Low-cost Adsorbent For Dye Removal Research Articles

Study of adsorption mechanism of Malachite Green (MG) and Basic Yellow 28 (BY28) onto smectite rich natural clays (Ghassoul) using DFT/B3LYP and DOE/FFD

The current study aims to investigate the behavior of local and natural clays rich in smectite (Ghassoul) collected in the region of Fez (North-East of Morocco) and valorize it in order to eliminate the two cationic dyes, malachite green (MG) and basic yellow 28 (BY28), which are hazardous on the environment as a result of the human trail, from aqueous solutions and to understand better the adsorption mechanism at the clay/dyes interface. Batch experiments were done to evaluate the influence of operational factors on the adsorption process and were compared to the static research to clarify the adsorption process. In addition, the experimental data were analyzed by Langmuir and Freundlich isotherms to describe the adsorption equilibrium. The Langmuir model perfectly describes the equilibrium, with a correlation coefficient greater than 0.998 with a maximum adsorption capacity of 588 mg g−1 for BY28 and 500 mg g−1 for MG. The experimental data fit well according to the pseudo-second-order kinetic model with a correlation coefficient of 0.998. Density function theory (DFT/B3LYP) was used to interpret better the adsorption mechanism and experimental design (DOE/FFD) to determine the factors influencing this mechanism. Experimental analytical data and theoretical calculations by DOE showed that BY28 has a higher adsorption affinity than MG DFT modeling of the two molecules in their steady-state allowed us to determine the reactivity's origin, allowing both dyes to establish der walls bonds with the clay. The results of the present study show that Ghassoul, a stevensite-rich clay abundant in the Mediterranean coastline, America, and Asia, can be advantageously used as a low-cost adsorbent for dye removal from wastewater.

Calcined sugar scum as a low-cost adsorbent for dye removal from aqueous solution: Equilibrium, kinetic and modeling

<p>Batch adsorption experiments have been conducted to investigate the adsorption properties of the calcined sugar scum powder for methylene blue (MB) and methyl orange (MO) as models for cationic and anionic dyes. The kinetic and equilibrium adsorption have been investigated to determine the adsorption mechanisms and the adsorption capacities. The kinetic of adsorption was examined by pseudo-first order, pseudo-second order and intraparticle diffusion models. Adsorption isotherm was modeled using Langmuir, Freundlich. The methylene blue adsorption process can be best described by the pseudo-first order kinetic and Langmuir adsorption isotherm models while the methyl orange adsorption process was best fitted to the Langmuir isotherm with a monolayer maximum adsorption capacity of 40.28 mg/g. Moreover, both pseudo-first order and pseudo-second order models could be used to describe the adsorption process of methyl orange. The percentage removal of the calcined sugar scum powder was found greater than 98 % and 87 % for MB and MO, respectively. The results demonstrated that sugar scum is a suitable precursor for the preparation of efficient adsorbent for removal of cationic and anionic dyes.</p>

Structural Characterization and Adsorption Properties of Dunino Raw Halloysite Mineral for Dye Removal from Water.

In this work, raw halloysite mineral from Dunino (Poland) has been characterized and tested as an efficient and low-cost adsorbent for dye removal from water. The morphology and structure of this clay were characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and the chemical composition was evaluated by means of X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), and electron energy loss spectroscopy (EELS). The results showed that it is made up of both platy and tubular structures, mainly composed of Si, Al, and O. Iron oxide particles covering the platy structures were also observed. The surface charge of halloysite was measured by z-potential measurements and by the evaluation of the point of zero charge. The clay was tested as an adsorbent for the removal of positively and negatively charged dye molecules, i.e., methylene blue (MB) and methyl orange (MO), both separately and in a mixed-dye solution. Halloysite showed the ability to efficiently and selectively remove MB molecules by adsorption, both in a single-dye solution and in a mixed one. The adsorption of positive dyes on the clay surface mainly occurred through ion exchange at negatively charged sites on its surface. The possibility of regenerating the clay for further dye removal processes is also shown.

Bentonite Modified by Allylamine Polymer for Adsorption of Amido Black 10B.

The main object of this work is to remove Amido black 10B using a new type of bentonite-based adsorbent with cationic groups by the modification of polyallyl amines between the interlayers of bentonite. Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy were used to characterize the functionalized bentonite. A series of batch adsorption experiments were performed. The maximum adsorption amount was 144.08 mg g−1 when the pH was 2 and the contact time was 120 min. In addition, the equilibrium isotherm data were analyzed using Langmuir and Freundlich isotherm models, while only the Langmuir model could provide a high correlation. Therefore, this study provided a new functionalized bentonite as a low-cost adsorbent for dye removal from water.

Synthesis and Characterization of Ion Exchanger based on Waste Cotton for Dye Removal from Wastewater

GLYCIDYL methacrylate (GMA) polymerization with waste cotton fabric by utilizing a co-initiator of ferrous cellulose thiocarbonate–hydrogen peroxide redox system was first studied under various conditions. These include the polymerization time, temperature, liquor ratio, pH and concentrations of the initiator and monomer. The product cellulose-poly(glycidyl methacrylate) graft copolymer (CPGMA) produced at best polymerization conditions was then functionalized with triethylammonium chloride (TEAC), aiming to obtain a low-cost adsorbent for dye removal from wastewater. Also, factors that affecting the amination reaction, which include; reaction time, temperature, liquor ratio, pH, and aminating agent/epoxy molar ratio were studied. The prepared amino-functionalized cellulose-poly(glycidyl methacrylate) graft copolymer (AM-CPGMA) was further characterized by the FT-IR, thermal gravimetric analysis (TGA) and surface area measurement based on Brunauer–Emmett–Teller (BET) and Barrett-Joyner-Halenda (BJH) theories. The dye adsorption capacity of the anion exchanger was also evaluated.

Experimental Study to Remediate Acid Fuchsin Dye Using Laccase-Modified Zeolite from Aqueous Solutions

This paper studies, the removal of acid fuchsin dye from aqueous solutions using zeolite natural material after its modification with laccase from Russulaceae (Lactarius volemus). Batch adsorption experiments were performed as a function of pH, contact time, temperature, and adsorbent dosage. The optimum results were obtained at pH 5, contact time of 60 min, temperature of 60oC, and an adsorbent dosage of 1.5 mg/mL. The isotherm studies show that the adsorption experimental data are fitted well by Langmuir isotherm model. The adsorption capacity found is 31 mg/g. The kinetics of AFD adsorption on LMZ is best described with the pseudo-first-order kinetics model. Thermodynamic parameters including Gibbs free energy, enthalpy, and entropy changes indicate that the adsorption of Acid Fuchsin dye onto laccase-modified zeolite is feasible, spontaneous, and exothermic. The results show that laccase-modified zeolite can be used as an alternative lowcost adsorbent for dye removal from aqueous solutions.

Comparison of color removal from reactive dye contaminated water by systems containing fungal biosorbent, active carbon and their mixture.

The adsorption of Everzol Black (EB) from synthetic aqueous solution onto active carbon (AC) and dried fungal biosorbent (Rhizopus arrhizus) was studied under the same experimental conditions. The effects of initial dye concentration, adsorbent dosage and contact time were examined at a batch-scale level. As an alternative to AC, fungus was investigated as a low-cost adsorbent for dye removal. The amount of EB adsorbed onto AC was lower compared with fungal biosorbent; dye adsorption capacity of AC and fungal biosorbent were 94.48 and 106.61 mg/g, respectively. The adsorbent dosage experiments showed that 4 g/L biosorbent removed 100% of EB (Co: 114.39 mg/L) after 2 hours. The results obtained from this study showed that biosorbent effectively removed reactive dye from dye-containing water in a short time period. Langmuir and Freundlich adsorption isotherm models were used for mathematical description of the biosorption equilibrium data; the Freundlich model was found to exhibit good fits to the experimental data. According to the Freundlich isotherm, the maximum dye adsorption capacities of AC and biosorbent were calculated as 344.82 and 357.14 mg/g, respectively. The Fourier transform infrared spectroscopy spectral analysis showed the involvement of functional groups for dye bindings.

Fish Bone as a Low-Cost Adsorbent for Dye Removal from Wastewater: Response Surface Methodology and Classical Method

This research studied the application of fish bone as a low-cost adsorbent for the removal of two basic dyes (C.I. Basic Blue 41 and C.I. Basic Yellow 28) from textile wastewaters. The surface morphology and functional groups of the fish bone was studied by scanning electron microscopy and Fourier transform infrared, respectively. The experiments were designed in two methods: classical method and response surface methodology (RSM). The effect of operating parameters including pH, initial dye concentration, adsorbent dosage, and inorganic salts was investigated by both methods. The optimum conditions to satisfy 75 % of dye removal for both dyes were predicted by RSM method and the results were very close to the experimental values. So, it was concluded that the fish bone can be used as a low-cost adsorbent for dye removal from effluents.