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Aluminium pillared clays were synthesised under various experimental conditions starting from a sodium montmorillonite clay (Hithix). The influence of sonication, successive exchange and a constant pH during and after the intercalation process were investigated as important synthesis parameters in the optimisation of these materials. The concentration of aluminium in the pillaring solution, the ratio of Al/clay and the aging time and temperature were kept constant throughout this work. This optimisation is necessary in order to obtain high-quality Al-PILCs, as could be deduced from a theoretical study on the potential and limitations of pillared clay substrates. The ultrasonic treatment of the suspension during the synthesis is responsible for a significant increase in porosity. Despite the promising nature of the successive exchange technique, a reduction of the porosity is observed. Instead of a homogenisation process, an accumulation of aluminium in the interlayer space occurred. This expected homogenisation takes place when the synthesis of the pillared clay was carried out at constant pH. In this case, nitrogen BET surface areas of 458 m2/g and micropore volumes of 0.17 cm3/g were obtained after calcination of the intercalated clays at 400°C.