Research Abstract:
The potential environmental effects of
increasing atmospheric CO2
levels are of major worldwide concern. One
alternative for managing CO2 emissions is carbon sequestration: the capture and secure
confinement of CO2
before it is emitted to the atmosphere. Successful
technologies must be environmentally benign, permanent, economically viable,
safe and effective. As a result, their timely development represents a
significant challenge. 2
Unlike many other proposed CO2 sequestration technologies,
which provide storage, CO2
mineral
sequestration provides permanent disposal via geologically stable mineral carbonates
(e.g., MgCO3
). As such, mineral sequestration guarantees
permanent containment and avoids adverse environmental consequences and the
cost of continuous site monitoring. The major remaining challenge for CO2
mineral
sequestration is economically viable process development. This is the focus of
the CO2 Mineral Sequestration Working Group managed by DOE, which
also includes members from the Albany Research Center, Los Alamos National
Laboratory, National Energy Technology Laboratory, and Science Applications
International Corporation. Our goal is to
develop the necessary understanding of mineral carbonation reaction mechanisms
to engineer new materials and processes to enhance
carbonation reaction rates and reduce process and
serpentine minerals), due to their low cost and wide availability. In situ
dynamic high-resolution transmission electron microscopy has been used to
directly observe dehydroxylation/rehydroxylation-carbonation reaction processes
down to the atomic level. These studies are combined with detailed quantum
mechanical modelling and a variety of complementary studies to explore the
associated reaction mechanisms. Control of dehydroxylation/rehydroxylation
processes prior to and/or during carbonation have been found to dramatically
enhance carbonation reactivity. cost. Herein,
we focus on Mg-rich lamellar hydroxide feedstock materials (e.g., Mg(OH)
2 and serpentine minerals),
due to their low cost and wide availability.
In situ dynamic high-resolution transmission electron microscopy
has been used to directly observe dehydroxylation/rehydroxylation-carbonation
reaction processes down to the atomic level.
These studies are combined with detailed quantum mechanical modeling and
a variety of complementary studies to explore the associated reaction
mechanisms. Control of dehydroxylation/rehydroxylation
processes prior to and/or during carbonation have been found to dramatically
enhance carbonation reactivity.