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Abstract Porous thermostable ceramic materials with low temperature coefficient of linear expansion (TCLE) are required for fabricating refractories, thermal insulation, catalyst supports and filters for hot liquid gases used in industry. One of these materials is cordierite based ceramic. Cordierite is well-known to display low thermal expansion and in turn has an excellent thermal shock resistance when it is subjected to rapid thermal changes. There is no doubt that this material is offered as one of the potential ceramic filters that meet the demand of highly efficient particulate removal from hot gas stream in a number of industrial process points. These includes preparation of combustion off gases for reuse across secondary turbines, removal of particulate from hydrocarbon processing gas streams above the dew point, filtering of gases from incineration of reuse and disposal facilities, removal and/or recovery of catalyst from off gases, and others. A large numbers of investigations dealt with the using of numerous techniques in synthesis of cordierite as well as porous cordierite ceramic with the using of various starting materials or even from analytical grade oxide powder. Meanwhile, the using of secondary resources or waste materials can bring a higher output of cordierite at lower costs than the traditional one, and make a break-through in raw materials as well as technology. This dissertation focused on the possibilities of utilization of the solid waste materials (silica fumes and aluminum slag) in the preparation of cordierite based ceramic as well as fabrication of porous cordierite body. The thesis consists of four main chapters. Chapter one deals with the introduction and literature review. The literature review part cover all the processes used in synthesis of cordierite based ceramics. In addition, it contains all the processes used in fabrication porous ceramic body via various techniques. Meanwhile, the importance of using solid state reaction during cordierite synthesis among all other process as well as the importance of using replica technique during porous body fabrication was reported. Chapter two concerned with the experimental work. In this chapter, the experimental procedures during this investigation were clearly described. On the other hand the characterization tools used during investigation were illustrated. Chapter three focused on the results of the dissertation and its discussion. The most important remarks conducted from this part could be summarized as follows:- 1- With the using of aluminum slag during synthesis of cordierite with a mixture of quartz and talc, sintering temperature of 1300oC with sintering time of 2hr was regarded as the most appreciate sintering conditions for this batch mixture. On the other hand, using of 0.2 wt% sodium silicate (based on the dry solids) at pH of 8 was considered the most appropriate conditions for obtaining a well-dispersed suspension of this powder mixture. The characterization of porous cordierite body produced with replica technique revealed the suitability of using the obtained body in the application concerning dust filtration. 2- With the using of silica fumes during synthesis of cordierite with a mixture of bauxite and talc, sintering temperature of 1350oC with sintering time of 2hrs was regarded as the most appreciate sintering conditions for this batch mixture. A well-dispersed suspension from this mixture was obtained with the using of 0.2 wt% sodium silicate (based on dry solids) at pH of 8. Porous cordierite body with large spherical interconnected pores includes small irregular pores was obtained via replica technique. This structure is suitable for application in dust collection purpose. 3- During the usage of the two waste together (silica fumes and aluminum slag) with talc, the most appreciate sintering condition for this batch mixture was found to be 1325oC sintering temperature and 2hrs sintering time. However, 0.2% sodium silicate (based on dry solids) at suspension pH of 8 was regarded as the most appreciate conditions for obtaining a well-dispersed suspension from this mixture. The obtained porous body from this mixture proved to be suitable for dust collection purpose. |