This study investigates the mechanism of aromatic formation from acetylene over zeolite catalyst. The mechanism of reaction was focused following continuous acetylene addition scheme at two different phases: gaseous and adsorbed phase. By evaluating the Gibbs free energy (ΔG) profile of theoretical density functional theory (DFT) calculation, the comparison could summarize adequately if in the presence of zeolite particle, the aromatic formation reactions could have reduced barrier energies of addition reactions with respect to the gaseous phase ones, a sort of catalytic effect. The mechanism of phenyl formation via radical reaction is showed in Figure 1.

Figure 1. The mechanism of phenyl formation via radical reaction