Removal Of Safranin Research Articles

Safranin removal by fine soil: thermodynamics and kinetics of adsorption

AbstractEnvironmental problems caused by human intervention in nature are some of the most critical challenges facing human societies. It is essential to use suitable adsorbents to remove pollutants. The abundance, natural abundance and low cost of fine soil have made it a good candidate for removing environmental pollutants. In this research, removal of safranin dye by natural and acidic-organic-treated fine soil with sulfuric acid and ethanolamine was studied. The characteristics of natural and acidic-organic-treated fine soil were confirmed using X-ray diffraction, Fourier-transform infrared spectroscopy, Brunauer–Emmett–Teller and scanning electron microscopy techniques. The adsorbents were placed in contact with different concentrations of safranin dye solution separately. After that, the effects of adsorbent amount (0.4–3.2 g L−1), contact time (0–60 min), adsorbate concentration (5–20 ppm) and pH (3–11) were evaluated regarding the optimum safranin adsorption process. The greatest adsorption capacity of fine soil was calculated as 1250 mg g–1. The experimental results were evaluated using thermodynamic and kinetic models. The data showed that the process follows the Langmuir isotherm model and pseudo-second-order kinetic model. The intraparticle diffusion model estimated the possible mechanism of dye adsorption. Overall, it can be deduced that natural fine soil is an efficient remover of human pollutants.

Efficient and Inexpensive Bio Adsorbent for the Removal of Safranine: Kinetic and Isotherm Study

Efficient and Inexpensive Bio Adsorbent for the Removal of Safranine: Kinetic and Isotherm Study

Synthesis of novel bentonite/pectin-grafted-poly(crotonic acid-co-acrylic acid) hydrogel nanocomposite for adsorptive removal of safranin O dye from aqueous solution

ABSTRACT This novel work is devoted to the synthesis of the bentonite/pectin-grafted-poly(crotonic acid-co-acrylic acid (AA-co-CA) hydrogel nanocomposite by free-radical copolymerisation method for exploring its potential towards safranin O dye removal. The prepared nanocomposite was characterised by different techniques revealing the presence of numerous functionalities, porous nature and greater swelling % at basic pH. The pHpzc of the nanocomposite was determined to be 4. Maximum of 97.09% of safranin O dye removal take place under optimised conditions, that is, 0.03 g of bentonite dose (bentonite to net hydrogel weight ratio (1.295%), with pH of 7, nanocomposite dose of 5 g/l for 120 min. The dye concentration was 500 mg/l at the temperature of 25°C. Effect of ionic strength confirmed the greatest decrease in adsorption capacity in the presence of divalent cations. The highest R2 and the lowest error margins of the Freundlich isotherm and pseudo-second-order kinetic models make these models well fitted to the experimental data. Further, the spontaneous and exothermic nature of the process was confirmed by the negative values of ΔG and ΔH, respectively. The enhanced adsorption of safranin O dye by the prepared nanocomposite was informed by several mechanisms, including electrostatic, pore filling and H-bonding. A comparison of the adsorption capacity of the prepared nanocomposite with various other adsorbents was also studied. Stability of the prepared adsorbent was revealed from its recovery upto five cycles in different desorption media. Finally, the treatment of the adsorbent with real textile wastewater showed its removal efficiency as 95.8% highlighting its promising nature for treating large industrial wastewater.

PHOTOCATALYTIC DEGRADATION OF SAFRANIN O DYE UNDER VISIBLE LIGHT USING NiO-MgO CATALYSTS

In this study, NiO-MgO catalysts were used as photocatalysts for the degradation of Safranin O (SO) dye as a textile pollutant model from water. NiO-MgO was prepared by the self-combustion method. Characterization was performed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The photocatalytic activity of the prepared NiO-MgO catalyst was evaluated by experiments involving irradiating the Safranin O (SO) dye aqueous solution containing the prepared material with visible light. The percent photodegradation was determined spectrophotometrically by monitoring the maximum wavelength (λmax) of Safranin O (SO) at 518 nm at different irradiation times. The dye decolorization rate of the NiO-MgO material under visible light was 98.42%. The effective reusability and stability of the prepared catalysts were also evaluated. This efficiency remained almost unchanged after three cycles of use, demonstrating the reusability and applicability of the material’s catalytic activity in the removal of Safranin O from water.

Adsorptive Elimination of a Cationic Dye and a Hg (II)-Containing Antiseptic from Simulated Wastewater Using a Metal Organic Framework.

Several types of pollutants have acute adverse effects on living bodies, and the effective removal of these pollutants remains a challenge. Safranin O (a biological dye) and merbromin (a topical mercury-containing antiseptic) are considered organic pollutants, and there are only a few reports on their removal. Synthesized and well-characterized (through PXRD, FTIR, FESEM, and EDS analysis) MOF-5 was used for the first time in the removal of safranin O and merbromin from simulated wastewater and real wastewater. In both cases, MOF-5 effectively removed contaminants. We found that in simulated wastewater, the highest efficiency of removal of safranin O was 53.27% (for 15 mg/L) at pH 10, and for merbromin, it was 41.49% (for 25 mg/L) at pH 6. In the case of real wastewater containing natural ions (Na+, K+, F-, Cl-, SO42-, PO43-, Mg2+, and Ca2+) and other molecules, the removal efficiencies of these two dyes decreased (34.00% and 26.28% for safranin O and merbromin, respectively) because of the presence of other ions and molecules. A plausible mechanism for the removal of these pollutants using MOF-5 was proposed.

Facile Synthesis and Characterization of Manganese Ferrite Nanoparticles for the Successful Removal of Safranine T Dye from Aqueous Solutions

Safranine T dye causes health problems such as skin and respiratory irritations. Hence, the safranine T dye was efficiently removed from aqueous media employing a simply synthesized manganese ferrite (MnFe2O4) nanoadsorbent. The synthesis of manganese ferrite nanoparticles was carried out by the pechini sol–gel approach using tartaric acid to serve as a chelating agent in addition to 1,2-propanediol to serve as a crosslinker. The TEM analysis showed that the shape of MnFe2O4 nanoparticles is semi-spherical, with an average particle size of 19.32 nm that coincides well with that measured from the XRD (18.89 nm). Further, the several factors that influenced the removal process of safranine T dye were examined, such as time, dye concentration, pH, and temperature. The ideal experimental conditions that achieved the highest safranine T dye removal percentage are pH 8, 80 min, and 298 K. The maximum adsorption capacity of MnFe2O4 nanoparticles towards safranine T dye equals 334.45 mg/g. The removal process of safranine T dye by manganese ferrite nanoparticles was chemical, exothermic, and well defined through the Langmuir equilibrium sorption isotherm in addition to the pseudo-second-order model. The synthesized manganese ferrite nanoparticles have the ability to be reused many times without losing their efficiency.

Synthesis and characterization of nanobiochar from rice husk biochar for the removal of safranin and malachite green from water

Xenobiotic pollution in environment is a potential risk to marine life, and human health. Nanobiotechnology is an advanced and emerging solution for the removal of environmental pollutants. Adsorption-based technologies are being used to alleviate the global prevalence of xenobiotics like dyes, due to their high efficacy and cost effectiveness. Current study explored the potential of nanobiochar syntehsized via ultrasonication and centrifugation from rice husk for dye removal from water. It involves the synthesis of nanobiochar from rice husk biochar for removal of Safranin, Malachite green, and a mixture of both from aqueous water. Biochar was synthesized through pyrolysis at 600 °C for 2 h. To convert it into nanobiochar, sonication and centrifugation techniques were applied. The yield obtained was 27.5% for biochar and 0.9% for nanobiochar. Nanobiochar analysis through Fourier-Transform Spectrometer (FTIR), X-ray Power Diffraction (XRD) and scanning electron microscopy (SEM) suggested its crystalline nature having minerals rich in silicon, with a cracked and disintegrated carbon structure due to high temperature and processing treatments. Removal of dyes by nanobiochar was evaluated by changing different physical parameters i.e., nanobiochar dose, pH, and temperature. Pseudo-first order model and pseudo-second order model were applied to studying the adsorption kinetics mechanism. Kinetics for adsorption of dyes followed the pseudo-second order model suggesting the removal of dyes by process of chemical sorption. High adsorption was found at a higher concentration of nanobiochar, high temperature, and neutral pH. Maximum elimination percentages of safranin, malachite green, and a mixture of dyes were obtained as 91.7%, 87.5%, and 85% respectively. We conclude that nanobiochar could be a solution for dye removal from aqueous media.

Adsorptive removal of Safranine T dye from aqueous solutions using sodium alginate–Festuca arundinacea seeds bio–composite microbeads

In this study, composite microbeads were prepared using Festuca arundinacea seeds and sodium alginate biopolymer at different ratios and utilized as sorbents for the sorption of Safranine T from wastewater. The sorbents were characterized by FTIR, SEM, XRD, and BET analysis. According to BET analysis, the specific surface area of the adsorbents was calculated to be 10.99 m2/g and the surface was found to be mesoporous. The optimum conditions for adsorption studies including initial pH (2−12), concentration (10–50 mg/L), contact time (0–150 min), and adsorbent mass (0.05 g/50 mL-0.25 g/50 mL) were determined at 25 °C. The raw data obtained from sorption tests were applied to Freundlich, Langmuir-1, Langmuir-2, Langmuir-3, Langmuir-4, Temkin, Toth, and Koble-Corrigan isotherm models. The best results were obtained from the Langmuir-2 and accordingly the qm values were calculated as 454.54, 833.33, and 625.00 mg/g for FA, FA-SA-20, and FA-SA-30 at 25 °C, respectively. Adsorption kinetic data illustrated that the process followed the PSO model. Reusability and desorption studies were performed for composite microbeads. Additionally, the thermodynamic studies were performed at 25, 35 and 45 °C. Considering all these results, it was seen that the FA-SA-20 composite had the highest adsorption capacity and the best desorption efficiency.

Removal of safranin O from wastewater using Streptomyces griseobrunneus dead biomass and in silico calculations

Removal of safranin O from wastewater using Streptomyces griseobrunneus dead biomass and in silico calculations

Green synthesised ZnO nanoparticles from Plectranthus amboinicus plant extract: removal of Safranin- O and Malachite green dyes & anti-bacterial activity

ABSTRACT The synthesis of Zinc oxide nanoparticles using a plant-mediated approach is presented in this paper. The nanoparticles were successfully synthesised using the sulphate derivative of Zinc and plant extract of the indigenous medicinal plant Plectranthus amboinicus. The XRD analysis confirms the hexagonal close-Packed lattice of the synthesised ZnO nanoparticle. In the UV visible spectrometer (UV – Vis) absorption peak was observed at 314 nm, which is specific for Zinc oxide nanoparticles. Field Emission Scanning Electron Microscope (FESEM) reveals the presence of Zinc oxide nanoparticles in its nanoflakes form. Energy Dispersive Spectrum (EDX) results show strong energy signals of 71.60% and 18.40% for Zinc and Oxygen, respectively. The absorption peak of Zn – O bonding between 404 cm−1 is confirmed by FT- IR spectra. The ZnO nanoparticles degrade 85.29% of Safranin-O dye and 81.57% of Malachite green dye within 90 minutes of time. Antibacterial studies with Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) bacteria have given more than 90% results.

Removal of Safranin O from Water by UV/TiO2/IO3− Advanced Oxidation Process: Parametric Study and Impact of Inorganic Ions and Humic Acid

In the present paper, the influence of iodate (IO3−) ions on the photocatalytic process using titanium dioxide (UV/TiO2) was systematically examined. The innovative studied system (UV/TiO2/IO3−) demonstrated high performance in the elimination of safranin O (SO), a model dye, from water due to the implication of iodine radicals (IO3•, IO2•, IO•, etc.). The degradation was assessed by monitoring the change in initial substrate concentration (5–30 mg∙L−1), TiO2 loading (0.01–3 g∙L−1), IO3− concentration, liquid temperature, and initial pH. Further enhancement of oxyanion amount was beneficial for the initial rate of degradation (r0) over the range 0.1–50 mM, such that r0 rose from 0.724 to 1.12 mg∙L−1∙min−1. However, a concentration of 100 mM IO3− slowed the removal kinetics. Low pH values were found to be favorable for pollutant removal. Furthermore, a variety of inorganic and organic substances was employed to clarify the effect of the UV/TiO2/IO3− process in natural waters. The findings revealed a negative impact of chloride excess in seawater and a decline in SO degradation in mineral water as a result of HCO3− presence at more than 1 mM. At high concentrations of natural organic matter, the heterogeneity and the strong adsorption of humic acid on the TiO2 surface were found to be harmful for SO decay.

Efficient removal of safranin from aqueous solution using a new type of metalated highly self-doped polyaniline nanocomposite

We report the chemical synthesis of poly(aniline-co-aniline-2,5-disulfonic acid)) and its composite containing L-hexuronic acid and metallic Ag/SiO2 nanoparticles as a new thermally stable anionic polyelectrolyte for removing safranin dye. The composite was characterized by IR, UV, cyclic voltammetry, SEM, TEM, TGA, DSC, EDXS and elemental analyses. Microscopic images exhibited intensified spherical particles dispersed over almost the entire surface. The XRD exhibited peaks of the partially crystalline material at many 2θ values, and their interatomic spacing and sizes were calculated. The cyclic voltammograms exhibited characteristic redox peaks relative to the quinoid ring transition states. The uptake rates up to 82.5% adsorption were completed within 75 min and the equilibrium time was 45 min. The isotherm of dye adsorption interprets the interaction with the adsorbent and explain the relationship between the dye removal capacity and the initial dye concentration. In the current, the Langmuir isotherm model was the optimum to interpret both the dye/copolymer and the dye/composite interactions. The uptake of safranin by copolymer/SiO2@Ag nanocomposite was well defined by pseudo second order model with rate constant K2 = 0.03 g− 1 mg− 1 min− 1 for 19 mg safranin. A comparison of safranin adsorption efficiency of the synthesized material with other reported material in the same domain suggested that the present composite has a higher adsorption rate and capacity. The ongoing research is devoted to improving the removal percentage of the dye by using 1,3,5-triazine based sulfonated polyaniline/Ag@ SiO2 nanocomposite.

Senegalia Catechu activated carbon incorporated Ba-alginate composite beads for the removal of Safranine B: modeling studies

The present investigation depicts the removal of Safranine-Bdye from aqueous solution using senegalia Catechu activated carbon incorporated Ba-alginate composite beads. The alginate beads were synthesized by metal encapsulation technique using BaSO4 as an encapsulating agent. The Safranine-B dye removal efficiency was determinedby the modeling equations like Langmuir and Freundlich. The nature of physical, chemical force of attractionbetween the adsorbate vs. adsorbent and feasibility was determined using pseudo order equations of first andsecond. The progressiveness of the interaction process was predicted by intraparticle diffusion, enthalpy, entropy and Gibbs free energy model equations. Experimentally obtainedoutcomes were implied that the adsorption of Safranine-Bwas feasible for all the parameters used in this study. Furthermore, the predicted diffusion valueswere revealedthat the contact between Safranine-B versus composite beads was well diffused. The surface morphology of virgin and Safranine-B loaded images confirms that the Safranine-B was strappinglybind on outerlayer of the composite. The results of the FTIR spectrum indicatethe Safranine-Bwas intensively attached on thecomposite surface. The TGA result revealsthat the Ba composite bead has predominant temperature bearing nature.

Safranin O dye removal using Senna fistula activated biomass: Kinetic, equilibrium and thermodynamic studies

The availability of potable water has decreased in recent times due to the extensive discharge of effluents from some industries. This contaminated water poses a great danger to both human and aquatic life. Senna fistula was activated using phosphoric acid, H3PO4 and its ability to remove Safranin O from aqueous solution was investigated. The characterization of Senna fistula activated carbon was done by Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy. The impacts of pH, initial dye concentration, contact time, and effect of temperature were investigated. Results showed that the optimum pH for the removal of Safranin O was 4.4. The adsorption capacity increased as the initial dye concentration increased from 30 - 130 mg/L. The dye adsorption equilibrium data were properly fitted to both Freundlich and Langmuir isotherms. The maximum uptake capacity for Safranin O was 22.1 mg/g. The kinetic studies indicated rapid sorption dynamics via a second-order kinetic model. The thermodynamic parameter shows that the sorption of Safranin O on Senna fistula activated carbon was feasible, spontaneous and endothermic. Senna fistula-activated carbon was found to be cheap and efficient adsorbents for the removal of Safranin O dye from aqueous solutions.

Agricultural Lolium perenne seeds as a low-cost biosorbent for Safranine T adsorption from wastewater: Isotherm, kinetic, and thermodynamic studies

Recently, the negative effects of organic/inorganic pollutants such as dyes and heavy metals on the environment, increasing in direct proportion with increasing industrial developments and urbanization, have become an important problem. Lignocellulosic materials have emerged as promising materials for the treatment of wastewater which is containing pollutants due to their low cost, sustainability, abundance, environmentally friendly nature, and high efficiency. In this study, Lolium perenne seeds were utilized for the adsorptive removal of Safranine T from an aqueous environment for the first time. From the adsorption results, it was determined that the adsorption process was suitable for the Langmuir isotherm (r2=0.99). As a result of the adsorption processes, it was observed that the removal of the Safranine T dye reached up to 91.37%, and the adsorption capacity was calculated as 322.58 mg/g at 25 °C and pH ≅ 7 according to the Langmuir model. From the kinetic models, it was determined that the adsorption process followed the pseudo-second-order kinetic model. Furthermore, the surface area of adsorbent seeds was calculated as 142.32 m2/g using the Langmuir model. Thermodynamic experiments also stated that the process occurred exothermically (ΔHAo=−6.38kJ/mol at 25 °C) and spontaneously (ΔGAo=−27.57kJ/mol at 25 °C) in nature. The adsorption mechanism was attributed to the electrostatic interactions, π-π, n-π interactions, and H-bonds between the functional groups of the surface of the adsorbent and dye molecules. This study suggests that Lolium perenne seeds are promising and reusable adsorbents for the treatment of wastewater.

Gellan gum/bacterial cellulose hydrogel crosslinked with citric acid as an eco-friendly green adsorbent for safranin and crystal violet dye removal

In this study, ex-situ crosslinked gellan gum (GG)/bacterial cellulose (BC) hydrogels have been investigated as good absorbents for the removal of safranin and crystal violet dye pollutants. The preparation involves a cost-effective and easy-to-perform crosslinking procedure, using citric acid (CA) as a green crosslinker. The physicochemical and mechanical properties of the crosslinked hydrogels were examined by FTIR, TGA, SEM, XRD, and unconfined compression analyses. The swelling capacity of the hydrogels as a function of pH was investigated. CA depicted to improve structural stability as a crosslinker. The dye removal capacity of the hydrogels as good adsorbents was explored and showed higher efficiency in the removal of safranin dye as compared to crystal violet with optimum adsorption capacities obtained as 17.57 and 13.49 mg/g, respectively. Adsorption kinetics and isotherm models as well as thermodynamics examined. Results showed the adsorption process well fitted the pseudo 2nd-order kinetic and Langmuir-Freundlich models while temperature dependence study depicted to be exothermic. Furthermore, no significant loss of removal efficiency of the hydrogel adsorbent was observed even after five adsorption-desorption cycles. Based on the revealed results, the prepared hydrogel may serve as an effective adsorbent for the removal of dyes from the aqueous phase.

Eco-friendly, non-toxic and super adsorbent hydrogels based on graphene

This work aimed to develop three-dimensional materials based on graphene by a simple, low-cost, and environmentally friendly method, evaluating its toxicity and capacity for the cationic dye safranin removal from water. 3D-rGO materials were obtained by reducing graphene oxide (GO) in one step and through a sustainable route. The materials were obtained over 2 h, showing a self-supporting three-dimensional structure. The effect of ascorbic acid amount as a reducing agent for this material was evaluated. It was observed that variations in the reaction promoted significant morphological changes. The results showed that the greater the reducing agent amount used in the synthesis, the more compact the three-dimensional structure, the smaller the pores and specific surface area, and the lower the number of oxygenated sites. The pH of the zero charge point (pHZCP) ranged between 2 and 2.37, indicating that the material must efficiently adsorb cationic dyes at neutral pH. Adsorption studies for the cationic dye safranin showed materials capable of adsorbing the dye quickly, with a kinetic equilibrium time of only 10 min, and a high adsorption capacity (937,841 mg g−1), in the equilibrium isotherm studies. The changes in the surface area and the compaction of the structure directly influence intraparticle diffusion and adsorption mechanisms. In addition, the materials did not present significant toxicity in D. melanogaster fly, indicating the absence of immediate toxicological risk in a situation of possible contamination.

The role of reactive chlorine species and hydroxyl radical in the ultrafast removal of Safranin O from wastewater by CCl4/ultrasound sono-process

The present study combines, for the first time, experimental degradation findings and numerical simulation results of CCl4 sonochemistry for (i) understanding the right mechanism by which CCl4 improves Safranin O (SO) sono-bleaching (1.7 MHz, 15 W) and (ii) stating the impact of operational conditions on reactive species distribution toward the degradation process. The hydrophilicity/hydrophobicity of SO are the main keys controlling its elimination as function of the solution pH in the absence of CCl4. In the presence of CCl4, a drastic enhancement in the SO degradation rate was observed. The quantity of reactive chlorine species (RCS) and reactive oxygen species (ROS) produced through CCl4 and H2O sono-pyrolysis within hot bubbles are the key parameters responsible for SO rapid degradation. Theoretical results indicated the increase of RCS and •OH production proportionally with the rise of CCl4 concentration from 0 to 5 mM, conversely to the bubble temperature and CCl4 conversion yield which were reduced. In addition, it was observed that the degradation of SO is more promoted at the liquid temperature of 25 °C, because of the synergy between RCS and •OH radicals at this liquid temperature. However, the competition between RCS and •OH radicals at 45 °C negatively affects the degradation rate.

Novel composites of Pennisetum glaucum with CNT: preparation, characterization and application for the removal of safranine O and methylene blue dyes from single and binary systems

Novel composites of Pennisetum glaucum with CNT: preparation, characterization and application for the removal of safranine O and methylene blue dyes from single and binary systems

Removal of Safranine T by a highly efficient adsorbent (Cotinus Coggygria leaves): Isotherms, kinetics, thermodynamics, and surface properties

Leaf-based adsorbents have attracted many researchers due to their low cost, high efficiency, and high adsorption capacity. In the present study, the performance of Cotinus Coggygria leaves on the adsorptive removal of Safranine T dye from an aqueous solution was investigated. Before the adsorption studies, the inverse gas chromatography (IGC) method was performed to observe the surface properties of Cotinus Coggygria, for the first time. With the data obtained from IGC analysis, the acidity/basicity degree of the adsorbent surface and the required conditions for the highest adsorption capacity were determined. The surface of the leaves was found to have a basic characteristic. The adsorption studies were carried out under different parameters including contact time, temperature, pH, initial dye concentration, and adsorbent dosage. The maximum percentage of Safranine T was obtained as 93.62% at pH = 7 and 55 °C. The different isotherms were applied namely Langmuir, Freundlich, D-R, Harkins-Jura, and Temkin isotherm models. From the correlation coefficients, it was obtained that the adsorption took place in agreement with the Langmuir isotherm. The adsorption capacity showed the maximum at 2000 mg/g in pH = 7 at 55 °C. As a result of the kinetic studies, it was seen that adsorption followed the pseudo-second-order kinetic model. When thermodynamic parameters were obtained, it was seen that the adsorption occurred exothermically and spontaneously. This study suggests that Cotinus Coggygria leaves are highly efficient biobased materials as an adsorbent.