Comment:
0.3 - 3 wt% B/Al2O3. The samples were prepared by pore vilume impregnation of gamma - alumina with solution containing various amounts of boric acid. The samples were dried at 403 K for 4 h between impregnaton steps, and finally dried at 403 K for 16 h then calcined in air at 873 K for 6 h.