||Self-organized formation of spherical porous granules only by one-step heat-treatment in MgO–Fe2O3–Nb2O5 system
Suzuki, Yoshikazu ,
Tokoro, HirokoAbe, Hiroya
46 , 2016-01 , Elsevier B.V.
In this letter, a new process to obtain spherical porous granules (SPGs) is presented, namely self-organized formation only by a one-step heat-treatment. Commercial MgCO3 (basic), α-Fe2O3 and Nb2O5 powders of Mg:Fe:Nb=1:1:1 in mole fraction were wet-ball milled, and were heat-treated in air at 800–1350 °C. The samples heated at ≥1100 °C, most of the samples became SPGs with the diameter of ∼50–100 μm, containing 3-D network structure. The main constituent phase of porous spheres was pseudobrookite-type MgFeNbO5. The formation mechanism of porous microspheres was discussed by using SEM observation and high-temperature XRD analysis.