Understanding catalytic hydrotreating of hydrothermal liquefaction nitrogen-rich biocrude in a two-stage continuous hydrotreater

• DOI: 10.1016/j.cej.2023.148333
• Publication Date: 2023-12-25T15:41:39Z
• Authors: Daniele Castello; Muhammad Salman H...; Stefano Chiaberge; Lasse Aistrup Ros...
• Keywords: Hydrothermal liquefaction; Hydrodeoxygenation; Naphtha

Hydrothermal liquefaction biocrude from non-lignocellulosic feedstocks often shows properties, such as a high presence of inorganics, oxygen and especially nitrogen content, which are challenging in view hydroprocessing for the production drop-in biofuels. In particular, removal requires severe conditions, that might compromise continuous operations affect yield different hydrocarbon fractions. This work demonstrates possibility successful long-time microalgae biocrude, feed with content metals nitrogen, thanks to multi-stage approach sulfided catalysts. Whereas hydrodeoxygenation was achieved at relatively mild challenging. By using number advanced characterization techniques, among FTICR-MS, it possible unveil how takes place reaction severities, terms temperature, WHSV pressure. High needs temperature (∼400 °C) low space velocities is associated H2 consumption. causes also remarkable change boiling point distribution, shifted products gasoline range, while yields middle distillates marginally affected by hydrotreating severity. seems be consequence denitrogenation mechanism, promoting fragmentation larger molecules heavy fractions biocrude.