• Hydrodesulphurisation
(HDS)
activity • Hydrodenitrogenation (HDN) activity • Aromatic saturation and volume swell • Hydrogen consumption • C 5 + yield Hydrodesulphurisation activity Figure 2 shows ULSD pilot plant testing and compares the fresh hydrodesulphurisation (HDS) activ- ity with its Excel or stacked bed configurations. We can observe the Excel rejuvenated catalyst’s enhanced behaviour as a stan- dalone or stacked bed configuration compared to its parent fresh. This results in a HDS relative volumetric activity (RVA) between 100% and 104% for all the rejuvenated config - urations compared to fresh, while achieving the 10 ppmwt product sulphur range. Hydrodenitrogenation activity Figure 3 shows ULSD pilot plant testing and compares the fresh hydrodenitrogenation (HDN) activity with its Excel or stacked bed configurations. We can observe that a full load of rejuvenated cat- alyst or combined with fresh cata- lyst in a stacked bed configuration (30% Excel NiMo and 70% fresh catalyst) exhibited an equally high activity as a full load of fresh cata- lyst. We find HDN-RVA between 100% and 105% for the 10 ppmwt product sulphur range compared to fresh. Using some Excel reju - venated CoMo catalyst (30%) at the bottom of the loading with fresh or Excel NiMo catalyst at the top, both stacked configurations show slightly lower HDN activ- ity between 90% and 94% vs fresh while reaching the 10 ppmwt prod- uct sulphur range. This is expected since NiMo has higher HDN and aromatic saturation versus CoMo in high-pressure applications, espe- cially when processing cracked feedstocks with high levels of nitrogen and aromatics. Hydrodearomatisation activity In Figure 4 , the aromatics content is represented for the feed and products specific to all the catalyst
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c(S) Fresh NiMo c(S) Excel NiMo c(S) 30% Excel NiMo / 70% Fresh NiMo c(S) 70% Fresh NiMo / 30% Excel CoMo c(S) 70% Excel NiMo / 30% Excel CoMo
Excel NiMo 70% Excel NiMo / 30% Excel CoMo 30% Excel NiMo / 70% Fresh NiMo 70% Fresh NiMo / 30% Excel CoMo
Figure 2 HDS-RVA of Excel rejuvenated configurations vs fresh NiMo catalyst activity
configurations tested at 358°C (con - dition 6), whereas aromatics for feed and products at 365°C (condi - tion 9) are represented in Figure 5 . In Figure 5 , condition 9 allows for
the highest volume swell, resulting in higher aromatic saturation than condition 6. This can be explained by the higher reactor temperature used, namely 365°C, reaching the
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c(S) Fresh NiMo c(S) Excel NiMo c(S) 30% Excel NiMo / 70% Fresh NiMo c(S) 70% Fresh NiMo / 30% Excel CoMo c(S) 70% Excel NiMo / 30% Excel CoMo
Excel NiMo 70% Excel NiMo / 30% Excel CoMo 30% Excel NiMo / 70% Fresh NiMo 70% Fresh NiMo / 30% Excel CoMo
Figure 3 HDN-RVA of Excel rejuvenated configurations vs fresh NiMo catalyst activity
PTQQ 2 2022 51
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