Pseudo 2nd Order Model Research Articles

Porous three-component hybrid hydrogen-bonded covalent organic polymers: Design, synthesis and ciprofloxacin adsorption

Since the great risks posed by fluoroquinolones arise much concerns, it is required a prompt action to establish efficient adsorbents with excellent behaviors for adsorptive removal in remediation management. Herein, three porous three-component hybrid hydrogen-bonded covalent organic polymers were reasonably designed and successfully prepared via orthogonal reactions based on Schiff-base chemistry and hydrogen-bonding. The resulting polymers were used to remove a model fluoroquinolone antibiotic, ciprofloxacin (CIP), from wastewater. The benzene-1,3,5-tricarbohydrazide (BTCH) and 1,3-di(4-pyridyl)propane (BPP) reacted with 4,4′-biphenyldicarboxaldehyde (BPDA) (JLUE-HCOP-7) and exhibited the profound highest adsorption capacity for CIP as 84.03 mg/g, followed by the reaction of BTCH, BPP and terephthalaldehyde (TPA) (JLUE-HCOP-6), and the reaction of BTCH, 4,4′-bipyridine (BPY) and TPA (JLUE-HCOP-5). The adsorption processes were systematically investigated through batch adsorption experiments. Most of the CIP were removed within 12 h; moreover, the kinetic data and isothermal data were well fit with the pseudo 2nd order model and Langmuir model, respectively. In addition, the high adsorption affinity may be attributed to porousness advantage, electrostatic interactions, hydrophobic effect, electron donor–acceptor (EDA) interactions and hydrogen bonding.

Nanoionic exchanger with unprecedented loading capacity of uranium

Nanocomposite materials as innovative environment and energy materials require superbly isolation performance to apply in practice. Here we report successful grafting of polyethylenimine (PEI) on multiwall carbon nanotubes (MWCNTs-PEI) which was characterized using different techniques. The forier transform infrared (FTIR) and thermogravimetric analysis (TGA) analyses showed that PEI was successfully grafted on the oxidized surface of MWCNTs, which shows exceptionally high uptake capacity and stability towards U(VI) ions. The performance of MWCNTs-PEI adsorption characteristics was evaluated at different conditions including initial U(VI) concentration, adsorbent dosage, pH and contact time. The pH was found to have great effect on the adsoption process; the highest adsorption capacity obtained was found in pH range of 6.5–8.7. The experimental uptake of the fabricated MWCNTs-PEI nanocomposite ion-exchanger was found to be 947 mg U/g (nanocomposite), while the one calculated according to Langmuir model was found to be 997 mg/g with an (R2) of 0.978; the largest value reported to date for uranium extraction using MWCNTs based adsorbents from aqueous solutions. Additionally, four consecutive adsorption–desorption cycles suggesting that the synthesized MWCNTs-PEI had exceptional reversibility and stability for uranium isolation from aqueous solutions. This could be due to the synergetic effect of both carboxyl and amine groups attached to the surface of MWCNTs-PEI nanocomposite. The kinetics of the adsorption were best fitted to the pseudo 2nd order model. The MWCNTs-PEI prepared in this work could have great potential for U(VI) separation from aqueous solutions if turned into magnetic for easy separation.

Kinetic and Isotherm Study of Ammonium Sorption Using Natural Zeolites from Lampung

The aims of the study were to characterize and investigate the ammonium adsorption kinetic and isotherm of the natural zeolites from Lampung. Characterization of the natural zeolite was performed by using X-Ray Diffraction (XRD), nitrogen-physisorption, Scanning Electron Microscope (SEM) and X-Ray Fluorescence (XRF). According to XRD analysis, the natural zeolites were identified as clinoptilolite dominant phase with some impurities i.e. mordenite and quartz. The surface area calculated by BET model was 45 m2/g. The SEM images showed the irregular morphology shape. The XRF analysis revealed that the ratio Si/Al was 6.2. Ammonium sorption experiment was performed by using 100 ppm of ammonium solution in the batch reactor with variation on natural zeolite mass loading and adsorption time. Ammonium adsorbed onto the zeolites was increased with the adsorption time and mass loading. The kinetic models, i.e. Lagergren’s 1st order, Pseudo 2nd order, Elovich, Intraparticle diffusion, and isotherm models, i.e., Langmuir, Langmuir-Vageler, Freundlich, Temkin were fitted with the ammonium adsorption kinetic data by using non-linear regression analysis in MATLAB.

Bioinspired modified nanocellulose adsorbent for enhanced boron recovery from aqueous media: Optimization, kinetics, thermodynamics and reusability study

In this current study, platelet-shaped gels of amino modified nanocellulose (A-NCC) were facilely prepared and applied for the enhanced recovery of boron from aqueous media. The gels were characterized using FTIR, XRD, SEM, BET, TGA and the results revealed good thermal as well as mechanical stability. Optimization by Taguchi design model was further applied to investigate the significance of input adsorption factors influencing boron recovery from aqueous phase. Under optimized conditions, 87.38% (≈120.9 mg boron/g of A-NCC) boron recovery was achieved at pH 7. Kinetic evaluations determined the pseudo 2nd-order model (R2 = 0.997) to best describe the adsorption process mainly via intraparticle diffusion. Thermodynamic studies confirmed the adsorption process was spontaneous and exothermic in nature. In addition, reusability capacity of the adsorbent proved significant for at least four consecutive adsorption/desorption cycles with minimum recovery efficiency loss.

Adsorptive removal of acidic dye onto grafted chitosan: A plausible grafting and adsorption mechanism

In the present research, a biopolymer Chitosan (C) grafted with ethylenediamine (EDA) and methyl acrylate (MA) were compared for the adsorption of Congo red dye from aqueous phase. The grafted chitosan product was characterized by Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Differential scanning calorimetry (DSC), X-ray diffraction (XRD) and point of zero charge to study the change in mechanical and thermal properties. The effects of process variables like adsorbent loading, initial dye concentration, initial solution pH, contact time and temperature on adsorption phenomena were investigated. The equilibrium isotherm data was analyzed using Langmuir and Freundlich isotherm models, and the adsorption followed the Langmuir isotherm model (R2 = 0.992 and 0.991 for EDAC and MAC, respectively). The maximum adsorption capacity of EDAC and MAC for Congo red uptake calculated from Langmuir isotherm model was 1607 mg/g and 1143 mg/g, respectively. The adsorption kinetics was studied using pseudo 1st and 2nd order models. Pseudo second order rate model provided the best fit for both grafted adsorbents with R2 ≥0.99. The values of Gibbs free energy (−9.628 and −8.878 kJ/mol), enthalpy (44.9 and 42.2 kJ/mol) and entropy (0.18 and 0.17 J/mol·K) revealed spontaneous and endothermic adsorption of Congo red onto EDAC and MAC surface. The pollutant adsorption test indicated that chitosan grafting with ethylenediamine is superior to Methyl acrylate grafting agent.

Use of CaO Loaded Mesoporous Alumina for Defluoridation of Potable Groundwater Containing Elevated Calcium Levels

Defluoridation in the presence of high calcium levels in potable groundwater is paramount, as the consumption of groundwater enriched with fluoride, and calcium has been implicated in causing chronic kidney disease of unknown etiology (CKDu) in Sri Lanka. CaO loaded mesoporous alumina (COMA) offers a great potential for defluoridation of potable water, but the effectiveness of COMA in the presence of calcium has not been investigated. This study, therefore, focuses on the investigation of the suitability of COMA for the defluoridation of potable water with high calcium levels. Mesoporous alumina was successfully functionalized with CaO to synthesize nano-level COMA with an optimum dosage for defluoridation being 2 g L−1. The amount of fluoride adsorbed increased (2.4–19.5 mg g−1) with the increase of the initial fluoride concentration (5–40 mg L−1), and the residual fluoride levels (0.8–1.47 mg L−1) were within the range specified by the WHO for drinking water. The amount of fluoride adsorbed by COMA varied between 6.50 and 7.97 mg g−1 with initial calcium levels between 0 and 1500 mg L−1, indicating that defluoridation was effective in the presence of high calcium levels. The fluoride adsorption was best fitted with the Langmuir model with a maximum monolayer capacity of COMA being 17.83 mg g−1, and adsorption kinetics fitted with the pseudo-2nd order model indicating strong covalent bonding by way of chemisorption. Thus, COMA can be effectively utilized as an adsorbent material in defluoridation efforts in areas prevalent with CKDu in the presence of high fluoride (15 mg L−1) and calcium (1500 mg L−1) levels.

Kinetics and Equilibrium Studies of Eriobotrya Japonica: A Novel Adsorbent Preparation for Dyes Sequestration

Abstract Present study deals with use of agricultural based waste material Loquat (Eriobotrya japonica) seeds for removal of toxic Acid orange 7 (AO7) dye from aqueous streams. Batch mode experiments were conducted as function of pH, initial dye concentration, contact time and dosage of adsorbent. Biomass was used in native, pretreated and immobilized forms. Maximum removal was observed at pH 2. Desorption studies were done in order to determine degree of stability and regeneration of immobilized biomass. For equilibrium studies, Langmuir and Freundlich models were applied. Pseudo 1st & 2nd order models were applied on experimental data for reaction kinetics evaluation. Pseudo 2nd order model was best fit for present experiments. Biomass characterization was done by scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) and Fourier Transform Infrared (FTIR) techniques for elucidation of biomass constituents and surface morphology before and after dye loading. It was observed that loquat seeds may be potential adsorbent for removal of toxic dyes from wastewater.

Enhanced Removal of Phosphates by the Adsorbent Consisting of Iron Oxide Loaded on Porous Chitosan/Cellulose Acetate Particle

The effective and economical removal of phosphates from aqueous solution, mostly applied in waste water treatment, is one of the significant issues globally. Removal of phosphates ions in aqueous solution was analysed by chitosan blended with cellulose acetate, and iron oxide loaded chitosan-cellulose acetate adsorbents. The adsorbents were made in the form of beads. Batch experiments were performed to investigate the performance of the beads under various conditions on phosphate adsorption. Contact time, effect of initial phosphate concentration, adsorbent dosage, pH and temperature were investigated. Zeta potential measurements were also undertaken. The results showed that the adsorption process was highly pH dependent. The adsorption kinetics data were modelled with the application of adsorption reaction models and adsorption diffusion models. The results revealed that the pseudo 2nd order model was the best fitting in all cases. The experimental data were tested with Langmuir and Freundlich isotherms. The equilibrium data were well fitted to the Langmuir isotherm model with a maximum adsorption capacity of 958 μg/g. The Freundlich isotherm model also had a close fit with a maximum adsorption of 233 μg/g, which was very close to the experimental maximum adsorption. The mechanism of adsorption followed two stages in which the first one was fast followed by a slower gradual stage. SEM images showed that the adsorbent was macroporous. Fourier Transform Infrared Red (FT-IR) Spectroscopy, X-ray Diffraction Spectroscopy (XRD) and X-ray photoelectron Spectroscopy (XPS) showed that the phosphate adsorption on the HFO-CS/CA beads was due to surface complexes, and mainly involved Nitrogen atoms. HFO loading also increased surface area.

Equilibrium and kinetic studies for silver removal from aqueous solution by hybrid hydrogels.

Hybrid hydrogels were prepared by blending Carboxymethyl chitosan (CMCts), Carboxymethyl cellulose (CMC) with Sodium sulfonate styrene (SSS) by 60-kGy gamma rays. The prepared hydrogels were utilized as silver-ion (Ag) sorbent under non- and competitive cases. Batch adsorption experiments were conducted in functional conditions including contact time, ratios of (CMC:CMCts) and SSS, pH value, temperature and adsorbent weight. Equilibrium contact time of 10 h. was obtained by the adsorption material. The optimal 4:2 ratio of (CMC:CMCts):SSS showed the Ag highest adsorption efficiency. The maximum percentage of Ag+ removal was achieved at the pH 5. The temperature effect on the adsorption ability of hybrid hydrogel indicated the Ag adsorption process was endothermic and spontaneous. The Langmuir isotherm model fitted Ag adsorption data well, assuming a monolayer adsorption with predicted maximum adsorption capacity of 451.74 × 10-3 mg. g-1. From the kinetic data, the process of Ag adsorption had higher agreement with the pseudo-2nd order model, predicting the amount of Ag+ uptake at different contact time intervals and at equilibrium.

Efficient sono-sorptive elimination of methylene blue by fly ash-derived nano-zeolite X: Process optimization, isotherm and kinetic studies

Sono-assisted adsorptive elimination of dyes from industrial effluent is proved to be a fast, efficient and clean technique. Highly pure nanozeolite X (nFAZX) was synthesized from waste coal post-combustion fly ash (CFA) by pre-fusion hydrothermal method. Rapid sono-assisted adsorptive elimination of methylene blue (MB) dye from water solution was studied in presence nFAZX, CFA and commercial zeolite X (CZX). As-synthesized nFAZX, raw CFA, and CZX have been characterized by means of X-ray fluorescence (XRF), X-ray diffraction (XRD), fourier transform infrared (FTIR), transmission electron microscopy (TEM), field emission Scanning electron microscopy (FESEM), and Brunauer Emmett Teller (BET) adsorption/desorption isotherms for surface area analysis. The influence of adsorption variables, for example solution pH (3-11), adsorbent dose (0.05–0.25 g/100 ml), sonication time (2.50–12.50 min), and initial dye concentration (12.50–62.50 mg/L), on the % elimination of MB was explored by response surface methodology (RSM). Maximum MB removal (64.52% by CFA, 99.30% by nFAZX, and 96.57% by CZX) was obtained at pH 8.25, 0.164 g/100 ml of adsorbent, 9.92 min sonication time, and 25 mg/L MB concentration. The adsorption isotherms and kinetic models were best fitted with Langmuir isotherm and pseudo 2nd order model respectively for all three adsorbents. Also, the maximum Langmuir adsorption capacity of CFA, nFAZX and CZX for MB were 78.22 mg/g, 345.36 mg/g, and 250.41 mg/g respectively for 0.160 g/100 ml adsorbents. The experimentation demonstrated a route of development of a cheap, eco-friendly sorbent nFAZX as well as a green, rapid and highly efficient protocol of treating synthetic dyes which are often present in real textile wastewater.

Efficacy of spent black tea for the removal of nitrobenzene from aqueous media

Nitrobenzene (NB) is a kind of persistent organic pollutant. A ubiquitous and cost-effective substance spent black tea (SBT) was investigated for the removal of nitrobenzene from aqueous media. The maximum uptake potential of dried biomass (SBT) for NB was found to be 14.86 mg per gram (qmax) in a batch experimental set-up. Equilibration time for NB sorption was about 50 min, and optimal removal efficiency was achieved at a dosage of 2 g/L with an initial concentration of 100 mg/L of NB. Findings revealed that NB uptake increased with an increase in the temperature from 273 K to 353 K. Sorption was also found to be pH sensitive, sorption improved as the pH value changes from alkaline to acidic (from 10 to 2). Different isotherm (Langmuir, Freundlich, Temkin and Dubinin Radushkevich) and kinetic models (pseudo-1st order, pseudo-2nd order and Elovich models) were applied to experimental results; the sorption mechanism was well described by the Freundlich and pseudo-2nd order models. Moreover, Scanning electron micrographs, ATR-FTIR spectra and the results of elemental analysis also supported the efficacy of SBT as an efficient bio-sorbent for the elimination of NB from water.

Application of vermiculite-derived sustainable adsorbents for removal of venlafaxine

Removal of emerging pollutants, such as pharmaceuticals, from wastewater is a challenge. Adsorption is a simple and efficient process that can be applied. Clays, which are natural and low-cost materials, have been investigated as adsorbent. In this work, raw vermiculite and its three modified forms (expanded, base, and acid/base treated) were tested for removal of a widely used antidepressant, venlafaxine. Adsorption kinetics followed Elovich's model for raw vermiculite while the pseudo-2nd order model was a better fit in the case of other materials. Equilibrium followed Langmuir's model for the raw and the acid/base-treated vermiculite, while Redlich-Peterson's model fitted better the expanded and the base-treated materials. The adsorption capacity of vermiculite was significantly influenced by the changes in the physical and chemical properties of the materials caused by the treatments. The base-treated, raw, and expanded vermiculites showed lower maximum adsorption capacities (i.e., 6.3 ± 0.5, 5.8 ± 0.7, 3.9 ± 0.2mgg-1, respectively) than the acid/base-treated material (33 ± 4mgg-1). The acid/base-treated vermiculite exhibited good properties as a potential adsorbent for tertiary treatment of wastewater in treatment plants, in particular for cationic species as venlafaxine due to facilitation of diffusion of the species to the interlayer gallery upon such treatment. Graphical abstract ᅟ.

Synthesis of a recyclable mesoporous nanocomposite for efficient removal of toxic Hg 2+ from aqueous medium

Abstract A mesoporous magnetic zirconium phosphate was prepared for the removal of Hg2+ from aqueous medium. The saturation magnetization of pure Fe3O4 and Fe3O4@ZrP was observed 82.9 and 62.4 emu/g, respectively. The effect of different adsorption parameters was studied. The kinetic data were fitted to the pseudo 1st and pseudo 2nd order models whereas the adsorption process was best fitted into the pseudo 2nd order model. The adsorption isotherm could be well described with Langmuir model, with the maximum adsorption capacity of 181.8 mg g−1 at 25 °C. Thus, the present studies suggested that Fe3O4@ZrP have remarkable potential for Hg2+ removal from contaminated water.

Adsorptive removal of antibiotic sulfonamide by UiO-66 and ZIF-67 for wastewater treatment

Adsorptive removal of a toxic sulfonamide antibiotic, sulfachloropyradazine (SCP), from aqueous solution was studied on several metal organic frameworks, UiO-66 and ZIF-67, for the first time. UiO-66 exhibited a much higher adsorption capacity than ZIF-67, fast kinetics, and easy regeneration for reuse, demonstrating as a promising adsorbent in wastewater treatment processes. The batch adsorption shows an adsorption capacity of SCP at 417mg/g on UiO-66. The kinetic adsorption of SCP on UiO-66 reached equilibrium just in 10min and the kinetics fits accurately with a pseudo 2nd order model. A plausible mechanism was proposed based on pH effect, pKa value of the adsorbate and Zeta potential of UiO-66. The high adsorption is mainly contributed to hydrophobicity and π-π interactions along with electrostatic interactions. Thermodynamic studies show the spontaneous adsorption and exothermic process. The easy regeneration and high adsorption capacity confirms structural stability of the robust UiO-66 in wastewater treatment processes, making it suitable for a large scale application.

Fabrication and characterization of novel macroporous Jeffamine/diamino hexane cryogels for enhanced Cu(II) metal uptake: Optimization, isotherms, kinetics and thermodynamic studies

In this study, the role of optimized Jeffamine/diamino hexane reduced cryogel for Cu(II) ion removal from aqueous solutions was investigated. The synthesized adsorbent was characterized by means of FT−IR, 13C NMR, SEM−EDX and compression techniques. Maximum adsorption for Cu(II) ions was obtained at pH 5.5. The impact of several operating parameters such as metal ion concentration, adsorbent dosage, and temperature were elucidated and optimized by central composite design model of response surface methodology. Maximum adsorption capacity was determined as 119.13mg/g at obtained optimum experimental conditions of initial Cu(II) ion concentration (100mg/L), adsorbent dosage (80mg) and temperature (55°C). The isotherm and kinetic data revealed that the Langmuir and pseudo 2nd-order models to be in good agreement with the experimental data. Evaluation of adsorption mechanism by intra−particle diffusion and Boyd model suggested that particle diffusion was the rate limiting step for Cu(II) ion uptake and was mainly due to external mass transport. Thermodynamic parameters Gibbs free energy (ΔG°) and enthalpy (ΔH°) confirmed the spontaneity and endothermicity of the adsorption process. Theoretical calculations suggested that both physisorption and chemisorption were active processes. Performed consecutive four cycles also show that the cryogel is a good alternative with high reusability and cost-friendly properties.

Different influences of nanopore dimension and pH between chlorpheniramine adsorptions on graphene oxide-iron oxide suspension and particle

By synthesizing GO-Fe3O4 nanocomposites (graphene oxide coated with magnetite), this study investigated chlorpheniramine (a widely used pharmaceutical) adsorption on magnetic GO-Fe3O4, with respect to the influences of using the nanocomposite suspension or particles, mass ratios of Fe3O4/GO in the synthesis, pH, and contact time. GO-Fe3O4 was characterized by thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and Brunauer–Emmett–Teller theory. Nano-sized Fe3O4 anchored on GO uniformly, resulting in hybrid structures with well combination between GO and Fe3O4. By fitting to the pseudo 2nd-order model, chlorpheniramine adsorption onto GO-Fe3O4 likely occurred due to a chemical adsorption. The adsorption maximums decreased in the order: GO-Fe3O4 particles>GO-Fe3O4 suspension>activated carbon. With Fe3O4 changing the surface charge of GO-Fe3O4 suspension, pH variation enhanced chlorpheniramine adsorption on GO-Fe3O4 suspension. The GO-Fe3O4 particles exhibited a relatively better but slow chlorpheniramine adsorption. More importantly, additional nanopore volumes and surface areas were created in GO-Fe3O4 particles due to low Fe3O4 contents to more effectively capture and remove chlorpheniramine, as Fe3O4 crystals on the GO surface potentially prevented the compaction of GO sheets. These factors interactively affected and determined the approach of using GO for removing chlorpheniramine or other pharmaceuticals with similar molecular characteristics in wastewater treatment.

The influence of acid treatments over vermiculite based material as adsorbent for cationic textile dyestuffs

The influence of different acid treatments over vermiculite was evaluated. Equilibrium, kinetic and column studies have been conducted. The results showed that vermiculite first treated with nitric acid and then with citric acid has higher adsorption capacity, presenting maximum adsorption capacities in column experiments: for Astrazon Red (AR), 100.8 ± 0.8 mg g−1 and 54 ± 1 mg g−1 for modified and raw material, respectively; for Methylene Blue (MB) 150 ± 4 mg g−1 and 55 ± 2 mg g−1 for modified and raw material, respectively. Materials characterization by X-ray diffraction, UV–vis-diffuse reflectance spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, X-ray fluorescence, N2 adsorption and CEC determination, has been performed. The results suggest the existence of exchange of interlayer cations, leaching of metals from vermiculite's sheets and formation of an amorphous phase in the material. Adsorption follows pseudo 2nd order model kinetics for both dyestuffs and equilibrium occurs accordingly to Langmuir's model for AR and Freundlich's model for MB. In column systems Yan's model is the best fit. The enhanced properties of acid treated vermiculite offer new perspectives for the use of this adsorbent in wastewater treatment.

Phosphate recovery through adsorption assisted precipitation using novel precipitation material developed from building waste: Behavior and mechanism

Phosphate is very important basic material in agricultural and other industrial applications. In present study, phosphate was precipitated and recovered through a tablet precipitation material (TPM) which was developed from solid building waste. The development of TPM provided an alternative for the management of building waste. The results showed that TPM could effectively recover phosphate from aqueous solution; the final precipitates were consisted of hydroxyapatite and brushite. The precipitation recovery process was assisted and drove by adsorption mechanism. The adsorption process concentrated and attracted phosphate that supplied partial phosphate supersaturation surround the surface of TPM and assisted the precipitation process. The equilibrium of removal and recover process could be attained in 60min. The maximum recovery capacity achieved 3.81±0.24mgg−1. In addition, the release of Ca2+ from TPM fitted a pseudo-2nd order model, and the release process was divided into two stages according to the Fick’s law. Totally, TPM developed from building waste exhibited sufficient potential in phosphate recovery.

Copper (II) Removed from Aqueous Solutions by Aminated Bagasse Pith

The paper investigated the heavy metal ions adsorption by bio-adsorbent obtained from modifying bagasse pith. The bagasse pith, a main solid bio-waste from sugar and pulp industry, was treated by epichlorohydrin and diethylenetriamine. The pith before and after modification were analyzed to characterize its structure change by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscope. It shown that numbers of minor fragments cohere to the surface of fibrous bundle of modified pith. The carboxyl groups has been introduced with the change of substitutional groups in aromatic skeletal of lignin on surface of pith. The kinetics and thermo-dynamic properties were studied. The results shown the adsorption process are well described by Langmuir isotherm and pseudo-2nd order model. It is considered that the bagasse pith, a renewable bio- waste, would be modified to treat the waste water polluted by heavy metal in further studies.

Cempedak durian as a potential biosorbent for the removal of Brilliant Green dye from aqueous solution: equilibrium, thermodynamics and kinetics studies.

Cempedak durian peel (CDP) was used to remove Brilliant Green (BG) dye from aqueous solution. The adsorption of BG onto CDP was studied as functions of contact time, pH, temperature, ionic strength and initial concentration. In order to understand the adsorption process and its mechanisms, adsorption isotherm and kinetics models were used. The experiments were done under optimized 2-h contact time and ambient pH. Adsorption study showed that the Langmuir model best fitted with experimental data, and the maximum adsorption capacity was determined as 0.203mmol g(-1) (97.995mg g(-1)). Adsorption kinetics followed the pseudo 2nd order model, and intraparticle diffusion is involved but not as the rate-limiting step while Boyd model suggests that film diffusion might be in control of the adsorption process. Fourier transform infrared (FTIR) analysis showed that OH, C=O, C=C and NH functional groups might be involved in the adsorption of BG onto CDP. Thermodynamic study suggested that the adsorption of BG onto CDP is endothermic with ΔH (o) value of 12kJ mol(-1) and adsorption is feasible. Regeneration of CDP's ability to remove BG was also studied using three different washing solutions. NaOH (0.1M) was not only sufficient to be used to regenerate CDP's ability to remove BG but also improved its adsorption capability.