Activation of Persulfates by Graphitized Nanodiamonds for Removal of Organic Compounds

Abstract

This study introduces graphited nanodiamond (G-ND) as an environmentally friendly, easy-to-regenerate, and cost-effective alternative catalyst to activate persulfate (i.e., peroxymonosulfate (PMS) and peroxydisulfate (PDS)) and oxidize organic compounds in water. The G-ND was found to be superior for persulfate activation to other benchmark carbon materials such as graphite, graphene, fullerene, and carbon nanotubes. The G-ND/persulfate showed selective reactivity toward phenolic compounds and some pharmaceuticals, and the degradation kinetics were not inhibited by the presence of oxidant scavengers and natural organic matter. These results indicate that radical intermediates such as sulfate radical anion and hydroxyl radical are not majorly responsible for this persulfate-driven oxidation of organic compounds. The findings from linear sweep voltammetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, and electron paramagnetic resonance spectroscopy analyses suggest that the both persulfate and phenol effectively bind to G-ND surface and are likely to form charge transfer complex, in which G-ND plays a critical role in mediating facile electron transfer from phenol to persulfate.

Catalysis by hybrid sp2/sp3nanodiamonds and their role in the design of advanced nanocarbon materials

“…168 The activity is higher than those of typical metal oxide particles, such as Lee et al proposed instead a non-radical oxidation pathway, based on PDS activation and phenol removal via electron transfer from phenol to PDS. 169 BNDs only facilitate the electron transfer and reactant adsorption. Lee et al indicated that radical intermediates such as SO 4 À and OH are not involved in this persulfate-driven oxidation of phenol.…”

“…Lee et al indicated that radical intermediates such as SO 4 À and OH are not involved in this persulfate-driven oxidation of phenol. 169 More recently, a series of BNDs with different graphitized degrees (annealed at different temperatures) were investigated by Duan et al (Fig. 12a).…”

Activation of Peroxymonosulfate by Oxygen Vacancies-Enriched Cobalt-Doped Black TiO2 Nanotubes for the Removal of Organic Pollutants

“…11−19 Transition-metal ions with multiple valence state are most frequently used for activation of PMS without the need for external energy inputs (e.g., UV light and electricity). 20…”

Heterogeneous degradation of refractory pollutants by peroxymonosulfate activated by CoOx-doped ordered mesoporous carbon

“…It was worth noticing that the activation of persulfate by various carbonaceous materials, such as activated carbon [18], reduced graphene oxide (rGO) [19][20][21][22][23], carbon nanotubes (CNTs) [24][25][26][27][28], ordered mesoporous carbon (OMC) [29] and nanodiamond [30,31], had attracted much attention because of their environmental-friendly and high efficiency. Due to its high surface area, accessible mesopores and large pore volume, OMC had been applied in many areas such as adsorbents [32], catalysts and supports [33,34], and electrode materials [35].…”