Frankincense-Based Functionalized Multiwalled Carbon Nanotubes with Iron Oxide Composites for Efficient Removal of Crystal Violet: Kinetic and Equilibrium Analysis

Abstract

In this study, novel adsorbents were developed by functionalizing multiwalled carbon nanotubes with frankincense (Fr-fMWCNT) and adding iron oxide (Fe 3 O 4 ) to the adsorbent (Fr-fMWCNT-Fe 3 O 4 ). The morphology, surface characteristics, and chemical nature of the synthesized samples were analyzed by using various characterization techniques. The prepared adsorbents were then applied for the elimination of the toxic dye, crystal violet (CV), from waterbased solutions by employing a batch adsorption method. The effectiveness of materials for the adsorption of CV was investigated by tuning various effective experimental parameters (adsorbent dosage, dye quantity, pH, and contact time). In order to derive adsorption isotherms, the Langmuir and Freundlich adsorption models were investigated and compared. The Fr-fMWCNT and Fr-fMWCNT-Fe 3 O 4 were found to remove 85 and 95% of the CV dye within 30 min of the adsorption experiment at pH 6, respectively. It was found that a pseudo-second-order reaction rate was consistent with the experimental adsorption kinetics. The equilibrium data demonstrated that the Langmuir model adequately explained the adsorption behavior of the CV dye on the Fr-fMWCNT and Fr-fMWCNT-Fe 3 O 4 surfaces, respectively. According to the Langmuir study, the highest adsorption capacities of the dye are 434 mg/g for Fr-fMWCNT and 500 mg/g for Fr-fMWCNT-Fe 3 O 4 . Remediation of the CV dye using our novel composite materials has not been reported previously in the literature. The synthesized Fr-fMWCNT and Fr-fMWCNT-Fe 3 O 4 adsorbents can be economical and green materials for the adsorptive elimination of CV dye from wastewater.

Hydrothermally synthesized Nb -doped TiO2 nanosheets for efficient removal of methylene blue dye on photocatalytic performance

“…Thus, removing of these contaminants from both aquatic and air environments is a prime objective for the scientific community and is necessary to save lives on Earth. In this direction, several studies are being conducted to eliminate or degrade the pollutants [7][8][9][10][11][12]. The use of the photocatalytic process is a well-known and widely adopted approach to addressing these global challenges.…”

“…In 1972, Fujishima and Honda made the initial report on the photocatalytic method of water splitting using TiO 2 . Generally, various photocatalyst materials, e.g., TiO 2 , MoO 3 , WO 3 , CdS, graphene-based materials, etc, show some promising results [7][8][9][10][11][13][14][15][16][17]. However, the efficiency of such photocatalyst materials is not very promising [18].…”