Porous alumina and catalyst

Porous alumina including silica (SiO2) and barium oxide (BaO) added to aluminum oxide (Al2O3), wherein

• a ratio of SiO2 addition amount to a total mass of the aluminum oxide and the SiO2 addition amount is defined as SiO2 addition ratio (mass %),
• a ratio of BaO addition amount to a total mass of the aluminum oxide and the SiO2 addition amount is defined as BaO addition ratio (mass %),
• the SiO2 addition amount is an amount obtained by converting a content of silicon (Si) in the porous alumina into a content of SiO2,
• the BaO addition amount is an amount obtained by converting a content of barium (Ba) in the porous alumina into a content of BaO,
• the SiO2 addition ratio is within a range of 3 mass % or less and the BaO addition ratio is within a range of 14 mass % or less, and
• the silica and the barium oxide are respectively added to the aluminum oxide so that a specific surface area of the porous alumina measured by a predetermined measuring method after heat treatment at 1200° C. for 30 hours is equal to or larger than a reference specific surface area of reference porous alumina for comparison in which the SiO2 addition ratio is set to 3 mass % and the BaO addition ratio is set to 0 mass % with respect to the porous alumina.