High capacity mercury adsorption on freshly ozone-treated carbon surfaces

Manchester, Shawn; Wang, Xuelei; Külaots, Indrek; Gao, Yuan; Hurt, Robert H.

doi:10.1016/j.carbon.2007.12.019

Cited by 37 publications

(16 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Oxidative treatments produce a variety of functional groups including epoxide, peroxide, hydroxyl, carbonyl, and carboxylate. Ozonolysis forms epoxides or ozonides, the latter typically decomposing to stable carbonyl groups [34, 35]. Epoxide, hydroxyl, and some (closed) peroxides are addition products, which like aryl-sulfonate, disrupt local pi-conjugation but allow three backbone bonds to remain.…”

Section: Discussionmentioning

confidence: 99%

Biodurability of single-walled carbon nanotubes depends on surface functionalization

Liu

Hurt

Kane

2010

Carbon

Self Cite

151

136

View full text Add to dashboard Cite

Recent research has led to increased concern about the potential adverse human health impacts of carbon nanotubes, and further work is needed to better characterize those risks and develop risk management strategies. One of the most important determinants of the chronic pathogenic potential of a respirable fiber is its biological durability, which affects the long-term dose retained in the lungs, or biopersistence. The present article characterizes the biodurability of single-walled carbon nanotubes using an in vitro assay simulating the phagolysosome. Biodurability is observed to depend on the chemistry of nanotube surface functionalization. Single-walled nanotubes with carboxylated surfaces are unique in their ability to undergo 90-day degradation in a phagolysosomal simulant leading to length reduction and accumulation of ultrafine solid carbonaceous debris. Unmodified, ozone-treated, and aryl-sulfonated tubes do not degrade under these conditions. We attribute the difference to the unique chemistry of acid carboxylation, which not only introduces COOH surface groups, but also causes collateral damage to the tubular graphenic backbone in the form of neighboring active sites that provide points of attack for further oxidative degradation. These results suggest the strategic use of surface carboxylation in nanotube applications where biodegradation may improve safety or add function.

show abstract

Section: Discussionmentioning

confidence: 99%

Biodurability of single-walled carbon nanotubes depends on surface functionalization

Liu

Hurt

Kane

2010

Carbon

Self Cite

151

136

View full text Add to dashboard Cite

show abstract

“…Elemental and oxidized Hg are absorbed in particulate matter such as fly ash and unburned carbon and have a tendency to associate with the particles in flue gas to form particulate-bound mercury. Although Hg is introduced as an elemental vapor, it is consistently bound on particles in the oxidized form [22]. Mercury capture in boilers and existing control devices indicates very little mercury removal within a pulverized coal-fired boiler [11].…”

Section: Total Hg and Pollution Statusmentioning

confidence: 99%

Mobility and contamination assessment of mercury in coal fly ash, atmospheric deposition, and soil collected from Tianjin, China

Zheng

et al. 2011

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Samples of class F coal fly ash (levels I, II, and III), slag, coal, atmospheric deposition, and soils collected from Tianjin, China, were analyzed using U.S. Environmental Protection Agency (U.S. EPA) Method 3052 and a sequential extraction procedure, to investigate the pollution status and mobility of Hg. The results showed that total mercury (HgT) concentrations were higher in level I fly ash (0.304 µg/g) than in level II and level III fly ash and slag (0.142, 0.147, and 0.052 µg/g, respectively). Total Hg in the atmospheric deposition was higher during the heating season (0.264 µg/g) than the nonheating season (0.135 µg/g). Total Hg contents were higher in suburban area soils than in rural and agricultural areas. High HgT concentrations in suburban area soils may be a result of the deposition of Hg associated with particles emitted from coal-fired power plants. Mercury in fly ash primarily existed as elemental Hg, which accounted for 90.1, 85.3, and 90.6% of HgT in levels I, II, and III fly ash, respectively. Mercury in the deposition existed primarily as sulfide Hg, which accounted for 73.8% (heating season) and 74.1% (nonheating season) of HgT. However, Hg in soils existed primarily as sulfide Hg, organo-chelated Hg and elemental Hg, which accounted for 37.8 to 50.0%, 31.7 to 41.8%, and 13.0 to 23.9% of HgT, respectively. The percentage of elemental Hg in HgT occurred in the order fly ash > atmospheric deposition > soils, whereas organo-chelated Hg and sulfide Hg occurred in the opposite order. The present approach can provide a window for understanding and tracing the source of Hg in the environment in Tianjin and the risk associated with Hg bioaccessibility.

show abstract

“…In general, the currently available technologies for the reduction of heavy metals contamination include precipitation (Mauchauffée and Meux 2007), reverse osmosis (Mohsem-Nia et al 2007), ion exchange (Verma et al 2008), coagulation (El Samrani et al 2008) and adsorption (Gupta et al 1999(Gupta et al , 2003(Gupta et al , 2004(Gupta et al , 2005. Adsorption is considered an appropriate technology for the treatment of liquid effluents with high pollutant load (Gupta and Ali 2006;Manchester et al 2008;Legrouri et al 2005). However, its application on great scale, as in industrial plants for example, may be relatively expensive.…”

Section: Introductionmentioning

confidence: 98%

Mercury removal from aqueous solution by adsorption on activated carbons prepared from olive stones

et al. 2011

View full text Add to dashboard Cite

The textural characterization of a series of activated carbons prepared from olive stones, by carbonization at different temperatures (400, 550, 700 and 850°C) and thermal activation with CO 2 , has been investigated using N 2 adsorption at −196°C and CO 2 adsorption at 0°C. The effect of pre-oxidation of the carbonized precursor has also been studied, using temperature-programmed decomposition (TPD), to evaluate the effect of oxygen content of the chars in the performance of the obtained activated carbons for mercury removal. The adsorption of Hg(II) cations from aqueous solutions at room temperature by the prepared activated carbons was studied. Experimental results show that all samples exhibit a large microporosity (pore diameter below 0.56 nm). The amount of surface oxygen groups increased after pre-oxidation treatment, this enhancing the Hg(II) uptake (up to 72%). It can be concluded that these groups make the support more hydrophilic, thus providing a more efficient adsorption of Hg(II). The formation of a great amount of surface oxide groups such as carboxyl, phenol and lactone alters the surface charge properties of the carbon, this enhancing the surface-Hg(II) interaction.

show abstract

High capacity mercury adsorption on freshly ozone-treated carbon surfaces

Cited by 37 publications

References 37 publications

Biodurability of single-walled carbon nanotubes depends on surface functionalization

Biodurability of single-walled carbon nanotubes depends on surface functionalization

Mobility and contamination assessment of mercury in coal fly ash, atmospheric deposition, and soil collected from Tianjin, China

Mercury removal from aqueous solution by adsorption on activated carbons prepared from olive stones

Contact Info

Product

Resources

About