value of the standard titrant. The controller 11 can also control the titration speed of the titration device 3 and record the detection value of the color sensor 9.

[0038] As an optional implementation method, such as Figure 4-6As shown, the titration cup 8 is cylindrical in shape. At the bottom of this cylinder, on opposite sides, are planar and parallel detection windows 15. A light source 10 is positioned at one of the detection windows 15 and perpendicular to it. A color sensor 9 is positioned at the other detection window 15 and faces the light source 10. Detection windows 15 are provided because the wall of the titration cup 8 is arc-shaped; after light is irradiated, refraction and scattering reduce the light intensity, affecting the detection data. For example, a fixing plate 13 is circumferentially located at the mouth of the titration cup 8 for fixing it to the cup holder 6. The cup holder 6 has a through hole at its center, corresponding to the titration cup 8 and with a diameter smaller than the outer diameter of the fixing plate 13. The titration cup 8 is placed in the through hole from top to bottom. The cup holder 6 is mounted on the outside of the housing 1 via a support rod 5. The cup holder 6 can move and be fixed on the support rod 5. When the cup holder 6 rotates to the top of the housing 1, its central through hole aligns with the placement groove. The bottom of the support rod 5 is connected to the housing 1 via a base 7. A damping plate 14 is fitted onto the outside of the titration cup 8. The plate 14 is made of latex and is height-adjustable. It is used to fix the titration cup 8 on the placement slot of the color titration device to fix the position of the titration cup 8. When in use, first place the titration cup 8 on the cup holder 6, then put on the damping plate 14, adjust the height of the cup holder 6 so that the bottom of the titration cup 8 is higher than the upper surface of the housing 1, then rotate the cup holder 6 so that the titration cup 8 is above the placement slot, and slide the cup holder 6 down to place the titration cup 8 in the placement slot to fix the titration cup 8. At the same time, after use, the cup holder 6 can also be used to place the titration cup 8.

[0039] As an optional implementation method, such as Figure 4 As shown, the color titration apparatus also includes a magnetic stirring device 12, which is disposed inside the housing 1, for example, at the bottom of the placement tank. The bottom of the titration cup 8 is flat and is used to place it on the magnetic stirring device 12. The magnetic stirring device 12 is electrically connected to the controller 11 to control the switching and rotation speed of the magnetic stirring device 12. The magnetic stirring device 12 is used to stir the liquid in the titration cup 8.

[0040] As an optional implementation method, such as Figure 3-4 As shown, the color titration apparatus also includes a display screen 4, which is disposed on the outer surface of the housing 1. The display screen 4 is electrically connected to the controller 11 and is used to receive signals from the controller 11 and display test data on the display screen 4. For example, the test data includes the color information of the first solution, the color information of the second solution, the real-time detected color component value, the color value, and the consumption value of the standard titrant. For example, buttons can also be provided on the housing 1, which are electrically connected to the controller 11 and can be used to control the opening, closing, and specific operation of the color titration apparatus.

[0041] For example, a color titration apparatus may also include a liquid supply and drainage device 2, which may be a water pump used to inject and drain liquid from the titration cup 8.

[0042] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0043] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0044] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A method for determining color through titration, characterized in that, Includes the following steps: The standard titrant is manually titrated into the reagent required for the experiment to carry out the reaction, and the reaction endpoint is manually determined. The color information of the first solution at the endpoint of the experiment is obtained by a color titration device to establish a standard value. The experiment was conducted using the color titration device. When the solution color information was detected to reach the first solution color information, the titration was stopped and the consumption value of the standard titrant was recorded. Before the start of the test reaction, the reagent needs to be added to the titration cup, and the color titration device is used to obtain the second solution color information before the start of the test reaction. The first solution color information includes the first red component value, the first green component value and the first blue component value. The values ​​of the first red component value, the first green component value and the first blue component value are compared, and the maximum value of the three is determined as the first maximum component value and the first color value is recorded. The second solution color information includes light intensity, a second red component value, a second green component value, and a second blue component value. The magnitudes of the second red component value, the second green component value, and the second blue component value are compared, and the maximum value among them is determined as the second maximum component value. The operation of acquiring the second solution color information and the first solution color information is repeated at least twice, and the second solution color information and the first solution color information are recorded each time to obtain the maximum and minimum values ​​of the light intensity, the average value of the second maximum component value, the range of the first maximum component value, and the range of the first color value. The experiment performed using the color titration device includes: Before the start of the experimental reaction, the color titration device adds the reagent to the titration cup and obtains the third red component value, the third green component value, and the third blue component value. The values ​​of the third red component value, the third green component value, and the third blue component value are compared, and the maximum value among them is determined as the third maximum component value. The difference between the third maximum component value and the average of the second maximum component values ​​is used as a compensation value. The experiment conducted using the color titration device also includes: After the reagent is added to the titration cup, the color titration device begins to continuously titrate the standard titrant into the reagent, and displays the test data in real time on the color titration device. The fourth red component value, the fourth green component value, and the fourth blue component value are obtained and recorded in real time during the experiment, and the second color value is recorded. The magnitudes of the fourth red component value, the fourth green component value, and the fourth blue component value are compared, and the maximum value of the three is determined as the fourth maximum component value. It is then determined whether the value of the fourth maximum component value and the compensation value is within the range of the first maximum component value. If it is less than the range, titration continues. Determine whether the second color value is within the range of the first color value; if it is less than the range, continue titration. After a specified time, the system sequentially returns to determine whether the value of the fourth maximum component value and the compensation value, as well as the second color value, are within the specified range. If they are not within the specified range, the titration continues. Stop the titration, record the consumption value of the standard titrant, and display it using the color titration apparatus.

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