CN105606721B

CN105606721B - The method of separating and assaying of arsenic in a kind of PM2.5

Info

Publication number: CN105606721B
Application number: CN201510915345.4A
Authority: CN
Inventors: 尹西翔; 王利红; 于雄军; 栾玲玉; 韩术鑫
Original assignee: JINAN RESEARCH INSTITUTE OF ENVIRONMENTAL PROTECTION; Shandong Analysis and Test Center
Current assignee: JINAN RESEARCH INSTITUTE OF ENVIRONMENTAL PROTECTION; Shandong Analysis and Test Center
Priority date: 2015-12-11
Filing date: 2015-12-11
Publication date: 2017-10-31
Anticipated expiration: 2035-12-11
Also published as: CN105606721A

Abstract

The invention provides a kind of method of separating and assaying of arsenic in PM2.5, it is using 1% nitric acid as extractant, and high performance liquid chromatography inductively coupled plasma mass spectrometer coupling is extracted and determined with to arsenic morphology in PM2.5.This method can realize being kept completely separate for different shape arsenic in 4,4 kinds of arsenic morphologies in 10 minutes：Trivalent arsenic (As (III)), pentavalent arsenic (As (V)), the method detection limit of monomethyl arsenic (MMA) and dimethyl arsenic (DMA) are in 0.6~1 μ gL^‑1Between, As (III), DMA, MMA, As (V) precision are respectively not occur substantially conversion in 1.26%, 1.24%, 1.00%, 0.79%, continuous mode between each form arsenic.

Description

The method of separating and assaying of arsenic in a kind of PM2.5

Technical field

The invention discloses a kind of method for detecting atmosphere pollution, a kind of point of arsenic in detection PM2.5 is specifically disclosed From assay method.

Background technology

Arsenic is the metalloid element being widely present in environment, and its mean concentration in the earth's crust is in 4.8 ± 0.5 mg kg^-1。 Arsenic in environment mainly has natural way and mankind's activity two to originate greatly, and volcano eruption is the Major Natural source of arsenic, ore combustion Burning, metal smelt and the use of the herbicide containing arsenic of material are the main artificial sources of arsenic in global atmosphere.Arsenic element is with a variety of The form of different compounds exists in the environment.The physico-chemical property of different shape arsenic compound is different, generally believes inorganic arsenic Toxicity is better than organo-arsenic, and As (III) toxicity is significantly larger than As (V), and the migrations of As (III) in the environment are more than As (V).Therefore, the analysis of arsenic morphology has weight to arsenic compound toxicological effect in the environment and human health risk evaluation study The meaning wanted.

Atmospheric particulates are that human body takes in another important sources of arsenic, European Union 2004/107 after after food and drinking water Criterion is 6 ngm to the limitation of arsenic concentration in air^-3.Current research shows between 2009-2011 arsenic in China city TSP Average content is 130.00 ngm^-3, more than more than 20 times of EU criteria, and arsenic in Atmospheric particulates is with the larger As of toxicity (III), based on As (V).Existing research focuses primarily upon Atmospheric particulates TSP, PM₁₀, arsenic macroanalysis in PM2.5, on Arsenium morphological analysis correlative study is relatively limited in particulate matter, and the analysis particularly with arsenic morphology in PM2.5 is rarely reported.

The content of the invention

In order to solve the above technical problems, the invention provides a kind of method of separating and assaying of arsenic in PM2.5.

The present invention is achieved by the following technical solutions：

The method of separating and assaying of arsenic, comprises the following steps in a kind of PM2.5：

1）Sampled using 25cm*20cm glass fiber filters；

2）1/4 filter membrane of clip is shredded into 50 mL centrifuge tube, adds 1% HNO₃Solution 5mL, vibration is mixed；Will Solution, which is transferred in polypropylene counteracting tank, carries out micro-wave digestion, clears up program：55 DEG C of -10 min, 75 DEG C of -10 min, 90 DEG C -30 Min, power setting is 1200 W；Room temperature is cooled to after clearing up end, 10 min will be centrifuged under the rpm of digestion solution 5000, supernatant is taken Liquid adds 1% HNO into 50 mL centrifuge tubes₃It is settled to 15 mL；- 80 DEG C are stored in, to high performance liquid chromatography-inductive Plasma mass spectrograph separation determination；

Separation condition：With 10 mmolL^-1NH₄NO₃, (NH₄)₂HPO₄Mixed solution is mobile phase, uses HNO₃Adjust pH To 6.2.Mobile phase is by 0.45 μm of filter membrane, in case the speed of mobile phase is 1 in contaminated samples splitter, separation process mL·min^-1, each μ L of sample introduction 100.

At present, China is with particulate matter particularly fine particle（PM2.5）The regional compound atmosphere pollution being characterized is asked Topic becomes increasingly conspicuous, and the health effect research of noxious material turns into the study hotspot in atmospheric science in PM2.5.The present invention is set up 1%HNO₃Extract, the method that HPLC-ICP-MS combinations determine each arsenic morphology in PM2.5, this method extractant acidity is small, environment Close friend, is adapted to ICP-MS measure, and method detection limit, precision can preferably meet wanting for Atmospheric particulates arsenic morphology measure Ask, and do not occur substantially conversion in continuous mode between each form.

Brief description of the drawings

Fig. 1 is detection collection of illustrative plates of the invention.

Fig. 2 is the separation chromatography figure that blank filter membrane adds arsenic standard solution.

Embodiment

With reference to embodiment to further instruction of the present invention.

Embodiment 1

1）Sampled using 25cm*20cm glass fiber filters；

Specific chromatogram such as Fig. 1, it will be seen from figure 1 that detecting As (III) and As (V), DMA and MMA in filter membrane Do not detect, this mainly exists consistent with arsenic in Atmospheric particulates in prior art data with As (V) and As (III) form.

Checking test

1）The selection of extractant

H₃PO₄, NH₂OH.HCl is often used as the extractant of arsenic compound in Atmospheric particulates.H₃PO₄It is main as middle strong acid Will by way of substitution by arsenic from compound extracts solution, but extract solution is acid stronger, and viscosity is larger, can be to ICP- MS stability causes certain influence.Higher concentration NH₂OH.HCl can also bring a large amount of Cl ions into extraction process, be given birth to Ar Into⁴⁰Ar³⁷Cl⁺, the measure to arsenic interferes.The HNO of low concentration₃As a kind of gentle extractant, surveyed in HPLC-ICP-MS Determine to have reported in rice, algae arsenic morphology, but it has not been reported in terms of Atmospheric particulates arsenic morphology extraction.This research is led to Cross and set different concentration gradients to be pre-processed, the final HNO determined using 1%₃As extractant to arsenic morphology in PM2.5 Analyzed.From table 1, extracted using 1% nitric acid, HPLC-ICP-MS determines adding and and atom fluorimetry for each arsenic morphology Total arsenic content compare, the rate of recovery is between 91.8 ~ 100.5%, it is seen that the processing can fully extract each form arsenic in PM2.5.

The nitric acid of table 1 1% extracts the rate of recovery that HPLC-ICP-MS determines each arsenic morphology

2）Detection limit and precision test

The measure of each form arsenic detection limit and precision, blank filter are carried out by the way of blank filter membrane adds arsenic standard solution Film adds 10 μ gL^-1The mixed standard solution of arsenic morphology is measured after being extracted through 1% nitric acid using the inventive method.Such as Fig. 2 institutes Show, being kept completely separate for 4 kinds of different shape arsenic, mutual noiseless, good separation can be realized in 10 min.

Using the mode of blank filter membrane mark-on, accurately prepare a series of arsenic morphologies mixed standard solution (1,5,10,20, 50、100 μg·L^-1), the range of linearity and detection limit of 4 kinds of arsenic morphologies of measure are (with 3 times of signal to noise ratio under the experiment condition of optimization S/N is calculated), as a result as shown in table 2.In 1 ~ 100 μ gL^-1In the range of linearity, obtained curve correlation coefficient r²It is all higher than 0.999, As (III), DMA, MMA, As (V) detection limit are in 0.6 ~ 1 μ gL^-1Between.

Working curve, the range of linearity and the detection limit of the detection method of table 2

Arsenic content status in actual sample, selection blank filter membrane adds 10 μ gL^-1The mode of arsenic standard solution is entered The measure of row sample precision.Analog sample METHOD FOR CONTINUOUS DETERMINATION 7 times, calculates the measure precision of each form arsenic respectively.As(III)、 DMA, MMA, As (V) precision are respectively 1.26%, 1.24%, 1.00%, 0.79%.

3）Sample recovery of standard addition

Recovery testu is carried out to actual filter membrane sample with the inventive method, each form arsenic carrying in extraction process is examined Take efficiency and whether occur Forms Transformation.The ngm of mark-on amount 5^-3, assay is shown in Table 3.As (III) in sample, DMA, MMA, As (V) concentration are respectively 6.53,0,0,8.00 ngm^-3, measured value is respectively 10.9,4.72,4.84 after mark-on, 12.9 ng·m^-3, the recovery of standard addition for obtaining actual sample is 87.4~98.0%.As can be seen here, in sample extraction and measure During do not occur substantially conversion between 4 kinds of arsenic morphologies.

Arsenic morphology measured value and recovery of standard addition in the PM2.5 of table 3.（n=3）

ND：Expression is not detected (Not detected).

Claims

1. the method for separating and assaying of arsenic morphology in a kind of PM2.5, it is characterised in that comprise the following steps：1）Using glass fibre Filter membrane is sampled；2）1/4 filter membrane of clip is shredded into 50mL centrifuge tube, adds 1% HNO3 solution 5mL, and vibration is mixed It is even；Solution is transferred in polypropylene counteracting tank and carries out micro-wave digestion, program is cleared up：55 DEG C of -10min, 75 DEG C of -10min, 90 DEG C - 30min, power setting is 1200W；Room temperature is cooled to after clearing up end, 10min will be centrifuged under digestion solution 5000rpm, supernatant is taken Liquid is into 50mL centrifuge tubes, and the HNO3 for adding 1% is settled to 15mL；- 80 DEG C are stored in, to high performance liquid chromatography-inductive Plasma mass spectrograph separation determination；Separation condition：With 10mmolL-1 NH4NO3, (NH4) 2HPO4 mixed solutions are stream Dynamic phase, pH to 6.2 is adjusted with HNO3, and mobile phase is by 0.45 μm of filter membrane, in order to avoid contaminated samples splitter, in separation process The speed of mobile phase is 1mLmin-1, each μ L of sample introduction 100.