The quality of Al2O3-TiO2 mixed oxides produced in continuous mode by using two original rapid mixers (impinging jets and sliding surface mixing devices) as precipitation reactors are compared with those obtained by a standard stirred tank. The properties of agglomerate particles strongly depend on the operating conditions and particularly on the type of precipitator used for their production. (C) 2008 Elsevier B.V. All rights reserved.