The reduction of carbon dioxide (CO2) emissions from cement production by the additionof supplementary cementitious materials (SCM’s) has garnered significant interest. To predict the
CO2 uptake of systems with SCM’s, an experimental setup for measuring the effective diffusion
coefficient of CO2 in concrete was developed. A MATLAB script was written to calculate the
diffusion coefficient through curve-fitting of Fick’s second law. Six mixtures which represented a
ternary binder composition varying in quantity of Portland cement, fly ash, and portlandite were
tested after 1, 4, and 7 days of curing. CO2 uptake was measured by X-ray diffraction (XRD) and
thermogravimetric analysis (TGA). Porosity and pore saturation were measured by solvent exchange. Results of the experimental diffusion setup were consistent with these tests, and
changes in methods to increase the setup’s reliability are discussed.