Document Type : Original research

Author

• Saeed K. Amini

Chemistry and Chemical Engineering Research Center of Iran, Tehran, Iran

Abstract

Activity of 111 surface of PtGa alloy in which three atom Pt centers are covered by In atoms is investigated as single atom Pt catalyst of propane dehydrogenation (PDH) by using quantum mechanical (QM) calculations. Periodic density functional theory (DFT) is applied in these calculations, utilizing PBE exchange-correlation functional with plane wave basis set of 680eV kinetic energy cut off. Calculated results give adsorption and conversion energies of propane to propylene including adsorption energies of intermediate states. Adsorption energies span is from -6 kJ/mole for propane up to -500 kJ/mole for CH₃CH₂CH₂ radical. Catalyzed propane to propylene’s conversion energy is about -135 kJ/mole in comparison to about 150 kJ/mole of gas phase. Moderate adsorption energy value of about -120 kJ/mole for propylene and its higher conversion energy value of about 160 kJ/mole to CH₃CH^*CH₂ intermediate guarantee propylene slectivity and break of conversion chain after its formation. Lower activation energy values of first and second C—H breaks show that PDH reaction on this prposed catalyst is much faster than previously reported one in which three atom Pt centers were covered by toxic Pb atoms.

Keywords

• PDH
• Single atom Catalyst
• PtGa/In
• QM
• plane Wave

Main Subjects

• Olefin synthesis