Abstract
Porous Al2O3 and Al2O3/TiO2 particles, about 1mm in diameter, were prepared from Al(OH)3/alginate gel composite precursors. In this process, urease was immobilized in Al-bridged alginate gel matrices and then urea was allowed to diffuse into the matrices. The bridging Al3+ ions were then hydrolyzed by the enzymatically produced ammonia to form Al(OH)3 within the pores of the alginate gel. Both hollow and solid particles were able to be prepared by controlling the synthesis procedure. The specific surface area of calcined particles was in the range about 100m2/g, depending on the calcination temperature. The pore size distribution was quite narrow, and the distribution profile was also controllable. Photocatalytic activity was characterized for TiO2-modified particles.
