Reactive Blue Dye Research Articles

Efficacy of white rot fungal biomass of Phanerochaete chrysosporium for adsorption and removal of reactive red and reactive blue dyes from water

Water pollution has become a worldwide issue, particularly in developing countries. This study aimed to cleanse water contaminated with reactive red (RR-198) and reactive blue (RB-19) dyes via adsorption onto nonliving white rot fungal biomass Phanerochaete chrysosporium under different operational conditions. It was found that P. chrysosporium removed more of RB-19 than RB-198. The conditions of pH 3, temperature 50 °C, adsorbent dosage 0.6 g, particle sizes of adsorbent (0.25 mm), and contact time (30 min) were optimum for removal of the dyes. RR-198 and RB-19 were removed with levels of 78.4% and 86.4%, respectively at pH 3; 79.6% and 90.0%, respectively using 0.6 g of adsorbent dosage; 82.0% and 87.0%, respectively at 30 min; and 82.0% and 87.2%, respectively at 50 °C. Thus, dead P. chrysosporium biomass was shown to be a biosorbent for the uptake of RB-19 and RR-198 dyes.

Toxicological assessment of reactive blue 19 dye aqueous solutions under UV-LED light

Abstract The dye-contaminated industrial effluent causes serious health issues when it gets mixed with underground water without primary treatment. The current project was designed to treat reactive blue-19 dye aqueous solutions in the presence of hydrogen peroxide (H2O2) and titanium dioxide (TiO2) under UV-LED light. The characterization of the photocatalyst was carried out via X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) for structure, purity, and surface study. The effect of various factors such as pH, TiO2 dose, UV-LED light exposure time, H2O2, and dye concentration, on the degradation rate and cytotoxicity reduction was evaluated and optimized through the Response Surface Methodology (RSM). The maximum degradation of dye solution and chemical oxygen demand (COD) reduction was achieved at 98.81 and 86.22 %, respectively for 50 ppm solution, using UV-LED/H2O2(3 %)/TiO2(6 g/L) hybrid process. The toxicity evaluation through the Allium cepa test demonstrated a 62.40, 65.2, and 56.97 % increase in root length (RL), root count (RC), and mitotic index (MI), respectively, following treatment with the UV-LED/H₂O₂/TiO₂ combined process for 150 min. The hemolytic and brine shrimp tests revealed a reduction in toxicity up to 92.18 and 84.08 %, respectively, after applying the same treatment. Additionally, the Ames test indicated up to 80.94 % reduction in mutagenicity for TA98 and an 84.04 % reduction for TA100 strain when dye samples were treated with UV-LED light in the presence of H₂O₂ and TiO₂ for 150 min. The findings suggested that UV-LED light in conjunction with H2O2 and TiO2 can be a useful tool for the degradation and detoxification of toxic pollutants found in textile wastewater.

Preparation, properties and environment-friendly dyeing application of reactive brilliant blue dye based on triphenodioxazine chromophore

Preparation, properties and environment-friendly dyeing application of reactive brilliant blue dye based on triphenodioxazine chromophore

Adsorption of reactive blue day 49 from aqueous solution on commercial activated carbon and polyaniline electrochemically deposited on carbon felt: Kinetic modeling and equilibrium isotherm analysis

In this study, we investigated the effectiveness of commercially available activated carbon (CAC) and carbon felt (PANI/CF) for the removal of reactive blue dye 49 (RB49) from an aqueous solution. We performed a parametric analytical adsorption research in order to achieve this goal, looking at the impact of several important parameters like the adsorbent mass, the absorption duration, the concentration of ionic strength, and the pH of the RB49 solution. The measurement results demonstrate that the CAC dosage ranged from 0.1 to 5 g. The adsorption levels of RB49 increased from 17.73 % to 97.62 % and the PANI/CF assay from 0.228 to 1.044 g. The percentage of delayed adsorption of RB49 increased from 90.78 % to 99.97 %. It was found that the highest RB49 adsorption was obtained from pH < 7 for both adsorbents. The RB49 adsorption yield increased and then stabilized at equilibrium within 2 hours of contact. The kinetics of RB49 adsorption were determined using pseudo-first-order, pseudo-second-order and Elovich models. According to the experimental results, the pseudo-first order kinetic model proved to be the most suitable for the CAC adsorbent, while the three kinetic models were perfectly suitable for the PANI/CF adsorbent. The adsorption (parameters) isotherms of RB49 were studied using the Langmuir, Freundlich and Temkin models. The experimental data are more satisfactory and better fitted to the Langmuir model for the adsorption of RB49 on CAC and the second adsorbent CF/PANI; the results show that the adsorption studied is in agreement with the three isothermal models. The study shown that the organic dye RB49 may be successfully removed from aqueous solutions using CAC and PANI/CF as adsorbent materials.

Degradation of reactive blue dye under UV irradation using iron based nanocomposites

Abstract The textile industry contributes significantly to environmental pollution through the discharge of non-biodegradable colored dye effluents, emphasizing the need for effective wastewater treatment methods. Traditional approaches, including physical and biological treatments, face limitations, necessitating exploration into advanced oxidation processes (AOPs). Iron-based photocatalysts, particularly those synthesized through green methods, have shown promise in degrading organic pollutants. In this study, iron nanocomposites, including CSINCs, ASINCs, and ACINCs, are synthesized by mixing two different plant extract mixtures with an Iron precursor solution. XRD analysis confirms cubic structures for the prepared nanocomposites, with crystalline sizes of 14.21, 15.79, and 28.74 nm, respectively. UV–vis spectrophotometer shows characteristic absorption peaks in the 380–400 nm range. FESEM imaging reveals spherical particles, and EDX analysis detects typical signals of Fe, O, and C. FTIR spectra indicate various functional groups present in the nanocomposites. The study further focuses on optimizing the degradation of Reactive Blue 171 (RB 171) dye, considering factors such as pH, concentration of RB 171, and photocatalyst concentration. The results demonstrate that ACINCs, specifically at a concentration of 10 mg/100 mL in a mixture with Reactive Blue dye at a concentration of 50 ppm, exhibit enhanced degradation under UV irradiation. This detailed investigation contributes to the understanding of the structural and functional characteristics of Iron nanocomposites and their potential application in the efficient degradation of textile dyes, emphasizing the importance of optimizing key parameters for enhanced photocatalytic performance.

A Novel Coal-Associated Soil as an Effective Adsorbent for Reactive Blue Dye Removal

The project aims to remove reactive blue dye from the effluent of textile industries by utilizing coal-associated soil as an adsorbent, as it possesses effective physical properties and distinguishing characteristics. In comparison to other separation techniques, the adsorption method is the most effective, cost-effective, and straightforward. A batch adsorption investigation was carried out to examine the various adsorption-influencing factors, including solution pH, adsorbent dosage, contact time, temperature, and dye concentration. Contact time of 30 min, an adsorbent dosage of 10g.100 mL-1, a solution pH of 7, a temperature of 30°C, and an initial dye concentration of 100 mg.L-1 were found to be optimal for dye adsorption. Using two distinct kinetic models, the evaluation of kinetic studies revealed that the pseudo-second-order provided the greatest fit, with a higher R2 value than the pseudo-first-order. The thermodynamic parameters Gibbs free energy (ΔG°), entropy (ΔS°), and enthalpy (ΔH°) indicated that the current adsorption system was exothermic and spontaneous. Further study of the adsorption isotherm revealed that the Langmuir isotherm model provided the best fit, with an R2 value of 0.977%.

Zygnema sp. as creator of copper oxide nanoparticles and their application in controlling of microbial growth and photo-catalytic degradation of dyes

Recently, focus has been placed on renewable sources, as they can be provided in large quantities at the lowest possible cost, in order to create nanoparticles. One of these sources is Zygnema moss which used in the present investigation to create Copper oxide nanoparticles (CuONPs). Several phenols and flavonoids were identified the extract of Zygnema sp. via analysis of High performance liquid chromatography. These constituents served as reducing and stabilizing agents for CuONPs. Characterization of CuONPs was performed via UV-visible spectrum that demonstrated peak at 252 nm, Transmission electron microscopy that showed spherical CuONPs with mean diameter of 30.06 nm, Fourier transform infrared spectroscopy that confirm that presence of several functional groups aided to formation of CuONPs. The crystallographic pattern of CuONPs was recorded via X-ray diffraction analysis. Antimicrobial potential of CuONPs was compared to copper acetate and antibiotic/antifungal drug. CuONPs exhibited more inhibition zones against S. aureus (32 ± 0.1 mm), E. coli (36 ± 0.1 mm), S. typhi (27 ± 0.2 mm), E. faecalis (37 ± 0.1 mm), C. albicans (34 ± 0.3 mm) than copper acetate and antibiotic/antifungal drug. Promising MIC values of were recorded against S. aureus, E. coli, and S. typhi. CuONPs at 200 ppm inhibited the growth of C. lunata, F. oxysporium, A. flavus, and Mucor circinelloid with inhibtion of 76.92, 73.33, 63.63, and 53.84%, respectively regarded the control 100% growth. The photocatalytic role of CuONPs was recorded for degradation of reactive red (RR195) and reactive blue (RB) dyes with maximum degradation of 84.66% and 90.82%, respectively at 75 min. Moreover, the optimal dyes degradation was 84.66 and 90.82%, respectively at 40 °C.

Synthesis and photocatalytic properties of zinc-copper bimetallic oxide nanoparticles for removal of reactive blue 19 dye in aqueous suspension

ABSTRACT This research investigates the photocatalytic removal of reactive blue 19 (RB19) dye utilising Zn-Cu (zinc-copper) bimetallic oxide nanocatalysts under UV irradiation. The nanocatalysts were prepared via the co-precipitation technique and thoroughly characterised using different procedures including XRD, FTIR, BET-BJH, FESEM, TEM, and EDX. BET-BJH analysis revealed a specific surface area of 59.774 m2/g for the Zn-Cu bimetallic oxide nanocatalyst. Response surface methodology (RSM) was employed to optimise operational factors such as catalyst amount, pH, H2O2 amount, and UV power, with a quadratic model showing high reliability (R2 = 0.89). Under optimal conditions (4 mg catalyst amount, pH 6.68, 0.42 mL H2O2 dose, 23 W UV power, and 45 min reaction time), the maximum RB19 removal reached 77.14%, increasing to 98.33% after 120 min. The kinetic study revealed a reaction rate constant of 0.884 min−1, indicating efficient removal. Zn-Cu bimetallic oxides demonstrated superior RB19 removal capacity, with only a 5.92% reduction in removal yield after 5 consecutive reuse cycles. This study underscores the potential of Zn-Cu bimetallic oxide nanocatalysts for efficient removal of RB19 dye in suspension media.

Effect of TiO2/Fe2O3 nanopowder synthesis method on visible light photocatalytic degradation of reactive blue dye

Water pollution and scarcity of clean water are major issues of concern globally. In this study, titanium dioxide (TiO2) photocatalyst doped with ferric oxide (Fe2O3) was used to degrade reactive blue dye (171) using sunlight irradiation. Two approaches were employed to synthesize the photocatalyst: synthesis of ferric oxide and titanium precursor through ultrasonic-assisted sol-gel method and using iron (III) nitrate nonahydrate with commercial titanium dioxide. The photocatalysts were characterized using FTIR Spectroscopy, SEM, XRD analyses, and UVDRS to determine their chemical composition, morphology, crystallinity, and light absorption, respectively. The effect of contaminant concentration (1–3 ppm), solution pH and photocatalyst type on the degradation efficiency was studied. Doping enabled visible light absorption as confirmed by the UVDRS analysis. Solar photocatalytic degradation resulted in complete (100 % removal) of the dye within 2 h under solar irradiation for all concentrations of the dye studied. Furthermore, the photocatalysts exhibited superior performance in both neutral and acidic solutions compared to basic ones. After four cycles, the dye removal efficiency has decreased by less than 15 % for all the photocatalysts confirming the significant activity and high stability of the nanocomposite. The increased dye photodegradation efficacy of Fe2O3 doped TiO2 under sunlight irradiation is attributed to the narrowing of the photocatalyst's bandgap from 3.76 eV (in pure TiO2) to 2.83 eV. This narrowing of the bandgap enhances the absorption of visible light from sunlight, thus making this photocatalyst effective under sunlight and eliminating the use of electricity which is a requirement for ultraviolet photocatalysis.

Physicochemical Characteristics and Dyeing Properties of Novel Cellulosic Fibers Derived from Sustainable Agricultural Waste

Development of new innovative sustainable fibres from agricultural waste are in great demand these days. For the expansion of these fibres at commercial level, understanding about physicochemical properties of these fibres and specifically their dyeing behavior is essential. In this consequence, in the present study, a natural lignin-cellulosic fibers were extracted by a simplistic route, from lotus silk. The fibers were turn in to yarn by hand twisting and then natural as well as chemical dyeing was performed by the standard dyeing method established for cotton dyeing. Natural henna dye, C.I Reactive blue and indigo dye was used in the present study. Physico chemical properties and dyeing mechanism of the prepared fibers were studied and analyzed in detail in comparison with cotton cellulosic fibres. The lotus fibers were described for their organic construction and morphology by FT-IR spectroscopy and Scanning Electronic Microscopy respectively. Tensile strength, moisture regain and elongation percentage at break were also evaluated. The outcomes revealed that lotus fibers are cellulosic in nature same as cotton but with higher moisture absorption and lower crystallinity as compared to cotton fibers. Lotus fibers revealed higher color strength and color co-ordinates when compared to cotton fibers dyeing. Hollow and irregular fiber surface of lotus fibers along with higher moisture absorption and low crystallinity are the major reasons for higher chemical reactivity and absorption of dyes. The tensile strength and elongation observed in lotus fibers are suitable to be used these fibers in textile products. Lotus fibres from the agricultural waste can be a new source of sustainable textile products for future applications.

High removal performance of reactive blue 5G dye from industrial dyeing wastewater using biochar in a fixed-bed adsorption system: Approaches and insights based on modeling, isotherms, and thermodynamics study

In an eco-friendly context, an adsorption study was performed in a fixed-bed column system to remove organic pollutants from dyeing wastewater, testing preliminary theoretical models and reactive blue 5G (RB5G) dye as a reference pollutant and tilapia bone-based biochar as an alternative adsorbent. Adsorption approaches in removing RB5G dye molecules from synthetic solutions were performed to understand better based on a reliable mathematical representation and provide insights and strategies into treating dyeing wastewater. Initial dye concentration, pH, temperature, and stirring velocity were used as process variables to search for maximal capacity in batch mode. Thermodynamic analysis and a series of phenomenological kinetic models were applied to understand and interpret the mechanisms and develop a predictive model for a fixed-bed column adsorption system, trying to minimize the total organic carbon (TOC) in dyeing wastewater. An intraparticle mass transfer resistance model and the Langmuir-BET isotherm better represented kinetic and equilibrium data, respectively. In the Langmuir-BET model context, the first monolayer has systematically changed its predicted Langmuir adsorption capacity from 18 mg g−1 to 31 mg g−1 being favored by the increase in temperature of 30 to 60 °C, respectively, with the lowest Gibbs free energies for the multilayer formation ruled by weak physical interaction. Theoretical values of the breakpoint, full saturation time, and useful column height were well predicted related to their experimental ones, including the better fitting of all adsorption curve patterns in a fixed-bed adsorption column system with an adsorption capacity of 30.4 mg g−1 (at 50 °C) for an inlet of 200 mg L−1 RB5G solution resembling almost the same value found in batch mode (30.9 mg g−1). After treating the dyeing wastewater characterized by 75 mg L−1 RB5G dye, the adsorption capacity of 23.3 mg g−1 was attained with a 12% loss in comparison with the expected one for a synthetic RB5G solution due to adsorptive competition with other organic pollutants. Finally, a final TOC value near 5.0 mg L−1, the maximum allowed for the Brazilian environmental council, was attained with an almost zero RB5G concentration after a 5-h breakpoint.

Synthesis of Polymeric Sunscreen Photocatalyst ZnO2, CuO2, PbO2, and CdO2 Using Ethylene Glycol for Reactive Blue Dye Removal from Textile Waste Water

Synthesis of Polymeric Sunscreen Photocatalyst ZnO2, CuO2, PbO2, and CdO2 Using Ethylene Glycol for Reactive Blue Dye Removal from Textile Waste Water

Biosorption of Toxic Reactive Blue Textile Dye from Effluent Water Using Immobilized Biomass Based Adsorbent

The present research employed immobilized Canna indica beads (CIBs) to obtain maximum degradation of highly toxic Reactive Blue Dye (RBD), predominantly used in textile industry. The CIBs were characterized using FTIR and SEM-EDX analysis. A batch adsorption study was conducted to measure the removal of harmful RBD dye. Different factors were examined in the biosorption technique to achieve the maximum level of toxic dye elimination, such as adsorbent-solute interaction time (5-120 min), solution pH (2-10), adsorbent dose (25 to 250 mg/100 mL), RBD concentration (50-250 mg/L), and temperature (30-60°C). Removal of 99.96% of RBD was successfully achieved at the optimum pH 7, RBD concentration of 50 mg/L, adsorbent dosage of 150 mg/100 mL, a temperature of 303 K, and 60 min of interaction time. The Langmuir isotherm and pseudo-second-order (PSO) kinetic model data have been found to be an ideal match compared to the Freundlich isotherm and pseudo-first-order (PFO) kinetic model. The maximum adsorption capacity onto CIBs biosorbent was found to be 70.49 mg/g. It was noticed that the chemical reaction occurred naturally and released heat during the process which denoted an exothermic reaction. These results shown that the adsorption of RBD removal is efficient using prepared adsorbent from Canna indica root tubers. Therefore, these CIBs could be used for other toxic dyes and heavy metals from industrial wastewater.

Biosorption of Toxic Reactive Blue Textile Dye from Effluent Water Using Immobilized Biomass Based Adsorbent

The present research employed immobilized Canna indica beads (CIBs) to obtain maximum degradation of highly toxic Reactive Blue Dye (RBD), predominantly used in textile industry. The CIBs were characterized using FTIR and SEM-EDX analysis. A batch adsorption study was conducted to measure the removal of harmful RBD dye. Different factors were examined in the biosorption technique to achieve the maximum level of toxic dye elimination, such as adsorbent-solute interaction time (5-120 min), solution pH (2-10), adsorbent dose (25 to 250 mg/100 mL), RBD concentration (50-250 mg/L), and temperature (30-60°C). Removal of 99.96% of RBD was successfully achieved at the optimum pH 7, RBD concentration of 50 mg/L, adsorbent dosage of 150 mg/100 mL, a temperature of 303 K, and 60 min of interaction time. The Langmuir isotherm and pseudo-second-order (PSO) kinetic model data have been found to be an ideal match compared to the Freundlich isotherm and pseudo-first-order (PFO) kinetic model. The maximum adsorption capacity onto CIBs biosorbent was found to be 70.49 mg/g. It was noticed that the chemical reaction occurred naturally and released heat during the process which denoted an exothermic reaction. These results shown that the adsorption of RBD removal is efficient using prepared adsorbent from Canna indica root tubers. Therefore, these CIBs could be used for other toxic dyes and heavy metals from industrial wastewater.

Polymeric ferrite composites as versatile adsorbents for enhanced reactive blue dye removal: a promising solution for treating textile wastewater

ABSTRACT Water contamination caused by the increasing industry and urbanisation is one of the most significant environmental problems that entire planet is facing. Various polymeric ferrite composites synthesised in the current study were employed to remove the synthetic reactive dye blue-248 from wastewater. The polymeric ferrite composites were characterised using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transmission infrared spectroscopy (FTIR) to observe the surface morphology, crystallinity and chemical structure of as-prepared composites. The optimum removal of dye using Ni-CoFe2O4/Chitosan, Zn-NiFe2O4/Starch, CoNiZnFe2O4/Polyaniline, Ni doped CrZnFe2O4/Alginate, Cr doped ZnCoFe2O4/PVA was at (i) pH 2 (32.34 mg/g), 3 (30.31 mgg−1), 3 (21.05 mgg−1), 3 (25.69 mgg−1) and 4 (38.61 mgg−1), (ii) optimum dose (0.03 mg/g) 32.40, 30.27, 21.91, 25.98 and 39.2 mg/g, (iii) Contact time (6090 min) 46.898, 37.70, 43.318, 29.356 and 34.12 mg/g, (iv) Initial dye concentration 32.24 mgg1, 25.79 mgg−1 (120 mg/L), 35.85 mgg−1, 28.37 mgg−1 and 40.37 mgg−1 (150 mg/L) and (v) temperature (65°C) 29.67, 27.08, 21.66, 23.60 and 41.40 mg/g, respectively. Different equilibrium, kinetic and thermodynamic models were used to check the nature of sorption, reaction rate/order of reaction and feasibility of reaction, respectively. The effect of presence of various electrolytes, different metals and surfactants in wastewater were also studied. For dye removal on a large scale, the effects of bed height (1–3 cm), flow rate (1.8–5.4) and initial dye concentration (50–90 ppm) were examined in column study. Different eluents were used for the desorption study of reactive dyes to check the reusability of process.

Ceramic adsorbent material in removing reactive blue bf 5G dye from synthetic wastewater

This work evaluated the removal of the reactive blue BF 5G dye in Ceramic Adsorbent Material (CAM) prepared from Water Treatment Sludge (WTS). The CAM disks were treated at 480 °C. The materials were characterized regarding pH, electrical conductivity, moisture, solid and granulometric fraction, TGA, DSC, XRF, XDR, FTIR, SEM, BET and pH-PZC. The characterization reveals that CAM presented chemical and mineralogical composition promising for adsorption, with negative zeta potential, and a microporous and rough surface. Besides, the CAM has proven safe to produce and apply according to solubilization tests. The adsorption efficiency was evaluated regarding the effect of the pH, concentration of dye, number of CAM disks, and contact time. The best performance was achieved at pH3, with efficiency higher than 80 % after 48 h of treatment using 1 CAM disk and dye concentration between 1 and 30 mg·L−1. The equilibrium time varied between 24 h and 48 h according to the dye concentration. Kinetic, isotherm, and thermodynamic analyses showed that dye is spontaneously retained in the CAM by monolayer physisorption. This work shows that CAM can effectively remove the reactive blue BF 5G dye until the absence of color, which allows its correct disposal in the environment. Thus, this manuscript presents the preparation and application of a novel material, obtained from WTS, with potential to treat textile wastewater.

Low-cost magnetic carbons-based rubber seed husks materials for highly efficient removal for reactive black 5 and reactive blue 19 textile dyes from wastewater

ABSTRACT Suitable and cost-effective magnetic carbons (CA-HP-FeII/FeIII) were prepared from biobased rubber seed hull materials by chemical activation with phosphoric acid and ferric ions. Physical and chemical properties of the materials were investigated using XRD, FT-IR spectroscopy, SEM analysis, N2 adsorption/desorption, Raman analysis and EDX/EDX-mapping. Magnetic carbons were used to remove reactive black 5 and reactive blue 19 textile dyes in aqueous solution. The pH of the solution, the mass of magnetic carbons and the initial concentration of dyes were investigated. The activated carbon obtained has a surface area of 110 m2.g−1 with an amorphous structure. A maximum removal efficiency of 76.27% for reactive black dye 5 and 94.44% for reactive blue dye 19 was achieved, at optimum pH 2. Kinetic studies showed that non-linear Elovich’s model accurately describes the adsorption mechanism, which assumes an energetically heterogeneous magnetic carbon surface. The two-parameter non-linear models for the adsorption isotherms revealed that the adsorption of reactive black 5 and reactive blue 19 on CA-HP-FeII/FeIII satisfied the Temkin isotherm, demonstrating the exothermic nature of the adsorption process. The three-parameter adsorption isotherm reveals that the magnetic carbons have a heterogeneous surface with energetically diverse adsorption sites. Magnetic carbons were found to be attractive and suitable for the purification of these dyes.

An experimental investigation of textile dyeing wastewater using modified electro Fenton process with optimization by response surface methodology

AbstractElectro‐Fenton oxidation may improve wastewater biocompatibility. In this investigation, steel flakes were used as a novel catalyst in the Enhanced Electro Fenton procedure, in place of the traditional Electro Fenton Process. A degradation study of textile dyeing effluent has been conducted using the Modified Electro Fenton process. In 60 min of reaction time in the Electro‐Fenton process, 98.57%, 95.38%, and 94.93% of color removal was achieved for reactive blue, reactive yellow, and reactive black dyes respectively. From the Laboratory‐scale feasibility studies on the Electro‐Fenton process, the utmost color and COD elimination efficiency of 93% and 70% correspondingly observed at a catalyst dosage of 1 g/L, H2O2 dosage of 132 mM at pH 3. In this study, the average coefficient of correlation was 0.9978, indicating that the framework could describe 99.78% of the variability in response. The Analysis of variance (ANOVA) of the quadratic regression analysis shows that the model is incredibly substantial, as displayed by the Fisher F‐test (F model = 347.52) with the lowest probability value (p model &gt; F = 0.0001). The predicted results from Response Surface Methodology (RSM) closely agreed with the experimental results obtained during the optimization studies and hence confirmed the results obtained.

Enhanced photocatalytic performance of milkvetch-derived biochar via ZnO–Ce nanoparticle decoration for reactive blue 19 dye removal

In this research, the photocatalytic removal of reactive blue 19 (RB19) dye is investigated employing zinc oxide/cerium (ZnO@Ce) nanoparticles decorated with biochar under LED irradiation. Synthesis of ZnO@Ce nanoparticles decorated with biochar was performed utilizing the co-precipitation procedure and, then, the texture and morphology of the fabricated nanocomposite were analyzed using energy dispersive X-ray (EDX), field emission scanning electron microscopy (FE-SEM), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), and Fourier transform infrared (FTIR) spectroscopy techniques. Moreover, FE-SEM images demonstrate that ZnO–Ce nanoparticles were successfully decorated on the surface of biochar. The specific surface areas of biochar and biochar/ZnO–Ce were 519.75 and 636.52 m2/g, respectively. To achieve the maximum yield in the removal of RB19 dye, the effects of operating variables including dye concentration, LED lamp power, biochar@ZnO–Ce catalyst dose, pH and H2O2 dose were explored. Besides, the maximum percentage of RB19 dye removal was 96.47% under optimal conditions, i.e. catalyst dosage of 100 mg, H2O2 dosage of 1 mL, pH of 9, initial dye concentration of 5 ppm, LED power of 50 W, and reaction time of 140 min. Furthermore, the kinetic analysis reveals that the removal of RB19 dye follows the pseudo-first order kinetic model, with calculated values of a reaction rate constant of 0.045 min−1 and a correlation coefficient of R2 = 0.99, respectively. Moreover, the reusability and recyclability of biochar@ZnO/Ce nanocatalyst was promising over five runs, with only a 6.08% decrease in RB19 dye removal efficiency. Therefore, it can be concluded that the biochar @ZnO/Ce photocatalyst can be promisingly applied for the removal of azo dyes in aqueous solutions.

Spectroscopic, mineralogical and photocatalytic characterization of bentonite clay: A jointed DFT and experimental approach

Over the years, the research and development of different systems based on clay minerals as raw materials stand out due to their eco-friendly behavior, abundant world reserves, low cost, and high industry suitability. Although bentonite clays have been largely studied, the literature still lacks a careful mineralogical and spectroscopic characterization. In this work, sodium bentonite clay mineral found in Argentina was carefully characterized from different spectroscopic techniques and had their mineralogical properties evaluated. Photocatalytic studies aiming at the degradation of reactive blue dye and DFT quantum calculations were also performed. The results indicate the existence of cluster particles with irregular sizes and lamellae stacking typically found in montmorillonite clay minerals. It was also observed high amounts of SiO2 and Al2O3 as well as the presence of Al atoms within the tetrahedral sheet evidencing isomorphic substitutions of Si. The properties evaluation showed increased swelling and exchange cation capacities allied to a typical semiconductor band gap. The degradation essays performed indicate a decoloration efficiency of 40 % in the presence of H2O2. In addition, the theoretical investigation provides valuable insights into the influence of impurities and defects on the structural and electronic properties of bentonite mineral clays.