Mechanisms of surfactant adsorption on non-polar, air-oxidized and ozone-treated carbon surfaces

High capacity mercury adsorption on freshly ozone-treated carbon surfaces

“…As can be seen, ozone imparts hydrophilicity (reduces foam index) and the effect does not significantly decay over time. This is consistent with a previous study [16] which suggested that a wide variety of polar oxygencontaining group contribute to hydrophilicity, and most groups are stable to desorption below about 300°C. In contrast, the sites responsible for Hg capture are likely to be a small subset of these groups that are energetic, oxidizing, and labile.…”

“…Air oxidation at 300°C and 500°C as well as treatment with hydrogen peroxide (see Materials and Methods section) led to carbon blacks with capacities within 30% of the capacity of untreated sample. Both air oxidation and hydrogen peroxide treatment have been shown to generate a variety of different oxygen containing surface functional groups on carbon surfaces [16,23], but these "common" surface oxides are apparently not responsible for the high-activity Hg capture reported here. The dramatic but unstable surface activation is unique to ozone and worthy of further study.…”

“…The capacity increase for the microporous activated carbon is much less than for the nonmicroporous carbon black and mesoporous carbon, likely due to micropore blockage by oxygen containing functional groups. Ozonolysis of microporous carbons has been shown to leads to a decrease in surface area because of pore blockage [16,22].…”

“…Oxidation imparts hydrophilicity to carbon surfaces [16,17], which is desirable for Hg-sorbents used in power station applications, where contamination of fly ash by hydrophobic activated carbon adversely affects the properties of fly ash concrete [16,18]. In previous experiments from our laboratory, ozone treatment did increase the hydrophilicity of activated carbon as desired, but did not enhance the performance of the activated carbon as mercury sorbent, and under some conditions degraded the performance.…”

Effect of Surface Modification on Mechanical Properties of Quartz Fiber Reinforced Boron Doped Silicone Resin Composites

“…Up to now, many efforts have been devoted to modify carbon fibers for improving the interfacial properties between the carbon fibers and the matrix, such as plasma treatment, [11][12][13] radiation treatment, [14,15] chemical modifications. [16][17][18] In contrast, little work has been done to modify the surface of quartz fibers. The sizing agent is one of the simple and efficient approaches that can increase the reactivity between fibers and matrix by enhancing the physical and chemical properties of the fiber surface.…”