Acid activation and bleaching capacity of some Cameroonian smectite soil clays

Three Cameroonian clay materials with high smectite content were used for decolouration of palm oil with a clay/oil ratio of 2%. Particle size distribution, mineralogical and chemical analyses were done. The activation parameters (temperature, acid concentration and activation time) permitting the optimisation of their bleaching capacities have been determined. Their performances were compared to those of a commercial bleaching earth before and after acid activation. (C) 2007 Elsevier B.V. All rights reserved.