Calorimetric investigation of olivine carbonation as a mechanism for carbon sequestration

Abstract

According to numerous global-scale climate models, continuously increasing anthropogenic CO2 emissions will cause drastic consequences for climate. In an attempt to solve the on-going climate challenge, scientists have proposed various large-scale geological sequestration of CO2 from our atmosphere. Olivine carbonation is considered as a promising carbon sequestration method due to the long-term stability of product minerals, magnesite and quartz. Examining reaction rate and thermodynamics of olivine-CO2-H2O reaction to form magnesite and quartz can provide data needed to determine if this approach is too costly to be practical. The goal of this project is to use calorimeter to quantify the enthalpy and reaction rate of olivine carbonation reaction under conditions considered to be close to optimal for mineral carbonation. These data are needed to predict the heat generation under optimal temperature of 185oC and our limited pressure of 700psi. If this reaction is very exothermic and rapid, then this will help to lessen the energetic cost associated with achieving the high temperatures and pressures required to drive olivine carbonation. If this project is successful, the results will represent an important contribution to evaluating the utility of olivine carbonation as a carbon sequestration method. Significant exothermic reaction has been documented by heat flux changes and 16.7% of the initial CO2 is captured during the course of experiment under sealed calorimetric system. The heat production of olivine carbonation is still not yet measurable due to experimental artifacts that have prevented accurate heat flux measurements.