Dye Solution Research Articles

Adsorptive removal of Congo red dye from industrial effluent using cotton calyx iron oxide (CC-Fe3O4) composite.

Environmental pollution is an emerging issue in the areas of South Asia and the burning of crop residues is one of the major contributors to smog/pollutants production. In recent work, the residues of cotton crop, i.e., cotton calyx (CC), have been converted into a valuable and eco-friendly adsorbent at zero cost for the refining of polluted waters. Furthermore, cotton calyx composite was synthesized with iron oxide (CC-Fe3O4) to improve its sorption potential for the mitigation of selected pollutants, i.e., Congo red (CR) dye. By using FTIR, SEM, TGA, and XRD, the newly synthesized biosorbents were characterized. SEM-EDX and FTIR analyses revealed that both biosorbents (CC and CC-Fe3O4) have a porous surface along with various functional groups, which is an indication of an ideal adsorbent for the sorptive removal of pollutants like dyes. The effect of the operating parameters (dye concentration, adsorbent dosage, temperature, contact time, and pH of the dye solution) on the sorption efficacy was studied to identify optimal conditions. The highest percentage of CR removal (99%) was achieved in an acidic medium using 0.6g CC-Fe3O4 composite in 60min at 20°C. Isothermal modeling of the parameter's optimization data proved that the Langmuir model (R = 0.97-0.99) is more able to explain the sorption process than Freundlich indicates the monolayer sorption process. Adsorption kinetics professed that pseudo-second-order rate law effectively represented the ongoing adsorption system. The thermodynamic studies revealed that the sorption process was spontaneous at room temperature as ∆H° was negative. The maximal sorption capacity among the sorbents is 20.66mgg-1 for CC-Fe3O4 composite, which is higher than CC. In conclusion, CC-Fe3O4 composite proved an efficient biosorbent for the mitigation of CR dye from wastewater.

Screening Refractory Dye Degradation by Different Advanced Oxidation Processes

This study investigated Rhodamine B (RhB) degradation by electro-Fenton (EF), anodic oxidation (AO), and their combination (EF/AO), using a carbon felt cathode coupled to a sub-stoichiometric titanium dioxide Magnéli phase (Ti4O7) anode or a platinized titanium (Ti/Pt) anode. The results indicated that operational parameters influenced the kinetics of electrochemical reactions. An increase in current density from 10 to 50 mA cm−2 significantly enhanced the RhB degradation rate; 30 mA cm−2 was the optimal current density, balancing both energy efficiency and degradation performance. Moreover, higher RhB concentrations required longer treatment. The Microtox® bioluminescence inhibition test revealed a significant toxicity decrease of the dye solution during electrochemical degradation, which was highest with EF/AO. Similarly, total organic carbon removal was highest with EF/AO (90% at pH 3), suggesting more efficient mineralization of RhB and its by-products than with EF or AO. Energy consumption remained relatively stable with all oxidation processes throughout the 480 min electrolysis period. High-resolution mass spectrometry elucidated RhB degradation pathways, highlighting chain oxidation reactions leading to the formation of intermediates and mineralization to CO2 and H2O. This study underscores the potential of EF, AO, and EF/AO as effective methods for RhB mineralization to develop sustainable and environmentally friendly wastewater treatment strategies.

Response surface methodology for the design of malachite green dye removal by γ-Fe2O3 dispersed on reduced graphene oxide sheets

A nanocomposite composed of rGO and γ-Fe2O3 was prepared using ultrasonication for the adsorption of malachite green (MG) dye. The preferential plane diffractions at 2θ values of 35.54° and 26.45° about γ-Fe2O3 (311) and rGO (002) with 19.85 and 20.92 nm crystallite sizes, respectively confirmed the successful formation of nanocomposite nature of the adsorbent. Moreover, XPS and FTIR results also confirmed the composite formation due to the existence of peaks relevant to the composite’s components. The adsorbent’s surface charge (pHPZC = ~ 7.1) was also estimated using the salt addition technique. To minimize experiments and optimize adsorption parameters for the removal of MG by the nanocomposite at 25 °C, central composite design (CCD) using response surface methodology (RSM) was used. The optimal adsorption parameters obtained from the within-range numerical optimization based on 0.923 Derringer’s desirability function were 200 mg/100 mL dose, 80 ppm dye solution, 7.99 pH and 112.68 min. contact time for ~ 90% MG dye removal and 40.64 mg/g adsorption capacity (qm) by rGO/γ-Fe2O3. However, ~ 98% MG dye removal with 64.26 mg/g (qm) was achieved upon extended-range estimation of adsorption parameters. The adsorption data exhibited the best co-relationship with Freundlich isotherm and pseudo-2nd order kinetic model. According to a thermodynamic analysis, the MG adsorption process on the rGO/γ-Fe2O3 surface is exothermic, spontaneous, and less random. Moreover, the thermal stability, desorption, regeneration and reusability of rGO/γ-Fe2O3 nanocomposite were also explored. Finally, this study shows that RSM can be an excellent technique to optimize the dye adsorption process at industrial scale.

Multifunctional properties of cotton fabric tailored via green synthesis of TiO<sub>2</sub>/curcumin composite

In this study, a novel green process was developed to produce a multifunctional cotton (CO) fabric incorporating TiO2/curcumin composites that simultaneously provides UV protection and photocatalytic performance. For this purpose, TiO2 was synthesised using the sol–gel process; loaded with the natural colourant curcumin as a visible light absorber at two temperatures, i.e., 70 and 350 °C; and applied to the CO fabric via the pad–dry–cure process. For comparison, TiO2 was synthesised without curcumin under the same conditions. The synthesis conditions at 70 °C ensured the formation of predominantly amorphous TiO2, while curcumin promoted TiO2 crystallisation despite the low synthesis temperature. A 350 °C synthesis temperature was high enough to form the polymorphic TiO2 anatase phase. Although the increase in synthesis temperature and the presence of curcumin in the composites caused a bathochromic shift in light absorption, the photocatalytic activity of all samples was mainly driven by UV light. Chemically modifying the CO fabric significantly reduced the light transmittance of the samples, with the highest absorption of UV light obtained for the sample containing the TiO2/curcumin composite synthesised at 70 °C. This sample provided excellent UV protection with a UPF value of 51.6. All chemically modified CO samples showed photocatalytic activity, degrading coffee stains and decolourising methylene blue and Rhodamine B dye solutions. The highest photocatalytic efficiency and recyclability were obtained again for the CO sample with the TiO2/curcumin composite synthesised at 70 °C, demonstrating the synergistic effect between TiO2 and curcumin in the composite prepared under these synthesis conditions.

Catalytic-assisted remediation and phytotoxicity evaluations of organic pollutants in the presence of metal-doped Bi2O3-based NPs catalyst.

The chemical co-precipitation method was used to synthesize a variety of pure Bi2O3 and substituted Bi2-2xCoxCdxO3 NPs (x=0.0-0.8) and doping influences were evaluated based on the optical, photocatalytic, morphological, and structural characteristics. Powder X-ray diffraction (PXRD), scanning electron microscope (SEM), Energy dispersive X-ray (EDX), Fourier-transform infrared spectroscopy (FTIR), and UV-visible techniques were used to explore the characteristics of the synthesized Bi2O3-based NPs. XRD measurements confirmed the monoclinic structure and a P21/c space group, whereas the particle size was between 22 and 41nm. The SEM analysis gives the morphology of the synthesized NPs that were diverse and agglomerated platelets, whereas the EDX measurements provide the presence of Co and Cd in Bi2-2xCoxCdxO3 NPs. Additionally, FTIR investigations confirmed the existence of functional groups in Bi2-2xCoxCdxO3 NPs. The ultraviolet-visible absorbance region displaying a considerable red shift allowed for tuning of the band gap from 2.64 to 2.37eV. By analyzing the degradation of Reactive Black 5 (RB-5) dye in the presence of sunlight, pure Bi2O3 NPs showed 65.04% whereas the substituted Bi2-2xCoxCdxO3 NPs demonstrated enhanced photodegradation (86.40%) in 105min. For the degradation of RB-5 dye, the effects of catalyst dosage, dye concentration, and pH variations were studied as well. The phytotoxicity experiment was also performed by comparing the germination of Triticum aestivum seeds in treated and untreated RB-5 dye. In the untreated dye solution, seed germination was 50% inhibited, and in the treated dye solution, germination was observed to be 80%. Additionally, recycling investigations were used to confirm the stability of these fabricated nanoparticles, and the results showed that nanomaterials exhibited significant stability and reusability. Co and Cd-doped Bi2O3 NPs are promising solar-active photocatalysts for dye removal from wastewater applications because of their improved photocatalytic activity and narrow bandgap.

Rapid Dye Loading Techniques in Dye‐Sensitized Solar Cells

AbstractDye‐sensitized solar cells (DSSCs) greatly impacted researchers because of their inexpensive materials (organic/inorganic‐based molecules) and relatively simple fabrication process. The fabrication of DSSCs possesses donor‐acceptor type light‐harvesting materials and simple manufacturing techniques; the technology is the most environmentally friendly. In the process of preparing photoanode, adsorption of dye on the TiO2 is one of the crucial and time‐consuming processes. The conventional method of dye adsorption is carried out by dipping the FTO/TiO2 electrodes in dye solution for 12 to 48 h. In the DSSCs literature, very few techniques were explored to reduce the dye loading time. This review focuses on various dye loading methods, such as electrical adsorption, spray coating, microwave‐assisted ultrasonication, functionalized carboxylate deposition, solution dropping, and electrosorption, and so on. and their consequences in influencing the power conversion efficiency of DSSCs. Dipping and evaporation, solution dropping method, and gas bubbling soaking are inexpensive methods for dye loading. However, the electrochemical methods provide enhanced dye loading within an optimum duration resulting in the improvement of PCE as compared to rest of the methods.

Kinetic and isothermal study of dye absorption using pre-treated natural fabrics using polyamine compounds

The study examined the use of cationic polymers (Polyethyleneimine and chitosan) in treating fabrics like cotton, wool, and cotton/wool (70/30) to improve their dyeability and printability. The study examined factors such as dye concentration, time, and temperature for the dyeing process. Results showed that all dyed and printed fabrics treated with polyethyleneimine and chitosan increased color strength by significant percentages. Fastness properties, such as washing, rubbing, acidic and alkaline perspiration, and lightness, improved significantly. Fabric roughness, tensile strength, and elongation decreased by about 4-10% for each fabric. Additionally, the dyed and printed fabrics showed high resistance to bacteria and fungi. The study contributed to reducing chemicals used in traditional dyeing processes by a significant percentage, as the dyeing bath contained only the treated sample and dye solution. Furthermore kintic and isothermal study was investigated to explain the behaviour of treated fabrics for dye absorption.

Staining Tissues with Basic Blue 7: A New Dual-Polarity Matrix for MALDI Mass Spectrometry Imaging.

Obtaining high-quality matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) images and the reproducibility of the technique depend strongly on the sample preparation protocol. The most crucial part is the application of the MALDI matrix, which often relies on expensive spraying or sublimation coaters. In this work, we present a new dual-polarity matrix for MALDI mass spectrometry imaging (MSI): Basic Blue 7 (BB7), which belongs to the group of triarylmethane dyes. Thanks to its good solubility in water, this matrix allows a quick and simple sample preparation protocol without the need for sophisticated spraying or sublimation instrumentation: dipping the glass with tissue into the dye solution. This technique closely resembles the staining methods employed in classical histopathology. The technique is demonstrated on MSI of lipids in mouse brain sections in positive and negative ion modes using a subatmospheric pressure MALDI source coupled with an orbital trap mass spectrometer. The results are compared with traditional matrices, such as 2,5-dihydroxybenzoic acid (DHB) and 1,5-diaminonaphthalene (DAN). BB7 excels, especially in negative ion mode, offering low background signals and high signal intensities of many lipid classes. Furthermore, the stained tissue can simply be inspected visually and allows basic histopathology annotation prior to MSI. Here, we demonstrate that staining offers excellent image quality, reproducible sample preparation, and the potential for automation and utilization for high spatial resolution MSI.

Fluorometric and colorimetric dual sensor for the quantification of cancer biomarker in complex biological fluid via dissociation of host assisted dye aggregate assembly.

Present study explores the utilization of a host assisted aggregate assembly of a DNA intercalater cationic dye, ethidium bromide (EtBr) with polyanionic macrocyclic host, sulfated cyclodextrin (SCD) as colorimetric and fluorometric dual mode sensor for a cancer biomarker, spermine (Sp). The cationic dye, EtBr at the vicinity of the multi-negative SCD portal experiences strong electrostatic attraction, favoring their aggregation in an end to end fashion. Consequently the solution changes its color from orange to brick red with substantial reduction in the fluorescence intensity. Interestingly, in the presence of multi-cationic Sp, the dye aggregates are dissociated which restores the original color and fluorescence intensity of the dye solution. Such changes in the optical features been calibrated with the added Sp concentration to detect and quantify Sp with an astonishingly low detection limit of 0.28μM in water, 0.59μM in a 1% human serum matrix and 5.9µM in 10% urine matrix. Furthermore, the ability of the system to undergo visible colour change enhances its reliability as a dual sensor, functioning as a fluorometric as well as a colorimetric tool for spermine detection with enhanced sensitivity, selectivity and rapid response.

Synergizing Monte Carlo simulations and experimental insights for efficient cationic dye removal using natural fluorapatite.

Natural fluorapatite (FAP) has been investigated as an adsorbent for the removal of dyes such as methylene blue (MB) and crystal violet (CV) from aqueous solutions. Effective dye removal is crucial for water treatment, particularly for industrial wastewater containing toxic dyes. FAP, a naturally abundant material, was characterized using XRD, FTIR, and SEM analysis. The maximum adsorption efficiency achieved was 97% (23 mg/g) for CV and 95% (13 mg/g) for MB under optimal conditions within an equilibrium time of 50 min. The adsorption capacity increased with the ionic strength of the dye solution, reaching 35 mg/g for CV and 28 mg/g for MB. The kinetic study showed that the adsorption of CV and MB is well described by the pseudo-second-order kinetic model (R2 = 0.999) and fits the Freundlich model significantly, with an R2 = 0.99 for both studied molecules. The thermodynamic analysis (ΔH° = 22.647 and 14.907 kJ.mol-1, ΔS° = 88.627 and 47.330 J.mol-1.K-1 for CV and MB, respectively) revealed that the adsorption process is spontaneous and endothermic, with significant randomness at the adsorbent-adsorbate interface. However, desorption and regeneration tests showed that the efficiency of FAP decreases upon reuse. Despite this, the abundance of natural FAP balances its drawbacks. MD simulations confirmed that adsorption is exothermic and spontaneous, especially in basic conditions, where Van der Waals interactions dominate. These findings suggest that natural FAP has significant potential for dye removal in wastewater treatment applications. The effects of various parameters, including dye concentration, temperature, adsorbent mass, and pH, on the adsorption capacity of FAP were studied. Experimental conditions included an initial dye concentration of 20 mg/L, adsorbent mass of 1 g/L, pH of 12, and temperature of 298 K. The Freundlich model was used to describe the adsorption process, while MD simulations provided insights into the adsorption mechanism.

A Dual Approach to Detecting Iron Ions and Analyzing Water Quality

Abstract This research establishes the foundation for developing an IoT (internet of things)-enabled sensor developed for the rapid and precise detection of Fe ions (Fe+ 3 and Fe+ 2) in drinking water. The investigation incorporates the utilization of Phenol red (PR), Universal indicator (UI), and Eriochrome black T (EBT) dyes, revealing their effectiveness in Fe ion detection. UV-visible tests and calibration graphs determined remarkably low average detection limits and exhibited stability at varying temperatures. Their exceptional sensitivity and selectivity across all Fe ionic states are crucial for continuous monitoring and on-site testing, making them well-suited for practical applications. Moreover, the limit of detection (LOD) of Fe ions in dyes are found to be 0.0189 mM for PR dye, 0.2 mM for UI, and 0.192 mM for EBT dye solution. Validation of the procedure was achieved right through fabrication of a 3D-printed tool. The integration of RGB (Red Green Blue) analysis with the 3D-printed prototype enabled the assessment and detection of iron ions (Fe+ 3 and Fe+ 2), visually represented in a unique RGB chart. This technical progress involves notable implications for Fe detection, demonstrating its ability for using in evaluating environmental and health conditions. Additionally, this novel approach can replace well established sophisticated instruments due to their rapidity and selectivity.

Eco-Friendly Dyeing and Functional Finishing of Organic Cotton Using Optimized Oolong Tea Stems (Agricultural Waste) Through Response Surface Methodology

As people attempt to elude the environmental issues associated with synthetic dyes, interest in natural dyes has recently increased significantly. Oolong tea stems act as a common agricultural waste yet offer advantages like high production, low cost, and a stable supply. The objectives of this research are to investigate the potential utilization of oolong tea waste, specifically tea stems, as a natural dye source for the development of organic cotton fabrics with added health benefits. In this study, using the Kubelka–Munk (K/S) value as an indicator, the dyeing process was refined through response surface methodology (RSM) by investigating the pH of the dye solution, temperature, and duration. Accordingly, it was demonstrated that the optimal effect was achieved at a pH value of 7.9, a duration of 80 min, and a temperature of 90 °C. Furthermore, under these conditions, the color fastness and functional performance of dyed organic cotton were compared with and without chitosan as a mordant. The results showed that the organic cotton dyed with oolong tea stem extract not only had a good color fastness grade but also presented excellent antibacterial properties, ultraviolet protection properties, and oxidation resistance. Especially with the assistance of chitosan, the dyed fabric achieved excellent performance above grade 4 in all color fastness test items; moreover, its antibacterial activity against Staphylococcus aureus reached more than 90%, the ultraviolet protection coefficient reached 25.3, and the antioxidant activity exceeded 90%. Consequently, considering environmental concerns, natural dyes extracted from discarded oolong tea stems are promising substitutes for synthetic dyes in the textile sector.

Pretreatment of granatum dye solution and its application in eco-dyeing of wool

Natural dyes attract attention due to their biodegradability and environmental compatibility. To improve the color depth and color fastness of granatum dyeing of wool fabrics, granatum dyes were pretreated by alkaline agent and the dyeing process was investigated. Granatum dyes were completely dissolved by salt-forming reaction in an alkaline environment, and after adjusting the pH to 3 with acetic acid, the dyes did not precipitate immediately but maintained high solubility during the dyeing process. When the amount of dyes used in the dyeing bath was 5% (o.w.f.), pH of the dye bath was 3, the dyeing temperature was 98 °C, the dyeing time was 90 min, the dyed wool fiber achieved the values of 9.04, 4, and 4–5 for the Integ value, color change and color stain, respectively. This paper presents an easy and effective route to obtain high color depth and good color fastness for wool by polyphenol plant dyes.

Electrospinning Membrane with Polyacrylate Mixed Beta-Cyclodextrin: An Efficient Adsorbent for Cationic Dyes.

A simple and non-chemical binding nanofiber (β-CD/PA) adsorbent was obtained by electrospinning a mixture of β-cyclodextrin (β-CD) and polyacrylate (PA). The cationic dyes in wastewater were removed by the host-guest inclusion complex of the β-cyclodextrin and the electrostatic interaction between the polyacrylate and the dyes groups. The influence of the content of β-cyclodextrin on the surface morphology and adsorption capacity of the nanofiber membrane was discussed, and the optimized adsorption capacity of nanofiber adsorption material was determined. The adsorption capacity of nanofiber adsorbents for basic red 9, basic red 14, basic red 46, basic blue 9, basic yellow 19 and basic yellow 28 was 86.71 mg/g, 21.513 mg/g, 18.926 mg/g, 44.525 mg/g, 116.516 mg/g and 155.206 mg/g, respectively. The effects of different initial concentrations and pH values on the adsorption properties of adsorbent materials were studied. The kinetic analysis showed that the adsorption process of nanofibers for cationic dyes was more in line with the pseudo-second-order kinetic adsorption model. Moreover, nanofiber adsorbent could be easily separated from the dye solution and showed high recycling efficiency. These results indicated that the β-cyclodextrin/polyacrylate composite nanofibers are expected to be recyclable adsorbents in dye wastewater treatment.

Electrospun nanofiber chitosan/polyvinyl alcohol loaded with metal organic framework nanofiber for efficient adsorption and removal of industrial dyes from waste water: Adsorption isotherm, kinetic, thermodynamic, and optimization via Box-Behnken design.

Dyes can seriously harm human health because they linger or break down in the environment and find their way into drinking water through the water cycle. Examples of the most important interactions between MOFs and dyes are provided, and an effort is made to comprehend how surface charge and size compatibility affect the adsorption process. The methods for incorporating functionalized Ce-MOF into electrospun nanofibers made of polyvinyl alcohol and chitosan to create functionalized cerium metal organic framework nanofiber membranes (FCCP nanofiber membranes) are presented in this paper. A number of techniques, including XRD, FT-IR, N2 adsorption/desorption isotherm, SEM mapping, and EDX, were used to successfully manufacture and analyze the adsorbent. Examine the effects of pH, adsorbent dose, starting concentration, contact time, and thermodynamics on the adsorption process of malachite green dye (MG) onto FCCP nanofiber membrane. The Langmuir and pseudo-second-order adsorption processes were fitted. The adsorption process was chemisorption, as shown by the adsorption energy of 31.6kJ/mol. Examine the adsorption mechanism, which may involve electrostatic interaction, pore filling, and π-π interaction. The increase in MG dye absorption at higher temperatures suggests an endothermic and spontaneous adsorption process. For the MG dye solution, the ideal adsorption parameters were determined using the Box-Behnken design software to be pH8, a dosage of 0.2g of FCCP nanofiber membrane per 25mL, and an adsorption capacity of 359.2mg/g. These elements are necessary for the composite sponge to be utilized in water purification processes and to be the most successful at adsorbing arsenate. Applying the Box-Behnken design and response surface approach features of the Design-Expert software successfully enhanced the adsorption process with a small number of planned tests. The stability of the adsorbent was confirmed by an investigation of its reusability using six consecutive cycles of adsorption and desorption, which revealed no appreciable drop in removal effectiveness. It also demonstrated consistent efficiency, preserved homogeneous XRD data, and kept its original chemical composition both before and after reuse.

Single-Injection Composite Tracer Achieves Intraoperative Dual-Tracing and Precise Localization of Sentinel Lymph Nodes.

The use of dual-tracer contrast agents in clinical applications, such as sentinel lymph node (SLN) identification, offers significant advantages including enhanced accuracy, sensitivity, as well as comprehensive and multimodal visualization. In the current clinical practice, SLNs are typically marked prior to surgical resection by multiple and sequential injections of two tracers, the radioactive tracer and methylene blue (MB) dye. This imposes physical and psychological burden on patients and medical staff. Surface-enhanced Raman scattering (SERS) nanotags have emerged as promising SLN tracers due to their high sensitivity and specificity. In this study, we propose a novel single-injection composite tracer consisting of SERS nanotags and MB dye solution, to achieve the accurate intraoperative visualization and localization of SLNs. Laser excitation at the second near-infrared window (1064 nm) minimizes the MB fluorescence background interference, allowing the integration of SERS nanotags with MB solution to form the composite tracer, bridging two distinctive but complementary optical modalities. The feasibility of the composite tracer is demonstrated for SLN navigation on rabbit models. For the first time, we successfully visualize and localize multiple SLNs in the axilla of rhesus monkeys. Our study demonstrates the potential of combining MB with SERS nanotags for SLN navigation as the composite tracer, making a significant advancement toward the SLN biopsy in clinical applications.

Versatile application of fast green FCF as a visible cholangiogram in adult mice to medium-sized mammals

An aqueous solution of a common food dye, Fast Green FCF (FG), mimics cholyl-lysyl-fluorescein to visualize embryonic bile flow via single peritoneal injection into intrauterine mouse embryos. Despite its efficacy in embryos, its suitability for adult mice and small to medium-sized mammals remained uncertain. In this study, we investigated FG cholangiography in adult mice, dogs, and goats. The results demonstrate that FG injection enables progressive cholangiography in these species, highlighting its versatility across different animal models without necessitating specialized equipment. To further evaluate diagnostic utility, FG cholangiography was performed in various mouse models of bile flow disorders. FG successfully visualized dilated lumina in the extrahepatic bile duct of BDL mice and revealed aberrant luminal structures in the gallbladder walls of Sox17+/− or Shh-cre; Sox17flox/− mice. In Mab21l1−/− mice with contracted gallbladders, FG influx was limited to the gallbladder neck. Moreover, stereomicroscopic video analysis of FG influx into the gallbladder post-fasting revealed differences in gallbladder wall state and its bile composition between Sox17+/− and wild-type mice, suggesting the potential for detecting variations in gallbladder stored bile properties. These findings underscore the efficacy of FG in facilitating progressive cholangiography across mammalian species.

Dictyota bartayresiana a sustainable biosorbent for the decolorization of reactive blue 19 – optimization, equilibrium, desorption and toxicological studies

The present study aims to investigate the dye decolorization efficiency of the brown seaweed Dictyota bartayresiana against reactive blue 19 (RB19) dye. The process variables namely dye and biosorbent concentration, pH and incubation time were optimized through BBD based RSM for achieving enhanced dye decolorization. The experimental data well fitted into Freundlich isotherm and proving the heterogenous adsorption of RB19. The Temkin and Dubinin – Radushkevich isotherm models showcased the endothermic and chemisorption mediated adsorption of RB19 onto D. bartayresiana. The pseudo second order kinetic model exhibited the chemisorption assisted adsorption and the Weber Morris kinetic model proved that the intra particle diffusion was not the rate limiting step in the adsorption of RB19 onto D. bartayresiana. Thermodynamic studies revealed the spontaneous, feasible and endothermic process of biosorption. Interaction between the dye and the biosorbent was assessed through UV-Vis, FT-IR and SEM which confirmed the process of decolorization. Desorption and regeneration studies revealed that 73% of the dye was desorbed in the first cycle using 0.1 M NaOH as eluent with regeneration efficiency of 68% which reduced in subsequent cycles highlighting the reusability of the biosorbent. Toxicity assessments of untreated and D. bartayresiana treated RB19 dye solution were examined on the microflora, brine shrimp and fenugreek and the results revealed the nontoxic nature of D. bartayresiana treated RB19 solution. Thus, this study provides valuable insights on utilization of D. bartayresiana as an eco-friendly biosorbent for the decolorization of RB19 and affirms its safe use in various biological applications.

Efficient and sustainable catalytic degradation of methylene blue dye solution by Fe-Si-B amorphous alloy ribbon with large specific surface area

Efficient and sustainable catalytic degradation of methylene blue dye solution by Fe-Si-B amorphous alloy ribbon with large specific surface area

Enhanced photocatalytic dye detoxification by banana peel derived enzyme inherited ZnO/g-C3N4 nanocomposite: Validation by soil health and seed germination analyses

Enhanced photocatalytic dye detoxification by banana peel derived enzyme inherited ZnO/g-C3N4 nanocomposite: Validation by soil health and seed germination analyses