Abstract
The objective of this work encompasses the application of aluminium foil waste for preparing alumina (Al2O3), by precipitation. The response surface approach is developed for the produced ?-Al2O3 phase. Experiments were performed according to a 32 factorial design to evaluate the effects of hydrochloric acid (HCl) concentration, sodium hydroxide (NaOH) that was used as precipitation agent, as well as the calcination temperatures on the purity and yield. The effect of the two independent variables on the response variables was studied by response surface plots and contour plots generated by the Design-Expert software. The desirability function was used to optimize the response variables. The compatibility of the resulted purity and yield of the prepared alumina was further investigated and analysed by EDX test that results more than 97% for the three samples which calcined at three different temperatures. The study of the evolution of crystalline phases of obtained powders was accomplished through different studies. The morphology of the obtained alumina was tested by using SEM test. The observed responses taken agreed with the experimental values, and ?-Al2O3 phase was produced with less experimental trials, and a high yield was achieved with the concept of formulation by design.
