PURPOSE: To obtain the titled compound useful as a raw material for soil fungicide for agriculture with a reduced amount of impurity, by purifying pentachloronitrobenzene containing hexachlorobenzene as the impurity by vacuum distillation at a specific temperature.
CONSTITUTION: Industrically obtainable pentachloronitrobenzene (PCNB for short) containing hexachlorobenzene (HCB for short) as an impurity is distilled at 150W250°C under pressure at 3W70mmHg, preferably 5W50mmHg under a temperature condition wherein temperature at the top of a column is 150W240°C, preferably 160W220°C and temperature at the bottom of column is 160W250°C, preferably 170W230°C to give high-purity PCNB usually having ≤0.3wt% HCB content. The reflux ratio in the distillation is preferably 5W50 and the under of theoretical plate of vacuum distillation device is about 5W30.
EFFECT: The distillation can be carried out by a simple operation in a large scale and is industrially and economically advantageous.
ASANO TAMOTSU
KADANI SHINICHI
ITO HIROYUKI
