Naphthalene Adsorption and Desorption from Aqueous C₆₀ Fullerene

Abstract

The main purpose of this study was to characterize the adsorption and desorption interactions of naphthalene, a model environmental organic pollutant, with C60 fullerene. C60 fullerene was used as a model adsorbent for carbonaceous nanoparticles. Typical batch reactors were used to perform adsorption and desorption experiments. Adsorption and desorption of naphthalene to and from C60 fullerene solids in different aggregation forms was studied, where C60 was used as purchased, deposited as a thin film, or dispersed in water by magnetic mixing. Adsorption and desorption of naphthalene to activated carbon, a common sorbent, was also studied and compared with that of C60. It was found in this study that the enhanced dispersal of C60 could affect the adsorption of naphthalene by several orders of magnitude. A solid-water distribution coefficient of 102.4 mL·g-1 was obtained for adsorption of naphthalene to poorly dispersed C60, whereas (104.2 to 104.3) ml·g-1 coefficients were obtained for well-dispersed C60 samples. In addition, desorption of naphthalene from dispersed C60 samples into aqueous solutions was found to exhibit strong hysteresis. For the desorption over a period of 60 days, only about 11% of total naphthalene was desorbed from C60. Possible mechanisms for these observations are discussed.

Long-Lifetime and Asymmetric Singlet Oxygen Photoluminescence from Aqueous Fullerene Suspensions

“…As a contrast, another different aqueous nC 60 suspension was also prepared by using a familiar method in previous literature without organic solvents. The aqueous nC 60 , often termed as stir-nC 60 , was obtained by stirring 100 mg of C 60 powder in 200 mL of deionized water for 2 months via a magnetic stirrer at room temperature according to the method described by Cheng et al 23 Characterization of nC 60 Suspensions. The ultraviolet/visible (UV/vis) absorption spectra of our nC 60 suspensions were taken within a range of 200−900 nm by using a Jasco V550 spectrophotometer at room temperature and corrected for their corresponding solvent backgrounds.…”

Contaminant‐mobilizing capability of fullerene nanoparticles (nC60): Effect of solvent‐exchange process in nC60 formation

“…It has been proposed that the resistant desorption of hydrophobic organic contaminants from the aggregates of C 60 is due to the adsorption of organic molecules within the micropores of the C 60 aggregates [12,[26][27][28]. Thus, it might be reasonable to speculate that the two groups of nC 60 samples involved in the present study are of different microporous structures, resulting from the differences in aggregate formation between these two groups during the preparation of nC 60 samples.…”

“…A widely studied model fullerene material with mass production relevance [1], C 60, is highly hydrophobic and virtually insoluble in water, as the theoretical solubility of C 60 is only 1.3 Â 10 À5 mg/L [7]. Interestingly, C 60 can be made available in water as stable, nanoscale, colloidal suspensions (referred to as nC 60 herein) through various methods, such as solvent exchange, sonication, or long-term stirring without a solvent [8][9][10][11][12]. Nanoscale C 60 can be stable in aqueous environments for prolonged periods (months to years) and has a high potential for migration through soil and aquifer materials under common environmental conditions [13][14][15].…”

Application of fullerenes-extracted soot modified with ethylenediamine as a novel adsorbent of hexavalent chromium in water

“…The batch experiments were carried out using various initial concentrations of Cr(VI) (10,20,40,100,140, and 200 g mL The tested suspension was filtered through a cellulose membrane, and the filtrate was used for measuring the chromium concentration.…”

“…Carbon-based materials such as activated carbon, fullerene C60, carbon nanotubes, and graphene have been widely applied in water purification technology [9][10][11][12]. In particular, activated carbon, which is a micro-porous adsorbent, is very useful for the removal of various pollutants from water [13][14][15].…”