CO2 conversion to calcium and magnesium carbonates has garnered considerable attention since it is a thermodynamically downhill pathway to safely and permanently sequester large quantities of CO2. This seminal work performed at The National Energy Technology Laboratory in Albany (NETL-Albany) reports the conversion of calcium-and magnesium-bearing silicate minerals, such as olivine [(Mg, Fe)2Si...

Cement-based wasteforms are among the most commonly used waste disposal and site remediation options. However, concrete knowledge of the processes controlling long-term performance of the wasteforms is lacking. This research evaluates the effect of carbonation on cementitious wasteforms. Wasteforms were reacted with carbon dioxide for a prolonged period and then subjected to leaching tests. Ion...

During the production of concrete, cement, water, aggregate, and chemical and mineral admixtures will be used, and a large amount of carbon dioxide will be emitted. Conversely, during the decades of service life of reinforced concrete structures, carbon dioxide in the environment can ingress into concrete and chemically react with carbonatable constitutes of hardened concrete, such as calcium h...

This work presents experimental results regarding the use of pure nickel nanoparticles (NiNP) as a mineral carbonation additive. The aim was to confirm if the catalytic effect of NiNP, which has been reported to increase the dissolution of CO₂ and the dissociation of carbonic acid in water, is capable of accelerating mineral carbonation processes. The impacts of NiNP on the CO₂ mineralization b...

Carbonation of concrete is a phenomenon that causes corrosion of steel in reinforced concrete structures, and is recognized as an important problem for ensuring the durability of structures. Against this background, many researchers have proposed methods for predicting the progress of concrete carbonation under various environments. In this study, the authors aim to improve the accuracy and to ...

The conversion of thermally pretreated CaO along successive carbonation/calcination cycles has been investigated, as a ected by looping-calcination conditions, by means of Thermogravimetric Analysis (TGA). Sorbent samples have been subjected in-situ to a thermal preheating program based on Constant Rate Thermal Analysis (CRTA) by virtue of which decarbonation is carried out at a low controlled ...

7 Even though an increasing number of pilot-scale plants are demonstrating the potential ef8 ficiency of the Ca-looping technology to capture CO2 at a commercial level, a still standing 9 matter of concern is the loss of carbonation reactivity of the regenerated CaO by calcination, 10 which is expected to be particularly marked at realistic conditions necessarily implying a high 11 CO2 partial ...

Carbon nanotubes (CNTs) have excellent mechanical properties and can be used to reinforce cement-based materials. On the other hand, the reaction product of carbonation with hydroxides in hydrated cement paste can reduce the porosity of cement-based materials. In this study, a novel method to improve the strength of cement paste was developed through a synergy of carbon nanotubes decorated with...

In this paper, the effects of carbonation on pore structure of blended pozzolan cement pastes were investigated. Ordinary Portland cement OPC was partially replaced with ground palm oil fuel ash POA , ground rice husk ash RHA and classified fine fly ash FA . The strength, total porosity, specific surface area, and pore size distribution were tested. In general, incorporation of pozzolans increa...

The current low-cost process for mineral carbonation involves the direct carbonation of a slurry of magnesium or calcium silicate mineral with supercritical CO2. The process is currently limited by the slow reaction kinetics of the carbonation reactions, and in particular the slow dissolution rates of the silicates in weakly acidic conditions. Enhancing the dissolution rate in weakly acidic con...