Aniline compounds, which are a class of semi-volatile organic compounds (SVOCs), are widely used in the chemical, printing, dyeing and pharmaceutical industries. This type of compound has a large amount and is prone to residue, and is an important component of toxic and hazardous waste water in industrial environments. Countries such as the European Union, the United States, and Japan have listed aniline compounds as their main or priority pollutants. In 2017, the Ministry of Environmental Protection of the People's Republic of China formally issued the “HJ 822-2017 Water Chromatography Mass Spectrometry Method for the Determination of Aniline Compounds”, which was formally implemented on May 1 of that year.

Tianrui Instrument has always been committed to providing customers with complete solutions, GC-MS 6800 can be used for the determination of aniline compounds in water.

1. Introduction of the instrument

GC-MS 6800 is a cost-effective gas chromatograph mass spectrometry instrument carefully crafted by Skyray Instruments. It has complete independent intellectual property rights and has a number of patented technologies that can be widely used in polymer materials, environmental protection, electronic appliances, and pharmaceuticals. , Detection of hazardous substances in many industries such as petrochemicals, food safety, textiles and leather.

Figure 1. Appearance of a GC-MS 6800 Gas Chromatograph Mass Spectrometer

2 experimental part

2.1 Reference Standard

"HJ 822-2017 Determination of Aniline Compounds by Gas Chromatography-Mass Spectrometry"

2.2 Test principle

The aniline compounds in the water sample were extracted with dichloromethane under the condition of pH≥11. The extract was dehydrated, concentrated and purified and then determined by gas chromatography-mass spectrometry. Based on the retention time of the target compound and the standard mass spectrometry and characteristic ion quantification, quantification was performed using the internal standard method.

2.3 Major Equipment, Consumables, and Reagents

GC-MS 6800 Gas Chromatography-Mass Spectrometer (Jiangsu Tianrui Instrument Co., Ltd.)

Column: DB-5MS 30m*0.25mm*0.25μm (Agilent Technologies)

Rotary Concentrator (Shanghai Arong Biochemical Instrument Factory, RE-52)

Nitrogen blowing instrument (Beijing U-Technology Co., Ltd., UGC-12WF)

Solid phase extraction device (adjustable flow rate by vacuum pump) (Supelco, 12 digits)

Florisil column: 1000 mg/6 ml, commercially available

Micropipette 50μl, 100μl, 1000μl

Separation funnel 1L or 2L

Dichloromethane (CH2Cl2): HPLC grade, isopropyl alcohol (C3H8O): HPLC grade, n-hexane (C6H14): HPLC grade

Methanol (CH3OH): HPLC grade, sodium thiosulfate (Na2S2O3): analytical grade, sodium chloride (NaCl): analytical grade,

Anhydrous sodium sulfate (Na2SO4): analytical grade, sodium hydroxide solution: c (NaOH) = 10 mol/L, sulfuric acid solution: 1+1

Standard stock solution of aniline compound: ρ=1000μg/ml, containing 19 target compounds

Alternative (4-bromofluorobenzene) standard stock solution: ρ = 2000 μg/ml

Internal standard (1,2-dichlorobenzene-d4, phenanthrene-d10) stock solution: ρ=2000 μg/ml

2.4 Instrument Test Conditions

Column: DB-5MS, 30m × 0.25mm × 0.25μm

The oven temperature program: 50°C (1min) 10°C/min 280°C (5min)

Inlet temperature: 280°C; temperament interface temperature: 280°C; ion source temperature: 280°C;

Carrier gas: helium, purity ≥99.999%, flow rate 1.0ml/min

Ionization method: EI; Ionization energy: 70 eV

Injection mode: split injection, split ratio 5:1, injection volume: 1.0μl

Measurement method: TIC (FULL SCAN) qualitative (scan range: 45 to 500 amu), SIM mode quantification

Figure 2. Total ion chromatograms of aniline compounds

1, 4-bromofluorobenzene 2, aniline 3, 1,2-dichlorobenzene-d4 4, 2-chloroaniline 5, 3-chloroaniline 6, 4-chloroaniline 7, 4-bromoaniline 8, 2-nitrate Benzaldehyde 9,2,4,6-Trichloroaniline 10,3,4-Dichloroaniline 11, 3-Nitroaniline 12, 2,4,5-Trichloroaniline 13,4-Chloro-2-nitro Aniline 14, 4-nitroaniline 15, 2-chloro-4-nitroaniline 16, 2, 6-dichloro-4-nitroaniline 17, phenanthrene-d10 18, 2-bromo-6-chloro-4- Nitroaniline 19, 2-Chloro-4,6-dinitroaniline 20, 2,6-Dibromo-4-nitroaniline 21, 2,4-Dinitroaniline 22, 2-Bromo-4,6 -Dinitroaniline

3 Summary

GC-MS6800 is used to determine aniline compounds in water. The instrument has high sensitivity, good stability, and can meet the requirements of national standards.