Solvent-Free Synthesis of Phosphonic Graphene Derivative and Its Application in Mercury Ions Adsorption

Abstract

Functionalized graphene was efficiently prepared through ball-milling of graphite in the presence of dry ice. In this way, oxygen functional groups were introduced into material. The material was further chemically functionalized to produce graphene derivative with phosphonic groups. The obtained materials were characterized by spectroscopic and microscopic methods, along with thermogravimetric analysis. The newly developed material was used as an efficient mercury adsorbent, showing high adsorption efficiency. The adsorption isotherms were fitted using Freundlich and Langmuir models. The adsorption kinetics were fitted with pseudo-first order and pseudo-second order models. Adsorption selectivity was determined in the presence of cadmium ions and nickel ions. The presence of mentioned bivalent ions in the solution did not affect mercury adsorption efficiency.

Recent Advances in Ball-Milled Materials and Their Applications for Adsorptive Removal of Aqueous Pollutants

“…The adsorption isotherm, in accordance with the Langmuir model, shows that the adsorption of pollutants on ball-milled materials is monolayer coverage with a similar energy of adsorption sites [165,166]. The alignment of adsorption kinetics with the pseudo-second-order model indicates that the ball milling brings numerous active sites to materials, and the adsorption kinetics stays in correlation with the availability of adsorption sites on the surface of adsorbents rather than adsorbate concentrations in bulk solution [121]. The best fit of the Redlich-Peterson and Elovich model on Ni(II) adsorption by the ball-milled biochars (BM-BCs) suggested that it was heterogeneous, involving multi-mechanism adsorption processes [86].…”

“…And then, defects were changed to oxygen-containing functional groups due to the participation of O 2 from the atmosphere [32]. Olszewski et al [121] indicated that ball milling graphite with CO 2 not only introduced oxygen-containing functional groups into the edges of graphite planes but also prevented the materials from uncontrollable destruction and remained the layered structure with lower defects compared to the one ball milling in air. This method eliminated the use of solvents without by-products and was conductive to converse carboxylic groups into un-hydrolyzed phosphonic groups by reacting with PCl 3 to obtain phosphonic graphene derivatives (PGO) (Figure 4b).…”

“…The peaks shifted from 1594 cm −1 to 1620 cm −1 , associating with aromatic C=C stretching frequency, indicating some sort of interaction between Cr species and the aromatic π network [127]. Olszewski et al [121] presented that the adsorptive data of Hg(II) by the PGO-fitted Langmuir model and the maximum adsorption capacity were 82.2 mg/g through the interaction between Hg(II) and phosphonic groups. The presence of Cd(II) and Ni(II) did not affect Hg(II) adsorption, resulting from the enhanced interaction between phosphonic acid (soft base) and Hg(II) (soft acid) and the fast adsorption rate of Hg(II).…”

Porous ZnCl2-Activated Carbon from Shaddock Peel: Methylene Blue Adsorption Behavior

“…In comparison, adsorption technology is widely used due to its low cost, ease of operation, and high efficiency [ 14 ]. Metal oxides [ 15 ], carbon materials [ 16 ], metalorganic frameworks (MOF) [ 17 ], graphene [ 18 ], zeolites [ 19 ], and polymers [ 20 ] have all been used as adsorbents in the treatment of polluted water. Among them, activated carbon (AC) is one of the most commonly used adsorbents, which is one kind of low-cost adsorbent, and the corresponding adsorption performance is primarily determined by the carbon pore structure, which is derived by the carbon resource and carbonization process.…”

Solvent-Free Mechanochemical Synthesis and Characterization of Nickel Tellurides with Various Stoichiometries: NiTe, NiTe2 and Ni2Te3

“…The mechanochemical method, also known as mechanical alloying, is a convenient solid-state processing technique in which the precursor powders are exposed to repeated welding, fracturing, and re-welding in a high energy ball mill. The method has been developed in the 1970s for the fabrication of nickel- and iron-base superalloys for applications in the aerospace industry [ 32 , 33 ] and is nowadays widely used in the processing of advanced materials like alloys [ 34 ], bimetallic nanocatalysts [ 35 ], oxide materials [ 36 , 37 ], carbon-based materials [ 38 , 39 , 40 ], etc. The first reports of mechanochemical synthesis of metal chalcogenides date back to the 1990s, and since then, a number of nanosized sulfides, selenides, and tellurides have been prepared using this method.…”