Thermal Hydrogenolysis of Polyaromatic Hydrocarbons and Activated Carbon at Elevated Temperatures and Pressures

Abstract

Vaporised polyaromatic hydrocarbons (indene, naphthalene, biphenyl, phenanthrene, anthracene) admixed with benzene, have been processed in flow reactors at 1−35 bar H2 at temperatures between 500 and 990 °C. Smooth gasification to methane on a 4−20 s timescale occurs, nearing completion at the higher T and P values. Relative rates at 977 °C (benzene/naphthalene/anthracene ca. 0.1:1:2.5) are interpreted on the basis of the mechanism advanced earlier for benzene: (reversible) addition of H• and opening of target aromatic rings. Activated carbon reacts analogously, but on a per C basis its rate is about 500 times smaller than that of naphthalene. Resistance to ring‐opening hydrogenolysis in highly condensed entities and limited accessibility for H2/H• together account for this difference.

A Deep Insight into the Details of the Interisomerization and Decomposition Mechanism of o-Quinolyl and o-Isoquinolyl Radicals. Quantum Chemical Calculations and Computer Modeling

“…The production of H atoms via C–H bond cleavage is the initiation step in the thermal decomposition mechanism of aromatic ring compounds such as benzene, , naphthalene, , and many others. There are also six-member aromatic rings containing nitrogen, such as pyridine, picoline, quinoline, and isoquinoline that are also responsible for the production of hydrogen atoms. − …”