Loyford Muchui Mugambi

About Loyford Muchui Mugambi

Affiliation
Norwegian University of Science and Technology (NTNU)

Project
Understanding the Fundamental Mechanism of C-(A)-S-H Carbonation

Background
Materials Chemist with MSc. in Materials Chemistry from Meru University of Science and Technology, Kenya. My interest is in advancing innovative and sustainable solutions for the cement industry through cutting-edge research in cement science.

Research topic
My research project is focused on studying the carbonation mechanisms of the main hydrated cement phases. This is to ensure faster advances in the use of carbonated recycled concrete fines (cRCF) not only as a reactive SCM, but also for CO2 sequestration.

The project involves synthesizing different cement hydrates (C-S-H, C-A-S-H and AFt) and studying their enforced wet carbonation using CO2 and sodium carbonate solution, varying the exposure solution in terms of pH and alkali content to see their effect on the structure and composition of carbonation products. Solid characterization involves X-ray Diffraction (XRD), Thermogravimetric analysis (TGA), specific surface area (BET), Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR), while solution analysis includes pH, conductivity and Inductively coupled plasma optical emission spectroscopy (ICP-OES). A kinetic model is built to describe the carbonation process and the rate-limiting steps. Solubility studies are then carried out to determine the stability of produced gels under different conditions of pH and alkalis. Finally, to give insights into the application of cRCF as SCM, selected alumina-silica gels from carbonation are blended with cement and hydration studied using isothermal calorimetry.