Chromatographic determination of aromatic hydrocarbons in ambient air

A gas chromatographic method has been developed for the determination of aromatic hydrocarbons in solvent mixtures. Bulk solvents and charcoal tube air samples may be analyzed. The procedure utilizes the unique separation characteristics of a gas chromatographic column containing a highly selective stationary liquid phase, N,N-bis (2-cyanoethyl) formamide. The interfering oxygenated solvents are extracted using 75 percent H2SO4. An 11-foot, 35 percent CEF column may be used to qualitatively analyze the lower boiling aromatic hydrocarbons (benzene, toluene, xylenes). Total or specific aromatics are then quantitated using a 3-foot, 35 percent CEF column with an internal standard. Applications of liquid chromatographic concepts to this analysis were also investigated.