Development of fly ash-based geopolymers using powder sodium silicate activator

Geopolymer manufacturing by means a ready-mix procedure using powder sodium silicate as activator is described in this paper. Its characteristics are compared with conventional geopolymers using aqueous sodium silicate. Degree of reaction, mercury intrusion porosity and compressive strength were measured at different curing times. Three durability tests were carried out. The geopolymer obtained using powder activator showed slightly lower mechanical properties and better durability results than those found for geopolymers based on aqueous activators. In addition, the manufacture of geopolymers based on powder silicate was easier and simpler than the more common procedure using sodium silicate solutions, so the ready-mix manufacturing could be an alternative to produce geopolymers.