Identification and reactivity of nitrogen molecular species in gas oils

Nitrogen molecular species in several gas oils were analyzed by gas chromat ograph with an atomic emission detector (GC-AED) and mass spectrometer (GC- MS). Nitrogen species in gas oils were divided through acidic extraction in to basic species (such as aniline, quinoline, benzoquinoline, and their der ivatives) and nonbasic species (such as indole, carbazole, and their deriva tives). To be mostly identified, their distribution depended on the cutting point and origins of gas oils. Denitrogenation reactivities of nitrogen sp ecies in gas oils were followed in the hydrotreating reactions at 340 degre es C under 5MPa of H-2 to quantify by GC-AED their respective reactivities in GOs, The reactivities orders and reactivity dependence on their chemical structures and matrix compositions are discussed on molecular bases. The r eactivity order was found as indole > methylated aniline > methylated indol e > quinoline > benzoquinoline > methylated benzoquinoline > carbazole > me thylated carbazoles. The number and position of methyl groups were very inf luential on the reactivities of carbazole derivatives. Methyl groups neighb oring the N atom inhibited remarkably the HDN reactions. Comparison of the reactivities of the same species in the GOs must be discussed by taking acc ount of all components and products in the respective oil.