Simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2-and NO3Method of (a)
阅读说明：本技术 同时快速分析磷酸二丁酯、磷酸一丁酯、正丁酸、甲酸、no2-和no3-的方法 (Simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2-and NO3Method of (a) ) 是由 王思宇 王锦花 唐双淩 赵欣宇 陈雨 陈丹红 于 2021-08-12 设计创作，主要内容包括：本发明公开了一种同时、快速分析磷酸二丁酯、磷酸单丁酯、n-C-(3)H-(7)COO～(-)、HCOO～(-)、NO-(2)～(-)和NO-(3)～(-)的方法,将含有六种目标物质标品溶解于纯水中配制成标准储备液,再制作不同浓度样本溶液,通过离子色谱法分析,得到离子色谱标准谱图及相应组分的峰面积,绘制各目标物质标准工作曲线；取待测样品离心分离,提取上层有机相,使用定量Na-(2)CO-(3)-NaOH水溶液对分离得到的有机相进行反萃洗脱,再离心分离,提取下层水相,稀释；再进行离子色谱法分析,测得待测样品提取液离子色谱图中相应组分的峰面积,再利用标准工作曲线及待测样品稀释倍数,计算得到待测样品中各目标物质浓度。本发明用离子色谱法,能同时、快速分析有机相中六种目标物质,分析灵敏度高、检测限低、重复性好。(The invention discloses a method for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate and n-C 3 H 7 COO ‑ 、HCOO ‑ 、NO 2 ‑ And NO 3 ‑ Dissolving a standard substance containing six target substances in pure water to prepare a standard stock solution, then preparing sample solutions with different concentrations, analyzing by ion chromatography to obtain an ion chromatography standard spectrogram and peak areas of corresponding components, and drawing a standard working curve of each target substance; taking a sample to be testedCentrifuging, extracting upper organic phase, and using quantitative Na 2 CO 3 The organic phase obtained by separation is subjected to back extraction elution by NaOH aqueous solution, and then is subjected to centrifugal separation to extract a lower aqueous phase and dilute the lower aqueous phase; and then carrying out ion chromatography analysis to measure peak areas of corresponding components in the ion chromatogram of the extracting solution of the sample to be measured, and calculating to obtain the concentration of each target substance in the sample to be measured by using the standard working curve and the dilution factor of the sample to be measured. The invention uses ion chromatography, can simultaneously and rapidly analyze six target substances in the organic phase, and has high analysis sensitivity, low detection limit and good repeatability.)
1. Rapid analysis of dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO simultaneously2 -And NO3 -The method of (1) is characterized in that dibutyl phosphate (DBP), monobutyl phosphate (MBP), n-butyric acid (n-C) in the organic phase are analyzed simultaneously by ion chromatography3H7COOH), formic acid (HCOOH), NO2 -And NO3 -The method comprises the following steps:
(1)DBP、MBP、n-C3H7COO-、HCOOH、NO2 -and NO3 -Drawing a standard curve:
mixing DBP, MBP, n-C3H7COOH、HCOOH、NaNO2And KNO3Dissolving the standard in ultrapure water, and using DBP, MBP, n-C as required3H7COOH、HCOOH、NaNO2And KNO3Diluting the standard solution into standard test solutions with different concentrations as DBP, MBP and n-C3H7COOH、HCOOH、NaNO2And KNO3Characterizing the sample solution by applying different concentrations of DBP, MBP, n-C3H7COOH、HCOOH、NaNO2And KNO3Analyzing the characteristic sample solution by ion chromatography to obtain DBP, MBP, n-C3H7COOH、HCOOH、NaNO2And KNO3The ion chromatogram standard spectrogram of the characteristic sample solution and the peak areas of the corresponding components are respectively represented by DBP, MBP and n-C3H7COO-、HCOO-、NO2 -And NO3 -The concentration is the abscissa, the corresponding peak area is the ordinate, and DBP, MBP and n-C are drawn3H7COO-、HCOO-、NO2 -And NO3 -Standard working curve:
Y＝aX+b；
wherein: x is DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The molar concentration of the solution, Y is the corresponding peak area, and a and b are dimensionless coefficients;
(2) carrying out pretreatment on a sample to be detected to prepare a sample extracting solution to be detected:
taking 25mL of sample to be detected into a 50mL centrifuge tube, then putting the centrifuge tube into a centrifuge, and centrifuging for at least 5min at the rotating speed of not less than 3000 rpm; then taking 2mL of the upper organic phase to another centrifugal tube with the volume not less than 13mL, adding 10mL of Na2CO3Mixing the centrifugal tube with NaOH to obtain a mixed aqueous solution, then placing the centrifugal tube into a turbine oscillator, oscillating at a rotating speed of not less than 2300rpm for at least 5min to fully mix, back-extract and elute; then, putting the centrifugal tube into a centrifuge, centrifuging for at least 5min at the rotating speed of not less than 2000rpm, taking the lower-layer water phase for diluting, and taking the diluted lower-layer water phase as a sample extracting solution to be detected;
(3) and (3) analyzing the extract of the sample to be detected by ion chromatography:
DBP, MBP, n-C in step (1)3H7COOH、HCOOH、NaNO2And KNO3Under the condition that the characteristic sample solution analysis is the same, carrying out ion chromatography analysis on the extracting solution of the sample to be detected obtained in the step (2) to obtain DBP, MBP and n-C in the extracting solution of the sample to be detected3H7COO-、HCOO-、NO2 -And NO3 -By using the peak area of DBP, MBP, n-C obtained in the step (1)3H7COO-、HCOO-、NO2 -And NO3 -Calculating to obtain DBP, MBP and n-C in the extract of the sample to be detected according to a standard working curve3H7COO-、HCOO-、NO2 -And NO3 -And (4) concentration.
2. The method according to claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate,N-butyric acid, formic acid, NO2 -And NO3 -The method of (2), characterized by: in the step (1), DBP, MBP, n-C are subjected to3H7COOH、HCOOH、NaNO2And KNO3The conditions for performing the ion chromatography analysis on the characteristic sample solution are the same as the conditions for performing the ion chromatography analysis on the extract liquid of the sample to be measured in the step (3).
3. The method of claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2 -And NO3 -The method of (2), characterized by: in the step (1), DBP, MBP, n-C are subjected to3H7COOH、HCOOH、NaNO2And KNO3The conditions for ion chromatography analysis of the characteristic sample solution were as follows:
a. a chromatographic column: AS11-HC (4X 250 mm);
b. sample introduction amount: 25 mu L of the solution;
c. gradient of leacheate:
d. flow rate gradient:
e. column temperature: 30 ℃;
f. a detector: a conductivity detector.
4. The method of claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2 -And NO3 -The method of (2), characterized by: in the step (3), the conditions for performing ion chromatography analysis on the sample extract to be tested are as follows:
a. a chromatographic column: AS11-HC (4X 250 mm);
b. sample introduction amount: 25 mu L of the solution;
c. gradient of leacheate:
d. flow rate gradient:
e. column temperature: 30 ℃;
f. a detector: a conductivity detector.
5. The method of claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2 -And NO3 -The method of (2), characterized by: DBP, MBP, n-C in the sample extract to be tested3H7COOH、HCOOH、NaNO2And KNO3The minimum detection concentration of the assay is not less than 1 × 10-7mol·L-1、8×10-7mol·L-1、5×10-8mol·L-1、5×10- 8mol·L-1、5×10-8mol·L-1And 5X 10-8mol·L-1。
6. The method of claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2 -And NO3 -The method of (2), characterized by: DBP, MBP, n-C in the sample extract to be tested3H7COOH、HCOOH、NaNO2And KNO3The relative standard deviations of the analyses were not higher than 2.6%, 3.8%, 3.7%, 1.5%, 1.7% and 2.0%, respectively.
7. The method of claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2 -And NO3 -The method of (2), characterized by: and (3) performing ion chromatography analysis in the step (1) and the step (3) to obtain eluate with elution time or sample peak retention time not exceeding 30 min.
8. The method of claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2 -And NO3 -The method of (2), characterized by: in the step (2), the organic phase is subjected to back extraction elution and centrifugal separation by carrying out pretreatment on the sample to be detected, a lower-layer water phase is extracted, and a set multiple is diluted to obtain a sample extracting solution to be detected; then, in the step (3), DBP, MBP and n-C contained in the extracting solution of the sample to be detected are obtained through the ion chromatogram of the sample to be detected3H7COO-、HCOO-、NO2 -And NO3 -According to the area of the peak of DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The standard curve and the dilution multiple of the extracting solution of the sample to be detected are prepared, and DBP, MBP and n-C in the extracting solution of the sample to be detected are calculated3H7COO-、HCOO-、NO2 -And NO3 -The concentration of (c).
9. The method of claim 1 for simultaneously and rapidly analyzing dibutyl phosphate, monobutyl phosphate, n-butyric acid, formic acid and NO2 -And NO3 -The method of (2), characterized by: in the step (2), in Na2CO3Mixed with NaOH aqueous solution, Na2CO3The mass percent concentration is 1 wt.%, and the mass percent concentration of NaOH is 1 wt.%.
Technical Field
The invention relates to an analysis method for simultaneously and rapidly analyzing six ions, in particular to a qualitative and quantitative analysis method for coexistence of ester, organic acid, inorganic acid and inorganic acid salt in a complex phase, belonging to the technical field of analytical chemistry.
Background
In order to solve the problem of serious environmental pollution caused by long-term use of fossil fuels, China is vigorously developing nuclear power and clean energy. However, the rapid development of nuclear power will produce a large amount of spent fuel. In a high-level radioactive waste liquid evaporation and concentration system of a spent fuel post-treatment process, tributyl phosphate (TBP) is irradiated or nitric acid in the system is acted, so that dibutyl phosphate (DBP), monobutyl phosphate (MBP) and n-butyl alcohol are decomposed to generate dibutyl phosphate (DBP), the n-butyl alcohol is oxidized into n-butyl acid (n-C) by nitric acid3H7COOH), nitric acid decomposition produces NO2 -. In addition, since the denitration agent formaldehyde is added to the evaporation concentration system for denitration, formaldehyde is oxidized into formic acid (HCOOH). Thus, the system has DBP, MBP, n-C3H7COOH、HCOOH、NO2 -And NO3 -These substances may interfere with the proper operation of the process, and their concentration needs to be accurately analyzed.
In order to rapidly analyze these substances, it is desired to simultaneously analyze them, and since there is no literature report on a method for simultaneously analyzing these substances at home and abroad, it is necessary to establish a method for simultaneously analyzing DBP, MBP, n-C in an organic phase3H7COO-、HCOO-、NO2 -And NO3 -This is becoming a technical problem to be solved urgently.
Disclosure of Invention
In order to solve the problems of the prior art, the invention aims to overcome the defects of the prior art and provide a method for simultaneously and rapidly analyzing DBP, MBP and n-C3H7COO-、HCOO-、NO2 -And NO3 -The method of (1) can simultaneously and rapidly analyze DBP, MBP and n-C in the organic phase by taking the organic phase as an analysis target3H7COO-、HCOO-、NO2 -And NO3 -。DBP、MBP、n-C3H7COO-、HCOO-、NO2 -And NO3 -The lowest detection concentrations of the assays were 1X 10, respectively-7、8×10-7、5×10-8、5×10-8、5×10-8And 5X 10- 8mol·L-1The relative standard deviations of the analyses were 2.6%, 3.8%, 3.7%, 1.5%, 1.7% and 2.0%, respectively. High sensitivity, low detection limit and good repeatability.
In order to achieve the purpose of the invention, the invention adopts the following technical scheme:
rapid analysis of DBP, MBP, n-C in organic phase simultaneously3H7COO-、HCOO-、NO2 -And NO3 -The method is characterized in that DBP, MBP and n-C in the organic phase are simultaneously analyzed by ion chromatography3H7COOH、HCOOH、NO2 -And NO3 -The method comprises the following steps:
(1)DBP、MBP、n-C3H7COO-、HCOOH、NO2 -and NO3 -Drawing a standard curve:
mixing DBP, MBP, n-C3H7COOH、HCOOH、NaNO2And KNO3Dissolving the standard in ultrapure water, and using DBP, MBP, n-C as required3H7COOH、HCOOH、NaNO2And KNO3Diluting the standard solution into standard test solutions with different concentrations as DBP, MBP and n-C3H7COOH、HCOOH、NaNO2And KNO3Characterizing the sample solution by applying different concentrations of DBP, MBP, n-C3H7COOH、HCOOH、NaNO2And KNO3Analyzing the characteristic sample solution by ion chromatography to obtain DBP, MBP, n-C3H7COOH、HCOOH、NaNO2And KNO3Ion chromatography standard spectrogram of characteristic sample solution and corresponding components DBP, MBP and n-C3H7COO-、HCOOH、NO2 -And NO3 -The peak areas of (a) are respectively DBP, MBP and n-C3H7COO-、HCOO-、NO2 -And NO3 -The concentration is the abscissa, the corresponding peak area is the ordinate, and DBP, MBP and n-C are drawn3H7COO-、HCOO-、NO2 -And NO3 -Standard working curve:
Y＝aX+b；
wherein: x is DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The molar concentration of the solution, Y is the corresponding peak area, and a and b are dimensionless coefficients;
(2) carrying out pretreatment on a sample to be detected to prepare a sample extracting solution to be detected:
taking 25mL of sample to be detected into a 50mL centrifuge tube, then putting the centrifuge tube into a centrifuge, and centrifuging for at least 5min at the rotating speed of not less than 3000 rpm; then taking 2mL of the upper organic phase to another centrifugal tube with the volume not less than 13mL, adding 10mL of Na2CO3An aqueous solution mixed with NaOH; then, againPlacing the centrifugal tube on a turbine oscillator, oscillating at a rotation speed of not less than 2300rpm for at least 5min to fully mix, back-extract and elute; then, putting the centrifugal tube into a centrifuge, centrifuging for at least 5min at the rotating speed of not less than 2000rpm, taking the lower-layer water phase for diluting, and taking the diluted lower-layer water phase as a sample extracting solution to be detected; preferably, in Na2CO3Mixed with NaOH aqueous solution, Na2CO3The mass percent concentration is 1 wt.%, and the NaOH mass percent concentration is 1 wt.%;
(3) and (3) analyzing the extract of the sample to be detected by ion chromatography:
DBP, MBP, n-C in step (1)3H7COOH、HCOOH、NaNO2And KNO3Under the condition that the characteristic sample solution analysis is the same, carrying out ion chromatography analysis on the extracting solution of the sample to be detected obtained in the step (2) to obtain DBP, MBP and n-C in the extracting solution of the sample to be detected3H7COO-、HCOO-、NO2 -And NO3 -By using the peak area of DBP, MBP, n-C obtained in the step (1)3H7COO-、HCOO-、NO2 -And NO3 -Calculating to obtain DBP, MBP and n-C in the extract of the sample to be detected according to a standard working curve3H7COO-、HCOO-、NO2 -And NO3 -And (4) concentration.
Preferably, DBP, MBP, n-C are treated in said step (1)3H7COOH、HCOOH、NaNO2And KNO3The conditions for performing the ion chromatography analysis on the characteristic sample solution are the same as the conditions for performing the ion chromatography analysis on the extract liquid of the sample to be measured in the step (3).
Preferably, in said step (1), DBP, MBP, n-C are treated3H7COOH、HCOOH、NaNO2And KNO3The conditions for ion chromatography analysis of the characteristic sample solution were as follows:
a. a chromatographic column: AS11-HC (4X 250 mm);
b. sample introduction amount: 25 mu L of the solution;
c. gradient of leacheate:
d. flow rate gradient:
e. column temperature: 30 ℃;
f. a detector: a conductivity detector.
Preferably, in the step (3), the conditions for performing ion chromatography analysis on the sample extract to be tested are as follows:
a. a chromatographic column: AS11-HC (4X 250 mm);
b. sample introduction amount: 25 mu L of the solution;
c. gradient of leacheate:
d. flow rate gradient:
e. column temperature: 30 ℃;
f. a detector: a conductivity detector.
Preferably, DBP, MBP and n-C in the extract of the sample to be detected3H7COOH、HCOOH、NaNO2And KNO3The minimum detection concentration of the assay is not less than 1 × 10-7mol·L-1、8×10-7mol·L-1、5×10-8mol·L-1、5×10-8mol·L-1、5×10-8mol·L-1And 5X 10-8mol·L-1。
Preferably, DBP, MBP and n-C in the extract of the sample to be detected3H7COOH、HCOOH、NaNO2And KNO3The relative standard deviations of the analyses were not higher than 2.6%, 3.8%, 3.7%, 1.5%, 1.7% and 2.0%, respectively.
Preferably, the elution time or the peak retention time of the sample for the ion chromatography analysis in said step (1) and step (3) does not exceed 30 min.
Preferably, in the step (2), the sample to be detected is pretreated to perform back extraction elution and centrifugal separation on the organic phase, the lower aqueous phase is extracted, and the sample to be detected extract is obtained by diluting with a set multiple; then, in the step (3), DBP, MBP and n-C contained in the extracting solution of the sample to be detected are obtained through the ion chromatogram of the sample to be detected3H7COO-、HCOO-、NO2 -And NO3 -According to the area of the peak of DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The standard curve and the dilution multiple of the extracting solution of the sample to be detected are prepared, and DBP, MBP and n-C in the extracting solution of the sample to be detected are calculated3H7COO-、HCOO-、NO2 -And NO3 -The concentration of (c).
Compared with the prior art, the invention has the following obvious and prominent substantive characteristics and remarkable advantages:
1. the invention adopts ion chromatography, uses an eluent gradient method and a flow velocity gradient method, and can carry out the treatment on DBP, MBP and n-C in a complex phase3H7COO-、HCOO-、NO2 -And NO3 -Performing simultaneous and rapid analysis;
2. the method has the advantages of high analysis speed, low detection limit, high sensitivity and good repeatability;
3. the method is easy to operate, low in cost and suitable for popularization and use.
Drawings
FIG. 1 is 2X 10-5mol·L-1DBP、MBP、n-C3H7COO-、HCOO-、NO2 -And NO3 -And (5) ion chromatogram of the characteristic sample mixed solution. In the figure, the abscissa is time (min) and the ordinate is peak height (mv). DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The retention time of (A) is 23.13min, 21.81min, 7.56min, 6.12min, 19.22min and 26.58min respectively.
Fig. 2 is an operation curve of a DBP plotted according to a preferred embodiment 1 of the present invention. The abscissa is the DBP concentration (10)-4mol·L-1) The ordinate is the peak area (mv · s) of DBP. Working curve: Y-2.125X-0.304; coefficient of correlation R2：R2＝1.000。
FIG. 3 is a graph of the MBP operation plotted in accordance with the preferred embodiment 1 of the present invention. The abscissa is MBP concentration (10)-6mol·L-1) The ordinate is the peak area of MBP (mv. s). Working curve: y ═ 0.305X; r2＝0.995。
FIG. 4 is a drawing of n-C according to the preferred embodiment 1 of the present invention3H7COO-The operating curve of (c). The abscissa is n-C3H7COO-Concentration (10)-6mol·L-1) Ordinate is n-C3H7COO-Peak area (mv · s). Working curve: y ═ 2.135X; r2＝0.998。
FIG. 5 is a diagram of HCOO plotted according to the preferred embodiment 1 of the present invention-The operating curve of (c). The abscissa is HCOO-Concentration (10)- 6mol·L-1) Ordinate is HCOO-Peak area (mv · s). Working curve: y is 0.483X; r2＝0.999。
FIG. 6 is a drawing of NO according to the preferred embodiment 1 of the present invention2 -The operating curve of (c). Abscissa of NO2 -Concentration (10)-6mol·L-1) Ordinate is NO3 -Peak area (mv · s). Working curve: y ═ 0.226X-0.033; r2＝0.999。
FIG. 7 is a drawing of NO according to the preferred embodiment 1 of the present invention3 -The operating curve of (c). Abscissa of NO3 -Concentration (10)-2mol·L-1) Ordinate is NO2 -Peak area (mv · s). Working curve: Y-2.731X-0.079; r2＝1.000。
FIG. 8 shows the results of the preferred embodiment 1 of the present invention at 100 ℃ after addition of formaldehyde，0.45g·L-1Ce3+-30％NaNO3-TBP-4mol·L-1HNO3(the volume ratio of the water phase to the organic phase is 9:1) reacting for 10 hours. In the figure, the abscissa is time (min) and the ordinate is peak height (mv).
Detailed Description
The above-described scheme is further illustrated below with reference to specific embodiments, which are detailed below:
example 1
In this example, ion chromatography was used to simultaneously analyze DBP, MBP, n-C, referring to FIGS. 1-83H7COO-、HCOO-、NO2 -And NO3 -The method comprises the following steps:
(1) preparation of standard solution:
0.1734g DBP, 0.2496g MBP, 0.0712g n-C were weighed out separately3H7COOH、0.0375g HCOOH、0.0558gNaNO2And 0.0817g KNO3Adding ultrapure water into a 10mL volumetric flask for dissolving and diluting to scale marks, shaking uniformly, and respectively preparing into 8 × 10-2mol·L-1DBP、MBP、n-C3H7COO-、HCOO-、NO2 -And NO3 -Diluting the standard solution into standard solutions with different concentrations according to the needs;
(2)0.45g·L-1Ce3+-30wt.％NaNO3-4 mol·L-1HNO3preparing an aqueous solution:
weighing a certain amount of HNO3Adding a certain amount of cerous nitrate hexahydrate and a certain amount of NaNO into a volumetric flask with a certain volume3Finally, the volume is determined by high-purity water and shaken up.
(3) After formaldehyde addition, 0.45 g.L-1Ce3+-30wt.％NaNO3-TBP-4mol·L-1HNO3Reaction of the system: the rotor was placed in a three-necked flask, and 200mL of 0.45 g.L was added-1Ce3+-30％NaNO3-4.0mol·L-1HNO3And (3) solution. The three openings are arrangedThe flask was put in place in an oil bath, and then the three-necked flask was fixed on an iron stand. Inserting a thermometer with the measuring range of 200 ℃ into the left opening of the three-mouth bottle; the right opening of the three-mouth bottle is provided with a spiral condensing tube. Tap water in a fume hood is opened to ensure condensation and reflux. Heating and stirring the sample by using a heat collection type constant temperature heating magnetic stirrer, turning on a stirring and heating button, and slowly pouring the rest 70mL of 0.45 g.L when the temperature is raised to 50 DEG C-1Ce3+-30wt.％NaNO3-4 mol·L-1HNO3The solution was then added 30mL of neat TBP and the solution was further heated to 100 ℃. When the temperature reaches 100 ℃, adding 5mL of formaldehyde solution with the mass percent concentration of 37 wt.%, then adding 0.5mL of formaldehyde solution every 20min, when the adding time point and the sampling time point of the formaldehyde coincide, firstly sampling and adding the formaldehyde till the reaction is finished, and adding no formaldehyde at the sampling point for 6 h. After reacting for 6h, using a glass rubber head dropper, quickly sampling 25mL of mixture sample as a sample to be detected in a 50mL centrifuge tube at the middle opening of the three-mouth flask, and then putting the centrifuge tube into an ice-water bath for cooling.
(4) Pretreatment of a reaction sample:
and putting the centrifuge tube filled with the sample to be tested into a centrifuge, and centrifuging for 5min at the rotating speed of 3000 rpm. 2mL of the upper organic phase was placed in another 50mL centrifuge tube and 10mL of 1 wt.% Na was added2CO31 wt.% aqueous NaOH, placing the tube in a turbine shaker and shaking at 2300rpm for 5min to mix thoroughly for stripping. Then, placing the centrifugal tube into a centrifuge, centrifuging for 5min at the rotating speed of 3000rpm to separate an organic phase from a water phase, taking a lower-layer water phase, and properly diluting the lower-layer water phase to obtain a sample extracting solution to be detected;
(5) preparation of ion chromatograph: correctly loading an anion chromatographic column into an ion chromatograph, and switching eluent to KOH;
(6) turning on the power supply of the instrument, and lighting an indicator light; opening a computer, and starting Chromeleon 7 software; opening a pump window and clicking Bottom; opening a drip washing liquid generator window, and clicking EG1 control and CR-TC control; open the DC window and click the suppressor-Left. Setting the concentration of the leacheate: 23mmoL L-1(ii) a The flow rate of the leaching solution is 0.4 mL/min-1(ii) a Column temperature: 30 ℃; a base line is taken;
(7) placing the solution to be detected in a sample tray;
(8) when the baseline is stable, selecting an instrument method in the creation window, selecting an instrument as ICS-6000, and clicking the next step; setting the running time to be 30min, and clicking the next step; clicking the type, selecting a multi-step gradient, and clicking the next step; setting a Pump _1 gradient according to the table 1, and clicking the next step; clicking concentration, selecting a multi-step gradient, and clicking the next step; setting the EGC _1 gradient of the leaching solution generator according to the table 2, and clicking the next step; selecting and cleaning, selecting the volume of 1000 mu L, and clicking the next step; checking CD _1 and CD _1_ Total in the channel, and clicking the next step; clicking the suppressor type, selecting AERS _4mm, and clicking the next step; the concentration of hydroxyl group in the eluent concentration was set to 31 mmol.L-1Clicking the next step; clicking and opening in a Column, setting the Column temperature to be 30 ℃, and clicking the next step; completing clicking; and clicking a saving and changing window to save the method.
TABLE 1 elution flow rate gradient Table I
Time (min)
Flow Rate (mL. min)-1)
0
Operation of
3.5
1.0
4.0
0.2
10.0
0.2
11.0
0.4
30.0
Stop running
TABLE 2 gradient comparison of leacheate concentration Table II
Time (min)
Flow Rate (mL. min)-1)
0
Operation of
10.0
10
11.0
31
30.0
Stop running
(9) Selecting a sequence in a creation window; clicking the next step, setting the sampling frequency to be 1 and the sampling amount to be 25 mu L; selecting the created method in the previous step, and clicking the next step; after clicking is finished, saving the sequence; and clicking a start button to start sample injection and simultaneously starting to record data.
(10) After the analysis is finished, entering a qualitative analysis stage and quantitative analysisA stage; adopting a retention time comparison method to compare the retention time of each peak of a spectrogram of a sample to be detected with DBP, MBP and n-C3H7COO-、HCOO-、NO2 -And NO3 -Comparing the mixed standard sample spectrograms so as to determine whether the sample to be detected contains DBP, MBP and n-C3H7COO-、HCOO-、NO2 -And NO3 -(ii) a The quantitative analysis adopts an external standard method, namely a quantitative sample introduction-working curve method; the quantitative sample introduction-working curve method comprises the following steps: under the same operation conditions, a series of DBP, MBP and n-C with different concentrations are respectively injected into the sample by an automatic sample injector in a quantitative mode3H7COO-、HCOO-、NO2 -And NO3 -Obtaining the peak area of each component, and then respectively drawing a DBP peak area-DBP concentration diagram, an MBP peak area-MBP concentration diagram and n-C3H7COO-Peak area-n-C3H7COO-Concentration map, HCOO-Peak area-HCOO-Concentration diagram, NO2 -Peak area-NO2 -Concentration profile and NO3 -Peak area-NO3 -Concentration profiles, i.e. DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The working curve of (a); under the same analysis conditions, quantitatively injecting a sample to be analyzed; if the sample contains DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -DBP, MBP, n-C appeared around 23.13min, 21.81min, 7.56min, 6.12min, 19.22min and 26.58min, respectively3H7COO-、HCOO-、NO2 -And NO3 -A peak; according to DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The DBP, MBP and n-C in the sample to be measured can be calculated by utilizing the working curve and the dilution multiple of the sample3H7COO-、HCOO-、NO2 -And NO3 -The concentration of (c).
In this example, the data is obtained by applying DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -Analyzing the mixed characteristic sample solution by ion chromatography to obtain DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -See fig. 1 for a mixed ion chromatography standard spectrum. The ion chromatogram of the sample extract to be tested is obtained by analyzing the sample extract to be tested by ion chromatography, see fig. 8. Comparing the chromatogram of the graph with that of the standard mixed sample can be seen that: the sample contains DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -. And (3) drawing a DBP standard working curve by taking the DBP concentration as an abscissa and the corresponding peak area as an ordinate: Y2.125X-0.304, correlation coefficient (R)2)：R21.000, see fig. 2; and (3) drawing an MBP standard working curve by taking the concentration of the MBP as an abscissa and the corresponding peak area as an ordinate: y is 0.305X, R20.995, see fig. 3; with n-C3H7COO-The concentration is the abscissa and the corresponding peak area is the ordinate, and n-C is plotted3H7COO-Standard working curve: y is 2.135X, R20.998, see fig. 4; with HCOO-The concentration is the abscissa and the corresponding peak area is the ordinate, and the HCOO is plotted-Standard working curve: y is 0.483X, R20.999, see fig. 5; with NO2 -The concentration is plotted as abscissa and the corresponding peak area is plotted as ordinate3 -Standard working curve: y is 0.226X-0.033, R20.999, see fig. 6; with NO3 -The concentration is plotted as abscissa and the corresponding peak area is plotted as ordinate3 -Standard working curve: Y-2.731X-0.079, R21.000, see fig. 7; wherein X is DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The concentration of the solution is 10-4、10-6、10-6、10-6、10-6And 10-2mol·L-1(ii) a Y is the corresponding peak area in mv s.
DBP, MBP and n-C contained in the sample to be detected can be obtained through the ion chromatogram of the sample to be detected, see figure 83H7COO-、HCOO-、NO2 -And NO3 -Peak area of (a). Then, based on DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -The standard curve and the dilution multiple of the sample are used for calculating DBP, MBP and n-C in the sample to be detected3H7COO-、HCOO-、NO2 -And NO3 -The concentration of (c). The results are as follows:
TABLE 3 comparison table of corresponding peak components, peak areas and concentrations of ion chromatogram of sample to be detected
The embodiment can realize the DBP, MBP and n-C in the complex phase3H7COO-、HCOO-、NO2 -And NO3 -And carrying out simultaneous, rapid and accurate qualitative and quantitative analysis.
Example two
This embodiment is substantially the same as the first embodiment, and is characterized in that:
in this example, DBP, MBP, n-C in the extract of the sample to be tested3H7COOH、HCOOH、NaNO2And KNO3The minimum detection concentration of the analysis can reach 1 × 10-7mol·L-1、8×10-7mol·L-1、5×10-8mol·L-1、5×10-8mol·L-1、5×10-8mol·L-1And 5X 10-8mol·L-1. To the sample to be measuredExtracting DBP, MBP, n-C in the solution3H7COOH、HCOOH、NaNO2And KNO3The relative standard deviations of the analyses were able to reach 2.6%, 3.8%, 3.7%, 1.5%, 1.7% and 2.0%, respectively.
This example provides a simultaneous and rapid analysis of dibutyl phosphate (DBP), monobutyl phosphate (MBP), n-C in an organic phase3H7COO-、HCOO-、NO2 -And NO3 -The method comprises the following steps: firstly DBP, MBP, n-C3H7COOH、HCOOH、NaNO2And KNO3Dissolving the standard substance in pure water to obtain standard stock solution, preparing sample solutions with different concentrations, analyzing by ion chromatography to obtain ion chromatography standard spectrogram and peak areas of corresponding components, and drawing DBP, MBP, n-C3H7COO-、HCOO-、NO2 -And NO3 -A standard working curve; centrifuging the sample to be tested, extracting the upper organic phase, and using a quantitative 1 wt.% Na2CO3-1 wt.% NaOH aqueous solution is used to back-extract and elute a certain amount of the separated organic phase, and then the organic phase is centrifuged to extract the lower aqueous phase and diluted properly; then carrying out ion chromatography analysis under the same analysis conditions of the ion chromatography to obtain peak areas of corresponding components in the ion chromatogram of the extracting solution of the sample to be detected, and calculating to obtain DBP, MBP and n-C in the organic phase of the sample to be detected by using the standard working curve and the dilution multiple of the sample to be detected3H7COO-、HCOO-、NO2 -And NO3 -And (4) concentration. The invention adopts ion chromatography, and can simultaneously and rapidly analyze DBP, MBP and n-C in the organic phase3H7COO-、HCOO-、NO2 -And NO3 -High sensitivity, low detection limit and good repeatability.
The embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the embodiments, and various changes and modifications can be made according to the purpose of the invention, and any changes, modifications, substitutions, combinations or simplifications made according to the spirit and principle of the technical solution of the present invention shall be equivalent substitutions, as long as the purpose of the present invention is met, and the present invention shall fall within the protection scope of the present invention without departing from the technical principle and inventive concept of the present invention.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：一种用于拍摄过载条件下固体推进剂燃烧试验的装置