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A porcelana de ossos - bone china - é uma cerâmica de corpo especial de grande dureza e translucidez exclusivamente fabricada na Inglaterra e em outras poucas partes do mundo, mas não no Brasil. Suas matérias-primas são compostas por aproximadamente metade de cinza de ossos, além de caulim e feldspato. O trabalho apresenta a obtenção e caracterização de cinza de ossos a partir de ossos bovinos com o objetivo da fabricação de porcelanas. No processo de preparação da cinza de ossos envolve o uso de autoclave, descarnagem manual, calcinação e moagem dos ossos. As condições de preparação foram estudadas em função das condições de calcinação, moagem e lavagem do osso. A calcinação foi estudada através de análises térmicas e difração de raios X de diferentes partes do animal. O pó obtido foi caracterizado por análises químicas, medida de granulometria por difração de laser, e microscopia eletrônica de varredura. Os resultados mostraram que a matéria-prima obtida neste trabalho possui propriedades similares das originalmente utilizadas nas indústrias inglesas com baixo teor de ferro e partículas coloidais e que podem ser calcinadas a temperaturas inferiores a 1000 °C.

Hydraulic fracturing is a very important technique to increase the productivity and recovery of oil reservoirs with low pressure or high depth. The hydraulic fracturing technique is a method of well stimulation in which liquid under high pressure is pumped down a well to fracture the reservoir rock adjacent to the wellbore. Propping agents are used to keep the fractures/cracks open. They can be made from the reject of mineral extraction processes when they present specifics characteristic. The aim of this paper is the evaluation of the use of industrial rejects to the development of ceramic synthetic proppants that are resistant to chemical corrosion and high mechanical strength in aqueous acid and salt water environment. In this study, industrial rejects from nickel sulfide ore flotation (grey mud - GM), red mud (RM) from Bayer process and black mud (BM) from Caron processing of nickel was used as raw material for the production of ceramic synthetic proppants. The material processing was performed through drying, milling, pressing, sintering and characterizing raw material. Several characterization techniques such as X-ray powder diffraction (XRD), Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), high temperature dilatometry and compression strength test were performed after sintering to evaluate the technological potential of recycling these metallurgical and mineral rejects. Mechanical properties were improved after sample sintering. The results show that it is possible to manufacture ceramics of high strength and resistance to acidic/salt water environment as a result of processing minerals reject.

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