Development and Intensification of the Ethylene Process Utilizing a Catalytic Membrane Reactor

Area of Science:

• Chemical Engineering
• Petrochemical Processes
• Catalysis

Background:

• Ethylene is a crucial petrochemical, primarily produced by expensive thermal cracking.
• Ethane dehydrogenation (EDH) is limited by endothermic reactions and thermodynamic equilibrium.
• Developing efficient ethylene production methods is vital for the petrochemical industry.

Purpose of the Study:

• To investigate the use of a catalytic membrane reactor (MR) for enhanced ethylene production via EDH.
• To analyze the impact of operating conditions and reactor configurations on EDH conversion.
• To develop and evaluate new, economically viable ethylene production processes.

Main Methods:

• Utilized a catalytic membrane reactor with a palladium-silver (Pd-Ag) membrane to remove hydrogen and shift equilibrium.
• Investigated the effects of temperature, pressure, and reactor design on ethane conversion.
• Developed two novel process configurations for industrial-scale ethylene production.

Main Results:

• Achieved 22.2% ethane conversion in the MR at 660 K and 300 kPa without auxiliary reactions.
• Increased ethane conversion to approximately 99% by incorporating benzene hydrogenation as a simultaneous reaction.
• Developed processes for 100,000 metric tons/year capacity, one requiring cryogenic distillation and another producing cyclohexane as a byproduct.

Conclusions:

• Catalytic membrane reactors significantly enhance ethylene production from EDH by overcoming equilibrium limitations.
• The process integrating benzene hydrogenation offers a highly efficient and potentially more economical route, avoiding cryogenic separation.
• The cyclohexane-producing process demonstrates strong economic viability with a 34.4% return on investment, marking it as a promising technology.