Smectite clay from the Sabga deposit (Cameroon): mineralogical and physicochemical properties

The physicochemical and mineralogical characterization of the < 250 µm particle-size fraction from six the clay-rich samples from the Sabga deposit (North-west, Cameroon) were carried out in order to evaluate their potential applications. Analyses revealed that the major clay mineral was dioctahedral smectite along with small amounts of kaolinite in three clay samples. Cristobalite, feldspars, ilmenite and heulandites were also found as accessory minerals. A Li-saturation test (Greene-Kelly test) revealed the montmorillonitic nature of the smectite component. The chemical composition of the bulk clays consists of (66-70%) SiO2, (13-16%) Al2O3 and (2-7%) Fe2O3. These clays present mineralogical (high montmorillonite content) and physico-chemical (cation exchange capacity (CEC): 38 to 46 meq/100g and specific surface areas ranging from 33 to 90 m2/g). These physical and chemical properties are fully compatible with potential uses in environmental applications. After some pretreatment (purification, chemical modification), these materials could also be used in refining edible oil as adsorbent, waste water treatment and wine technology.