Synthesis of intumescent materials by alkali activation of glass waste using intercalated graphite additions

Porous alkali activated materials (AAM), can be obtained from waste glass powder and slag mixtures by alkali activation with NaOH solution. To obtain an adequate porous microstructure, the hardened AAM pastes were thermally treated at temperatures ranging between 900°C and 1000°C, for 60 or 30 minutes. Due to the intumescent behaviour specific for this type of materials, an important increase of the volume and porosity occurs during the thermal treatment. The partial substitution of waste glass powder with slag, determines the increase of compressive strength assessed before (up to 37 MPa) and after (around 10 MPa) thermal treatment; the increase of slag dosage also determines the increase of the activation temperature of the intumescent process (above 950°C). The high porosity and the specific microstructure (closed pores with various shapes and sizes) of these materials recommend them to be utilised as thermal and acoustical insulation materials.

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Influence of the gypsum dehydration temperature and alkali additives on the properties of anhydrite cement

Science of Sintering ◽

10.2298/sos1002233l ◽

2010 ◽

Vol 42 (2) ◽

pp. 233-243 ◽

Cited By ~ 1

Author(s):

V. Leskeviciene ◽

I. Sarlauskaite ◽

D. Nizeviciene ◽

N. Kybartiene

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Compressive Strength ◽

Crystalline Structure ◽

Alkali Activation ◽

Glass Waste ◽

X Ray ◽

Gypsum Dehydration ◽

Scanning Electron ◽

Sem Analyses

While dehydrating gypsum with additives at the temperatures of 800?C and 900?C the influence of alkali additives on both the crystalline structure of anhydrite and properties of anhydrite binder was investigated. The industrial and household wastes including other lowcost materials were used as additives. Having heated them with gypsum the anhydrite with alkali activation properties was obtained. The properties of such substances were evaluated using the methods of chemical, diffractive X-ray scanning and scanning electron microscopy (SEM) analyses. Some additives, e.g. 5 % ground glass waste, were found to increase crystal agglomerate formation of anhydrite binder, accelerate the hydration process of anhydrite and double the compressive strength of hydrated samples compared to samples without additives.

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FT-IR Study, Thermal Analysis, and Evaluation of the Antibacterial Activity of a MK-Geopolymer Mortar Using Glass Waste as Fine Aggregate

Polymers ◽

10.3390/polym13172970 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2970

Author(s):

Giovanni Dal Poggetto ◽

Antonio D’Angelo ◽

Ignazio Blanco ◽

Simona Piccolella ◽

Cristina Leonelli ◽

...

Keyword(s):

Antibacterial Properties ◽

Alkali Activation ◽

Fine Aggregate ◽

Bacterial Strains ◽

Glass Waste ◽

Gram Negative ◽

E Coli ◽

Urban Solid Waste ◽

Ft Ir ◽

Ir Study

Food containers made from glass are separately collected from urban solid waste at 76% in most parts of Europe. The cullet glass finds its way to re-melting, while the debris is often disposed of. With this contribution, we suggest an upcycling process where glass debris is simply ground without any washing operation and added to an alkali-activated paste. Metakaolin-based geopolymer mortar added with coarsely ground glass waste as fine aggregate has been prepared via alkali activation with NaOH and Na-silicate. After 7, 14 and 28 days of room temperature curing time, the 3D geopolymer network was investigated by Fourier-transform infrared spectroscopy (FT-IR). Vibrational spectra revealed the geopolymerization occurrences, results which have been supported by both FT-IR deconvoluted spectra and thermogravimetric analysis (TGA). Finally, the antibacterial properties were investigated against both gram-negative (E. coli) and gram-positive (E. faecalis) bacterial strains. The results suggest the ability of the 28 days cured geopolymers to inhibit the growth of the gram-negative bacterium assayed.

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