(cest2017_00649) Synthesis of geopolymers on fly ash from biomass combustion

摘要

Fly ash from biomass combustion aren't used innumerous economic branches. Their increased productionmake it necessary for researches to look for synthesis newproducts. The chemical composition of fly ash frombiomass combustion are similar to those of fly ash fromcoal, they can be used as raw material for geopolymersynthesis.The aim of the research was to assess feasibility ofgeopolimer synthesis from fly ash from biomass bygeopolymerisation method. The effect of temperature,curing time and the ratio of fly ash to alkaline activator(sodium hydroxide and sodium water glass) impact in theformability of geopolymers mass were investigated.On the basic of the research investigations, optimalconditions of geopolimerisation have been determined. Wehave also found, that optimal conditions for synthesis ofgeopolymers on fly ash from biomass combustin arefollowing: temperature - 20 °C, curing time 17 hours andthe ratio of fly ash [g] to alkaline activator [cm3] - 50:50.The surface morphology and chemical compositionanalysis (before and after geopolimerisation) wereexamined for the obtained geopolymers by SEM-EDSmethods. The UV-VIS-NIR spectra (before and aftergeopolimerisation) were performed. They showed, thatreceived geopolymers possess optical and photocatalyticproperties.