The detection and in particular the identification of trinitrotoluene (TNT), dinitrotoluene (DNT) and nitrotoluenes (NT), as well as derivatives thereof, particularly when investigating soils for detecting scrapped armaments in the countryside or the area around explosives enterprises is of great importance. Although frequently only areas of a few square kilometres at individual, unknown locations are contaminated with TNT pockets with a size of square meters, it has hitherto generally been necessary to completely remove the soil of the uncontaminated areas. This is in particular due to the fact that the known analysis methods are expensive and lead to considerable time expenditure. It is necessary to take samples from the area, which can then only be analysed after approximately one hour at the analytical location provided for this purpose. Thus, a precise demarcation of the contaminated area is only possible in this way with considerable time and labour costs. The known analytical apparatuses for TNT determination also require approximately one hour for testing a sample. As in addition the disposal costs rise significantly with the volume of the contaminated excavated material, either a time-consuming determination of the precise contaminated soil area is necessary, or possibly too much soil must be removed with the resulting disposal costs.
However, it is not only necessary to test soils, but also liquids with respect to contamination with TNT, DNT, NT and derivatives thereof, because waste, seepage and ground waters can become contaminated by soil containing the aforementioned substances or by the soil cleaning processes. Once again at present only relatively time-consuming expensive processes are available, such as gas chromatography.
In addition, most explosive charges are made from TNT or with the addition of TNT due to the technologically simple production and processability. As such explosives are also used in blackmail or terrorist threats and attacks, the discovery of such explosives, e.g. in luggage and passenger checks at airports and the like represents an important task in order to prevent danger to human life. However, a rapid and uncomplicated detection of mines is indispensable when searching for plastic-enveloped mines.
The TNT used in the manufacture of explosives is a solid giving off small quantities of vapour to the environment. However, this vapour can only be detected with very complicated and costly methods, such as gas chromatography with mass spectrometry.
The problem of the invention is therefore to provide a process and an apparatus for identifying such contaminations in the soil, liquids and gases, which is characterized by a simple, rapid and inexpensive detection of TNT, DNT and NT in situ and also contaminations of varying concentrations can be reliably and simply detected in the most varied substances, such as soils, liquids, etc.