Development of new alumina precipitation routes for catalysis applications

International audience-Alumina is a widely used porous material for catalytic application. Possible routes for alumina improvement can be the use of alternative precursors as well as innovative precipitation technologies. In this study, we compare the influence of both precursor chemistry and mixing efficiency on γ-alumina properties. The conventionally used boehmite and the NH4-dawsonite precursors were precipitated using three mixing technologies: a conventional stirred-tank reactor, a rotor-stator mixer and a sliding surface mixing device. It was observed that, in the study conditions, -alumina mean pore diameter and porous volume were particularly sensitive to both precursor and mixing technology, while specific surface area was rather precursor dependent. A wide porosity range can thus be covered at isospecific surface area, using several precursor/mixing technology systems