Comparative study of packed and capillary column chromatography for the characterization of vacuum gas oils

Gas chromatographic methods are of widespread use in the petroleum industry for assessing petroleum and derivatives quality. The feedstocks for catcra cking processes are very sensitive to the n-paraffin contents, which can be accurately determined using capillary column chromatography. Nevertheless, packed column chromatography does have potential advantages, viz. sometime s shorter analysis times, lower costs, higher column capacity, for vacuum g as oil analysis. This paper presents a method for such a determination usin g a Dexsil-300 packed column. The results obtained (n-alkane contents, carb on number distribution) agree fairly well with those obtained on a 30 m x 0 .25 mm DB-1 fused silica capillary column.