This study investigated the effect of solid‐to‐liquid ratio (0.4–1.0) on the properties of geopolymer, in which some metakaolinite was replaced by solar panel waste glass (0–40%). The experimental results indicate that geopolymer containing 10% solar panel waste glass at a solid‐to‐liquid ratio of 1.0 has higher compressive strength than geopolymer without solar panel waste glass at 1 and 7 days of curing. Thus, geopolymer containing 10% solar panel waste glass is more suitable than geopolymer without solar panel waste glass for practical applications. Furthermore, the porosity of the geopolymer declined as the density increased. The experimental results showed that the degree of reaction of the geopolymer increased with the solid‐to‐liquid ratio. The Fourier transform infrared spectroscopy spectra revealed that the principal peaks from the geopolymer corresponded to the Si—O—Al bonds. The scanning electron microscopy of the geopolymer indicated that the main structure of a geopolymer that contained solar panel glass with a higher solid‐to‐liquid ratio was more compact and homogenous, which is consistent with the higher density and lower porosity. The experimental results showed that the solid‐to‐liquid ratio affected the properties of geopolymer considerably. In addition, we observed some positive influence of the solar panel waste glass on the compressive strength of metakaolinite‐based geopolymer; however, it was limited to the early compressive strength. Furthermore, the degree of reaction of the geopolymer that contained 10% solar panel waste glass was similar to that of the metakaolinite‐based geopolymer when the positive influence on the compressive strength diminished. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 797–803, 2013

This investigation elucidates the mechanical characteristics of geopolymer containing solar panel waste glass. With the SiO2/Na2O molar ratio (S/N = 0.75, 1.0, 1.25, 1.5, 1.75), the percentage of metakaolinite that is replaced by so-lar panel waste glass (0- 40%), and the curing time of 1, 7, and 28 days as the study variables, the porosity, density, setting time, compressive strength, and flexural strength of the geopolymer were evaluated. The morphology of geopolymer was examined using Scanning Electron Microscopy (SEM), and its microstructural properties were examined through Fourier transform infrared spectroscopy (FTIR) analysis. The results demonstrate that the S/N molar ratio significantly influences the mechanical and morphological characteristics of geopolymers. The geopolymer containing solar panel waste glass with an S/N of 1.75 had the greatest compressive strength. The intensity of the peak that represented Si-O-Al bonding of the geopolymer containing solar panel waste glass increased with the S/N. Analysis of the sample morphology revealed that the microstructures of stronger samples were more homogeneous and appeared denser. Furthermore, solar panel waste glass has the potential to partially replace metakaolinite as a geopolymer material, and to exhibit favorable me-chanical characteristics.

This study examined the characteristics of geopolymer with solar panel waste glass. After 28 days of curing, the compressive strengths of the geopolymer samples containing 10 mass % and 20 mass % solar panel waste glass were 63.3± 1.8 and 49.1 ± 2.2 MPa, respectively. The geopolymer sample with 10% solar panel waste glass exhibited a stronger reaction than that with 20% solar panel waste glass, and the strength decreased as the amount of solar panel waste glass increased. Thermo-gravimetric and differential thermal analysis (TG/DTA) results showed that the mass loss of geopolymer after heating declined as the amount of solar panel waste glass increased. The principal peaks in the Fourier transformation infrared spectroscopy (FTIR) spectra correspond to the Si-O-Al bond in geopolymer. Scanning electron microscopy (SEM) observations indicated that the microstructures of the stronger samples were more homogeneous, and the microstructures of geopolymer with 10% solar panel waste glass did not exhibit substantial deterioration. The experimental results indicate that solar panel waste glass has the potential to serve as a partial replacement of metakaolinite and exhibits favorable mechanic characteristics.