Development of Efflorescence Control Methods of Fly Ash Based Foam Geopolymers

Abstract

Since the environmental impacts of carbon emissions due to the cement production have started to be discussed, an alternative material has been sought. Geopolymers are new generation materials that are good candidates to be used instead of cement in the structures. Within the scope of geopolymer technology, the reuse of industrial by-products such as fly ash and blast furnace slag enable reuse of both the reduction of waste stock and the production of new generation material which excites the scientific world. However, various problems that have been focused on preventing the advancement of this technology. Efflorescence is a critical problem for the development of geopolymer technology. White residues formed on the surfaces of the materials produced from geopolymer wetting are referred to as efflorescence. Although it may seem like a visual problem in the initial stage, it may cause structural problems in later stages. Therefore, it is an issue that needs to be addressed. In this study, studies were made to prevent or minimize this problem. Efflorescence behavior of geopolymer foam samples prepared in different molarities and cured at different temperatures were investigated. It was determined that the samples prepared at high molarities and the samples cured at lower temperatures are more prone to the problem of efflorescence.