Composition and Refractory Properties of Mixtures of Moroccan Silica-Alumina Geomaterials and Alumina

Abstract

Five mixtures (M1 to M5) of silica-alumina geomaterials and two varieties of alumina (A P and A R ) were used for the elaboration of mullite refractory materials between 1500˚C and 1600˚C. An X-ray diffraction (XRD) analysis showed that the refractory samples are composed of mullite, corundum and silica. The length of the mullite crystals was measured by a method of image analysis of scanning electron microscopy (SEM). Chemical and mechanical properties of these materials were investigated and correlated with their microstructure. Resistance towards Acid Attack test showed that the refractory samples present good resistance, as well as, the alumina powder A R obtained from waste of silica-alumina bricks proves to be efficient for an eventual use.

Characterization of elaborated Moroccan mullite to improving porous refractories quality

“…The following mineralogical phases were identifi ed for the red clay (ArgS): illite as the principal mineral, with kaolinite and quartz. Other secondary minerals phases found in this clay are hematite and dolomite [13].…”

“…Kaolin clay (ArgK) was selected as the clay raw material for high refractoriness of the products. This clay results from hydrothermal alteration of alkali granite of Oulmès, located in the center of the Moroccan Meseta [12,13]. Red Clay (ArgS) is a very fi ne-grained silt of lower Cretaceousage, rich in clay minerals and poor in carbonates.…”

“…Very large outcrops of these clay deposits exist in the region of Safi . Clays of this region are intensely exploited by the industrial ceramists for the manufacture of bricks and tiles [13,14]. Silica Sand (SabM) used in this study comes from an artisanal quarry, located at 3 km SE of the MechraaHammadi Dam.…”

“…Silica Sand (SabM) used in this study comes from an artisanal quarry, located at 3 km SE of the MechraaHammadi Dam. The sands appear as a thin layer of a white-pink and friable rock, belonging to the series of limestone of the upper Jurassic [13].…”

The effects of bauxite, metakaolin, and porosity on the thermal properties of prepared Iraqi clays refractory mortars

“…Refractory ceramics have special characteristics such as high resistance to thermal shock, high resistance to melting, with low thermal conductivity and a low thermal expansion. Furnace linings wall was considered one of the most important applications of refractory materials [1].…”