Shanghai Hengxi provides the following solutions for the "GB50325-2020 Indoor Environmental Pollution Control Standard for Civil Building Engineering", including 16 TVOC injection testing requirements.

1. Test substance16 types of TVOC, as shown in Figure 1-1.

Figure 1-1 16 TVOCs

2. Instrument configuration

Pre processing equipment: Shanghai Hengxi ATD-801 fully automatic secondary thermal desorption analyzer

Analytical instrument: Agilent 7820A gas chromatography (FID detector)

Sampling tube: T-C composite adsorption tube

• Instrument conditions

3.1 Condition parameters of fully automatic secondary thermal desorption instrument:

• Sample tube temperature: 300 ℃
• Transmission tube temperature: 180 ℃
• Secondary tube temperature: 280 ℃
• Cold trap: -30 ℃
• Blowing time: 300s
• Analysis time: 10 seconds
• Injection time: 240 seconds
• Backblowing time: 1200s
• Blow flow rate: 50ml/min
• Backflow rate: 100ml/min

3.2 GC condition parameters：

• injection port

Temperature: 250 ℃; Diversion mode: diversion; Split ratio: 20:1; Carrier gas: N2.

• chromatographic column

Column specification: 50m * 0.320mm 0.25Micron; Column flow rate: 2.0ml/min.

Program heating: as shown in Figure 3-2-1.

Figure 3-2-1 Program Heating Parameters

• Detector FID (Hydrogen Flame)

Temperature: 250 ℃; Hydrogen flow rate: 30ml/min; Air flow rate: 300ml/min; Tail blowing: N2, 25ml/min.

• experimental results

4.1 16 TVOC chromatograms (low concentration 0.05mg/ml)

4.2 Linearity of Various Substances

The calibration data is as follows:

The linear chart is as follows:

Figure 4-1 n-hexane

Figure 4-2 Benzene

Figure 4-3 Trichloroethylene

Figure 4-4 Toluene

Figure 4-5 Octene

Figure 4-6 Butyl acetate

Figure 4-7 Ethylbenzene

Figure 4-8 p-xylene

Figure 4-9 o-xylene

Figure 4-10 Styrene

Figure 4-11 Nonane

Figure 4-12 Isooctanol

Figure 4-13 n-undecane

Figure 4-14 n-Tetradecane

Figure 4-15 n-Hexadecane