Effect of Sr Addition to Ni/Al2O3 Catalyst for Phenol Steam Reforming under Dilute Conditions

Removal of harmful phenol from exhaust gases emitted during plastic pyrolysis requires an effective catalyst for phenol steam reforming under dilute conditions. Sr addition to Ni/Al2O3 catalyst, a common steam reforming catalyst, improved the catalytic activity for hydrogen production. Ni/Sr/Al2O3 catalyst, in which Ni was loaded onto Sr/Al2O3, was more effective than Sr/Ni/Al2O3 catalyst, in which Sr was added to a Ni/Al2O3 catalyst. In addition, Ni-Sr/Al2O3 catalyst, in which Ni and Sr were co-loaded onto Al2O3, showed similar effects but was inferior to Ni/Sr/Al2O3. The optimum Sr/Ni molar ratio was 1 for the Ni/Sr/Al2O3 catalysts. The effect of Sr addition was to increase the basic adsorption sites of phenol and to modify the electronic state of the reaction site due to the electron donation effect from Sr to Ni. The combination of these two factors improved the catalytic activity.