Preparation of spherical alumina and copper oxide coated alumina sorbents by improved sol-gel granulation process

Granular alumina (Al₂O₃) and copper coated Al₂O₃ sorbents were prepared by a continuous sol-gel process that could be the basis of a large-scale plant for production of the new sorbents by the sol-gel method. This continuous fabrication process allows the production of the sorbents in a larger quantity as well as in a more consistent shape and size. In addition, several improvements were done to the current synthesis procedure for sol-gel-derived pure γ-Al₂O₃ and copper doped Al₂O₃ granules, which include the preparation of the sorbents using alternate cost-effective raw materials, the elimination of the washing step and the fast drying of the beads by a microwave technique. These improvements simplify the sorbent synthesis process, minimize the wastes generated, reduce the preparation time, and decrease the production cost. The pore structure, mechanical strength and attrition rate of the sorbents prepared in this work were studied and compared with the properties of the best sorbents commercially available. Excellent pore structure and superior crushing strength were found in the sorbents prepared in this work compared to their commercial counterparts.