Next Article in Journal
Diffusive Uptake Rates of Volatile Organic Compounds on Standard ATD Tubes for Environmental and Workplace Applications
Next Article in Special Issue
Addition of WEEE Glass to Metakaolin-Based Geopolymeric Binder: A Cytotoxicity Study
Previous Article in Journal
Biodesulfurization of Petroleum Distillates—Current Status, Opportunities and Future Challenges
Previous Article in Special Issue
Mechanical Behaviour of Soil Improved by Alkali Activated Binders
Article Menu
Issue 4 (December) cover image

Export Article

Open AccessArticle
Environments 2017, 4(4), 86;

Porous Geopolymer Insulating Core from a Metakaolin/Biomass Ash Composite

CNR-ISTEC, National Research Council-Institute for Science and Technology for Ceramics, via Granarolo, 64-48018 Faenza, Italy
CertiMaC ScarL, via Granarolo, 62-48018 Faenza, Italy
ENEA SSPT/PROMAS TEMAF, Laboratory of Materials Technologies Faenza, Department for Sustainability/Division Sustainable Materials, Italian National Agency for New Technologies, Energy and Sustainable Economic Development, via Ravegnana, 186-48018 Faenza, Italy
Author to whom correspondence should be addressed.
Received: 20 October 2017 / Revised: 27 November 2017 / Accepted: 28 November 2017 / Published: 1 December 2017
(This article belongs to the Special Issue Environmentally Friendly Geopolymer Composites)
Full-Text   |   PDF [3888 KB, uploaded 1 December 2017]   |  


Ashes derived from the combustion of vegetal and animal biomass still represent a mostly unexplored secondary raw material for the production of alkali-activated materials, given their peculiar chemical nature. In this work, calcium phosphate biomass ashes were successfully used as partially reactive fillers in a metakaolin-based geopolymer composite to produce, by direct foaming, sustainable and lightweight boards with thermal insulating properties. The investigated materials were obtained by activating a blend of metakaolin and biomass ash in a weight ratio of 1: 1 and foamed with the addition of H2O2 in measure of 5 wt. %, to maximize the volume of disposed ash and ensure adequate properties to the material at the same time. The obtained geopolymer composite was characterized by microstructural, chemical-physical, mechanical and thermal analysis: the obtained results showed that biomass ash and metakaolin well integrated in the microstructure of the final porous material, which was characterized by a density of about 310 kg/m3 and a thermal conductivity of 0.073 W/mK at a mean test temperature of 30 °C, coupled with an acceptable compressive strength of about 0.6 MPa. Dilatometric and thermogravimetric analysis, performed up to 1000 °C, highlighted the thermal stability of the composite, which could be regarded as a promising material for low-cost, self-bearing thermal insulating partitions or lightweight cores for thermostructural sandwich panels. View Full-Text
Keywords: geopolymer; biomass ash; composite; thermal insulation; sandwich panel; waste materials geopolymer; biomass ash; composite; thermal insulation; sandwich panel; waste materials

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Natali Murri, A.; Medri, V.; Papa, E.; Laghi, L.; Mingazzini, C.; Landi, E. Porous Geopolymer Insulating Core from a Metakaolin/Biomass Ash Composite. Environments 2017, 4, 86.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Environments EISSN 2076-3298 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top