Pyrrole and its homologues are mainly present in bone tar, and the amount of coal tar present is small. Pyrrole can be obtained by bone tar fractionation; or treated with dilute alkali, and then acidified after fractionation purification. It is a five-membered heterocyclic compound containing a nitrogen heteroatom and its formula is C4H5N.
1, furan and ammonia as raw materials, γ-alumina as a catalyst, the gas phase catalytic reaction derived.
2, by the bone oil and sulfuric acid pyrolysis, so that into its potassium salt (C4H4NK), washed with ether and water treatment and then dry, fractional derived. From galactose diacid ammonium in glycerol or mineral oil pyrolysis.
Purification method: Pyrrole is distilled in a nitrogen stream. Or in the nickel cyanide nickel solution made of pure complex, and then dry distillation.