Use of 2,4-dinitrophenylhydrazine for the purification of technical isoprene from carbonyl compounds

Abstract

Summaryo1.Technical isoprene can be freed from carbonyl compounds by conversion into non-volatile derivatives—hydrazones, with subsequent liberation of the purified isoprene during re-evaporation. The reaction takes place at room temperature with a molar ratio of 2,4-dinitrophenylhydrazine/carbonyl compounds in the range 2–10 to 1.2.This method of purification may also be used in other situations where a hydrocarbon flow freed from aldehydes and ketones is required. Technical isoprene can be freed from carbonyl compounds by conversion into non-volatile derivatives—hydrazones, with subsequent liberation of the purified isoprene during re-evaporation. The reaction takes place at room temperature with a molar ratio of 2,4-dinitrophenylhydrazine/carbonyl compounds in the range 2–10 to 1. This method of purification may also be used in other situations where a hydrocarbon flow freed from aldehydes and ketones is required.