PARTICULARITY ON LIQUID CHROMATOGRAPHIC SEPARATION FOR AN EQUIMOLAR MIXTURE OF 2,4-DINITROPHENYLHYDRAZONES PROVIDED BY ACETALDEHYDE AND DIACETYL

Abstract

An equimolar mixture of 2,4-dinitrophenylhidrazones (2,4-DNPH-ones) providing by acetaldehyde and diacetyl has been analyzed by liquid-chromatographic separation, using the mechanism of partition with reverse phase. As mobile phase are utilized various binary mixtures, containing water (0 – 45%) and methanol. By the experimental studies were identified four domains of behavior and two optimal binary mixtures, containing 25 and 45% water respectively. The peaks are characterized by values of retention time and by position. The separation processes were appreciated by difference between the retention times of peaks; if the percent of water increase, the values of retention times is higher, heaving a maxim value when the percent of water is 25%. For a mixture of mobile phase with 35% water and 65% methanol, the difference between retention time’s values became null; the behavior is comparable with those of pure methanol, but for higher values of retention times. When the percent of water is 45%, the difference between the retention times is also maxim, associated with a change of peaks positions.

Keywords

• 2
• 4-dinitrophenylhidrazones
• acetaldehyde
• diacetyl
• inversion
• reverses phase
• polarity
• percent of water