CEMGLASS: Towards CO2-utilizing cement: Assessing the characteristics and performance of nanostructured glass for cements

The Problem

Cement manufacture plays a major role in global CO2 emissions accounting for 5-8% of anthropogenic emissions. Mg-carbonate based cements are studied as a carbon-negative option to the current paradigm. The global feedstocks of Mg-silicate minerals are sufficient to capture all anthropogenic CO2 emissions for the foreseeable future. However a major bottleneck is the low reactivity of the raw materials, Mg-silicates.

Challenges

Building on the PI’s previous work on phase-separated glasses and self-organized nanostructures, this project will study Mg-silicate glass compositions to yield novel cement precursors. Generally glasses made from silicate minerals have poor reactivity due to their low modifier content. Here, by introducing phase separated nanostructures to the glasses by self-organization their reactivity can be increased without expensive additives or high-energy treatments.

The objectives of the project are 1) to synthesize phase separated glasses with tuneable nanostructures 2) to establish a link between glass morphology and reactivity, and 3) to characterize the cementitious CO2-utilizing reaction products and durability. We will use state-of-the art characterization methods to accurately assess the nanostructured glasses and their reaction kinetics through thermodynamic and quantum chemical modelling. Finally, initial feasibility of the cement concept will be assessed using industrial grade minerals.

The Solution

Taken together, a highly-reactive magnesium silicate glass will be synthesized that will react in the presence of water and minor activators, and is able to solidify and form durable reaction products, and capture CO2. The work conducted in CEMGLASS aims to observe the basic phenomena that can be exploited in CO2-utilizing cements and assess its initial feasibility. If the nanostructured glass concept is successful, it would have massive carbon capture potential.