Effect of Additives and Sintering Temperatures on Production of Cordierite – Mullite Support

Abstract

This research aims at studying the effect of additives and sintering temperatures on production of cordierite – mullite support. This work starts with the preparation of the cordierite support from kaolin, ball clay, talcum and alumina by solid casting method and varying temperature in heat treatment of cordierite support and fired kaolin for use as additives at 1200 1300 and 1400°C. It was found that the optimum temperature used to produce the cordierite phase in the cordierite support and to produce the maximum mullite phase from kaolin was at 1400°C. The preparation of the cordierite – mullite support was then started by varying the mixture composition among the raw materials that cause the cordierite phase to additives, i.e. the fired kaolin at 1400°C to 3 formulas, namely CM-1 for 80:20, CM-2 for 70:30 and formula CM-3 60:40. After sintering at 1400°C, cordierite support and the cordierite – mullite support, CM-1, CM-2 and CM-3 have a modulus of rupture 58.24 ± 1.36 MPa, 45.35 ± 1.55 MPa, 38.33 ± 2.63 MPa and 30.94 ± 2.02 MPa; respectively. All formula showed a coefficient of linear thermal expansion (CTE) of lower than 5x10-6 1/°C and showed a softening point (Ts) at temperature of 1,318, 1,258 and 1,265°C, respectively. Result of thermal shock resistance test found that samples of cordierite – mullite support of formula CM-3 showing a maximum mullite phase indicated an excellent thermal shock resistance property.  Keywords :  cordierite, cordierite – mullite, coefficient of linear thermal expansion, thermal shock resistance