Zirconia-based porous body and method for producing same

A method for producing a zirconia-based porous body, the method sequentially comprising the following steps:

• (1) separately heating a zirconium salt solution and a solution of sulfatizing agent to 95° C. or higher;
• (2) contacting and mixing the zirconium salt solution after heating and the solution of sulfatizing agent after heating to obtain a basic zirconium sulfate-containing reaction liquid as a liquid mixture, wherein, from initiation to completion of the mixing, the weight ratio of SO42−/ZrO2 in the liquid mixture is maintained within a range of 0.3 to 0.8, and the temperature of the liquid mixture is maintained at 95° C. or higher;
• (3) aging the basic zirconium sulfate-containing reaction liquid obtained by completing the mixing in step 2, the aging being performed at 95° C. or higher for 3 hours or more;
• (4) adding an alkali to the basic zirconium sulfate-containing reaction liquid obtained after aging in step 3 to obtain a zirconium-containing hydroxide;
• and
• (5) subjecting the zirconium-containing hydroxide obtained in step 4 to heat treatment to obtain a zirconia-based porous body,
• wherein the zirconia-based porous body in the form of particles,
• (i) the zirconia-based porous body having a pore diameter peak at 20 to 100 nm in the pore diameter distribution by BJH method, a P/W ratio of 0.05 or more wherein W represents half width of the peak and P represents height of the peak in the measured pore distribution curve, and a total pore volume of 0.5 cm3/g or more;
• and
• (ii) the zirconia-based porous body having a pore diameter peak at 20 to 100 nm, the P/W ratio of 0.03 or more, a specific surface area of at least 40 m2/g, and a total pore volume of 0.3 cm3/g or more, after heat treatment at 1000° C. for 12 hours.