Adsorption Isotherm Of Congo Red Research Articles

Piper chaba Stem Extract Facilitated the Synthesis of Iron Oxide Nanoparticles as an Adsorbent to Remove Congo Red Dye.

In this study, a straightforward, eco-friendly, and facile method for synthesizing iron oxide nanoparticles (IONPs) utilizing Piper chaba steam extract as a reducing and stabilizing agent has been demonstrated. The formation of stable IONPs coated with organic moieties was confirmed from UV-vis, FTIR, and EDX spectroscopy and DLS analysis. The produced IONPs are sufficiently crystalline to be superparamagnetic having a saturation magnetization value of 58 emu/g, and their spherical form and size of 9 nm were verified by XRD, VSM, SEM, and TEM investigations. In addition, the synthesized IONPs exhibited notable effectiveness in the removal of Congo Red (CR) dye with a maximum adsorption capacity of 88 mg/g. The adsorption kinetics followed pseudo-second-order kinetics, meaning the adsorption of CR on IONPs is mostly controlled by chemisorption. The adsorption isotherms of CR on the surface of IONPs follow the Langmuir isotherm model, indicating the monolayer adsorption on the homogeneous surface of IONPs through adsorbate-adsorbent interaction. The IONPs have revealed good potential for their reusability, with the adsorption efficiency remaining at about 85% after five adsorption-desorption cycles. The large-scale, safe, and cost-effective manufacturing of IONPs is made possible by this environmentally friendly process.

Optimization on Adsorption Process of Congo Red onto Magnetic Ni0.5Cu0.5Fe₂O₄/SiO₂ Nanocomposites and Their Adsorption Mechanism.

Magnetic Ni0.5Cu0.5Fe₂O₄/SiO₂ nanocomposites were prepared via a solution combustion process, and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), Energy dispersive X-ray Spectroscopy (EDX) and vibrating sample magnetometer (VSM). The magnetic Ni0.5Cu0.5Fe₂O₄/SiO₂ nanocomposites were employed to remove Congo red (CR) from aqueous solution, and the adsorption process was optimized by response surface methodology (RSM). The optimum conditions were the silica content of 12.6 wt%, the calcination temperature of 501 °C and the pH value of 7.13. The adsorption kinetics and the adsorption isotherm of CR onto magnetic Ni0.5Cu0.5Fe₂O₄/SiO₂ nanocomposites at room temperature were investigated, and the intraparticle diffusion kinetics model and Redlich-Peterson isotherm model fitted well the respective process.

Study on the adsorption and desorption performance of magnetic resin for Congo red

ABSTRACT This study was to evaluate the adsorption capability of a magnetic resin (NDMP) to the removal of Congo red (CR) from aqueous solution. The adsorption kinetic and isotherm of NDMP were studied, as well as the desorption performance of NDMP. The results showed that the adsorption process of NDMP on CR was more suitable for Pseudo-second-order kinetic model. The whole adsorption process was affected by intraparticle diffusion and ion exchange. The adsorption isotherm of CR by NDMP was fitted better with Langmuir model. It showed that the adsorption of CR on NDMP resin was single layer adsorption. The maximum adsorption capacity (Qm ) of CR at 308 K can reach 354.29 mg/g. In the desorption, 10% NaCl and NaOH eluents had better desorption rate for CR than other mass fraction. While NaCl(10%)-MeOH mixed eluent with volume ratio of 3:7 had the best regeneration performance. The desorption rate can reach 90% within 30 min. The adsorption performance of NDMP on CR didn't decrease after 13 times successive adsorption–desorption by NaCl(10%)-methanol eluent, indicating that NDMP can be efficiently regenerated. The excellent adsorption–desorption performance of NDMP on CR suggests that the magnetic resin has a great potential for treating CR dye wastewater.

Fabrication of zwitterionic histidine/layered double hydroxide hybrid nanosheets for highly efficient and fast removal of anionic dyes

In this work, the bio-nanohybrids of magnesium-aluminum layered double hydroxide intercalated with zwitterionic histidine (His-LDH) was synthesized. The crystal phase, morphology, and nanostructure of the as-prepared His-LDH were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and nitrogen adsorption–desorption methods. The His-LDHs were used to remove anionic dyes, including Congo red (CR), indigo carmine (IC) and sunset yellow FCF (SY) from aqueous solutions. The detailed investigation of the kinetics and the adsorption isotherms of CR, IC and SY from aqueous solutions showed that the dyes adsorb rapidly, in accordance with a pseudo-second-order kinetics and a Freundlich adsorption isotherm model. The remarkably high adsorption capacity of the dyes on the His-LDH (efficiency of CR removal, 99.98%; maximum specific removal qmax, 1112 mg g−1; efficiency of IC removal, 98.98%; qmax, 625 mg g−1; and efficiency of SY removal, 99.78%; qmax, 400 mg g−1) is rationalized on the basis of electrostatic interactions as well as π-π and H-bonding interactions between the His-LDH adsorbent and the acidic dyes. Adsorption experiments indicate that the resulting His-LDH has great potential applications as an environmentally friendly material for the swift removal of acidic dyes from aqueous solutions.

Oxygen functionalized carbon nanocomposite derived from natural illite as adsorbent for removal of cationic and anionic dyes

Oxygen functionalized carbon nanocompositse (O-I@C) based on glucose and illite were obtained through mild hydrothermal process and surface oxidation. The surface properties of the prepared O-I@C were analyzed by Boehm titration, scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and Specific surface area (BET). The results showed that the surfaces of the prepared O-I@C nanocomposites were functionalized with abundant oxygen-containing functional groups (OFGs). The functionalized O-I@C nanocomposites were proven to be effective adsorbents for fast removal of congo red (CR) and methylene blue (MB) from aqueous solution within 10min. It is demonstrated that the initial pH of dyes solution has an important influence on the adsorption process of both CR and MB, indicating that the OFGs created on the surfaces of the materials are responsible for the promoted adsorption ability. Furthermore, it is also proved that the adsorption isotherms of CR and MB obey the Langmuir model, with the maximum adsorption capacities of 238.40mg/g and 215.28mg/g, respectively. In addition, the used materials could be regenerated by washing with NaOH solution and reused at least four times, which exhibits potential applications as efficient and easily reusable adsorbents for the rapid removal of anionic dye CR and cationic dye MB from wastewater.

Fabrication of Magnetic NiFe2O4 Nanorods and Their Removal Performances of Congo Red.

Magnetic NiFe2O4 nanorods were prepared successfully via a facile solution combustion process, the morphology, chemical composition, microstructure and magnetic properties of as-prepared NiFe2O4 nanorods were investigated by XRD, VSM, SEM, TEM, EDX, SAED and BET techniques. The magnetic NiFe2O4 nanorods were characterized with average length of about 130 nm, the diameter of around 25 nm, the specific magnetization of 105.2 Am2/kg, and the specific surface area of 88.8 m2/g. The nanorods were employed to remove congo red (CR) from aqueous solutions, the adsorption kinetic and adsorption isotherm of CR onto NiFe2O4 nanorods at room temperature were investigated. The regression equation was found in good agreement with the pseudo-second-order kinetic model in a range of initial CR concentrations of 80-400 mg/L. Compared with Freundlich and Temkin models, Langmuir model fitted the adsorption isotherm of CR onto NiFe2O4 nanorods better, which suggested that the adsorption of CR onto NiFe2O4 nanorods was a monolayer absorbing mechanism. Meanwhile, the adsorption capacity of CR onto NiFe2O4 nanorods is large when pH is less than 9.

Cranberry Stem as an Efficient Adsorbent and Eco-Friendly for Removal of Toxic Dyes from Industrial Wastewater, Physico Studies

The adsorption of Congo red (CR) from aqueous solution using treated ground cranberry stem by varying the parameters such as contact time, dye concentration, adsorbent dose, pH and temperature was investigated. Adsorption isotherms of CR onto CS were analyzed by Langmuir and Freundlich. It was observed that the optimum CR adsorption onto ground CS occurred at contact time of 30 minutes, the adsorbent dosage of 8 g, initial concentration of 50 mg/L and pH 2. In addition, the particle size of ground CS has no significant effect on the adsorption of CR. Adsorption isotherms studied through the use of graphical methods revealed that the adsorption of CR onto cranberry stem follows both Langmuir and Freundlich models, with the maximum adsorption capacity was 95.25mg g-1. The ground cranberry stem investigated in this study thus exhibited as a high potential adsorbent for the removal of CR from aqueous solution.

Use of 4-vinylpyridine and 2-hydroxyethylmethacrylate monomer mixture grafted poly(ethylene terephthalate) fibers for removal of congo red from aqueous solution

AbstractIn this study, a novel fibrous adsorbent made by grafting 4-vinyl pyridine (4-VP) and 2-hydroxyethylmethacrylate (HEMA) monomer mixture onto poly(ethylene terephthalate) (PET) fibers was used for removal of Congo red (CR) in aqueous solutions by a batch equilibration technique. The influence of treatment time, pH of solution, dyes concentration, and reaction temperature on adsorbed amount was investigated. Adsorption time of 60 min. was found sufficient to reach adsorption equilibrium for CR. It was found that the adsorption isotherm of CR fits to Langmuir type isotherms. The highest adsorption capacity was found to be 11.87 mg CR per gram adsorbent. The adsorption rate of CR is much higher on the comonomers grafted PET fibers than on the ungrafted PET fibers. CR was removed 97 % when the initial dye concentration was 5 mg L-1 and 38% at 150 mg L-1 by monomers mixture grafted PET fibers. The adsorption of the dye was endothermic in nature (ΔH°=45.3 KJmol-1). It was found that the reactive fibers are stable and regenerate by acid without losing its activity.

Adsorption properties of Congo Red from aqueous solution onto surfactant-modified montmorillonite

A series of surfactant-modified montmorillonites (MMT) were prepared using octyltrimethylammonium bromide (OTAB), dodecyltrimethylammonium bromide (DTAB), cetyltrimethylammonium bromide (CTAB) and stearyltrimethylammonium bromide (STAB), and the organification of MMT was proved by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron micrographic (SEM) and transmission electron microscope (TEM). The adsorption of Congo Red (CR) anionic dye from aqueous solution onto surfactant-modified MMT was carried out. Compared with MMT, the adsorption capacity of surfactant-modified MMT for CR was greatly enhanced and MMT modified with CTAB (2.0 CEC) exhibited the higher adsorption capacity. The effects of pH value of the dye solution, adsorption temperature, adsorption time and the initial dye concentration on the adsorption capacity of CR on CTAB-MMT have been investigated. The results showed that the adsorption kinetic of CR on CTAB-MMT could be best described by the pseudo-second-order model and that the adsorption isotherm of CR was in good agreement with the Langmuir equation. The IR spectra and SEM analysis also revealed that the adsorption of CTAB-MMT was a chemical adsorption process between CTAB and the NH 2, –N N– and SO 3 groups of CR.

THE SATURATION VALUE OF ADSORPTION OF THE SURFACE LAYER OF CELLULOSE IN DIRECT DYEING

Adsorption isotherms of Congo Red, Benzopurpurine 4 B and Benzopurpurine 10 B, from the dyebath within the range of concentrations 1.5×10-3 mole dyes per litre have been determined on cellophane sheets.The results of these experiment are as following:The ratio between the ionic products of dye anion and Na ion concentrations from dyebath and from cellophane sheet cease to maintain the constant value, in case where the cellophane sheet adsorbs more than about 4×10-2 mole per kg. This result is due to the fact that the adsorption amount is closely connected with the saturation value; for that reason, this tendency becomes more conspicuous as the adsorption amount goes on increasingly.