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The Boom Clay is an important raw material for the Belgian structural clay products industry. It can be divided into several lithological sub-units. In order to obtain an insight in the parameters which characterize these different units, and which affect the overall properties of the clay, a detailed chemical, physical and mineralogical analysis was carried out. Pearson correlation coefficients were calculated between the variables, which were then placed in four correlation groups: a quartz/clay mineral group, a reducing component group, a carbonate group and a feldspar group. This treatment of the data allowed three analysis parameters to be selected: <2 µm fraction, organic carbon and CO2. The other variables could be calculated fairly accurately from these by means of regression lines.

The conversion of gibbsite to (pseudo)boehmite has been studied by thermogravimetry, X-ray diffractometry and scanning electron microscopy, supplemented by density and surface area measurements. As a reference for desired product properties, commercial pseudoboehmite, laboratory synthesized seudoboehmite and autoclaved boehmite have also been studied. Three kinds of heating processes have gee, applied : In an oven, in a steam flow and under vacuum. All experiments were carried out at 220°C.Prolonged heating under vacuum resulted in a corn lete conversion of gibbsite to (pseudo)boehmite. The product still differs too much from commercial pseucfoboehmite to be a valuable alternative. Also takin into account the manufacturing implications of vacuum heating, this process seems hardly feasible on ayarge scale.

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Pseudoboehmite powder is widely used as a precursor material for the manufacturing of shaped catalyst carriers.The conversion of pseudoboehmite to gamma alumina is determined to a large extent by the manufacturing route of the powder. Physical properties like particle size and shape, crystallinity, porosity, etc. have a distinct influence on the thermal behaviour. This thermal and physical characterization has allowed to translate basic powder properties into the industrial practice of catalyst carrier manufacturing. Unit operations as mix-mulling, extrusion, drying and calcination are clearly affected by powder characteristics.After processing, it provides unique properties as high surface area, porosity and strength.