Ultrasonically Induced Sulfur-Doped Carbon Nitride/Cobalt Ferrite Nanocomposite for Efficient Sonocatalytic Removal of Organic Dyes

Abstract

The sulfur-doped carbon nitride/cobalt ferrite nanocomposite (SCN/CoFe2O4) was prepared via ultrasonication and studied for the sonocatalytic degradation of wastewater organic dye pollutants including methylene blue, rhodamine B, and Congo red. The X-ray photoelectron spectroscopy confirmed the presence and atomic ratios of S, C, N, Co, Fe, and O elements and their corresponding bonds with Co2+ and Fe3+ cations. The nanocomposite was found to have aggregated nanoparticles on a sheet-like structure. The bandgap energy was estimated to be 1.85 eV. For the sonocatalytic degradation of 25-ppm methylene blue at 20 kHz, 1 W and 50% amplitude, the best operating condition was determined to be 1 g/L of catalyst dosage and 4 vol % of hydrogen peroxide loading. Under this condition, the sonocatalytic removal efficiency was the highest at 96% within a reaction period of 20 min. SCN/CoFe2O4 outperformed SCN and CoFe2O4 by 2.2 and 6.8 times, respectively. The SCN/CoFe2O4 nanocomposite was also found to have good reusability with a drop of only 7% after the fifth cycle. However, the degradation efficiencies were low when tested with rhodamine B and Congo red due to difference in dye sizes, structural compositions, and electric charges.

Mesoporous Mn-Doped Fe Nanoparticle-Modified Reduced Graphene Oxide for Ethyl Violet Elimination: Modeling and Optimization Using Artificial Intelligence

“…The Freundlich equilibrium isotherm equation is an empirical relationship describing the multi-layer and heterogenous adsorption of adsorbed intermolecular interactions [84]. The linear and nonlinear forms of the Freundlich Equation (14) and Equation (15) are expressed as follows [90,91]:…”

“…q e = k F (c e ) 1/n (15) where k F = Freundlich isotherm constant (mg/g) and 1/n = adsorption intensity. The linear Temkin equation is expressed as follows [86]:…”

“…It is estimated that about 15% of the total world production of dyes is lost during the dyeing process, and this quantity is then released into the wastewater [8].Ethyl violet (EV) (C 31 H 42 ClN 3 , MW = 492.15 g/mol) is a typical cationic dye of triphenylmethane (Figure 1), which is toxic and has strong coloring ability and is difficult to degrade in the natural environment. Current approaches to detoxify the dye wastewater include Fenton or photo-Fenton oxidation, reduction by zero-valence metals, coagulation/flocculation, electrochemical oxidation, biological treatment, membrane filtration, ozonation, electrochemical degradation and adsorption [1,[9][10][11][12][13][14][15]. Among these options, zero-valence metals have attracted considerable attention in industries due to their ease of synthesis and operation, low cost and high adsorption capacity [9].Processes 2020, 8, x 2 of 31 and textile industries [4][5][6][7].…”

Synergistically enhanced solar light‐driven degradation of hazardous food colorants by ultrasonically derived MgFe2O4/S‐doped g‐C3N4 nanocomposite: A Z‐scheme system‐based heterojunction approach

“…[ 61 ] It has been predicted that, since the electronegativity of Sulfur (S) is lower than that of Nitrogen (N), doping of g‐C 3 N 4 with S atom could cause the re‐alignment of its conduction band (CB) and valence band (VB) edges. [ 62 ] As a consequence of which, change in band gap energy value is observed, which consequently results in improvement in its photoactivity. Additionally, the fabrication of nanostructured morphology is also proven to be capable of enhancing the activity of the photocatalytic material.…”

Barium/Cobalt@Polyethylene Glycol Nanocomposites for Dye Removal from Aqueous Solutions

“…Regarding all these, this type of dye is more commonly applied in industrial wastewater, with the azo dyes covering the 70% of total dyes worldwide [ 39 ]. Their decomposition in the natural environment, becomes difficult due to the presence of various functional groups that have toxic, mutagenic, and carcinogenic effects [ 40 ] and therefore must be removed from the effluent before being discharged into natural water systems [ 41 , 42 , 43 , 44 , 45 ].…”