1.000 1.025 1.050 1.075 1.100 1.125 1.175 1.150 1.200
MoS structures
S1
S2
S2
S1
High dispersion
Low dispersion
2.50
2.55
2.60
2.65
2.70
2.75
Avg. slab length (nm)
S1
S2
Figure 3 Edge and element dispersion in CoMo BRIM (S1) and trimetallic TK-594 HyBRIM (S2)
US West Coast and a Russian blend of heavy gasoil (see Table 1 ). The pilot test illustrates the catalyst’s performance while targeting medium to high sulphur conversion at two different levels of feed nitrogen and sulphur but at similar operating conditions. The test of TK-594 HyBRIM was conducted in a side-by- side reactor set-up, along with two top-tier NiMo catalysts: TK-569 HyBRIM and TK-611 HyBRIM. Figure 4 shows that TK-594 HyBRIM displays superior HDS activity and compa- rable HDN performance when compared to the other two pure NiMo catalysts systems. This is despite the high nitro- gen content of the US West Coast feedstock. This advantage displayed by TK-594 HyBRIM is an important consider- ation for hydrotreating units where the catalyst’s stability
and volume swell over the entire cycle length are the main objectives. When testing the Russian blend heavy gasoil, TK-594 HyBRIM also shows superior HDS performance compared to the other two NiMo catalysts systems. TK-611 HyBRIM shows a better HDN performance than TK-594 HyBRIM at these conditions, which is expected due to the lower nitro- gen in the feed. However, TK-594 HyBRIM shows slightly higher activ- ity than TK-569 HyBRIM. The high HDS activity is a result of the extra direct desulphurisation (DDS) performance of TK-594 HyBRIM at these conditions when compared to any pure NiMo catalyst system. Comparative stabilities Figure 5 shows the deactivation rate in the pilot test unit of three catalyst systems that were exposed to the same operation conditions using the same feedstock. The
US West C oast heavy gasoil
Russian blend heavy gasoil
TK-611 HyBRIM TK-569 HyBRIM TK-594 HyBRIM
NiMo shows la r ger deactivation than CoMo/TK-594 HyBRIM catalysts
Stacked NiMo/CoMo & TK-594 HyBRIM catalysts show comparable deactivation 1400 1000 600 1200 800
200
1600
0
400
Run hours on-stream
NiMo catalysts
TK-594 HyBRIM Stacked NiMo/CoMo
HDS
HDN
HDS
HDN
Figure 4 Side-by-side HDS/HDN comparison between tri- metallic TK-594 HyBRIM vs TK-611 HyBRIM and TK-569 HyBRIM
Figure 5 Side-by-side pilot scale deactivation rate compar- ison between trimetallic TK-594 HyBRIM, 100% NiMo, and stacked CoMo catalyst load
53
PTQ Q4 2024
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