Method for detecting multiple parameters in complex water environment

Abstract

The invention belongs to the technical field of water quality detection, and particularly relates to a method for detecting multiple parameters in a complex water environment. The method for detecting the multiple parameters in the complex water environment mainly comprises the following steps: S1, collecting water quality, and treating the water quality to obtain a sample to be detected; s2, preparing phenol, pentachlorophenol and 2, 6-dinitro p-cresol standard sample solutions with different concentrations; s3, starting up the high performance liquid chromatography mass spectrometer, and setting various parameters; step S4, drawing a standard curve of phenol, pentachlorophenol and 2, 6-dinitro p-cresol; step S5, feeding a sample to be detected, and calculating the concentration of phenol, pentachlorophenol and 2, 6-dinitro-p-cresol in the sample to be detected by combining the peak area. According to the method for detecting the multiple parameters in the complex water environment, the content of phenol, pentachlorophenol and 2, 6-dinitro-p-cresol in industrial wastewater can be detected at the same time, the detection result is accurate, and operation is easy.

Description

Technical Field

[0001] The present invention belongs to the technical field of water quality detection, and in particular relates to a method for detecting multiple parameters in a complex water environment. Background Art

[0002] Industrial wastewater refers to wastewater and waste liquids generated during industrial production. These wastewaters contain lost industrial materials, intermediates, by-products, and pollutants generated during the production process. Industrial wastewater is diverse and complex in composition, often containing a variety of toxic substances, polluting the environment and posing a significant threat to human health. Phenolic wastewater is generated by industrial sectors such as coking plants, gas plants, petrochemical plants, and insulation materials factories, as well as by petroleum cracking to produce ethylene, synthetic phenol, polyamide fibers, synthetic dyes, organic pesticides, and phenolic resins. Phenolic wastewater primarily contains phenolic compounds, such as phenol, cresol, xylenol, and 2,6-dinitro-4-cresol. These phenolic compounds are highly toxic organic pollutants with a foul odor. They can enter the human body through the digestive tract, respiratory tract, and skin, where they bind to proteins in cell protoplasm, inactivating them. In severe cases, they can cause spinal cord irritation and lead to systemic poisoning. Irrigating farmland with high concentrations of phenolic wastewater can cause crop withering and reduced yields. Fish can also be poisoned and die if the phenol concentration in water exceeds 5 mg / L. Therefore, it is necessary to measure the content of phenolic compounds in industrial wastewater to avoid the harm caused by excessive content.

[0003] Phenol is a colorless needle-shaped crystal with a distinctive odor. It is toxic, slightly soluble in water at room temperature, and easily soluble in organic solvents. Pentachlorophenol is highly toxic and is mainly used as a herbicide in rice fields, and as a preservative and mildew preventer for textiles, leather, paper, and wood. It is a white crystalline powder that is almost insoluble in water but easily soluble in organic solvents. 2,6-Dinitro-p-cresol is a white crystalline solid with a bitter taste. It is insoluble in water but easily soluble in most organic solvents. It can decompose at high temperatures and release toxic gases.

[0004] Existing technologies lack the ability to simultaneously detect the contents of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol in industrial wastewater, resulting in low detection efficiency and a certain amount of time cost. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides a method for detecting multiple parameters in a complex water environment, the purpose of which is to simultaneously detect the contents of phenol, pentachlorophenol and 2,6-dinitro-p-cresol in industrial wastewater. The test results are accurate, the operation is simple, and the detection is efficient.

[0006] In order to achieve the above object, the present invention provides a method for detecting multiple parameters in a complex water environment, comprising the following steps:

[0007] Step S1, collecting water, treating the collected water with an organic solvent and a saturated sodium chloride solution, dehydrating and concentrating the organic layer obtained by the treatment, adding a good solvent to the fixed volume, and filtering with a filter membrane to obtain a sample to be tested;

[0008] Step S2, weighing phenol, pentachlorophenol and 2,6-dinitro-p-cresol respectively, and preparing phenol, pentachlorophenol and 2,6-dinitro-p-cresol standard sample solutions of different concentrations;

[0009] Step S3, turning on the high performance liquid chromatography mass spectrometer and setting various parameters;

[0010] Step S4, drawing a standard curve for phenol, pentachlorophenol, and 2,6-dinitro-p-cresol, injecting different concentrations of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol standard sample solutions into a high performance liquid chromatography-mass spectrometer through a 50 μL microinjector, measuring the peak areas of the different concentrations of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol standard sample solutions, and drawing a standard curve for phenol, pentachlorophenol, and 2,6-dinitro-p-cresol with the concentration of the standard sample solution as the abscissa and the peak area as the ordinate;

[0011] Step S5: aspirate the sample to be tested using a 50 μL microinjector and inject it into a high performance liquid chromatography mass spectrometer. The peak areas of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol in the sample to be tested are determined by combining the mass spectrometer. The concentrations of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol in the sample to be tested are calculated based on the standard curves of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol.

[0012] Furthermore, in step S1, the organic solvent is one of ethyl acetate and dichloromethane.

[0013] Furthermore, in step S1, the dehydration method is to use anhydrous Na2SO4 for dehydration; and the concentration method is to use a rotary evaporator for concentration.

[0014] Furthermore, in step S1, the good solvent is methanol; the dosage of methanol is 1 to 3 mL.

[0015] Furthermore, in step S1, the filter membrane is a 0.22 μm filter membrane.

[0016] Furthermore, in step S2, the weighing is performed using a precision balance.

[0017] Furthermore, in step S3, the parameters include chromatographic column, ultraviolet detection wavelength, column temperature, mobile phase and flow rate.

[0018] Furthermore, the chromatographic column is a ZORBAX Eclipse XDB C18 chromatographic column (5 μm, 4.6 mm x 150 mm); the ultraviolet detection wavelength is 254 nm; the column temperature is 40° C.; the mobile phase is methanol / water; and the flow rate is 1.0 to 5.0 mL / min.

[0019] Furthermore, in step S4, the 50 μL micro-injector needs to be de-bubbled before injection; the injection dose into the high performance liquid chromatography mass spectrometer is 15 to 25 μL.

[0020] Furthermore, in step S5, the 50 μL micro-injector needs to be de-bubbled before injection; the injection dose into the high performance liquid chromatography mass spectrometer is 15 to 25 μL; and the sample to be tested needs to be injected three times.

[0021] Beneficial effects

[0022] The invention discloses a method for detecting multiple parameters in a complex water environment, which can realize the simultaneous detection of the contents of phenol, pentachlorophenol and 2,6-dinitro-p-cresol in industrial wastewater. The detection results are accurate and the operation is simple, thereby realizing efficient detection. The sample to be tested is injected three times, i.e., three measurements are performed. Taking the average value of the three measurements can reduce errors, ensure the accuracy of the measurement results, and make the detection results reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A flow chart of a method for detecting multiple parameters in a complex water environment;

[0024] Figure 2 is the standard curve of phenol;

[0025] Figure 3 This is the standard curve of pentachlorophenol;

[0026] Figure 4 This is the standard curve of 2,6-dinitro-p-cresol. DETAILED DESCRIPTION

[0027] The present invention is further illustrated below by means of specific examples. These examples are exemplary and are intended to illustrate the problem and explain the present invention, but are not intended to be limiting.

[0028] Example 1

[0029] A method for detecting phenolic compounds in industrial wastewater comprises the following steps:

[0030] Step S1, collecting industrial wastewater, drawing 30 mL of industrial wastewater into a 250 mL separatory funnel, adding 50 mL of ethyl acetate to extract twice, collecting the upper ethyl acetate layer, then adding 30 mL of saturated sodium chloride solution to the ethyl acetate layer for back extraction twice, dehydrating the ethyl acetate layer with anhydrous Na2SO4, concentrating it on a rotary evaporator at 40°C, adding 2 mL of methanol solution to the volume, and filtering it through a 0.22 μm filter membrane to obtain a sample to be tested;

[0031] Step S2: using a precision balance, 10 mg of each of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol were weighed, 100 mL of methanol solution was added, and a preliminary sample solution of 100 mg / L was prepared. The solution was then gradiently diluted to obtain an intermediate sample solution with a concentration of 1000 μg / L, which was further diluted to obtain standard sample solutions with concentrations of 1, 5, 10, 20, and 50 μg / L.

[0032] Step S3, the high performance liquid chromatography mass spectrometer is turned on and various parameters are set. The high performance liquid chromatography mass spectrometer uses a ZORBAX Eclipse XDB C18 chromatographic column (5 μm, 4.6 mm x 150 mm), an ultraviolet detection wavelength of 254 nm, a column temperature of 40° C., methanol / water as the mobile phase, and a flow rate of 1.5 mL / min.

[0033] Step S4, plotting standard curves for phenol, pentachlorophenol, and 2,6-dinitro-p-cresol. Pipette 1 mL of a 1 μg / L phenol standard sample solution into a sample tube, use a 50 μL microinjector to draw the phenol standard sample solution, expel any bubbles in the microinjector, inject 20 μL of the phenol standard sample solution into a high-performance liquid chromatography-mass spectrometer, and measure the peak area. Repeat the above steps to measure the peak areas of 5, 10, 20, and 50 μg / L phenol standard sample solutions, plotting a standard curve for phenol using the concentration of the phenol standard sample solution as the horizontal axis and the peak area as the vertical axis. Repeat the above steps to plot standard curves for pentachlorophenol and 2,6-dinitro-p-cresol.

[0034] Step S5, using a 50 μL microinjector to draw the sample to be tested in step S1, expelling bubbles in the microinjector, injecting 20 μL of the sample to be tested into a high performance liquid chromatography mass spectrometer, measuring the peak area, and determining the peak time and peak area of ​​phenol, pentachlorophenol, and 2,6-dinitro-p-cresol in combination with the mass spectrometer. The concentrations of phenol, pentachlorophenol, and 2,6-dinitro-p-cresol can be obtained by combining with the standard curve. The sample to be tested is measured three times to ensure the accuracy of the measurement result.

[0035] Content of phenolic compounds in industrial wastewater

[0036] The peak areas obtained by three measurements in Example 1 and the concentrations of phenol, pentachlorophenol and 2,6-dinitro-p-cresol calculated according to the standard curve are summarized in Table 1. From the data analysis in Table 1, it can be found that the content of pentachlorophenol in the test sample is the highest, followed by 2,6-dinitro-p-cresol, and phenol is the lowest.

[0037] Table 1 Concentration data of phenol, pentachlorophenol and 2,6-dinitro-p-cresol

[0038]

Claims

1. A method for detecting multiple parameters in a complex water environment, characterized in that: The steps include: Step S1, collecting water, treating the collected water with an organic solvent and a saturated sodium chloride solution, dehydrating and concentrating the organic layer obtained by the treatment, adding a good solvent to the fixed volume, filtering with a filter membrane, and obtaining a sample to be tested; Step S2, weighing phenol, pentachlorophenol and 2,6-dinitro-p-cresol respectively, and preparing phenol, pentachlorophenol and 2,6-dinitro-p-cresol standard sample solutions with different concentrations; Step S3, turning on the high performance liquid chromatography mass spectrometer and setting various parameters; Step S4, drawing a standard curve of phenol, pentachlorophenol and 2,6-dinitro-p-cresol, injecting different concentrations of phenol, pentachlorophenol and 2,6-dinitro-p-cresol standard sample solutions into a high performance liquid chromatography-mass spectrometer through a 50 μL microinjector, measuring the peak areas of different concentrations of phenol, pentachlorophenol and 2,6-dinitro-p-cresol standard sample solutions, and drawing a standard curve of phenol, pentachlorophenol and 2,6-dinitro-p-cresol with the concentration of the standard sample solution as the abscissa and the peak area as the ordinate; Step S5, using a 50 μL microinjector to draw the sample to be tested, injecting it into a high performance liquid chromatography-mass spectrometer, and determining the peak areas of phenol, pentachlorophenol and 2,6-dinitro-p-cresol in the sample to be tested by combining with the mass spectrometer, and calculating according to the standard curves of phenol, pentachlorophenol and 2,6-dinitro-p-cresol to obtain the concentrations of phenol, pentachlorophenol and 2,6-dinitro-p-cresol in the sample to be tested.

2. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S1, the organic solvent is one of ethyl acetate and dichloromethane.

3. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S1, the dehydration method is to use anhydrous Na2SO4 for dehydration; and the concentration method is to use a rotary evaporator for concentration.

4. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S1, the good solvent is methanol; the dosage of the methanol is 1-3 mL.

5. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S1, the filter membrane is a 0.22 μm filter membrane.

6. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S2, the weighing method is to use a precision balance to weigh.

7. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S3, the various parameters include chromatographic column, ultraviolet detection wavelength, column temperature, mobile phase and flow rate.

8. The method for detecting multiple parameters in a complex water environment according to claim 7, characterized in that: The chromatographic column is a ZORBAX Eclipse XDB C18 chromatographic column (5 μm, 4.6 mm x 150 mm); the ultraviolet detection wavelength is 254 nm; the column temperature is 40° C.; the mobile phase is methanol / water; and the flow rate is 1.0 to 5.0 mL / min.

9. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S4, the 50 μL micro-injector needs to be used to expel bubbles before injection; the injection dose into the high performance liquid chromatography-mass spectrometer is 15-25 μL.

10. The method for detecting multiple parameters in a complex water environment according to claim 1, characterized in that: In step S5, the 50 μL micro-injector needs to be exhausted before injection; the injection dose into the high performance liquid chromatography mass spectrometer is 15-25 μL; and the sample to be tested needs to be injected three times.

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