PREPARATION OF FOAMED GEOPOLYMERS USING DEALUMINATED KAOLIN WASTE

Abstract

Cheap raw materials, mainly industrial wasteswere used to prepare geopolymer bricksto be used in thermal insulation in the construction industry. The samples were prepared by replacing calcined kaolin byground clay bricks(homra)and using milk of lime resulting from the manufacturing of acetylene together withminor addition of caustic soda as activators;pores were created inside the bricks by adding aluminum trimmings assembled from workshops of aluminum frames manufacturing. Alum wastewas also made to replace homrawith different proportions. Physical, mechanical and thermal properties of the bricks were investigated as function of aluminum added and homra substitution by de-aluminated kaolin. The recommended composition for the preparation ofthermal-insulating geopolymer bricks was obtained by substituting 15% homrawith alum with 5% aluminum trimmings. The resulting bricks showed a total density of 1000 kg.m-3 ,compressive strength after 28 days = 1.5 MPa and thermal conductivity coefficient = 0.26 W.m-1.K-1.