Synthesis of Alum from Discarded Aluminium Beverage Cans

Abstract

This study provides a chemical process that recycles waste aluminium cans to alum crystals that has plenty applications in industry today. The study was performed with concentrated acidic and alkaline solution containing principal components K+ and SO42- ions. It involved the dissolution of aluminium can in KOH solution, neutralization by H2SO4 solution and cooling crystallization to produce alum crystals. Emphasis was placed on the percentage yield of alum and recovery of aluminium from waste aluminium can to useful product. The result obtained the highest yield of 80% when 1.5M of KOH solution and 9M of H2SO4 solution were used with 5 g of aluminium beverage cans. When the concentration of KOH and H2SO4 solution was increased, the yield of alum production was also increased. It was found that the crystallization process was effective in recovering aluminium in the form of alum from waste aluminium beverage cans.