A method for quantitatively detecting the content of a central control raw material in zinc acetylacetonate produced by a water process

Abstract

The application discloses a method for quantitatively detecting content of a control raw material in water-process production of acetylacetone zinc, adopts ethyl acetate as an extractant to extract acetylacetone in a reaction mixed solution from product acetylacetone zinc monohydrate and water; the ethyl acetate extract is detected by a gas chromatograph to obtain content of acetylacetone therein, a non-polar or weakly polar chromatographic column is adopted, and GBL (gamma-butyrolactone) is used as an internal standard solution. The application solves the blank of the prior art, effectively controls a water-process production acetylacetone zinc control process, and further effectively controls COD content in waste liquid, and is beneficial to environmental governance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of chemical analysis, and particularly relates to a method for quantitatively detecting content of a control raw material in water-method production of zinc acetylacetonate. BACKGROUND

[0002] Zinc acetylacetonate monohydrate is a white crystalline powder, and its physical and chemical properties are as follows: molecular formula: C 10 H 14 O4Zn·H2O; molecular weight: 281.6; English name: Zinc acetylacetonate hydrate; CAS number: 14363-15-6.

[0003] Structural formula:

[0004]

[0005] The product is used as a thermal stabilizer for halogenated polymers such as hard PVC, and has a significant synergistic effect with stearoylbenzoylmethane and dibenzoylmethane (beta-diketone). It is also used as a catalyst, a resin crosslinking agent, a resin hardening promoter, a resin and rubber additive, a forming agent for superconducting films, heat ray reflecting glass films and transparent conductive films, etc. Currently, there are German OMNICA GMBH, French RHODIA company, Turkish AKDENIZ company and Tianjin Mosun in China that produce the product. Our company produces the raw material acetylacetone itself, so it has an advantage in producing the product, and the company researches and develops water to replace organic solvents to produce zinc acetylacetonate monohydrate.

[0006] Reaction principle:

[0007]

[0008] The product manufacturers have established internal control standards and detection methods, which are suitable for detection of finished products. However, in the production process, the process control needs to detect the content of unreacted raw materials and the amount of residual raw materials at the end of the reaction as the control index of the product. Since water is used as the solvent in the reaction, the reaction mixture contains the product zinc acetylacetonate monohydrate that has been reacted, the unreacted raw material acetylacetone and water. At present, there is no relevant literature report on the quantitative detection of the acetylacetone content in the mixture, and further the control process cannot be effectively controlled, the COD amount in the waste liquid cannot be effectively controlled, and it is not conducive to environmental governance. SUMMARY

[0009] The purpose of the present application is to provide a method for quantitatively detecting the content of a control raw material in water-method production of zinc acetylacetonate, which solves the blank of the prior art, effectively controls the control process of water-method production of zinc acetylacetonate, further effectively controls the COD amount in the waste liquid, and is conducive to environmental governance.

[0010] The technical scheme of the present application is as follows:

[0011] A method for quantitatively detecting the content of a control raw material in water-based production of acetylacetone zinc, characterized in that acetylacetone in a reaction mixture is extracted from product acetylacetone zinc monohydrate and water by using ethyl acetate as an extractant; the ethyl acetate extract is detected by a gas chromatograph to obtain the content of acetylacetone therein, a non-polar or weakly polar chromatographic column is used, and GBL (gamma-butyrolactone) is used as an internal standard solution.

[0012] The method uses a gas chromatograph, a hydrogen flame detector, and nitrogen as a carrier gas.

[0013] The method is suitable for quantitatively detecting the content of a control raw material in water-based production of acetylacetone calcium, acetylacetone aluminum and the like.

[0014] The working conditions of the gas chromatograph are as follows: SP-6801A, detector: FID, vaporization chamber temperature: 200 DEG C, detector temperature: 250 DEG C, pre-column pressure 0.05 MP, split ratio: 80:1, sample size: 0.4 ul, and column temperature is programmed to increase.

[0015] The peak time of the gas chromatograph detection spectrum is as follows: 3.3 minutes for the raw material peak, 8.7 minutes for the internal standard peak, and 2.1 minutes for the solvent ethyl acetate peak.

[0016] 1. The present application performs sample pretreatment on a reaction mixture, separates product acetylacetone zinc monohydrate, water and raw material acetylacetone therein by using an extraction method, and facilitates subsequent gas chromatograph detection.

[0017] 2. The gas chromatograph method uses a hydrogen flame detector, nitrogen as a carrier gas, and a non-polar (weakly polar) chromatographic column, thereby reducing the influence of water on the instrument and the result.

[0018] 3. The internal standard method is used to quantitatively detect the content of the raw material in the production process, the present method uses GBL (gamma-butyrolactone) as an internal standard solution, and the solvent peak, target peak and internal standard peak are well separated, and the result shows that the coefficient of the standard curve of the method reaches R 2 0.9994, and the blank standard recovery rate is 99.6%. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a peak spectrum of a raw material peak, an internal standard peak and a solvent ethyl acetate peak.

[0020] Figure 2 is a spectrum of a raw material concentration of 0.0505%.

[0021] Figure 3 is a spectrum of a raw material concentration of 0.100%.

[0022] Figure 4 Standard working curve for raw material. DETAILED DESCRIPTION

[0023] The method is used for quantitatively detecting the content of acetylacetone in the raw material for the water method production of zinc acetylacetonate.

[0024] 1. Selection of chromatographic column: Through the injection analysis of different chromatographic columns such as HP-INNOWAX and HP-5, it is found that the non-polar (weakly polar) Agilent HP-5 ((5%-phenyl)-methyl polysiloxane) is selected as the chromatographic column for the control analysis, which can well separate ethyl acetate, acetylacetone and γ-butyrolactone.

[0025] 2. Selection of extractant and internal standard: Through the determination of the peak time of ethyl acetate, γ-butyrolactone and acetylacetone, ethyl acetate is selected as the extractant of the method, which can extract acetylacetone from the product zinc acetylacetonate monohydrate and water in the reaction mixture; γ-butyrolactone is used as the internal standard of the method, which can be well separated from each substance and does not react with each substance.

[0026] 3. Determination of detection parameters and peak time of each substance: (1) Inject ethyl acetate, acetylacetone and γ-butyrolactone into the gas chromatograph respectively to determine the peak time of each substance. (2) Mix the above substances and inject them into the gas chromatograph, and adjust the analysis parameters so that each substance can be well separated:

[0027] 4. Experimental conditions: gas chromatograph: SP-6801A, detector: FID, vaporization chamber temperature: 200℃, detector temperature: 250℃, pre-column pressure 0.05MP, split ratio: 80:1, injection volume: 0.4ul, column temperature: programmed temperature rise:

[0028] Rate (°C / min) Temperature (°C) Retention time (min) 90 5 35 200 2

[0029] The characteristic spectrum of each substance is shown in Figure 1 :

[0030] As Figure 1 , 3.3 minutes is the raw material peak, 8.7 minutes is the internal standard peak, and 2.1 minutes is the solvent ethyl acetate peak.

[0031] 5. Determination of detection limit and quantitative limit: according to the quality control requirements, the raw material acetylacetone is diluted to 0.1% and 0.05% respectively, injected into the chromatograph, and the detection limit of the substance is calculated based on three times the signal-to-noise ratio; ten times the signal-to-noise ratio determines the quantitative limit.

[0032] As Figure 2 ,Figure 3 The concentration of the sample is 0.0505% and 0.100% respectively. The calculation results according to the formula are as follows:

[0033] Concentration (%) Raw material peak area Internal standard peak area Ratio Calculated content (%) 0.0505 4662 929550 0.0050155 -0.038 0.100 18547 939470 0.01974 0.101

[0034] From the actual sample results, it can be seen that at a concentration of 0.05%, the raw material has a peak, but the formula calculation content is negative; at a concentration of 0.1%, the formula calculation content is 0.101%, which is consistent with the actual value, so the final determination is 0.1% as the quantitative limit of the method.

[0035] 6. According to the quantitative limit of each substance, five-point calibration curve is made: first, accurately configure 5g / L γ-butyrolactone-ethyl acetate internal standard solution. Then accurately configure different concentrations of acetylacetone raw material mixed solution, dilute the acetylacetone raw material with water to about 0%, 1%, 2.5%, 5%, 7.5%, 10%, mix thoroughly. Take 5ml of each of the above solutions and add the same volume of ethyl acetate solution, extract thoroughly for 1 minute, centrifuge at 12800 rpm for 2 minutes, take 500ul of the upper solution after centrifugation, add 500ul of γ-butyrolactone-ethyl acetate internal standard solution, mix well, and gas chromatography sampling. Calculate the ratio of sample peak area to γ-butyrolactone area, and draw the linear relationship between raw material concentration and the ratio to make a standard curve.

[0036] Table 1: Concentration of raw material reference substance and area ratio of internal standard substance

[0037] Reference substance concentration Ratio 0 0 1.001 0.1100 2.517 0.2857 5.052 0.5501 7.489 0.8098 10.007 1.0536

[0038] From the above data, the standard working curve of the raw material is obtained Figure 4

[0039] Table 2: Standard curve and related system of raw material

[0040]

[0041] Table 3: Spiked recovery test

[0042]

[0043] The samples are treated in the same way: take 500ul of the upper extraction solution after centrifugation, add 500ul of γ-butyrolactone ethyl acetate internal standard solution, mix well, and gas chromatography sampling analysis. The data is substituted into the internal standard curve to obtain the content of the raw material.

[0044] This method uses γ-butyrolactone as an internal standard solution for gas phase quantitative detection and analysis of the product control. The results show that the coefficient of the standard curve in the range of 0.1-10% reaches R 2 0.9994, the recovery rate of standard addition is 99.6%, which can meet the needs of production control.​

[0045] The method is also applicable to the quantitative detection of acetylacetone calcium, acetylacetone aluminum and other intermediates produced by water method

[0046] Quantitative detection of the process.

Claims

1. A method for quantitative detection of the content of raw materials in the aqueous process for producing zinc acetylacetonate, characterized in that: Ethyl acetate was used as the extractant to extract acetylacetone from the product zinc acetylacetone monohydrate and water in the reaction mixture; the ethyl acetate extract was detected by gas chromatography to obtain the content of acetylacetone, using a non-polar or weakly polar chromatographic column and GBL (γ-butyrolactone) as the internal standard solution. The raw materials for the aqueous process of producing zinc acetylacetonate include acetylacetonate, zinc acetylacetonate monohydrate, and water. Detector: FID, vaporization chamber temperature: 200℃, detector temperature: 250℃, column inlet pressure: 0.05MP, split ratio: 80:1, injection volume: 0.4ul, column temperature is programmed. 。 2. The method for quantitative detection of the content of raw materials in the aqueous production of zinc acetylacetonate according to claim 1, characterized in that: Nitrogen is used as the carrier gas.

3. The method for quantitative detection of the content of raw materials in the aqueous production of zinc acetylacetonate according to claim 1, characterized in that: It is suitable for quantitative detection of the content of raw materials in the water-based production of calcium acetylacetonate and aluminum acetylacetonate.

4. The method for quantitative detection of the content of raw materials in the aqueous process for producing zinc acetylacetonate according to claim 1, characterized in that: Gas chromatograph: SP-6801A.

5. The method for quantitative detection of the content of raw materials in the aqueous production of zinc acetylacetonate according to claim 1, characterized in that: The elution times of the chromatogram detected by gas chromatography are: The peak at 3.3 minutes is the raw material peak, the peak at 8.7 minutes is the internal standard peak, and the peak at 2.1 minutes is the solvent ethyl acetate peak.

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