In the CO2 emission remediation by means of alternative geopolymers as substitutes for cements

Abstract

Here we present a geopolymer as a sustainable alternative for cements. The geopolymer binder is presented in a dry form (dry mixing method). The geopolymer has demonstrated to be ideal candidate to mitigate the typical carbon footprint emissions of cements, such as Portland. The potential global benefits include a reduction of up to 1480 million tons of CO2 per year when compare with Portland cement. In this design, it is proposed an alkali-activated cementitious material that is made out of a mix of silica-rich sand and sodium carbonate. Such sand has 80–85 wt% SiO2 and 15–20 wt% mixed rock grain. This composition is processed at temperatures around 850 °C that is 650 °C less than that for Portland cements. One of the benefits is that the use of limestone is eliminated resulting in such reductions in CO2 emissions. The emission analysis is carried during a calcination process used to analyze the decarbonation or CO2 emission step. This work presents a complementary characterization of the products including an infrared spectroscopy analysis and thermogravimetry.