Biosorption of Cd(II) and Pb(II) onto brown seaweed, Lobophora variegata (Lamouroux): kinetic and equilibrium studies

The present work deals with the biosorption performance of raw and chemically modified biomass of the brown seaweed Lobophora variegata for removal of Cd(II) and Pb(II) from aqueous solution. The biosorption capacity was significantly altered by pH of the solution delineating that the higher the pH, the higher the Cd(II) and Pb(II) removal. Kinetic and isotherm experiments were carried out at the optimal pH 5.0. The metal removal rates were conspicuously rapid wherein 90% of the total sorption occurred within 90 min. Biomass treated with CaCl₂ demonstrated the highest potential for the sorption of the metal ions with the maximum uptake capacities i.e. 1.71 and 1.79 mmol g⁻¹ for Cd(II) and Pb(II), respectively. Kinetic data were satisfactorily manifested by a pseudo-second order chemical sorption process. The process mechanism consisting of both surface adsorption and pore diffusion was found to be complex. The sorption data have been analyzed and fitted to sorption isotherm of the Freundlich, Langmuir, and Redlich–Peterson models. The regression coefficient for both Langmuir and Redlich–Peterson isotherms were higher than those secured for Freundlich isotherm implying that the biosorption system is possibly monolayer coverage of the L. variegata surface by the cadmium and lead ions. FT-IR studies revealed that Cd(II) and Pb(II) binding to L. variegata occurred primarily through biomass carboxyl groups accompanied by momentous interactions of the biomass amino and amide groups. In this study, we have observed that L. variegata had maximum biosorption capacity for Cd(II) and Pb(II) reported so far for any marine algae. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Removal of cadmium(II) ion from aqueous system by dry biomass, immobilized live and heat-inactivated Oscillatoria sp. H1 isolated from freshwater (Mogan Lake)

Oscillatoria sp. H1 (Cyanobacteria, microalgae) isolated from Mogan Lake was used for the removal of cadmium ions from aqueous solutions as its dry biomass, alive and heat-inactivated immobilized form on Ca-alginate. Particularly, the effect of physicochemical parameters like pH, initial concentration and contact time were investigated. The sorption of Cd(II) ions on the sorbent used was examined for the cadmium concentrations within the range of 25-250 mg/L. The biosorption of Cd(II) increased as the initial concentration of Cd(II) ions increased in the medium up to 100 mg/L. Maximum biosorption capacities for plain alginate beads, dry biomass, immobilized live Oscillatoria sp. H1 and immobilized heat-inactivated Oscillatoria sp. H1 were 21.2, 30.1, 32.2 and 27.5 mg/g, respectively. Biosorption equilibrium was established in about 1 h for the biosorption processes. The biosorption was well described by Langmuir and Freundlich adsorption isotherms. Maximum adsorption was observed at pH 6.0. The alginate-algae beads could be regenerated using 50 mL of 0.1 mol/L HCl solution with about 85% recovery.     

Biosorptive removal of cadmium from contaminated groundwater and industrial effluents

The cadmium removing capacity of a biosorbent Calotropis procera, a perennial wild plant, is reported here. The biomass was found to possess high uptake capacity of Cd(II). Adsorption was pH dependent and the maximum removal was obtained at two different pH i.e. pH 5.0 and 8.0. Maximum biosorption capacity in batch and column mode was found to be 40 and 50.5 mg/g. The adsorption equilibrium (> or =90% removal) was attained within 5 min irrespective of the cadmium ion concentration. Interfering ions viz. Zn(II), As(III), Fe(II), Ni(II) interfered only when their concentration was higher than the equimolar ratio. The Freundlich isotherm best explained the adsorption, yet the monolayer adsorption was also noted at lower concentrations of Cd(II). The FTIR analysis indicates the involvement of hydroxyl (-OH), alkanes (-CH), nitrite (-NO(2)), and carboxyl group (-COO) chelates in metal binding. The complete desorption of the cadmium was achieved by 0.1M H(2)SO(4) and 0.1M HCl. The C. procera based Cd(II) removal technology appears feasible.     

Biosorption of cadmium and chromium in duckweed Wolffia globosa

The biosorption of cadmium (Cd) and chromium (Cr) by using dried Wolffia globosa biomass were investigated using batch technique. The effects of concentration and pH solution on the adsorption isotherm were measured by determining the adsorption isotherm at initial metal concentrations from 10 to 400 mg/L and pH 4 to 7 for Cd, and pH 1.5 to 6 for Cr. The adsorption equilibria were found to follow Langmuir models. The maximum adsorption capacity (Xm) at pH 7 in W. globosa-Cd system was estimated to be 80.7 mg/g, while the maximum removal achieved at pH 4, pH 5, and pH 6 were 35.1, 48.8, and 65.4 mg/g, respectively. The Xm at pH 1.5 in W. globosa--Cr system was estimated to be 73.5 mg/g, while the maximum removal achieved at pH 3, pH 5, and pH 6 were 47.4, 33.1, and 12.9 mg/g, respectively. The effects of contact times on Cd and Cr sorption indicated that they were absorbed rapidly and more efficiently at lower concentrations.     

Congo red adsorption from aqueous solutions by using chitosan hydrogel beads impregnated with nonionic or anionic surfactant

The adsorption performance of CS beads impregnated with triton X-100 (TX-100) as a nonionic surfactant and sodium dodecyl sulfate (SDS) as an anionic surfactant was investigated for the removal of anionic dye (congo red) from aqueous solution. While the adsorption capacity of CS/TX-100 beads was enhanced at all concentrations of TX-100 (0.005–0.1%), the increase in the concentration of SDS above 0.01% in the CS/SDS beads gradually reduced the adsorption capacity of the beads. Equilibrium adsorption isotherm data indicated a good fit to the Sips isotherm model and a heterogeneous adsorption process. The Sips maximum adsorption capacity in dry weight of the CS/TX-100 beads was 378.79 mg/g and 318.47 mg/g for the CS/SDS beads, higher than the 223.25 mg/g of the CS beads. Modification of CS beads by impregnation with nonionic surfactant, or even anionic surfactant, at low concentrations is a possible way to enhance adsorption of anionic dye.     

Application of Poly 1,8‐diaminonaphthalene/multiwalled carbon nanotubes‐COOH hybrid material as an efficient sorbent for trace determination of cadmium and lead ions in water samples

Poly 1,8‐diaminonaphthalene/multiwalled carbon nanotubes‐COOH hybrid material as an effective sorbents in solid phase extraction has been developed for the separation and preconcentration of Cd(II) and Pb(II) at trace levels in environmental water samples. The results indicate that the novel nanocomposite show a high affinity for these heavy metals due to the presence of several good extractive sites, which are introduced to the synthesized nanocomposite The maximum adsorption capacity of the synthesized sorbent for cadmium and lead ions was found to be 101.2 and 175.2 mg g^?1, respectively. The detection limits of this method were 0.09 and 0.7 ng ml^?1 for Cd(II) and Pb(II), respectively. Copyright © 2014 John Wiley & Sons, Ltd.     

Alginate coated loofa sponge discs for the removal of cadmium from aqueous solutions

A biosorbent was prepared by coating the fibrous network of loofa sponge (Luffa cylindrica) with a thin film of calcium alginate. Alginate-coated loofa sponge removed Cd(II) rapidly, reaching equilibrium loading of 124 mg g(-1) in 30 min. Seventy % of equilibrium uptake was achieved in 10 min. In contrast, it took 240 min for alginate beads to reach a loading equilibrium of 88 mg g(-1) under identical conditions. The biosorption behaviour followed the Langmuir adsorption isotherm and the ACLS biosorbent was shown to be highly effective in removing Cd(II) from a 10 mg l(-1) solution in a continuous flow fixed-bed column bioreactor.     

Sorption of Cu(II) and Cd(II) by extracellular polymeric substances (EPS) from Aspergillus fumigatus

Sorption of Cu(II) and Cd(II) onto the extracellular polymeric substances (EPS) produced by Aspergillus fumigatus was investigated for the initial pH of the solution, EPS concentrations, contact time, NaCl concentration, initial metal ion concentration and the presence of other ions in the solution. The results showed that the adsorption of metal ions was significantly affected by pH, EPS concentrations, initial metal concentration, NaCl concentration and co-ions. The sorption of Cu(II) and Cd(II) increased with increasing pH and initial metal ion concentration but decreased with an increase in the NaCl concentration. The maximum sorption capacities of A. fumigatus EPS calculated from the Langmuir model were 40 mg g⁻¹ EPS and 85.5 mg g⁻¹ EPS for Cu(II) and Cd(II), respectively. The binary metal sorption experiments showed a selective metal binding affinity in the order of Cu(II) > Pb(II) > Cd(II). Both the Freundlich and Langmuir adsorption models described the sorption of Cu(II) and Cd(II) by the EPS of A. fumigatus adequately. Fourier transform infrared spectroscopy (FTIR) analysis revealed that carboxyl, amide and hydroxyl functional groups were mainly correlated with the sorption of Cu(II) and Cd(II). Energy dispersive X-ray (EDX) system analysis revealed that the ion-exchange was an important mechanism involved in the Cu(II) and Cd(II) sorption process taking place on EPS.     

Synthesis of γ-cyclodextrin/chitosan composites for the efficient removal of Cd(II) from aqueous solution

The synthesis of chitosan-graft-γ-cyclodextrin (Ch-g-γ-CD) using persulfate/ascorbic acid redox system was done and characterized by FTIR, XRD, TGA and SEM/EDX. The optimum yield of the copolymer was obtained using 16 × 10⁻³ M γ-cyclodextrins (γ-CD), 2.8 × 10⁻² M ascorbic acid (AA), 1.8 × 10⁻² M K₂S₂O₈ and 0.1 g chitosan in 25 mL of 2% aqueous formic acid at 45 ± 0.2 °C. The highest percent grafting samples were evaluated for cadmium metal ion (Cd(II)) removal from the aqueous solutions where the sorption capacities were found proportional to the grafting extent. The sorption was pH and concentration dependent where, pH = 8.5 was found to be the optimum value. The adsorption data were modeled using Langmuir and Freundlich isotherms. The equilibrium data followed the Langmuir isotherm model with maximum sorption capacity of 833.33 mg/g. The influence of electrolytes, sodium chloride (NaCl) and sodium sulphate (Na₂SO₄) on Cd(II) uptake was also studied. Desorption of the cadmium loaded Ch-g-γ-CD was accomplished with 0.01 N H₂SO₄. The adsorbent exhibited high reusability and could be successfully recycled for nine cycles where in the ninth cycle 27% adsorption was feasible.     

Biosorption of lead, cadmium, and zinc by Citrobacter strain MCM B-181: characterization studies

The biosorption process for removal of lead, cadmium, and zinc by Citrobacter strain MCM B-181, a laboratory isolate, was characterized. Effects of environmental factors and growth conditions on metal uptake capacity were studied. Pretreatment of biomass with chemical agents increased cadmium sorption efficiency; however, there was no significant enhancement in lead and zinc sorption capacity. Metal sorption by Citrobacter strain MCM B-181 was found to be influenced by the pH of the solution, initial metal concentration, biomass concentration, and type of growth medium. The metal sorption process was not affected by the age of the culture or change in temperature. Equilibrium metal sorption was found to fit the Langmuir adsorption model. Kinetic studies showed that metal uptake by Citrobacter strain MCM B-181 was a fast process, requiring <20 min to achieve >90% adsorption efficiency. The presence of cations reduced lead, zinc, and cadmium sorption to the extent of 11. 8%, 84.3%, and 33.4%, respectively. When biomass was exposed to multimetal solutions, metals were adsorbed in the order Co2+ < Ni2+ < Cd2+ < Cu2+ < Zn2+ < Pb2+. Among various anions tested, only phosphate and citrate were found to hamper metal sorption capacity of cells. Biosorbent beads prepared by immobilizing the Citrobacter biomass in polysulfone matrix exhibited high metal loading capacities. A new mathematical model used for batch kinetic studies was found to be highly useful in prediction of experimentally obtained metal concentration profiles as a function of time. Metal desorption studies indicated that Citrobacter beads could, in principle, be regenerated and reused in adsorption-desorption cycles. In an expanded scale trial, biosorbent beads were found to be useful in removal/recovery of metals such as lead from industrial wastewaters.     

Adsorption and Desorption of Nickel(II) Ions from Aqueous Solution by a Lignocellulose/Montmorillonite Nanocomposite

A new and inexpensive lignocellulose/montmorillonite (LNC/MMT) nanocomposite was prepared by a chemical intercalation of LNC into MMT and was subsequently investigated as an adsorbent in batch systems for the adsorption-desorption of Ni(II) ions in an aqueous solution. The optimum conditions for the Ni(II) ion adsorption capacity of the LNC/MMT nanocomposite were studied in detail by varying parameters such as the initial Ni(II) concentration, the solution pH value, the adsorption temperature and time. The results indicated that the maximum adsorption capacity of Ni(II) reached 94.86 mg/g at an initial Ni(II) concentration of 0.0032 mol/L, a solution pH of 6.8, an adsorption temperature of 70°C, and adsorption time of 40 min. The represented adsorption kinetics model exhibited good agreement between the experimental data and the pseudo-second-order kinetic model. The Langmuir isotherm equation best fit the experimental data. The structure of the LNC/MMT nanocomposite was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), whereas the adsorption mechanism was discussed in combination with the results obtained from scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier-transform infrared spectroscopy analyses (FTIR). The desorption capacity of the LNC/MMT nanocomposite depended on parameters such as HNO₃ concentration, desorption temperature, and desorption time. The satisfactory desorption capacity of 81.34 mg/g was obtained at a HNO₃ concentration, desorption temperature, and desorption time of 0.2 mol/L, 60 ºC, and 30 min, respectively. The regeneration studies showed that the adsorption capacity of the LNC/MMT nanocomposite was consistent for five cycles without any appreciable loss in the batch process and confirmed that the LNC/MMT nanocomposite was reusable. The overall study revealed that the LNC/MMT nanocomposite functioned as an effective adsorbent in the detoxification of Ni(II)-contaminated wastewater.     

Immobilization of blue green microalgae on loofa sponge to biosorb cadmium in repeated shake flask batch and continuous flow fixed bed column reactor system

Summary An indigenous strain of blue green microalga, Synechococcus sp., isolated from wastewater, was immobilized onto loofa sponge discs and investigated as a potential biosorbent for the removal of cadmium from aqueous solutions. Immobilization has enhanced the sorption of cadmium and an increase of biosorption (21%) at equilibrium was noted as compared to free biomass. The kinetics of cadmium biosorption was extremely rapid, with (96%) of adsorption within the first 5 min and equilibrium reached at 15 min. Increasing initial pH or initial cadmium concentration resulted in an increase in cadmium uptake. The maximum biosorption capacity of free and loofa immobilized biomass of Synechococcus sp. was found to be 47.73 and 57.76 mg g⁻¹ biomass respectively. The biosorption equilibrium was well described by Langmuir adsorption isotherm model. The biosorbed cadmium was desorbed by washing the immobilized biomass with dilute HCl (0.1 M) and desorbed biomass was reused in five biosorption–desorption cycles without an apparent decrease in its metal biosorption capacity. The metal removing capacity of loofa immobilized biomass was also tested in a continuous flow fixed-bed column bioreactor and was found to be highly effective in removing cadmium from aqueous solution. The results suggested that the loofa sponge-immobilized biomass of Synechococcus sp. could be used as a biosorbent for an efficient removal of heavy metal ions from aqueous solution.     

Low cost bio-sorbent 'wheat bran' for the removal of cadmium from wastewater: kinetic and equilibrium studies

Novel bio-sorbent wheat bran has been successfully utilized for the removal of cadmium(II) from wastewater. The maximum removal of cadmium(II) was found to be 87.15% at pH 8.6, initial Cd(II) concentration of 12.5 mg l-1 and temperature of 20 degrees C. The effect of different parameters such as contact time, adsorbate concentration, pH of the medium and temperature were investigated. Dynamics of the sorption process were studied and the values of rate constant of adsorption, rate constant of intraparticle diffusion and mass transfer coefficient were calculated. Different thermodynamic parameters viz., changes in standard free energy, enthalpy and entropy have also been evaluated and it has been found that the reaction was spontaneous and exothermic in nature. The applicability of Langmuir isotherm showed of monolayer coverage of the adsorbate on the surface of adsorbent. A generalized empirical model was proposed for the kinetics at different initial concentrations.     

Synthesized β-cyclodextrin modified graphene oxide (β-CD-GO) composite for adsorption of cadmium and their toxicity profile in cervical cancer (HeLa) cell lines

In the current study, a composite material was constructed using β-cyclodextrin/graphene oxide (β-CD-GO) and was then applied for the purpose of eliminating cadmium (Cd) from aqueous solution. The synthesized β-CD-GO composite material was then subjected to characterization using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The batch study was conducted for the purpose of removing Cd(II). The results of the study revealed that the β-CD-GO composite material demonstrated a high adsorption capacity of 196 mg/g of Cd(II) at pH 7.0. Further, the adsorption of Cd(II) on the β-CD-GO followed pseudo second-order kinetics and equilibrium adsorption data, which fitted well to the Langmuir isotherm model. The evaluation of the toxicity of the synthesized β-CD-GO composite material was done by the examination of the cervical cancer (HeLa) cell lines. Increasing concentration of β-CD-GO composite material (50 μg to 200 μg) leads to a decline in the percentage of cell viability as from 74 % to 25 %. This study has suggested that the β-CD-GO could play an efficient and beneficial source of the adsorbent for the purpose of eliminating Cd(II) from aqueous solution.     

Continuous fixed-bed column study and adsorption modeling: Removal of cadmium (II) and lead (II) ions in aqueous solution by dead calcareous skeletons

The sorption of Cd(II) and Pb(II) ions was conducted in a continuous fixed-bed column by using dead calcareous skeletons (CS). The column performances were evaluated by varying the adsorbent bed height, influent flow rate and metals initial concentration. The breakthrough curve for the bed height indicated that a longer bed column prolonged the life span of the column with a maximum capacity of 26.447 and 38.460 mg/g for the Cd(II) and Pb(II) column, respectively. The increased flow rate and initial concentration caused the column exhaustion time to occur earlier. The experimental column data were also expressed in column adsorption models, namely, the Thomas, Yoon–Nelson and Adam–Bohart models. The Thomas model fitted well with the Cd(II) data with the correlated curve (r² > 0.9). The Yoon–Nelson model was selected to predict the 50% breakthrough time achieved by the column system and provided the estimated breakthrough time for the columns that were not exhausted during the operation. The Adam–Bohart model was applicable for the initial part of adsorption with the saturation concentration data at the equilibrium. The saturation index of aragonite and calcite depicted that dissolution of calcium occurred in the aqueous solution. The experimental and theoretical data were correlated with a significant relationship trend (p < 0.01), which showed that the trend of experimental data fit well with the modeling trend. The trends of both the experimental and theoretical data were strongly and significantly correlated due to involving the column parameters and the components of CS.     

Sorption of cadmium from aqueous solution using pretreated rice husk

The sorption of Cd(II) from aqueous solution by rice husk, a surplus agricultural byproduct was investigated. Some simple and low-cost chemical modifications resulted in increasing the sorption capacity of raw rice husk (RRH) from 8.58 mg/g to 11.12, 20.24, 16.18 mg/g and reducing the equilibrium time from 10 h of RRH to 2, 4 and 1 h for epichlorohydrin treated rice husk (ERH), NaOH treated rice husk (NRH), sodium bicarbonate treated rice husk (NCRH), respectively. The effect of pH, sorption kinetics and isotherms were studied in batch experiments. Good correlation coefficient was obtained for pseudo second-order kinetic model, which agreed with chemisorption as the rate-limiting mechanism. Sorption isotherm test showed that equilibrium sorption data were better represented by Langmuir model than the Freundlich model. The highly efficient low cost and the rapid uptake of Cd(II) by NCRH indicated that it could be an excellent alternative for the removal of heavy metal by sorption process.     

Cadmium removal from water environment by a fungus Volveriella volvacea

Biosorption technique was used for removal of cadmium under different conditions from water environment using a biosorbent, Volveriella volvaceas, locally growing fruit bodies of mushroom. Effects of different parameters like pH, sorbent concentration, ionic strength on the removal efficiency of cadmium by V. volvacea were carried out in continuation with adsorption kinetics and equilibrium isotherm experiments. From the kinetics studies it was found that nearly 95% of the total cadmium removal was achieved from cadmium spiked distilled water within first 15 minutes. Isotherm data was best fitted to linearised Langmuir equation and the sorption capacity was found to be varying from 9.13 to 9.33 mg/g for different sizes of sorbent. The uptake of cadmium(II) is a function of pH of the solution and increases with the increasing pH. Increasing ionic strength and the presence of soluble complexing agents such as ethylene diamine tetraacetic acid (EDTA) decrease the sorption of cadmium (II). The presence of other diavalent cations like calcium and magnesium impedes the uptake of cadmium (II). The presence of chloride ion has no significant effect on cadmium (II) removal. The spent biosorbent can effectively be regenerated with acid and can then be reused.The present work was carried out by the financial support in terms of fellowship under the cultural exchange programme of the Indo-Bangladesh government. Special thanks to the Director, Bangladesh Institute of Technology, Dhaka, Bangladesh, for providing leave, which enabled the author in carrying out the research work.     

Equilibrium and kinetics studies of adsorption of copper (II) on chitosan and chitosan/PVA beads

The adsorption of Cu(II) ions from aqueous solution by chitosan and chitosan/PVA beads was studied in a batch adsorption system. Chitosan solution was blended with poly(vinyl alcohol) (PVA) in order to obtain sorbents that are insoluble in aqueous acidic and basic solution. The adsorption capacities and rates of Cu(II) ions onto chitosan and chitosan/PVA beads were evaluated. The Langmuir, Freundlich and BET adsorption models were applied to describe the isotherms and isotherm constants. Adsorption isothermal data could be well interpreted by the Langmuir model. The kinetic experimental data properly correlated with the second-order kinetic model, which indicates that the chemical sorption is the rate-limiting step. The Cu(II) ions can be removed from the chitosan and chitosan/PVA beads rapidly by treatment with an aqueous EDTA solution. Results also showed that chitosan and chitosan/PVA beads are favourable adsorbers.     

Enhanced biosorption of mercury(II) and cadmium(II) by cold-induced hydrophobic exobiopolymer secreted from the psychrotroph <Emphasis Type="Italic">Pseudomonas fluorescens</Emphasis> BM07

The cells of psychrotrophic Pseudomonas fluorescens BM07 were found to secrete large amounts of exobiopolymer (EBP) composed of mainly hydrophobic (water insoluble) polypeptide(s) (as contain approximately 50 mol% hydrophobic amino acids, lacking cysteine residue) when grown on fructose containing limited M1 medium at the temperatures as low as 0-10 degrees C but trace amount at high (30 degrees C, optimum growth) temperature. Two types of nonliving BM07 cells (i.e., cells grown at 30 degrees C and 10 degrees C) as well as the freeze-dried EBP were compared for biosorption of mercury (Hg(II)) and cadmium (Cd(II)). The optimum adsorption pH was found 7 for Hg(II) but 6 for Cd(II), irrespective of the type of biomass. Equilibrium adsorption data well fitted the Langmuir adsorption model. The maximum adsorption (Q (max)) was 72.3, 97.4, and 286.2 mg Hg(II)/g dry biomass and 18.9, 27.0, and 61.5 mg Cd(II)/g dry biomass for cells grown at 30 degrees C and 10 degrees C and EBP, respectively, indicating major contribution of heavy metal adsorption by cold-induced EBP. Mercury(II) binding induced a significant shift of infrared (IR) amide I and II absorption of EBP whereas cadmium(II) binding showed only a very little shift. These IR shifts demonstrate that mercury(II) and cadmium(II) might have different binding sites in EBP, which was supported by X-ray diffraction and differential scanning calorimetric analysis and sorption results of chemically modified biomasses. This study implies that the psychrotrophs like BM07 strain may play an important role in the bioremediation of heavy metals in the temperate regions especially in the inactive cold season.     

Removal and recovery of Cu(II) and Zn(II) using immobilized Mentha arvensis distillation waste biomass

The potential use of the immobilized Mentha arvensis distillation waste (IMADW) biomass for removal and recovery of Cu(II) and Zn(II) from aqueous was evaluated in the present study. Biosorption capacity of Cu(II) and Zn(II) on IMADW increased with increase in pH reaching a maximum at 5 for Cu(II) and 6 for Zn(II). The equilibrium sorption data agreed well with Langmuir isotherm model and pseudo-second-order kinetic model in batch mode. Cu(II) and Zn(II) uptake by IMADW was best described by pseudo-first-order kinetic model in continuous mode. Maximum Cu(II) and Zn(II) uptake by IMADW was 104.48 and 107.75 mg/g, respectively. Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were also carried out to investigate functional groups and surface changes of biomass. The results showed that IMADW biomass is a potential biomaterial to remove Cu(II) and Zn(II) ions with a high biosorption capacity from aqueous solutions.