Suppressing Dehydroisomerization Boosts n-Butane Dehydrogenation with High Butadiene Selectivity

Area of Science:

• Chemical Engineering
• Catalysis
• Materials Science

Background:

• Butadiene (BD) is a vital industrial chemical, traditionally made from naphtha cracking.
• Limited oil reserves and rising BD demand necessitate alternative production methods, such as n-butane direct dehydrogenation (n-BDH) using shale gas.
• Current n-BDH catalysts suffer from low BD selectivity due to dehydroisomerization, hindering efficient production.

Purpose of the Study:

• To develop a strategy for enhancing BD selectivity in n-BDH.
• To suppress the dehydroisomerization side reaction, a major cause of low BD yield.
• To identify and optimize catalyst formulations for improved n-BDH performance.

Main Methods:

• Investigated the effect of alkali-earth metal addition (e.g., Mg, Ca) to Pt-Ga2O3/S10 catalysts.
• Analyzed catalyst properties including Pt dispersity and coke deposition.
• Evaluated catalyst performance in terms of n-butane conversion and BD selectivity at 625°C.

Main Results:

• Addition of alkali-earth metals significantly increased Pt dispersity on the catalyst.
• The modified catalysts showed suppressed coke deposition and reduced dehydroisomerization.
• The optimized Pt-Ga2O3/S10 catalyst with alkali-earth metals achieved 34.7% BD selectivity at 82.1% n-butane conversion.

Conclusions:

• Alkali-earth metal incorporation is an effective strategy to enhance BD selectivity in n-BDH.
• The developed catalysts outperform existing ones, offering a promising route for industrial BD production.
• This research advances catalyst design principles for heterogeneous catalysis applications.