Aluminosilicate are often produced from kaolin with a kaolin bond in the formulation intended to increase the thermal strength of the product. Because kaolin formulations do not sinter well, investigation of methods for increasing the density of kaolin is highly relevant. The density can be increased by increasing the degree of dispersion. An additive which improves sinterability would be especially effective. Bentonite with its high plasticity and reactive surface meets these requirements to a certain extent. Four formulations of the porcelain tableware were prepared in different percentage from 0 to 15 wt.% of calcic bentonite. The mass loss and shrinkage of different formulations were measured by using the following thermal analysis such as: Differential thermal analysis (DTA), thermal gravimetric analysis (TGA) and dilatometric analysis. Its density, water absorption, total porosity and the flexural strength were also measured at different temperatures between 1250 and 1400°C. It was found that the bentonite added to the formulation increases the strength of the product and reduces the total porosity to 3.35% by increasing the degree of dispersion during the grinding of the components, thereby improving the sintering process of the formulation. On one hand, the weight loss, shrinkage and sintering time were decreased. On the other hand, the thermal resistance and flexural strength were increased at 1380°C for 10 wt.% of bentonite content.

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Today, recycling industrial waste plays a major role in our society. Waste is used as additive in the production of a certain number of products. It enables to reduce the costing price per piece and to enhance some of the properties of the material, and to reduce pollution problems. To meet the various criteria, and manufacturing requirements of contemporary ceramic tile and bring a solution to our environment, an addition of waste glass from lamps public lighting and neon (cullet) is incorporated in various ceramic masse for substituted a feldspar. A comparative study is made between the properties obtained with each type of waste on the one hand and the other with the properties of tile produced in the industry. It was found that the tiles made with waste glass lighting lamps offer higher mechanical strength than that obtained with the feldspar and a good agreement between the shard - enamel. Although the value of strength obtained with the waste of neon is lower than that obtained with the first type of glass. The latter always remains higher than that of industrial value.

Several parameters governed the rheological properties as well as the nature of the constituents, to the process of implementation. One of the major solution is to master the milling time which is responsible for the fineness of the grains, which in turn, conditioned the correct handling of the sintering mechanism, and allows highlight of the correlation between the size of the powders and the rheological properties. The introduction of a powder in a liquid induces changes in the interface of the solid phase when it passes from the vapor phase, to the liquid phase. To improve this understanding, we studied the influence of these parameters on the good dispersion of particles and more particularly the grain size. To do this, four mixtures composed of clay, kaolin, feldspar and sand were considered. The difference between each mixture, is the substitution of kaolin by feldspar with a decreased of kaolin (8%) compared to the initial rate. Each mixture was to undergo three grinding duration (-1 h, 30 min, 1 h and 2 h). The analysis of the rheological properties allowed us to note that the best flow was obtained with mixtures C3, C4, C5, corresponding to a grinding duration of 1 h 30 min. We also observed a clear correlation between the grinding time and viscosity. After drying of the suspensions, the powders obtained are grounded according to three types of particle sizes (0.25 -1 and 1.25 mm) then pressed in the form of ceramic tiles physical-mechanical, analyses were performed on the cooked products. After optimization and comparative study between the different mixtures, it was found that the M3 mixture, with grain size of 1.25 mm provides the best products. The measured values are in agreement with the requirements of manufacturing standards and offer a higher mechanical strength to the tiles manufactured industrially.

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