OPTIMISATION OF CARBON DIOXIDE (CO2) SEQUESTRATION USING SANDCRETE-TALC COMPOSITE

Abstract

Global interest on CO2 emission reduction has triggered alternative cement formulation using non-classical raw materials. This work presents a study on optimisation of CO2 uptake by sandcrete-talc composite material. The morphology, mineralogical and oxide composition of the materials were characterized using Scanning Electron Microscopy (SEM), X-ray Diffractormeter (XRD) and X-ray fluorescence (XRF).The result obtained from XRF indicate that sand consist 50.213% SiO2.and 16.001% Si with other diminish amount of oxide and metals, while mineral talc consist of 48.932% SiO2 and 24.86% MgO and cement contain 52.911% CaO, 15.122% Ca and 11.55% SiO2 with minute quantities of Alkalis and other metallic oxides. The mathematical model for the determination of CO2 concentration and compressive strength of sandcrete-talc composite was developed and optimized by the application of two-level four factorial design. The result showed that as curring age increases with increase in talc and sand components at constant cement component, the CO2 concentration and compressive strength also increases. The developed predicted model showed that the optimal concentration of CO2 and compressive strength obtained were 0.289mol/dm3 and 3.506N/mm2 respectively after 28 day curing at an ambient condition.