[01] Namarig Abdalla Mohamed Ahmed, Department of Chemical Engineering, Faculty of Engineering, University of Khartoum, Khartoum, Sudan. [02] Mustafa Abbas Mustafa, Department of Chemical Engineering, Faculty of Engineering, University of Khartoum, Khartoum, Sudan.

The main aim of this work is to develop regression models for the characterization of deactivated fluid catalytic cracking catalysts (FCC) as a result of metal deposition and coke. The regression analysis and ANOVA was performed in Microsoft Excel. Four dependent variables were used including activity, surface area, average particle size and apparent bulk density. The independent variables ranged over twelve parameters covering physical and chemical properties of FCC spent catalyst. The methodology used to develop the models is the backward elimination procedure which is dependent on p-value of parameters with a significant level of 0.1. The regression models for activity and surface area were obtained with R² values of 0.73 and 0.53 respectively, while models for average particle size and apparent bulk density were obtained with R² values of 0.75 and 0.62 respectively.

Catalyst, Deactivation, Regression Models

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