In recent years, with the increase in peoples environmental awareness, automobile environmental protection has gradually attracted consumer attention. The air in the vehicle, disable material testing and other work have become an important part of the production of vehicle production.
According to an expert, the source of air in the car is everywhere: the items such as the console, the chair, the roof felt, the soles of the foot, and the spare parts and the glue themselves are all The harmful gases are constantly released at a moment. A large amount of formaldehyde, benzene, and other substances that are harmful to the human body are full of the car. Therefore, air detection in the car is particularly important.
VOC is a volatile organic matter, with a variety of definitions. The World Health Organization is defined as an organic compound with a melting point below room temperature (20 deg; C) and the boiling point at 50-260 deg; C. TVOC (C6-C16) refers to all reserved time in C6 The general term of the organic compounds of peaks between the retention time of C16.
1. The standard of the VOC of the vehicle
At present, there are only two direct standards for automobile VOCs issued by my country, namely HJ/T 400 Method of Sample Sample Sample Material Sample Sample Sample Sample Material Samples in the Car and IOS 27630 Inside Passenger Cars Air Quality Evaluation Guide . Taking the national standard 27630 as an example, the standard requirements are as follows:
Since ISO standards and WP29 GTR only formulate test methods, there is no setting limit, so the relatively comparable standards are only South Korean national standards and standards and standards for national standards and standards and standards for national standards and standards. Japans Jamas autonomous action plan, Table 6-8 shows the standard limit of the standard limit of China, Japan and South Korea.
In different experimental modes, VOC experiment results comparison
The figure below shows the experimental results of experimental vehicles at high temperature, room temperature (25 deg; C) and driving mode.
Experimental vehicle first performs 16 h at the HJ/T400-2007 standard, and then exposes 4 h in the sun (the temperature in the car is close to 60 deg; C, higher than ISO and Jama than ISO and Jama The prescribed ambient temperature) simulates the high -temperature parking mode under the summer sun, and the air samples in the car of 30 min after a high temperature closed for 4 h.
After the sampling of the high -temperature parking mode is completed, enter the driving mode. The driver opens the door of the side door of the cab. After entering the car, quickly close the door (the door opens to the closing time is less than 1min), and then start the engine and maintain idle operation. Turn on the air conditioner in the car, set the temperature minimum, set the circulating air volume to the maximum, and finally perform the air sample of 30 min in the car.
The experimental results in the three modes are shown in FIG. Among them, in the high temperature parking mode, the concentration of various control substances measured in the car is 1.5- About 2.5 times. The concentration of various substances in the driving mode is the lowest, and the minimum value is only about 10-20%of the normal temperature mode.
2. The detection method of material and parts VOC
1. Bag method
The main application In the Japanese car factory, the test parts are placed in a sealed sample bag, and a certain amount of high -purity nitrogen is connected to the sample bag. After heating, the VOC of the test parts volatilizes it into the bag. In the adsorption pipe, the hydrocarbon is captured by Tenax, the aldosone is caught by DNPH, and finally analyzes its volatilization with ATD-GC/MS and HPLC.
2. Thermal analysis method
This method is mainly used in Europe and the United States. The sample solving the hot removal of 90 deg; C in the straw for 30 minutes. In the GC analysis, the semi -quantitative analysis of all color spectrum peaks within the C20 according to the standard curve of toluene is obtained from the total VOC value or a single material quantity.
Put the absorbing tube that has been analyzed through VOC analysis on ATD 120 deg; C 60 minutes and re -attach it again. The semi -quantitative analysis of all color spectrum peaks between the peak time between the peak time from C16 and C32 obtains the total atomization volatilization.
3. Total carbon volatilization test -top empty method
Top empty method is a common method for European and American car companies. Heat the sample to 120 deg; C; the substance volatilized by the sample to GCMS; comparison between the sample peak area and the air peak areaAs an assessment of sample volatilization; what substances volatilizes the samples through mass spectrometry; evaluate the risk of these volatile substances on people.
4. Formaldehyde test
The main sources of formaldehyde in the car are materials such as dermis, electroplating, paint, and plastic decoration. Especially for high -end cars, in order to ensure their comfort and use insulation and cold -proof materials and sound insulation materials, these materials use volatilization such as formaldehyde during the manufacturing process.
The current method of detecting formaldehyde is:
(1) Lighting optical method:
The reaction of formaldehyde gas in the air and phenolu reagent to generate azine, azinezine, azine, In an acidic solution, it is oxidized by high -priced iron ions to form a blue -green compound, and it is quantitative than color according to the shade of the color according to the shade of the color.
(2) The optical lighting method:
Formaldehyde gas is absorbed by water after pH 6, acetic acetone in acetate, and acetone. Under the condition of boiling water bath, a stable yellow compound is quickly generated, which is determined at 413nm in the wavelength.
(3) Qi phase chromatography and liquid chromatography method:
At present, the on -site detection of formaldehyde is used to use portable formaldehyde measurement instruments, which uses solution to absorb sampling. Electric potential electrolysis method.