Sulfur Compounds
Sulfur compounds, even in structures without rings, are more complex higher in
molecular weight and may contain more than one sulfur atom:
7-Ethyl-2-(4-ethylheptyl)-3-propyldodecanethiol
2-(4-Ethyl-5-methylhexyl)-3,5-dimethyl-8-(3-methylpentylthio)nonanethiol
Similarly, structures containing rings are also larger, more complex, and higher
in molecular weight:
7-(2,3-Dimethylpentyl)-2-isobutyl-1-methyl-9-thiafluorene
Analytical Characterization
As described in the section on distillate hydrotreating, comprehensive GC has
become a very valuable tool in the characterization of the composition of vacuum
gas oils. A comprehensive GC 3D image of the hydrocarbon composition of a VGO
Table 5 FCC gasoline desulfurization process conditions
LHSV,
h
À1
Pressure, psig
(barg)
Temperature,
F (
C)
H 2 /oil, SCF/B
(Nm
3
/m
3
)
DIOS/
SHU
™
3–12
200–400 (14–28) 200–400 (90–200)
50–1,000 (8–170)
Selective
HDS, first
stage
1–3
200–400 (14–28) 475–600 (250–315) 1,500–4,500 (250–760)
Selective
HDS, second
stage
1–3
200–400 (14–28) 475–600 (250–315) 1,500–4,500 (250–315)
406
P. Kokayeff et al.