Next Article in Journal
Lauric Acid Hybridizing Fly Ash Composite for Thermal Energy Storage
Next Article in Special Issue
Property and Microstructure of Waterborne Self-Setting Geopolymer Coating: Optimization Effect of SiO2/Na2O Molar Ratio
Previous Article in Journal
The Evidence of Decisive Effect of Both Surface Microstructure and Speciation of Chalcopyrite on Attachment Behaviors of Extreme Thermoacidophile Sulfolobus metallicus
Previous Article in Special Issue
The Role of Clay Swelling and Mineral Neoformation in the Stabilization of High Plasticity Soils Treated with the Fly Ash- and Metakaolin-Based Geopolymers
Open AccessArticle

Experimental Evaluation of Efficient Si Dissolution from Perlite at Low Level Activator’s Concentration

School of Mining and Metallurgical Engineering, National Technical University of Athens, 157 80 Athens, Greece
Author to whom correspondence should be addressed.
Minerals 2018, 8(4), 160;
Received: 20 March 2018 / Revised: 29 March 2018 / Accepted: 30 March 2018 / Published: 14 April 2018
(This article belongs to the Special Issue Geopolymers)
This paper deals with the Si dissolution of fine perlite in alkaline solutions for the determination of the SiO2/Na2O mass ratio in the aqueous phase of geopolymer slurries. In the present work, the effect of the main synthesis parameters such as NaOH concentration and curing temperature on the setting time of the paste were studied. The obtained results showed that the inorganic polymer pastes present fast hardening at low concentrations of NaOH solutions for both 70 and 90 °C. This observation was also identified by the Si dissolution study of perlite pastes as a function of different concentrations of NaOH solutions and different solid to liquid ratios of the slurries, under a constant temperature. The optimum synthesis conditions for geopolymer pastes proved to be a low initial NaOH concentration in the alkaline phase (2–4 M NaOH), where the fast hardening of the paste was attributed to the high SiO2/Na2O mass ratio, enhancing the polycondensation phenomena and promoting the geopolymerization process. View Full-Text
Keywords: geopolymerization; inorganic; perlite; alkali activation geopolymerization; inorganic; perlite; alkali activation
Show Figures

Figure 1

MDPI and ACS Style

Tsaousi, G.-M.; Douni, I.; Panias, D. Experimental Evaluation of Efficient Si Dissolution from Perlite at Low Level Activator’s Concentration. Minerals 2018, 8, 160.

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.

Article Access Map by Country/Region

Back to TopTop