Pentachlorobenzene

• Penta chlorobenzene
• Quinto chlorobenzene
• QCB

Colorless, flammable solids

Fixed

1.834 g · cm -3

82-85 ° C

275-277 ° C

16 Pa ( 100 ° C)

Practically insoluble in water

Risk

1080 mg · kg -1 ( LD50, rat, oral)

Template: Infobox chemical / molecular formula search available

Pentachlorobenzene is a chemical compound selected from the group consisting of aromatic chlorinated hydrocarbons.

Production and representation

Pentachlorobenzene is recovered as a by-product in the production of tetra- chlorobenzenes, and can be extracted by a subsequent distillation, and crystallization. The direct preparation of pure pentachlorobenzene is practically impossible due to the parallel formation of different degrees of chlorinated compounds. Since it is also generally produced in small quantities in the chlorination of benzene, it is also in chlorobenzene ( tetrachlorobenzenes, hexachlorobenzene, ...) included.

Use

Pentachlorophenol, benzene was used as an intermediate for the production of the crop protection and disinfectant pentachloronitrobenzene ( quintozene ). Since this compound is banned in Germany since 1992 (since 2002 in the EU), the production of pentachlorophenol, benzene was adjusted. Nevertheless, in 2006 Pentachlorobenzene in low concentrations in German waters was (for example the Rhine ) detected.

Safety

Pentachlorobenzene is one of the persistent organic pollutants (only anaerobic degradation ), whereby an accumulation in the food chain is possible (see also Stockholm Convention ). It is very toxic to aquatic organisms, flammable and decomposes on heating or on burning producing toxic, corrosive fumes ( hydrogen chloride, phosgene). Thermal decomposition may result in the presence of oxygen Polychlordibenzo -p -dioxins and polychlorinated dibenzofurans.

Proof

Pentachlorobenzene can be demonstrated by solid-phase extraction followed by GC / ECD analysis up to a limit of 0.025 ug / l.