Influence of nitrogen compounds on hydrodesulfruization lf thiophene

Influence of nitrogen compounds on hydrodesulfurization of thiophene was investigated in this study. Catalyst used in this study was CoMo/A1₂O₃. The experiments were conducted in a fixed bed reactor at a temperature of 210℃ and a pressure of 2.73 MPa. Equimolar (equivalent to 0.5 wt% N as nitrogen compounds) concentration of each nitrogen compound was added to make the feedstock. Substances used to represent nitrogen compounds were pyridine, quinolone, 1,2,3,4-tetrahydroquinoline, 2,6-1utidine and pyrrole. The results showed that the addition of various nitrogen compounds even at low concentration to the feedstock inhibited thiophene conversion. The inhibition effect is expected to be the competitive adsorption of nitrogen compounds on the active sites. Inhibition strength depended upon type and structure on the active sites. Inhibition strength depended upon type and structure of nitrogen compounds. Basic nitrogen compounds inhibited more than non-basic nitrogen compounds. The inhibition decreased with the saturated ring of nitrogen compound. Nitrogen compound which had stearic hindrance in structure decreased the inhibition and increased the coke formation. Adsorption of nitrogen compound is founded to be through nitrogen atom rather than -bonding of ring.