Direct Adsorption Isotherms of AEAs and Fly Ash: α-Olefin Sulfonate and Combination Admixtures

Abstract

The direct adsorption isotherm test provides a direct measurement of the air entraining admixtures (AEAs) adsorption by fly ash in concrete. This method was developed and tested using a popular Vinsol resin admixture. In this paper, the direct adsorption isotherm test was performed on two other commonly used AEAs of different chemical compositions to verify the applicability of this method to AEAs of other chemical natures. The results showed that, as in the case of the Vinsol resin admixture, the AEAs partitioned between the solid and liquid phase, the partitioning coefficient changed with changing the AEA concentration, and this method was able to quantify the fly ash adsorption capacity based on the Fruendlich adsorption model. Also, in order to present a practically useful approach for the concrete/fly ash industry, the isotherms results of the three AEAs were correlated to the fly ash iodine number test results. Concrete producers can use these correlations to determine the AEA adsorption capacity, and the AEA dosage adjustment using the fly ash iodine number without the need to perform the direct adsorption isotherm test.

CO2 Mineralization and Utilization Using Various Calcium-Containing Wastewater and Refining Slag via a High-Gravity Carbonation Process

“…In order to simultaneously achieve CO 2 fixation and waste utilization, , CCUM could utilize the industrial alkaline wastes such as steelmaking slag, fly ash, and bottom ash rather than the chemical sorbents. Those materials normally contained abundant metal oxides including calcium, iron, aluminum, and magnesium oxides, which could be considerably utilized as CO 2 adsorbent, supplementary cementitious materials (SCMs), and lightweight aggregate . Those industrial alkaline wastes consisted of high heavy metal contents and active species to limit the applications, which might impact the environment and human health.…”

“…Those materials normally contained abundant metal oxides including calcium, iron, aluminum, and magnesium oxides, which could be considerably utilized as CO 2 adsorbent, 3 supplementary cementitious materials (SCMs), 4 and lightweight aggregate. 5 Those industrial alkaline wastes consisted of high heavy metal contents and active species to limit the applications, which might impact the environment and human health. The active species (e.g., free-CaO) might gradually absorb moisture from the air and cause the expansion in the cement product.…”

Integrated CO2 Fixation, Waste Stabilization, and Product Utilization via High-Gravity Carbonation Process Exemplified by Circular Fluidized Bed Fly Ash

“…These materials are generally rich in metal oxides, such as calcium, iron, aluminum, and magnesium oxides. Therefore, a large diversity of utilization can be considered, such as CO 2 adsorbent, lightweight aggregate, supplementary cementitious materials (SCMs), composites, and antibacterial cool pigment . However, some of those solid wastes are classified as hazardous materials because they may contain large amounts of heavy metals and bring air particulate pollution, which might result in severe impacts on the environment and human health.…”

Valorization of an Electronic Waste-Derived Aluminosilicate: Surface Functionalization and Porous Structure Tuning

“…Aluminosilicate materials have received an ever-increasing amount of attention because of their large internal surface area and pore volume, tunable pore size distribution, high thermal stability, and unique ion exchange capability . Fabrication of these materials with desired textural properties and their surface modification to tailor certain functionalities stand out as utmost crucial areas of research, as they find a wide array of applications in electrochemistry, catalysis, − support, , the cement industry, chromatography, dehumidification, antioxidants, fertilizers, sensors, and sorbents. − …”