Design of experiment method to determine the influence of acid leaching on the preparation of porous glasses

Porous glass was prepared by phase separation. Raw materials were combined with powdered beer bottles to produce the base glass. The influence of acid leaching was analysed by the design of experiment (DOE) method. A DOE with five factors, two levels and two replications was implemented and the density and the percentage open porosity were measured by Archimedes' method. The five factors considered were acid type, acid concentration, acid temperature, acid treatment time and the ratio of the acid volume to the weight of glass samples. Of these factors acid concentration and acid/glass ratio were the key factors in determining the percentage open porosity as they had P values of less than 0.05 after the DOE analysis. The prediction profile plot and surface plot gave a controlled porosity range for the porous glass studied.