Characterization of nitrogen on aged hydroprocessing catalysts by temperature-programmed oxidation

Investigation of carbonaceous compounds deposited on NiMo catalyst used for ultra-deep hydrodesulfurization of gas oil by means of temperature-programmed oxidation and Raman spectroscopy

“…During TPO of the spent NiMo-A catalysts, H 2 O, CO x , SO 2 and small amount of CH 3 CN [10] were detected during TPO-MS. NO x was not detected at all although several authors reported that NO x is detected during TPO of the catalysts that had been used for the heavy oil processing [5,8,12]. Fig.…”

“…Thus, this technique has a potential for providing quantitative insight into the impact of the carbonaceous compounds upon the catalyst deactivation. So far, several authors have reported TPO-MS profiles of the carbonaceous compounds deposited on NiMo catalysts used for the HDS of straight run gas oil (SRGO) [5], vacuum gas oil (VGO) [6,7,8] and heavy petroleum fraction [9]. However, the carbonaceous compounds on the NiMo catalyst used for the ultra-deep HDS of gas oil have never been investigated by TPO techniques yet.…”

Effect of phosphorus on activity of hydrotreating catalyst of Maya heavy crude

“…Studies also show that P increases the dispersion and reducibility of Co and Mo species [8][9][10]. Phosphorus increases the size of the MoS 2 slab as well as the stacking number [11], but others have reported a decrease in the MoS 2 length with the addition of phosphorus [12].…”

Nitrogen Chemistry and NOx Control in a Fluid Catalytic Cracking Regenerator

“…There exists extensive literature on the nitrogen chemistry during coal combustion (Bassilakis et al, 1993;Wojtowicz et al, 1993). Systematic work was also reported for the formation of nitrogen compounds during the regeneration of spent hydroprocessing catalysts (Zeuthen et al, 1991;Furimsky et al, 1995Furimsky et al, , 1996. Figure 4 is a schematic showing of the transformation of coal-bound nitrogen during coal combustion (Wojtowicz et al, 1993).…”