Preparation method and application of colorimetric detection card for volatile phenolic compounds
By using the metal-organic framework material UiO-66-NH2 to encapsulate the indicator, a colorimetric detection card was prepared, which solved the problem of the complexity of detecting volatile phenolic compounds in the prior art and achieved a simple and highly sensitive gas detection effect.
Patent Information
- Application Number
- CN202411089315.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-08
- Publication Date
- 2026-02-10
AI Technical Summary
Existing methods for detecting volatile phenolic compounds require complex instruments or cannot directly respond to gases, making it impossible to prepare portable colorimetric detection cards and achieve simple and sensitive gas detection.
A colorimetric detection card for volatile phenolic compounds was prepared by encapsulating a 2,6-dichloroquinone-4-chloroimine indicator with the metal-organic framework material UiO-66-NH2, and detection was achieved through direct contact reaction.
The prepared colorimetric detection card has high stability and high sensitivity, and can develop a color reaction within 10 minutes, making it suitable for the detection of volatile phenolic compounds in various scenarios.
Smart Images
Figure CN121499476A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a method for preparing a colorimetric detection card for volatile phenolic compounds and its application, belonging to the field of rapid detection technology for volatile gases. Background Technology
[0002] Volatile phenolic compounds generally refer to phenolic compounds with boiling points below 230°C, which can evaporate with water vapor. Volatile phenolic compounds are toxic to humans; acute poisoning symptoms include vomiting, diarrhea, and dizziness, while long-term exposure may lead to headaches, rashes, itching, anemia, and neurological symptoms. Due to their wide range of industrial applications and potential environmental risks, volatile phenolic compounds require strict management and control during production, use, and emission; therefore, monitoring of these compounds is necessary.
[0003] Existing methods for detecting volatile phenolic compounds mainly include gas chromatography and spectrophotometry. Gas chromatography offers high sensitivity and accuracy, but requires specialized instruments and is relatively cumbersome to operate. Spectrophotometry uses chemical colorimetric reagents to react with phenols under specific conditions to generate color products, primarily targeting volatile phenolic compounds in aqueous media. It cannot directly and effectively respond to volatile phenolic gaseous compounds, nor can the corresponding colorimetric reagents be prepared into portable colorimetric detection cards. Both of these methods have limitations in practical applications; therefore, there is a need to develop a simple, sensitive, and easily stored colorimetric detection card for the rapid detection of volatile phenolic gaseous compounds in the environment. Summary of the Invention
[0004] The purpose of this invention is to provide a colorimetric card for rapid detection of volatile phenolic compound gases based on the colorimetric principle. This colorimetric card has good stability, high sensitivity, and can directly react with phenolic compound gases, making it applicable to a wide range of scenarios.
[0005] According to one aspect of this application, a method for preparing a colorimetric detection card for volatile phenolic compounds is provided, the method comprising at least the following steps:
[0006] Step I: Mix ZrCl4, 2-aminoterephthalic acid, ethanol, and formic acid, and react them to obtain MOFs material UiO-66-NH2;
[0007] Step II: Mix the MOFs material UiO-66-NH2 obtained in Step I, ethanol, and 2,6-dichloroquinone-4-chloroimine, and stir to obtain the MOFs material UiO-66-NH2 encapsulating 2,6-dichloroquinone-4-chloroimine.
[0008] Step III: The MOF material UiO-66-NH2 encapsulated with 2,6-dichloroquinone-4-chloroimine obtained in Step II was mixed with ethanol and coated onto a substrate to obtain a colorimetric detection card for volatile phenolic compounds.
[0009] Optionally, in step I, the molar ratio of ZrCl4 to 2-aminoterephthalic acid is 2:1;
[0010] The molar concentration of ZrCl4 in ethanol is 0.075–0.4 mol / L;
[0011] The volume ratio of ethanol to formic acid is 0.3:1 to 1.4:1.
[0012] Optionally, in step I, the reaction conditions are as follows:
[0013] The reaction time is 12–24 hours;
[0014] The reaction temperature is 120–150°C.
[0015] Optionally, in step II, the concentration of the MOF material UiO-66-NH2 in ethanol is 50-100 mg / mL;
[0016] The concentration of the 2,6-dichloroquinone-4-chloroimine indicator is 10–20 g / L.
[0017] Optionally, the stirring speed is 300 to 400 r / min.
[0018] Optionally, in step III, the concentration of the MOF material UiO-66-NH2 encapsulating 2,6-dichloroquinone-4-chloroimine in ethanol is 10–20 g / L.
[0019] Optionally, in step III, the substrate is selected from at least one of polyvinylidene fluoride membrane and PE membrane.
[0020] According to another aspect of this application, an application of a colorimetric detection card for volatile phenolic compounds is provided, wherein the colorimetric detection card is contacted and reacted with volatile phenolic compounds;
[0021] Optionally, the volatile phenolic compound is selected from at least one of phenol, catechol, resorcinol, hydroquinone, and phloroglucinol.
[0022] Optionally, the contact reaction time is 10 to 30 minutes;
[0023] The temperature of the contact reaction is 25–35°C.
[0024] The beneficial effects that this application can produce include:
[0025] 1) The constructed colorimetric detection card for volatile phenolic compounds uses a metal-organic framework material to encapsulate the indicator, which improves the stability of the indicator. Therefore, the detection card has high stability and a long shelf life.
[0026] 2) The colorimetric detection card for volatile phenolic compounds can directly measure phenolic compound gases. It only requires 10 minutes of contact reaction to obtain obvious color change results. It has high detection sensitivity and is easy to operate. Attached Figure Description
[0027] Figure 1 This study compares the performance of a test card prepared by encapsulating 2,6-dichloroquinone-4-chloroimine with MOF material UiO-66-NH2 and a test card prepared by dissolving 2,6-dichloroquinone-4-chloroimine in ethanol in detecting catechol, as well as the effect of storage time on the performance of the two test cards.
[0028] Figure 2 The image shows the XRD pattern of the MOF material UiO-66-NH2 in Example 1 of this application before and after encapsulation of 2,6-dichloroquinone-4-chloroimine. Detailed Implementation
[0029] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0030] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels;
[0031] The preparation examples and analytical methods in this application are as follows:
[0032] The MOF materials before and after encapsulation with the indicator were tested using an X-ray diffractometer (model EmpyreamX).
[0033] Preparation Example 1.
[0034] Preparation of metal-organic framework material UiO-66-NH2: 2 mmol of ZrCl4 and 1 mmol of 2-aminoterephthalic acid were weighed into a beaker, and 15 mL of ethanol and 20 mL of 30% formic acid were added. After mixing, the mixture was sonicated for 10 min, followed by stirring for 20 min. The homogeneous mixture was transferred to a polytetrafluoroethylene reactor and placed in an oven at 120 °C for 12 hours. After cooling to room temperature, the resulting precipitate was centrifuged and washed three times repeatedly with ethanol. Finally, it was dried in a vacuum oven at 60 °C to obtain a white powdery MOF material UiO-66-NH2.
[0035] Preparation Example 2.
[0036] Preparation of metal-organic framework material UiO-66-NH2: 4 mmol of ZrCl4 and 2 mmol of 2-aminoterephthalic acid were weighed into a beaker, and 20 mL of ethanol and 30 mL of 40% formic acid were added. The mixture was sonicated for 20 min, followed by stirring for 20 min. The homogeneous mixture was transferred to a polytetrafluoroethylene reactor and placed in an oven at 120 °C for 12 hours. After cooling to room temperature, the precipitate was centrifuged and washed repeatedly with ethanol five times. Finally, it was dried in a vacuum oven at 60 °C to obtain a white powdery MOF material UiO-66-NH2.
[0037] Preparation Example 3.
[0038] Preparation of metal-organic framework material UiO-66-NH2: 1.5 mmol of ZrCl4 and 0.75 mmol of 2-aminoterephthalic acid were weighed into a beaker, and 10 mL of ethanol and 15 mL of 50% formic acid were added. After mixing, the mixture was sonicated for 15 min, followed by stirring for 10 min. The homogeneous mixture was transferred to a polytetrafluoroethylene reactor and placed in an oven at 120 °C for 12 hours. After cooling to room temperature, the resulting precipitate was centrifuged and washed repeatedly with ethanol four times. Finally, it was dried in a vacuum oven at 60 °C to obtain a white powdery MOF material UiO-66-NH2.
[0039] Example 1.
[0040] Preparation of colorimetric detection cards for volatile phenolic compounds:
[0041] The metal-organic framework material UiO-66-NH2 prepared in Preparation Example 1 was dispersed in ethanol to a concentration of 80 mg / L. A 2,6-dichloroquinone-4-chloroimine indicator was added to the ethanol to a concentration of 15 g / L. After stirring at 350 r / min at room temperature for 24 h, the product was centrifuged, filtered, and repeatedly washed to obtain the MOF material encapsulating 2,6-dichloroquinone-4-chloroimine. Figure 2 This indicates that the prepared MOFs material has good phase purity and that the MOFs material successfully encapsulates the indicator. The material was ultrasonically dispersed in ethanol at a concentration of 10 g / L and then uniformly drop-coated onto a polyvinylidene fluoride membrane to obtain a colorimetric detection card for volatile phenolic compounds.
[0042] Example 2.
[0043] Preparation of colorimetric detection cards for volatile phenolic compounds:
[0044] The metal-organic framework material UiO-66-NH2 prepared in Preparation Example 1 was dispersed in ethanol to a concentration of 100 mg / L. 2,6-dichloroquinone-4-chloroimine indicator was added to the ethanol to a concentration of 20 g / L. After stirring at room temperature at 400 r / min for 24 h, the product was centrifuged, filtered, and repeatedly washed to obtain MOFs material encapsulating 2,6-dichloroquinone-4-chloroimine. This material was ultrasonically dispersed in ethanol at a concentration of 20 g / L and then uniformly drop-coated onto a polyvinylidene fluoride membrane to obtain a colorimetric detection card for volatile phenolic compounds.
[0045] Example 3.
[0046] Preparation of colorimetric detection cards for volatile phenolic compounds:
[0047] The metal-organic framework material UiO-66-NH2 prepared in Preparation Example 1 was dispersed in ethanol to a concentration of 50 mg / L. 2,6-dichloroquinone-4-chloroimine indicator was added to the ethanol to a concentration of 10 g / L. After stirring at 300 r / min at room temperature for 24 h, the product was centrifuged, filtered, and repeatedly washed to obtain MOFs material encapsulating 2,6-dichloroquinone-4-chloroimine. This material was ultrasonically dispersed in ethanol at a concentration of 15 g / L and then uniformly drop-coated onto a polyvinylidene fluoride membrane to obtain a colorimetric detection card for volatile phenolic compounds.
[0048] Example 4.
[0049] The test card prepared in Example 1 is designated as Test Card 1; the test card prepared by directly dissolving 10 g / L of indicator 2,6-dichloroquinone-4-chloroimine in ethanol is designated as Test Card 2. Both test cards were directly reacted with volatile catechol gas for 10 min, and the detection results are as follows: Figure 1 As shown in the figure, the indicator encapsulated with MOFs exhibits more sensitive color development. The effect of storage time on the performance of the two test cards was examined. The results show that the colorimetric test card with the MOF-encapsulated indicator is more stable, maintaining its performance for one month. In contrast, the colorimetric test card using an indicator dissolved directly in ethanol failed to respond effectively to catechol volatile gases by day 7. Figure 1 ).
[0050] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A method for preparing a colorimetric detection card for volatile phenolic compounds, characterized in that, The method includes at least the following steps: Step I: Mix ZrCl4, 2-aminoterephthalic acid, ethanol, and formic acid, and react to obtain MOF material UiO-66-NH2; Step II: Mix the MOFs material UiO-66-NH2 obtained in Step I, ethanol, and 2,6-dichloroquinone-4-chloroimine, and stir to obtain the MOFs material UiO-66-NH2 encapsulating 2,6-dichloroquinone-4-chloroimine. Step III: The MOF material UiO-66-NH2 encapsulated with 2,6-dichloroquinone-4-chloroimine obtained in Step II was mixed with ethanol and coated onto a substrate to obtain a colorimetric detection card for volatile phenolic compounds.
2. The preparation method according to claim 1, characterized in that, In step I, the molar ratio of ZrCl4 to 2-aminoterephthalic acid is 2:1; The molar concentration of ZrCl4 in ethanol is 0.075–0.4 mol / L; The volume ratio of ethanol to formic acid is 0.3:1 to 1.4:
1.
3. The preparation method according to claim 1, characterized in that, In step I, the reaction conditions are as follows: The reaction time is 12–24 hours; The reaction temperature is 120–150°C.
4. The preparation method according to claim 1, characterized in that, In step II, the concentration of the MOF material UiO-66-NH2 in ethanol is 50-100 mg / mL; The concentration of the 2,6-dichloroquinone-4-chloroimine indicator is 10–20 g / L.
5. The preparation method according to claim 1, characterized in that, In step II, the stirring speed is 300 to 400 r / min.
6. The preparation method according to claim 1, characterized in that, In step III, the concentration of the MOF material UiO-66-NH2 encapsulating 2,6-dichloroquinone-4-chloroimine in ethanol is 10-20 g / L.
7. The preparation method according to claim 1, characterized in that, In step III, the substrate is selected from at least one of polyvinylidene fluoride membrane and PE membrane.
8. The application of the colorimetric detection card for volatile phenolic compounds obtained by any one of the preparation methods of claims 1 to 7 in the detection of volatile phenolic compounds.
9. The application according to claim 8, characterized in that, The volatile phenolic compound is selected from at least one of phenol, catechol, resorcinol, hydroquinone, and phloroglucinol.
10. The application according to claim 8, characterized in that, The volatile phenolic compounds react with each other upon contact. Preferably, the contact reaction time is 10–30 min; The temperature of the contact reaction is 25–35°C.