The four-lump kinetic model can accurately predict the N concentrations within a wide range of operating conditions (280-380[degrees]C, 4-7 MPa, LHSV
0.5-2.5 [h.sup.-1], hydrogen/oil 600 L/L).
Experiments were performed by varying the reactor temperature from 350-390[degrees]C at three LHSV ratios (ratio of Stage I to Stage II) of 1.5:1, 1:1 and 1:1.5 [h.sup.-1].
In two-stage process, temperature was varied from 340 to 390[degrees]C when pressure and LHSV were maintained constant at the optimum values of 11.0 MPa and 0.6 [h.sup.-1], respectively.
Figure 2 illustrates the relative gain in HDA rate constants at different LHSV ratios (Stage I:Stage II) in the two-stage process compared to the single-stage process.
Impact of [H.sub.2]S removal and LHSV ratio on cetane index
Figure 3 shows the impact of the [H.sub.2]S removal on the overall cetane index improvement in the two-stage process at different reaction temperatures and LHSV ratios.
HDS activity at LHSV ratios of 1:1 and 1.5:1 were similar with the former exhibiting a higher activity only at the lower temperatures (350 - 365[degrees]C).
Optimum conditions (380 [degrees]C, 6 MPa, 1 h-1 LHSV and hydrogen/feedstock of 600 (v/v)) for catalytic hydrotreating over two catalysts were chosen basing on the results above.
Experiments were conducted to compare HDS degrees of shale oil distillate over Ni-W and Co-Mo catalysts at different temperatures, pressures, LHSVs and hydrogen/feedstock ratios.
a Reaction conditions: 10 wt% glycerol aqueous solution; H 2 pressure: 6 MPa; catalyst weight: 4 g; reaction temperature: 513 K; LHSV: 0.9 h -1 b1,2-PD = 1,2-propanediol; 1-PO = 1-propanol; EG = ethylene glycol; EtOH = ethanol; MeOH = methanol
aReaction conditions: 20Cu/g-Al2O3, 10 wt% glycerol aqueous solution; H2 pressure: 6 MPa; catalyst weight: 4 g; LHSV: 0.9 h-1 b 1,2-PD = 1,2-propanediol; 1-PO = 1-propanol; EG = ethylene glycol; EtOH=ethanol; MeOH = methanol
The optimum performance over 20Cu/g-Al2O3 was observed at 513K, 6MPa H2 and LHSV of 0.9 h-1 in 10 wt% glycerol aqueous solutions.