... lime and cement. The gypsum is used as a catalyst and for optimizing the properties of AAC. The silica is obtained from silica sand, fly ... , water, and aluminum powder or paste. The slurry is poured into moulds where a chemical reaction occurs, the reaction between aluminum and ... 10 to 12 hours. The result is a non-organic, non-toxic, airtight material that can be used for wall, floor, and roof ...