Construction Wastes as Raw Materials for Geopolymer Binders

It has been shown that geopolymerization can transform a wide range of waste aluminosilicate materials into building materials with excellent chemical and physical properties such as fire and acid resistance. In this research work, geopolymerization of construction waste materials with different alkali-activators based on combinations of Na2SiO3 and NaOH has been investigated. A number of systems were designed and prepared with water-to-dry binder ratio, silica modulus, and sodium oxide concentration were adjusted at different levels and setting time and 28-day compressive strength were studied. The results obtained reveal that construction wastes can be activated using a proportioned mixture of Na2SiO3 and NaOH resulting in the formation of a geopolymer cement system exhibiting suitable workability and acceptable setting time and compressive strength. Laboratory techniques of Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) were utilized for studying molecular and microstructure of the materials.