Simulation of Organic Liquid Product Deoxygenation through Multistage Countercurrent Absorber/Stripping Using CO₂ as...

Area of Science:

• Chemical Engineering
• Process Simulation
• Renewable Energy

Background:

• Palm oil thermal catalytic cracking produces organic liquid products (OLP).
• Deoxygenation is crucial for upgrading OLP into valuable fuels and chemicals.
• Supercritical carbon dioxide (SC-CO2) offers a promising, environmentally friendly solvent for separation processes.

Purpose of the Study:

• To systematically investigate the deoxygenation of OLP using SC-CO2 in a multistage countercurrent absorber system.
• To design and simulate an improved flowsheet for enhanced deacidification of OLP.
• To evaluate the efficiency of SC-CO2 in separating hydrocarbons and oxygenated compounds from OLP.

Main Methods:

• Process simulation using Aspen-HYSYS software.
• Modeling of thermodynamic data and equations of state (EOS) for OLP deoxygenation.
• Design of a novel flowsheet comprising absorber columns, flash drums, and heat exchangers.

Main Results:

• A recovery rate of 81.49% for OLP was achieved.
• Extracts from absorber columns contained high concentrations of hydrocarbons (96.95% and 92.78%).
• The optimal deacidification condition was identified as 333 K, 140 bar, and a solvent-to-feed ratio (S/F) of 17.

Conclusions:

• SC-CO2 is effective for deacidifying OLP, yielding fractions with reduced olefin content.
• The developed process design successfully separates and enriches hydrocarbon fractions.
• The study confirms the viability of SC-CO2 as a solvent for upgrading OLP from palm oil pyrolysis.