VAPOR-PHASE OXIDATION OF BENZOIC-ACID TO PHENOL OVER NA2O-PROMOTED NIO-FE2O3 CATALYST

A NiO-Fe2O3-Na2O catalyst achieved an extremely high space-time yield (STY) of phenol, while maintaining a high phenol selectivity, as compa red with that of a conventional CuO catalyst for the vapor phase oxida tion of benzoic acid. The addition of Na2O to NiO-Fe2O3 catalyst was f ound to be very effective in increasing the STY of phenol, while maint aining a high phenol selectivity. The effect of temperature, oxygen ra tio, H2O ratio, and space velocity on the catalyst performance were ex amined in order to optimize the phenol selectivity and STY of phenol. The reaction route for phenol formation over the Na2O-promoted NiO-Fe2 O3 catalyst was also speculated upon by considering the deactivation o f the catalyst.