Abstract
Egyptian calcium hydroxide byproduct, produced as a waste material during preparation of acetylene gas, causes various ecological problems. The present work had the aim of utilising this waste material as a source of calcium oxide in the production of refractory calcium aluminate cement. Two types of calcium aluminate cement (pure and commercial grade) were prepared, by mixing calcium hydroxide waste material with pure calcined alumina and calcined bauxite respectively. The cements were prepared by sintering at 1500-1550degreesC for 3 h. The mineralogical compositions of anhydrous and hydrated cements were investigated by XRD. Also, thermal analysis and microstructure were used to identify the hydrated phases. The study revealed good cementing, sintering, mechanical, and refractory properties of the manufactured cements, enabling their use in high temperature applications (> 1500degreesC) in the case of pure cement, and in moderate temperature applications (< 1500degreesC) in the case of commercial cement. (C) 2002 IoM Communications Ltd. Published by Maney for the Institute of Materials, Minerals and Mining.