Direct Red Dye Research Articles

Adsorption of Direct Red 23 dye from aqueous solution by means of modified montmorillonite nanoclay as a superadsorbent: Mechanism, kinetic and isotherm studies

A novel adsorbent of modified nanoclay was synthesized by covering of alum on the montmorillonite nanoclay (Al/nanoclay). Al/nanoclay was applied as an efficient superadsorbent to remove Direct Red 23 (DR23) from colored wastewater. The adsorbent was characterized by Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and zeta potential analysis. The effects of various operating parameters, such as contact time, initial dye concentration, adsorbent dose, pH and ionic strength on the performance of adsorption, have been studied. The adsorption experiments showed that pH has an obvious effect on the adsorption efficiency and the highest percentage of DR23 dye removal was observed at pH 2. Zeta potential measurement confirmed that the adsorption mechanism is ascribed to electrostatic interaction between sulfonic groups of the anionic dye and the positive surface charge of the adsorbent. The pseudo-second-order kinetic model and the Langmuir isotherm were found to best describe the DR23 adsorption and the maximum monolayer adsorption capacity at the conditions of pH 2 and the adsorbent dose of 0.05 g/L was 2,500 mg/g. The findings recommend that Al/nanoclay can be successfully used for DR23 dye removal from the colored wastewater.

Degradation mechanism of Direct Red 23 dye by advanced oxidation processes: a comparative study

Textile and dye industries have discharged various kinds of toxic residual dyes particularly azo dyes into the environment. In addition to its resistance to biological degradation, Direct Red 23 (DR-23) azo dye is considered toxic, carcinogenic, teratogenic, and mutagenic to the ecosystem. The aim of this study was to investigate the efficiency of different advanced oxidation processes (AOPs) for DR-23 dye detoxification. Single and combined patterns of AOPs, namely ozonation (O3), O3/ultraviolet (UV), O3/UV/hydrogen peroxide (H2O2), and O3/ultrasonic (US), were applied. The effect of pH (3–11) and initial dye concentration (100-500 mg/L), with implication of UV, H2O2, and US, on dye removal efficiency were studied. Decolorization efficiency was found considerably depends on the initial dye concentration and the pH of the solution. The maximum decolorization was obtained at pH 9. The color removal efficiency reached 100% for 100 mg/L DR-23 dye at 15 min using both O3 and O3/UV processes. The half-life of O3, O3/UV, O3/UV/H2O2, and O3/US were found to be 12.4, 9.0, 15.8, and 10.5 min, respectively. The kinetic of AOPs for DR-23 dye removal followed the pseudo-first-order. For example, the rate constant (k obs) of 400 mg/L dye increased to about 38% using O3/UV as compared to O3 alone. Furthermore, LC-(ESI)-MS/MS analysis of the treated DR-23 dye solution was performed to study the final degradation products. It was shown that a DR-23 dye radical underwent partial and complete decomposition of the dye ring to form final products, namely oxalic acid and formic acid.

Two-stage optimization of Allura direct red dye removal by treated peanut hull waste

In this work, a series of experimental studies on the adsorption of Allura direct red dye (R40) on an as-prepared adsorbent has been carried out. The adsorbent has been produced from the activation of peanut hulls with steam at approximately 850 °C. The current study has gone beyond isotherm modeling; for example, optimization has been carried out to minimize the mass of adsorbent used in order to achieve the most economically feasible setup for industrial applications. Additionally, aside from kinetic modeling, contact time optimization has also been conducted for an adsorption process consisting of a setup using batches of adsorbent with filtration between each stage known as a multistage process such a process can increase efficiency, decrease the amount of adsorbent used, and improve the economic feasibility of the process. It is shown that, with an adsorbent loading rate of 1 g/L, it is possible to achieve 99% removal of the dye if adequate contact time is provided. Depending on the removal percent required, it is possible to reduce the residence time by more than 75% via the optimized multistage batch adsorption process. Thus, the prepared adsorbent is very effective at removing the Allura dye, and as such, can be an environmentally friendly and low-cost adsorbent for wastewater treatment. Novelty statement In the manuscript, for the first time, the adsorbent produced from peanut hull waste is used in sequential batch reactors, and the process is optimized to obtain best wastewater treatment rates while optimizing process time and minimizing adsorbent use

Recovery of iron hydroxides from electro-coagulated sludge for adsorption removals of dye wastewater: Adsorption capacity and adsorbent characteristics

The aims of this research work was to investigate the potentials of raw and calcined iron hydroxides/oxides sludge adsorption for DR28 dye removal. The adsorbent is prepared from electro-coagulated (EC) sludge in industrial wastewater treatment plant, as a Nobel adsorbent for decolorizing direct red 28 dye (DR28). The EC sludge adsorbent were prepared with soaking processes and calcination in a range of temperature. The surface properties of raw and calcined EC sludge adsorbent were examined using Zeta Potential, XRD and FTIR. Basic (effect of solution pH, temperature, initial dye concentration) operation parameters were examined for raw and calcined EC sludge adsorbent. The diffraction patter suggests that the crystalline hematite are produced during calcination and increases its intensity as temperature increases. Langmuir and Freundlich Equation were used to model the adsorption equilibrium; and pseudo first and second order Equation were used to model the adsorption kinetics. The results suggested that the adsorption of DR28 dye is chemisorption, the interaction between the adsorbent surfaces with dye is strong. The Langmuir adsorption capacity of DR28 dye with raw and calcined EC sludge adsorbent was calculated as 1.262 mg/g and 1.252 mg/g respectively with experimental conditions: mixing time=20 min, adsorbent dosage=0.5 grams, initial dye concentration= 20 mg/L and solution pH =2 at ambient temperature. The adsorption kinetics model data were consistent with the pseudo-second-order. The removal efficiency of 97% was recorded at pH 2, ambient temperature 20 mg/l concentration and 1 g/100 ml for 1 hour. High direct red 28 dye uptake capability and cost-effectiveness of sludge utilization from textile wastewater treatment plant make it potentially attractive for dye removal.

A study of the DR23 dye photocatalytic degradation utilizing a magnetic hybrid nanocomposite of MIL-53(Fe)/CoFe2O4: Facile synthesis and kinetic investigations

In this research, cobalt ferrite (CoFe2O4) magnetic nanoparticles as well as MIL-53(Fe) structure were synthesized by the hydrothermal and solvothermal methods, respectively. Moreover, magnetic composites of MIL-53(Fe)/CoFe2O4 nanoparticles with different cobalt ferrite loadings (i.e.; 0.05, 0.1 and 0.2 g) were prepared via the solvothermal method. The main novelty of the present research was to synthesize a magnetic composite of MIL-53(Fe)/CoFe2O4 nanoparticles in order to perform rapid photodegradation of Direct Red 23 (DR23) dye under the LED visible light irradiation. Good magnetic properties of the fabricated composite led to easy separation and rapid retrieval of the catalyst from the reaction mixture. Effects of operational variables such as the initial dye concentration, photocatalyst loading and solution pH upon the performance of synthesized materials were understudied. Characterizations of the prepared photocatalysts were performed through the XRD, SEM, TEM, EDX, FTIR, as well as VSM, DRS, BET-BJH and EIS analyses. Results of the XRD, SEM and FTIR analyses confirmed successful synthesis of CoFe2O4, MIL-53(Fe) and their magnetic composites. Moreover, the desired magnetic value of 28.5 emu/g at 8128 Oe was determined for the MIL-53(Fe)/0.1gCoFe2O4 material. Furthermore, the highest light absorption intensity by this composite was obtained through the UV–Visible DRS analysis. In addition, the value of optical bandgap energy (Eg) for the aforementioned composite was determined to be 2.1 eV. Furthermore, the BET surface areas of the MIL-53(Fe), MIL-53(Fe)/0.1gCoFe2O4 and CoFe2O4 species were evaluated to be 13, 34 and 52 m2/g, respectively. Finally, the photocatalytic degradation of the DR23 over the MIL-53(Fe)/0.1gCoFe2O4 was revealed to be 99.35% after 80 min of duration under the LED irradiations. This was higher than the rest of other understudied materials. In addition, results displayed that, the hydroxyl radicals (OH) as well as photo-generated holes (h+) were the main active species in photocatalytic degradation process undertaken. Ultimately, sufficient yet simple rate law models of the aforementioned dye degradation implementing first- and second-order chemical kinetics upon the prepared catalysts were developed.

Influence of Sodium Sulfate on the Direct Red 28 Degradation by Ozone in a Wastewater Recycling Process: A Stoichiometric and Novel Image Analysis

ABSTRACT The current study presents the treatment of water contaminated with the dye Direct Red 28 in the presence of Na2SO4 at three different concentrations (10, 40 and 80 g/L) by simple ozonation. This wastewater treatment was considered in a wastewater recycling process. At the end of each ozonation cycle, ozonation dynamics, ozone consumption, pH, electrical conductivity and UV/Vis spectra variation were analyzed and correlated with the stoichiometric analysis balance. The efficiency of the wastewater treatment in each reuse cycle was evaluated by a novel image processing method. The image results show that the presence of sulfate improves more than 45% the dye fixation on a cotton sample. However, at high additive concentrations, the color quality decreases 25%, compared with the system with low additive concentration, due to the presence of peroxysulfate ions and the compounds accumulated through the ozonation process.

Structural, Morphological, Optical, Electrical and Agricultural Properties of Solvent/ZnO Nanoparticles in the Photodegradation of DR-23 Dye

Nowadays, in the field of modern technology, application of nanoparticles has an active role in basic and applied sciences. Herein, optimization of the shape and size synthesis of ZnO nanoparticles has been done by using different solvents, namely, isopropyl alcohol (IPA) and triple-deionized water (TDW). The influence of different solvents on the structural, morphological, optical, electrical and thermal properties has been analyzed. The observed morphology was in the form of a ZnO nanosphere with grain size in the range of 20–25 nm. Electrical properties confirmed that the prepared sample can be used for fabrication of charge storage devices with a capacitance range of 7–9 μF. Thermal study revealed that the prepared nanoparticles are useful for application in solar cells. ZnO nanoparticles prepared with TDW (solvent) have better optical properties than IPA, so the photocatalytic properties of synthesized nanoparticles (prepared by TDW) were investigated under ultraviolet (UV) light using direct red-23 (DR-23) dye. Almost complete photodegradation of DR-23 dye was observed within 60 min. Kinetic study reveals the rate constant for photodegradation of DR-23 dye was found to be 0.0613 min−1. This degraded water is further used for agricultural purposes.

Coagulation direct red dye and textile auxiliary agents in the presence of free formaldehyde

Coagulation direct red dye and textile auxiliary agents in the presence of free formaldehyde

Multi-walled carbon nanotubes decorated with Cu(II) triazole Schiff base complex for adsorptive removal of synthetic dyes

This research focuses to prepare a new adsorbent with high adsorption capacity and great selectivity. The synthesized adsorbent was utilized for elimination of dyes from aqueous solution. In order to achieve that hydroxyl functionalized Cu(II) Schiff base named N,N-bis(4 hydroxysalicylidene)-4-H-1,2,4-triazole-3,5-diamine-diaminedicopper(II) has been synthesized and supported on modified MWCNT via covalent bonds. The obtained MWCNT anchored copper complex ([Cu2-L]@MWCNT) has been characterized by different tools including elemental analysis, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmittance electron microscopy (TEM), thermal analysis, UV–Vis spectra and X-ray diffraction which confirmed the loading of bimetallic complex on CNTs. The efficiency of ([Cu2-L]@MWCNT) for the adsorptive removal of Sunset yellow (SY), Direct red 81 (DR-81), and acid blue 92 (AB-92) from aqueous solutions, has been studied under alternative experimental conditions. The experimental data were analysed by the Langmuir and Freundlich isotherm models. The Langmuir adsorption isotherm was perfectly fitted for equilibrium adsorption data. The experimental kinetic of the data were analysed applying pseudo-first-order, pseudo-second-order and Weber-Morris intra-particle kinetic models. The adsorption process follows the second-order kinetics. The adsorption process was confirmed, by thermodynamic studies, to be endothermic and spontaneous. It was found that adsorption capacities followed the order: DR-81 > AB-92 > SY with the values of: 75.70, 58.29 and 26.63 mg/g. Moreover, it has been found that the high adsorptivity observed for direct red dye which has highest molecular weight and contain two azo groups.

Microwave Treated Gardenia Jasminoides Leaves for Adsorptive Removal of Direct Red-28 Dye in Environmental Benign Way

In this work, microwave treated Gardenia jasminoides leaves (MTGL) were employed to remove Direct Red-28 (DR) dye from aqueous medium. Most of DR dye contents removed within 30 minutes at pH 2 and 350 ppm dye concentration by 0.02 mg MTGL. Maximum dye adsorbed by MTGL (88.50 mg/g) was approximately triple than non treated simple Gardenia jasminoides leaves (34.13 mg/g). Adsorption modelling of equilibrium data indicated that removal of DR dye by MTGL followed Langmuir, Freundlich and pseudo-second order kinetic models, having exothermic nature. Desorption studies indicated the reusability of MTGL on larger scale. So it is clear that Gardenia jasminoide leaves can be used on larger scale for anionic dye removal after treatment with formalin in efficient manner.

Silane‐Crosslinked Asymmetric Polythiosemicarbazide Membranes for Organic Solvent Nanofiltration

AbstractCrosslinked polythiosemicarbazide (PTSC) membranes with a positively charged surface are fabricated via a reaction with (3‐glycidyloxypropyl)trimethoxysilane. The integrally asymmetric ultrafiltration membranes discussed here can be easily prepared by water‐induced phase separation using a PTSC solution in dimethylsulfoxide (DMSO). The crosslinked PTSC membranes are stable in DMSO, N,N‐dimethylformamide, and tetrahydrofuran and they reject molecules of molecular weights (MW) above 1300 g mol−1. The influence of the crosslinking agent on the surface charge, membrane solvent resistance, and membrane performance is discussed. The crosslinked asymmetric PTSC membranes totally reject Direct Red dye (MW 1373 g mol−1), while the pristine PTSC membrane does not show any rejection for this dye. This finding suggests that an inorganic‐type‐network is formed during the crosslinking reaction, which tunes the pore size of the prepared membranes.

Synthesis and evaluation of a novel inorganic–organic composite flocculant, consisting of chitosan and poly‐ferric cerium silicate

AbstractBACKGROUNDCoagulation/flocculation is widely used in the treatment of dye wastewater because of the low cost, high efficiency, short process and convenient operation. However, with the increase of pollutants in water and in recent years the higher requirement for environment protection, traditional flocculants have found it difficult to meet the processing requirements. Therefore, to develop new, efficient, stable and environment‐friendly flocculants is very necessary and urgent.RESULTSDecoloration performance and mechanism, stability and structure of flocculants were determined from experimental data, and the results indicated that chitosan and poly‐ferric cerium silicate (CTS‐PFCS) flocculant, a three‐dimensional chain‐net structure with bar‐like branches, was a complex compound rather than a simple mixture of raw materials. The decoloration performance and stability of this flocculant was superior to that of poly‐ferric cerium silicate (PFCS) when treating Direct Red dye wastewater, and also it had a wide range of pH application. The main mechanism for flocculation is charge‐neutralization and chemical adsorption in the initial stage of flocculation and later bridge‐aggregation.CONCLUSIONA novel inorganic–organic composite flocculant CTS‐PFCS was successfully synthesized by the combination of chitosan and homemade PFCS. The potential use of chitosan as an organic additive for modifying inorganic polymers flocculant in the clarification of wastewater was demonstrated. © 2018 Society of Chemical Industry

Novel ZnO–MnO2–Cu2O triple nanocomposite: Facial synthesis, characterization, antibacterial activity and visible light photocatalytic performance for dyes degradation-A comparative study

Novel ZnO–MnO2–Cu2O (ZMC) triple nanocomposite (TNC) was synthesized via the facial synthesis method. For comparison, ZnO–MnO2 (ZM) and ZnO–CuO (ZC) nanocomposites (NCs) were prepared. The prepared samples were characterized by UV–vis, FTIR, XRD, SEM, and EDS techniques. The optical activity of the samples was studied via UV–vis analysis. The FTIR spectra confirmed the presence of metal-O bands in samples. The crystalline structure of the samples was studied via XRD pattern. The morphology of the prepared compounds was analyzed via SEM images. The presence of Zn, Mn, and Cu in the prepared samples was confirmed via EDS test. The photocatalytic activity of ZM NC and ZMC TNC was examined by degradation of Rhodamine B and Direct Red dyes in visible light. In comparison, ZMC TNC degrades dyes considerably faster than ZM NC. The antimicrobial activity of ZMC TNC, ZM NC, and ZC NC displayed a high activity against the common pathogens Escherichia coli (E. coli, ATCC 9637) and Staphylococcus aureus (S. aureus, ATCC 12600) especially in the case of ZMC TNC. As an important achievement, the present researchers showed that the simple synthesis of TNCs is possible, and also TNCs have high capabilities due to their new, consolidated, triple and combined properties.

Degradation of Direct Red-23 Dye by Photolysis with The Addition of C-N-codoped TiO2 Catalyst

Degradation of Direct Red-23 Dye by Photolysis with The Addition of C-N-codoped TiO2 Catalyst

Synthesis of ZnO nanowire and ZnO/CeO2 solid solution nanowire by bio-morphing and its characterization

ZnO nanowire (NW), ZnO/CeO2 solid solution nanowire (SSNW) and composite nanowire (CNW) were resulted by varying the proportions of CeO2, synthesized by bio-morphing. The nano sized cellulosic fibrils present inside the micro fiber bundles of banana (Musa Balbisiana Colla) pseudo stem were used as bio-morphing template. The high aspect ratio of NW imitates the internal morphology of the cellulosic micro fiber bundles (CMFB) used. Raw CMFB and synthesized NWs morphology, composition, crystallinity, band gap energy and functionalities were examined by FESEM, EDX, TEM, XRD, UV–visible DRS and FTIR respectively. The formation mechanism of NW within the natural CMFB also proposed with the help of TG-DTA. Reaction kinetics and mechanism of dye degradation of Direct Red dye (DRD) was investigated under UV and solar light irradiation, the effects of DRD concentration, catalyst dosage and pH were also explored using the synthesized SSNW. The degradation studies substantiated the enhanced photocatalytic degradation under solar light.

Evaluation of magnetic nanoparticles performance as photocatalyst for the catalytic treatment of direct red 28 dye in synthetic and real water effluents

ABSTRACTIntegrated water resources management practice is gaining popularity as an alternative water source due to the limited supply of freshwater. The present study was carried out on the photocatalytic degradation of Direct red 28 (DR-28) dye using magnetic nanoparticles (MNPs; Fe3O4) as a photocatalyst. The study was conducted on the photocatalytic degradation of DR-28 dye in synthetic dye effluent water, to understand the effects of different photoreaction parameters on the degradation kinetics. The influence of different parameters such as time, amount of photocatalyst, concentration of H2O2 and pH was investigated. At the optimum dosage of MNPs (0.6 g/L) with 4 mmol/L of H2O2, significant photocatalytic degradation of DR-28 dye (93.2%) was observed. The kinetic study revealed that the photocatalytic degradation followed pseudo-first-order kinetics. The degradation performance of Fe3O4 nanoparticles as a photocatalyst for DR-28 dye was compared with titanium dioxide (TiO2) and it was found that the performance of Fe3O4 as a photocatalyst is superior to TiO2 photocatalyst. The real dye effluent was also degraded at optimum conditions and promising results were achieved.

Removal of non benzidine direct red dye from aqueous solution by using natural sorbents: beech and silver fir

Removal of non benzidine direct red dye from aqueous solution by using natural sorbents: beech and silver fir

Growth and properties of well-crystalline cerium oxide (CeO2) nanoflakes for environmental and sensor applications

This paper reports the synthesis, characterizations and applications of well-crystalline 2D-cerium oxide (CeO2) nanoflakes prepared by a rapid and facile solution combustion process. The nanoflakes were characterized in detail and applied as photocatalyst for dye-degradation and as an efficient electron mediator to fabricate high-sensitive hydroquinone chemical sensor. The detailed characterizations revealed that the prepared nanoflakes were well-crystalline and grown in very high-density. The synthesized CeO2 nanoflakes exhibited good photocatalytic activity toward the photocatalytic degradation of direct red-23 dye. Further, the synthesized nanoflakes were utilized as an efficient electron mediator to fabricate reproducible and highly sensitive hydroquinone chemical sensor. The fabricated chemical sensor exhibited a reproducible and reliable sensitivity of 2.04μAmM−1cm−2 and the detection limit of 2.914μM with the correlation coefficient (R) of 0.98815 and good linearity from 78μM to 12.5mM. The observed results confirmed that the CeO2 nanoflakes can efficiently be used for photocatalytic and sensing applications.

Ce-doped ZnO nanoparticles for efficient photocatalytic degradation of direct red-23 dye

This paper reports the simple, rapid and high-yield synthesis of Ce-doped ZnO nanoparticles using solution combustion method and its application for photocatalytic degradation. Several concentrations of Ce (0.5%, 1.39%, 2.55%, 3.28%, 3.71% and 4.14%) were doped into ZnO and the prepared nanoparticles were characterized by several techniques in terms of their morphological, structural, compositional, optical and photocatalytic properties. The detailed characterization studies revealed that the prepared Ce-doped ZnO nanoparticles are well-crystalline and possessing good optical properties. Further, the prepared Ce-doped ZnO nanoparticles were used as efficient photocatalyst for the photocatalytic degradation of harmful organic dye, i.e. direct red-23 (DR-23). From the detailed photocatalytic experiments, it was observed that Ce-doped ZnO nanoparticles are exhibiting appreciable photocatalytic activity and the degradation percentage was increased with increasing the concentration of Ce up to 3.28%; however, when the Ce concentration was further increased, the photocatalytic degradation was decreased. Thus, at optimum Ce concentration (3.28%), the prepared Ce-doped ZnO nanoparticles are exhibiting appreciable photocatalytic degradation (~99.5%) only in 70min.

Performance of the light-emitting-diodes in a continuous photoreactor for degradation of Direct Red 23 using UV-LED/S2O82− process

Effectiveness of the UV-Light emitting diodes (UV-LEDs) for degradation of Direct Red 23 (DR23) using an Advanced Oxidation Process (AOP), (UV-LED/S2O82−) in a continuous photoreactor has been investigated in present work. The effects of operational parameters, such as, dye initial concentration, peroxydisulfate concentration, temperature and photonic efficiency were utilized for the decolorization of DR23. The most valuable characteristic of the present work was in using the controllable UV/LEDs as light illumination source, which provide the changing current intensity and examine the effect of irradiation efficiency. The optimum conditions for higher percentage degradation of DR23 dye were obtained with S2O82− (12.5mM), dye concentration (20ppm), 80% of current intensity.