title: Comparative study on the characteristics of fly ash and bottom ash geopolymers.
abstract: This research was conducted to compare geopolymers made from fly ash and ground bottom ash. Sodium hydroxide (NaOH) and sodium silicate (Na(2)SiO(3)) solutions were used as activators. A mass ratio of 1.5 Na(2)SiO(3)/NaOH and three concentrations of NaOH (5, 10, and 15M) were used; the geopolymers were cured at 65 degrees C for 48 h. A Fourier transform infrared spectrometer (FT-IR), differential scanning calorimeter (DSC), and scanning electron microscope (SEM) were used on the geopolymer pastes. Geopolymer mortars were also prepared in order to investigate compressive strength. The results show that both fly ash and bottom ash can be utilized as source materials for the production of geopolymers. The properties of the geopolymers are dependent on source materials and the NaOH concentration. Fly ash is more reactive and produces a higher degree of geopolymerization in comparison with bottom ash. The moderate NaOH concentration of 10 M is found to be suitable and gives fly ash and bottom ash geopolymer mortars with compressive strengths of 35 and 18 MPa.
authors: Department of Civil Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002, Thailand.
authors: Prinya
authors: P
authors: Chindaprasirt
authors: Chai
authors: C
authors: Jaturapitakkul
authors: Wichian
authors: W
authors: Chalee
authors: Ubolluk
authors: U
authors: Rattanasak
mesh_terms: D003252:Construction Materials / Q000032:analysis*; D017745:Incineration; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011108:Polymers / Q000737:chemistry*; D011210:Power Plants
chemical_list: D011108:Polymers