Annals of Civil Engineering and Management(ACEM)

Department of Chemical Engineering, Dalhousie University, Canada

Publications

• Literature Review   
  Intelligent Carbon Reactive Cement Systems Using Dynamic CO2 Absorption During Concrete Hydration
  Author(s): Chinenye Elizabeth Onumadu*
  
  Cement production accounts for ≈8% of anthropogenic CO2 emissions, yet the material itself could become a carbon sink if CO2 absorption is engineered into its hydration sequence. Here we introduce an intelligent carbon-reactive cement system that dynamically absorbs CO2 during defined curing stages rather than post-hardening. We blended ordinary Portland cement with 20% reactive MgO and exposed specimens to a three-stage CO2 regime: ambient air (0–30 min), 5% CO2 (30 min–4 hr, coinciding with the acceleration period of hydration), followed by air (4–24 hr). Compared to constant CO2 exposure or no CO2, the dynamic protocol achieved 22% CO2 uptake by mass of MgO (vs. <5% in constant exposure) within 24 hours, with no surface carbonation crust or microcracking. X-ray diffraction revealed nesquehonite and calcite formed exclusively during the dynamic absorption .. Read More»
  

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