Sensible diesel hydrotreating catalyst selection: An independent catalyst testing approach

Due to transition from Euro IV to Euro V fuel specifications in multiple regions, refiners around the world have faced more challenges in meeting the targeted catalyst cycle length while processing opportunistic feedstocks, e.g., heavy-sour crudes.

Over the past two years, Avantium has led multiple commercial diesel hydrotreating catalyst benchmarking programs, and this practice has increasingly gained traction. Read the full article to explore how the right catalyst can transform diesel hydrotreating processes and drive profitability.

Key Highlights:

• A paradox of catalyst selection: Discover how diesel hydrotreating catalyst selection can be surprisingly more difficult than other refining applications.
• Independent Testing: See how it can be leveraged to prove the new operating strategy of the diesel hydrotreating unit.
• Handle dirty feedstocks: Learn about a general catalyst loading strategy to handle dirty feedstock like LCO.
• Trade-off between catalyst activity and liquid product yield: Learn about a topic that is rarely discussed in diesel hydrotreating.
• Pilot plant testing: Understand how to realistically scale down a large-scale diesel hydrotreating process and design a representative independent catalyst testing program.

Challenges in diesel hydrotreating catalyst selection

Key Highlights:

• Diesel hydrotreating net conversion is typically less than 5.0 wt% without dewaxing, making it difficult to distinguish the best catalyst based on yield gaps alone.
• Hydrogen consumption is considerably lower than that of hydrocracking, making the assessment more challenging because the differences between vendors can be minimal.
• Predicting product properties with different estimators makes direct comparisons less useful, particularly in terms of volume swell.
• Catalyst activity is estimated using kinetic models, but each vendor has their own models and assumptions, leading to comparison biases.