A new approach to capture and store CO(2) by mineral carbonation using recyclable ammonium salts was studied. This process integrates CO(2) capture with mineral carbonation by employing NH(3), NH(4)HSO(4), and NH(4)HCO(3) in the capture, mineral dissolution, and carbonation steps, respectively. NH(4)HSO(4) and NH(3) can then be regenerated by thermal decomposition of (NH(4))(2)SO(4). The use of...

Coal combustion by-products such as fly ash (FA), brine and CO(2) from coal fired power plants have the potential to impact negatively on the environment. FA and brine can contaminate the soil, surface and ground water through leaching of toxic elements present in their matrices while CO(2) has been identified as a green house gas that contributes significantly towards the global warming effect...

Limestone is widely used in the construction industry to produce Portland limestone cement (PLC) concrete. Systematic evaluations of hydration kinetics, compressive strength development, and carbonation resistance are crucial for the rational use of limestone. This study presents a hydration-based model for evaluating the influences of limestone on the strength and carbonation of concrete. Firs...

In this work, the potential of CO₂ mineral carbonation of brucite (Mg(OH)2) derived from the Mount Tawai peridotite (forsterite based (Mg)₂SiO4) to produce thermodynamically stable magnesium carbonate (MgCO3) was evaluated. The effect of three main factors (reaction temperature, particle size, and water vapor) were investigated in a sequence of experiments consisting of aqueous acid leaching, e...

Carbonation of magnesiumand calcium-silicate minerals to form their respective carbonates is one method to sequester carbon dioxide. Process development studies have identified reactor design as a key component affecting both the capital and operating costs of ex-situ mineral sequestration. Results from mineral carbonation studies conducted in a batch autoclave were utilized to design and const...

Attrition of six different limestones was studied during calcium looping cycles for CO2 capture in a lab-scale fluidized bed apparatus. The tests were carried out under realistic conditions representative of a process with calcination in an oxy-firing environment. The focus of the activity was to investigate the effect of the presence of SO2 both in the calcination and in the carbonation stages...

The authors present a computational system that can deal with pH fluctuations and the decomposition of cementitious materials exposed to various environmental actions. In order to evaluate the fall in pH due to carbon dioxide, material models are developed for the transport and equilibrium of carbon dioxide, ionization, ion equilibriums, and the carbonation reaction based on thermo-dynamic theo...

EFFECTS OF CARBONATION ON THE MINERAL COMPOSITION OF CEMENT KILN DUST By Cecilia P. Anderson Department of Geological & Mining Engineering & Sciences

In this study, linear alkyl-benzene calcium sulfonate nanoparticles were made using linear alkylbenzene. Calcium sulfonate nanoparticles are widely used as an additive in a variety of engine oils and have cleansing, anti-wear and anti-oxidant properties and anti-corrosion properties. In this method, a sulfonation set up was constructed and sulfonation reaction was carried out both directly and ...