Comparison of different columns in analysis of C1–C5 aliphatic acids mixture in ion exclusion chromatography and vacancy ion exclusion chromatography modes

Ion exclusion chromatography (IEC) is a chromatographic technique based on the exclusion of dissociated sample molecules. This method has many applications in various analytical separations of weak acids. An alternative technique is the vacancy IEC (v-IEC), where the column is equilibrated with the sample solution flowing as mobile phase through the system, whereas pure water is injected as a sample. In this case, characteristic negative “vacant” peaks are obtained. The aim of this paper is to compare the efficiency of four RP-HPLC columns in the separation of C1–C5 aliphatic acids mixture by use of classical HPLC and very high pressure liquid chromatography. The investigations were conducted in IEC and v-IEC modes.