Removal Of Methyl Orange Dye Research Articles

Enhanced photocatalytic removal of methyl orange dye employing SiO2/Mn2O3 based nanocatalyst under visible light

Surface water contamination by dye pollutants is a global environmental concern. The treatment of effluent from textile waste using metal oxide-based photocatalysts is a widely employed approach owing to its efficacy and simplicity. Herein, the synthesis and fabrication of novel visible radiation receptive manganese oxide and mesoporous silica nanocomposites (Mn2O3/SiO2) is described. Surface morphology of nanocomposites using scanning electron microscopy (SEM) displayed spherical shaped agglomerated structure. The chemical composition of nanocomposites was examined by using energy dispersive x-ray (EDX) analysis respectively indicating the presence of respective elements. Structural analysis was carried out by using XRD spectroscopy, while optical properties were evaluated by employing UV–visible spectroscopy. The photocatalytic activity of pure Mn2O3 and SiO2 nanoparticles as well as their nanocomposites with two different ratios Mn2O3/SiO2 (1:3) and Mn2O3/SiO2 (3:1) were evaluated by using methyl orange (MO) as a model dye. The band gap energy of Mn2O3/SiO2 (1:3) and Mn2O3/SiO2 (3:1) nanocomposite was 2.39 eV and 1.69 eV respectively. The nanocomposites exhibited improved photocatalytic efficiency as compared to pure nanoparticles as a function of pH and mixing ratio. For instance, at pH 7.0, Mn2O3/SiO2 (1:3) nanocomposite has depicted maximum degradation efficiency of 68 % for degradation of MO as compared to Mn3O4/SiO2 (3:1) nanocomposite, Mn3O4 and SiO2 nanoparticles. However, at pH 2.0 Mn2O3/SiO2 (3:1) nanocomposite had shown maximum degradation efficiency of 99 % as compared to Mn2O3/SiO2 (1:3), Mn2O3 and SiO2 nanoparticles. The degradation reaction followed pseudo first order kinetics. At pH 7.0, the rate constant values of nanocomposites i.e. Mn2O3/SiO2(1:3) and Mn2O3/SiO2(3:1) comes out to be 4.68 × 10−3 min−1 and 2.49 × 10−3 min−1 respectively. At pH 2.0, the rate constant values calculated for Mn2O3/SiO2(1:3) nanocomposite and Mn2O3/SiO2(3:1) nanocomposite was 4.91 × 10−3 min−1 and 1.24 × 10−2 min−1 respectively. The easy fabrication of these nanocomposites coupled with facile tuning of their properties make them suitable contenders for efficient dye degradation in wastewater treatment.

Methyl Orange Dye Removal by Dimethylamine Functionalized Graphene Oxide

Graphene oxide (GO) functionalized with dimethylamine (DMA) was successfully prepared using a facile technique. GO was first synthesized using the modified Hummers method, followed by chemical functionalization with DMA in the presence of an electrophilic linker, i.e., epichlorohydrin (ECH). FTIR analysis of the end product ascertains the successful synthesis of GO as well as its functionalization with DMA. Typical characteristic peaks attributed to GO and DMA are clearly discernible in the spectrum. The effect of pH, adsorbent dosage, dye concentration, and contact time towards methyl orange (MO) dye removal was studied and reported herein. In summary, enhanced adsorption of methyl orange was observed for DMA functionalized GO compared to GO alone. 90% removal was observed with 10 mg/L of MO concentration, pH = 2 at temperature 25 °C and 5 mg of adsorbent. Modelling study shows that the pseudo-second-order kinetic model and Freundlich isotherm model provide better fitness to the experimental data.

Adsorption isotherms studied on synthesized corn cob-based activated carbon as an adsorbent for removal of methyl orange dye from aqueous solution

Adsorption isotherms studied on synthesized corn cob-based activated carbon as an adsorbent for removal of methyl orange dye from aqueous solution

Environment benign Ghee residue – titania based adsorbent for quick removal of methyl orange dye

Environment benign Ghee residue – titania based adsorbent for quick removal of methyl orange dye

Cellulose-citric acid-chitosan@metal sulfide nanocomposites: Methyl orange dye removal and antibacterial activity

In this study, to develop efficient adsorbents in removing water pollution, new cellulose-citric acid-chitosan@metal sulfide nanocomposites (CL-CA-CS@NiS and CL-CA-CS@CuS) were synthesized by one-pot reaction at mild conditions and characterized using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM), Energy Dispersive X-ray (EDX) and Brunauer-Emmett-Teller (BET) isotherm. The results of characterization techniques confirm that the desired compounds have been successfully synthesized. The as-prepared composites were applied for the removal of methyl orange (MO) dye from aqueous solutions using a batch technique, and the effect of key factors such as initial pH, shaking time, MO concentration, temperature and adsorbent dose were investigated and discussed. Adsorption results exhibited positive impact of temperature, shaking time and adsorbent dose on the MO removal percent. The MO removal percent has been increased over a wide range of pH from 2 (27.6 %) to 6 (98.8 %). Also, almost being constant over a wide range of MO concentration (10–70 mg/L). The results demonstrated that the maximum removal percentage of MO dye (98.9 % and 93.4 % using CL-CA-CS@NiS and CL-CA-CS@CuS, respectively) was achieved under the conditions of pH 6, shaking time of 120 min, adsorbent dose of 0.02 g, MO concentration of 70 mg/L and temperature of 35 °C. The pseudo-second-order (PSO) and Langmuir models demonstrated the best fit to the kinetic and equilibrium data. Also, the thermodynamic results showed that the MO removal process is endothermic and spontaneous in nature. The MO adsorption can be happened by different electrostatic attraction, n-π and π-π stacking and also hydrogen bonding interaction. In addition, antibacterial activity of CL-CA-CS@NiS and CL-CA-CS@CuS nanocomposites exhibited a superior efficiency against S. aureus.

Radiant synergy: Illuminating methyl orange dye removal with g-C3N4/ZnO heterojunction photocatalyst

In this study, a robust hybrid heterojunction composite of g-C3N4/ZnO was successfully synthesized using a straightforward and cost-effective coprecipitation method. The resulting composite amalgamates the properties of graphitic carbon nitride (g-C3N4) and zinc oxide nanoparticles (ZnO NPs). Thorough characterization using techniques such as XRD, FT-IR, FE-SEM, HR-TEM, UV-DRS, EIS, PL, and EDX confirmed the structural and elemental composition of the catalyst. The challenge of using photons as the sole energy source for the activation of photocatalysts under ambient conditions was addressed. The photocatalytic potential of the hybrid heterojunctions was assessed by degrading the methyl orange (MO) dye under sunlight. The 10 wt% g-C3N4/ZnO composite exhibited effective suppression of charge recombination during photocatalytic degradation. Notably, the heterojunction 10 wt% g-C3N4/ZnO composite displayed remarkable photocatalytic performance, achieving a substantial 98 % degradation of MO within 90 min of solar irradiation, outperforming other materials. Moreover, the synthesized composites exhibited favorable attributes in terms of recyclability and mechanical stability, retaining their efficacy over five cycles. This substantiates their promising role as potential candidates for future photocatalyst applications. In essence, g-C3N4/ZnO heterojunction composites offer a robust solution for efficient and sustainable photocatalytic degradation of organic pollutants.

Removal of methyl orange dye by high surface area biomass activated carbon prepared from bamboo fibers

To obtain a green biomass-activated carbon with abundant pores for the high-efficiency removal of dye, this study fabricated bamboo fiber-based activated carbons (BFACs) via a one-step activation strategy with the assistance of ZnCl2 as the activator for the removal of methyl orange (MO). The results showed that the specific surface area (SSA) of BFAC-500 activated at 500 ℃ was as high as 2512 m2/g with a total pore volume (Vtotal) of 1.411 cm3/g. The adsorption kinetics and thermodynamics of MO conformed to the pseudo-second-order kinetic model and Langmuir isotherm model, respectively. Based on the Langmuir fitting results, the theoretical maximum adsorption capacity (Qm) of MO adsorbed by BFAC-500 was calculated to be 591.71 mg/g at 318 K, pH=4.5, 0.4 g/L, with an equilibrium time of about 60 min. According to the thermodynamic calculation, the value of ΔH0 was less than 40 kJ/mol, which indicates that the adsorption mechanism was mainly based on physical adsorption, and based on the BET, Zeta potential, FTIR, and XPS before and after the adsorption, it was further known that it was mainly characterized by pore filling, electrostatic adsorption, hydrogen bonding, and π-π interactions. Moreover, when pH < pHzpc, the surface of BFAC-500 was positively charged and the adsorption of Cl-, SO42- and PO43- on MO had little effect; when pH>pHzpc, the surface was negatively charged and the adsorption of BFAC-500 on MO was enhanced by Na+, K+, and Mg2+. The BFAC materials in this study have promising applications in the practical removal of MO dyes.

Bacteriogenic synthesis of morphologically diverse silver nanoparticles and their assessment for methyl orange dye removal and antimicrobial activity.

Nanotechnology and nanoparticles have gained massive attention in the scientific community in recent years due to their valuable properties. Among various AgNPs synthesis methods, microbial approaches offer distinct advantages in terms of cost-effectiveness, biocompatibility, and eco-friendliness. In the present research work, investigators have synthesized three different types of silver nanoparticles (AgNPs), namely AgNPs-K, AgNPs-M, and AgNPs-E, by using Klebsiella pneumoniae (MBC34), Micrococcus luteus (MBC23), and Enterobacter aerogenes (MBX6), respectively. The morphological, chemical, and elemental features of the synthesized AgNPs were analyzed by using UV-Vis spectroscopy (UV-Vis), Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and energy-dispersive spectroscopy (EDX). UV-Vis absorbance peaks were obtained at 475, 428, and 503 nm for AgNPs-K, AgNPs-M, and AgNPs-E, respectively. The XRD analysis confirmed the crystalline nature of the synthesized AgNPs, having peaks at 26.2°, 32.1°, and 47.2°. At the same time, the FTIR showed bands at 599, 963, 1,693, 2,299, 2,891, and 3,780 cm-1 for all the types of AgNPs indicating the presence of bacterial biomolecules with the developed AgNPs. The size and morphology of the AgNPs varied from 10 nm to several microns and exhibited spherical to porous sheets-like structures. The percentage of Ag varied from 37.8% (wt.%) to 61.6%, i.e., highest in AgNPs-K and lowest in AgNPs-M. Furthermore, the synthesized AgNPs exhibited potential for environmental remediation, with AgNPs-M exhibiting the highest removal efficiency (19.24% at 120 min) for methyl orange dye in simulated wastewater. Further, all three types of AgNPs were evaluated for the removal of methyl orange dye from the simulated wastewater, where the highest dye removal percentage was 19.24% at 120 min by AgNPs-M. Antibacterial potential of the synthesized AgNPs assessment against both Gram-positive (GPB) Bacillus subtilis (MBC23), B. cereus (MBC24), and Gram-negative bacteria Enterococcus faecalis (MBP13) revealed promising results, with AgNPs-M, exhibiting the largest zone of inhibition (12 mm) against GPB B. megaterium. Such investigation exhibits the potential of the bacteria for the synthesis of AgNPs with diverse morphology and potential applications in environmental remediation and antibacterial therapy-based synthesis of AgNPs.

Synthesis of bimetallic Mn@ZIF–8 nanostructure for the adsorption removal of methyl orange dye from water

In this research, manganese-based Mn@ZIF-8 nanocomposite was prepared using solvothermal strategy. The resultant Mn@ZIF-8 nanostructure was assessed for the adsorption of methyl orange (MO) dye from water. The pristine ZIF-8 and Mn@ZIF-8 nanocomposite have demonstrated a rhombic dodecahedral morphology having a reasonable microporous structure. Besides, they have also displayed an outstanding specific surface area and porosity. The impact of contact time, concentration and variation in pH were analyzed in detail for the investigation of adsorption capacity. From the interpretation of the adsorption isotherms, it has been discovered that adsorption of MO over Mn@ZIF-8 follows the monolayer mechanism (Langmuir isotherm). Remarkable maximum adsorption capacity (qmax, 406 mg.g−1) has been recorded for the Mn@ZIF-8 which is sufficiently high as compared to pristine ZIF-8. The kinetic study explored that experimental data best fitted to the pseudo second order kinetics with relatively high R2 values (0.997) of Mn@ZIF-8. Thermodynamic study reconnoitered the adsorption process is spontaneous in nature. The synthesized Mn@ZIF-8 material also displays exceptional reusability capability of up to 92 % at 4th cycle compared to 1st cycle. Overall, the Mn@ZIF-8 could be a good contestant for the treatment of MO containing wastewater of industries.

Green synthesis of zinc oxide nanoparticles from Salvadora persica leaf extract: Characterization and studying methyl orange removal by adsorption

Abstract The present study conducted a successful green synthesis of zinc oxide nanoparticles (ZnO NPs) from the aqueous solution of Salvadora persica leaf extract as capping agent and used for methyl orange dye removal. The morphology, chemical composition, crystallinity, optical property and isothermal behavior of synthesized nanoparticles were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), Fourier transform infra-red (FTIR), X-ray diffraction (XRD), and UV-visible spectroscopy (UV-Vis). The influencing factors on MO removal such as preparation method, dose, pH, contact time, and dye concentration were examined. The UV-Vis absorption band was found at 365 nm and the XRD analysis confirmed the crystallinity of the ZnO NP and the particle sizes were in the range of 32-68 nm. The FTIR bands confirm the presence of bioactive compounds. SEM images showed the formation of hexagonal and rod-shaped nanoparticles. The results revealed that a maximum methyl orange removal of 68% was obtained with an amount of 0.05 g of ZnO NPs at pH 5. The adsorption process can be well explained by the Langmuir isotherm model. This research demonstrates a green method of preparing various ZnO nanoparticle with a remarkable efficiency towards the removal of methyl orange dye.

Preparation of Ni(II)Fe(III)-layered double oxide and its application for the removal of methyl orange dye: Adsorption isotherm and thermodynamic study

The Ni(II)Fe(III)-LDO has been synthesized by calcination of Ni(II)Fe(III)-LDH at 500 ℃. The prepared LDO is applied in the treatment of Methyl Orange (MO) dye from a synthetic solution. A batch of experiments is conducted to examine the effects of varying adsorption parameters, i.e. initial dye concentrations and temperature. The results indicate that the adsorption of MO increases with rising dye concentration and solution temperature. Temkin, Freundlich, and Langmuir isotherms are analyzed to investigate the adsorption process at different pH levels. Various thermodynamic parameters such as ΔS, ΔH and ΔGº have also been calculated. The adsorption of MO dyes on the Ni(II)Fe(III)-LDO is found endothermic and non-spontaneous in nature. The findings reveal the adsorption process is physical sorption.

Development of novel amino-ethyl chitosan hydrogel for the removal of methyl orange azo dye model

The present study introduces a new and straightforward method for the amination of Chitosan. This method involves coupling Chitosan (CS) with 2-chloroethylamine (ENH2) in a single step to produce an amino-ethyl Chitosan derivatives with increased amine group content (CS-ENH2) using click chemistry. The resulting derivatives were then crosslinked using Glutaraldehyde to form amino-ethyl Chitosan Schiff bases. The novel amino-ethyl Chitosan Schiff bases were subsequently utilized as adsorbents for the removal of Methyl Orange (MO) dye from aqueous solutions using a batch technique, and the performance of the produced Schiff bases was compared with that of the native Chitosan Schiff base. The CS-ENH2 adsorbents show improved adsorption capacity up to 300% of the native Chitosan Schiff base with almost double removal rate. The adsorption temperature has a positive impact in general while almost 100% of MO removed at 60 °C using CS-ENH2 adsorbents compared with 66% of the native Chitosan Schiff base adsorbent. The adsorption pH shows a negative impact on the MO removal percent. That effect reduced sharply using the CS-ENH2 adsorbents with higher amination degree while the MO removal percent almost being constant over a wide range of pH; 2.0–7.0. The agitation speed has the same positive effect over all the adsorbents. However, the rate of MO removal percent decreased with increase the agitation speed up to 250 rpm. The experimental findings demonstrated that the highest percentage of MO dye removal was achieved under the conditions of pH 2.0, a temperature of 60 °C, agitation speed of 250 rpm, and adsorption duration of 90 min. These Schiff bases were subsequently characterized using advanced analytical techniques including Fourier Transform Infrared spectroscopy, Thermal analysis (TGA and DSC), and Scanning Electron Microscopy.

SYNTHESIS OF COPPER NANOPARTICLES USING AMORPHOPHALLUS PAEONIIFOLIUS TUBER EXTRACT AND THEIR PHOTODEGRADATION ACTIVITIES ON METHYL ORANGE DYE

The current study focuses on investigating the removal of methyl orange dye using green-synthesized copper oxide nanoparticles derived from Amorphophallus paeoniifolius tubers. The nanoparticles were characterized using various techniques, including UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). Key parameters for adsorption, such as pH, contact time, adsorbent amount, and initial dye concentration, were examined. Additionally, the energy requirements for the pseudo-first and pseudo-second-order kinetic models were evaluated. This green synthesis method is efficient, cost-effective, and time-saving, leading to the production of copper oxide nanoparticles on a large scale.

Mesoporous biochar derived from Egyptian doum palm (Hyphaene thebaica) shells as low-cost and biodegradable adsorbent for the removal of methyl orange dye: Characterization, kinetic and adsorption mechanism

The present research work reports the preparation of Hyphaene thebaica derived-biochar (HTBC) and its applicability as eco-friendly and low-cost adsorbent for the removal of methyl orange (MO) dye. The main physicochemical characteristics of HTBC including its morphology, crystallinity and chemical function groups were determined through scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The results showed that HTBC adsorbent was found to be constituted by heterogeneous surface with mesoporous having a surface area of 33.38 m2/g and pore diameter of 23.53 nm, and carboxylic and amine functional groups. Adsorption experiments were conducted using batch mode, by varying key adsorption parameters such as contact time, solution pH, adsorbent dosage and concentration. Adsorption isotherm modelling revealed that the Langmuir model (higher R2 and lower χ2) provided a better fit for MO adsorption onto HTBC, while the adsorption kinetics followed a pseudo-second-order kinetic model. Under optimized conditions (pH 2, HTBC dose of 0.03 g, initial dye concentration of 100 mg/L, 313 K, 270 rpm), the maximum Langmuir monolayer adsorption capacity for MO adsorption onto HTBC was found to be 264.922 mg/g. According the thermodynamic parameters, it can be deduced that MO adsorption on HTBC was exothermic and spontaneous. Adsorption mechanism can be attributed to various interactions, including electrostatic attraction, H-bonding, and π-π interaction. In light of these findings, biochar from Hyphaene thebaica shells can be considered a cost-effective and biodegradable adsorbent with significant potential for the treatment of water contaminated with anionic dyes.

Bio-inspired adsorption sheets from waste material for anionic methyl orange dye removal

Nano zero-valent iron (nZVI), bimetallic nano zero-valent iron-copper (Fe0–Cu), and Raw algae (sargassum dentifolium) activated carbon-supported bimetallic nano zero-valent iron-copper (AC-Fe0–Cu) are synthesized and characterized using FT-IR, XRD, and SEM. The maximum removal capacity is demonstrated by bimetallic activated carbon AC-Fe0–Cu, which is estimated at 946.5 mg/g capacity at the condition pH = 7, 30 min contact time under shaking at 120 rpm at ambient temperature, 200 ppm of M.O, and 1 g/l dose of raw algae-Fe0–Cu adsorbent. The elimination capability of the H3PO4 chemical AC-Fe0–Cu adsorbent is 991.96 mg/g under the conditions of pH = 3, 120 min contact time under shaking at 120 rpm at room temperature, 200 ppm of M.O, and 2 g/l doses of H3PO4 chemical AC-Fe0–Cu adsorbent. The Bagasse activated carbon adsorbent sheet achieves a removal capacity of 71.6 mg/g MO dye solution. Kinetic and isothermal models are used to fit the results of time and concentration experiments. The intra-particle model yields the best fit for bimetallic Fe0–Cu, AC-Fe0–Cu, H3PO4 chemical AC-Fe0–Cu and bagasse activated carbon(CH), with corrected R-Squared values of 0.9656, 0.9926, 0.964, and 0.951respectively. The isothermal results emphasize the significance of physisorption and chemisorption in concentration outcomes. Response surface methodology (RSM) and artificial neural networks (ANN) are employed to optimize the removal efficiency. RSM models the efficiency and facilitates numerical optimization, while the ANN model is optimized using the moth search algorithm (MSA) for optimal results.HighlightsThe Fe0–Cu composite, when combined with activated carbon from Bagasse Pulp (CH), exhibited the most effective decolorization effectiveness for anionic colours present in wastewater.The utilization of composites presents a promising opportunity for efficient dye removal due to its cost-effectiveness and environmentally sustainable nature. The utilization of response surface approach and artificial neural network modelling improves the efficacy of removal processes and treatment techniques.

Asymmetric Crosslinked Polyacrylamide/Natural Rubber Semi-IPN Hydrogel for Application of Methyl Orange Dye Removal: Combined Experimental and DFT Study

Asymmetric Crosslinked Polyacrylamide/Natural Rubber Semi-IPN Hydrogel for Application of Methyl Orange Dye Removal: Combined Experimental and DFT Study

Adsorptive removal of methyl orange dye in aqueous solutions using calix[4]arene-modified lead sulphide: insight into response surface methodology, isotherm and kinetic studies

Abstract The present study reports the adsorptive potential of an alternative and regenerative adsorbent, lead sulphide (PbS) modified with calix[4]arene towards a methyl orange (MO) dye solution. The chemical and morphological aspects of synthesised PbS nanoparticles and calix[4]arene-modified PbS were analysed by FESEM, EDX and FTIR, which indicated successful immobilisation of calix[4]arene on the PbS surface. The response surface methodology (RSM), based on central composite design (CCD), was conducted to evaluate the significant factors and to optimise the influence of various factors (adsorbent dosage, contact time and pH) on the adsorption of MO. Under optimal conditions (pH of 4, a dosage of 89.70 mg and a contact time of 129.76 min), the maximum adsorption of MO by calix[4]arene-modified PbS was observed. The MO uptake behaviour was well described by the Freundlich model and the pseudo-second-order kinetic model, indicating a multilayer chemical adsorption with a maximum adsorption capacity (qmax) of 3.268 mg/g. The adsorption mechanism of MO dye on the surface of calix[4]arene-modified PbS can be attributed to various interactions such as dipole–dipole hydrogen bonding interactions, Yoshida hydrogen bonding, π–π interactions and electrostatic interaction. The results strongly demonstrated the use of novel adsorbents, calix[4]arene-modified PbS and a reusability strategy as an alternative adsorbent in MO dye removal.

Adsorption of anionic methyl orange dye by polyaniline, poly(o‐methylaniline) and poly(o‐methoxyaniline)

AbstractThis study reports the effect of substituents in the ortho position of polyaniline on the adsorption capacity to remove the anionic dye methyl orange (MO) from an aqueous solution. The aim of this study is the synthesis of polyaniline (PANI) and its derivatives, poly‐o‐methylaniline (poly‐o‐toluidine, POT) and poly‐o‐methoxyaniline (poly‐o‐anisidine, POA) for the adsorption removal of MO dye. All polymers were obtained by oxidative polymerization of the corresponding monomers and characterized by scanning electron microscopy (SEM) and infrared spectroscopy (IR). The average particle size of the polymer was about 200 nm. The effect of various parameters such as pH, temperature, adsorption time and initial concentration was analyzed. It was found that the adsorption capacity for dye removal increases from 50.68 to 222.56 mg g−1 for PANI, from 16.89 to 66.57 mg g−1 for POT, and from 97.26 to 532.54 mg g−1 for POA with an increase in the initial dye concentration from 5 up to 50 mg L−1. For all polymers, the equilibrium state of MO adsorption was reached in 50 min. The results showed that MO adsorption on PANI, POT, and POA is well described by a pseudo second order kinetic model. Isothermal studies have shown that adsorption is in good agreement with the Langmuir isotherm model, as evidenced by higher values of correlation coefficients. Based on the data of thermodynamic studies, it was concluded that MO adsorption on PANI, POT, and POA is spontaneous and endothermic.

Arthrospira platensis nanoparticle-based approach for efficient removal of methyl orange dye from aqueous solutions: isotherm, kinetic, and thermodynamic analysis

AbstractBlue-green algae Arthrospira platensis, strain NIOF 17/003, is an ecologically friendly were tested as adsorbents for the removal of methyl orange dye (MO) from aqueous solution. The surface deposition of A. platensis was investigated utilizing a variety of techniques, including Fourier-transform infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET), and scanning electron microscopy (SEM). FTIR analysis demonstrated the contribution of carbonyl and carboxylic groups to MO dye adsorption. Different initial concentrations of MO dye (5–30 mg L–1) at contact time (5–180 min.), adsorbent doses (0.05–0.4 g), temperature (20–60 °C), and pH (1–11) were conducted in batch conditions. The results revealed that MO sorption in aqueous solutions increased with contact time and concentration. Temperature also affects MO adsorption. The elimination of MO from the solution augmented as the mass of A. platensis increased. The maximum MO dye sorption onto A. platensis was achieved at 15 mg L−1, 20 °C, 0.4 g, pH 1, for 30 min. A significant quantity of dye can be removed with just 0.1 g of A. platensis, with a removal efficiency of 18.1% and 28.35% for seawater and real wastewater, respectively. Many isotherm equations were used to analyze the experimental results (including Freundlich, Langmuir, Dubinin-Radushkevich, and Temkin models). The maximum adsorption capacity of MO onto A. platensis was 156.25 mg g−1. The fractionary-order kinetic model provided the best fit to experimental data compared with other models. Moreover, the thermodynamic parameters of ΔH° and ΔG° factors showed exothermic as well as spontaneous sorption processes. Additionally, A. platensis can be used more than once for economic gain, and it was found that the percent removal decreased to 89.28% of regeneration after three cycles for synthetic wastewater. These investigations indicate the effectiveness of the blue-green algae A. platensis, which may have significant potential for methyl orange dye applications in wastewater treatment.

ASSESSMENT OF THE EFFICIENCY OF CRUSHED CERAMICS IN ADSORBING METHYL ORANGE DYE FROM WASTEWATER

Objective: This study investigates and assesses the potential of crushed, pulverized ceramics as a low-cost adsorbent for the removal of methyl orange from wastewater. The presence of heavy metals and dyes in water bodies are deadly to the living organisms inside water, in which these pollutants are bio-accumulated and biomagnified in the environment. Due to the health effects of these pollutants, it is, therefore, necessary to treat metal and dye-contaminated wastewater prior to its discharge into the environment in order to comply with the stringent environmental regulations and also safeguard the present and future generations. Methods: The influence of pH, contact time, initial metal concentration, adsorbent dosage and temperature were studied in batch experiments at room temperature and were measured using UV-VIS Spectrophotometer at wavelength 464 nm. Fourier Transform Infrared (FTIR) technique was employed as an instrument for characterization of the adsorbent before and after adsorption and the data were collected and interpreted using Microsoft Excel, 2016. Results: Maximum sorption for methyl orange was found to be at pH 2. The adsorption was rapid at the first 90 min of contact, with uptake of more than 90%, and equilibrium was achieved in 60 min of agitation. Langmuir, Freundlich and BET’s isotherm models were applied to describe the adsorption of methyl orange dye. Fourier Transform Infrared (FTIR) spectra of ceramics powder revealed that OH, C-H, C=C, C-O stretching were responsible for the adsorption. However, the effects of different experimental parameters that influenced the efficiencies of the adsorbent have been evaluated and optimized. Conclusion: The investigation revealed that the adsorption capacity of the powdered ceramics on the removal of methyl orange dye is high enough compared to observed values in literatures. Freundlich’s model fitted the equilibrium data better, while the pseudo-second-order kinetic model was the most fitting from the kinetic data obtained for the adsorption of methyl orange dye.