Increase In Initial Dye Concentration Research Articles

Sonocatalytic and photocatalytic efficiency of transition metal-doped ZnO nanoparticles in the removal of organic dyes from aquatic environments

The present study investigated the efficiency of transition metal-doped ZnO nanoparticles (NPs) in the removal of Direct Blue 71 from aqueous solutions through photocatalytic (UV and visible light) and sonocatalytic processes. The ZnO particles were synthesized and analyzed by the SEM, XRD, FTIR, AFM, DLS, and zeta potential. The reaction conditions were optimized by concerned catalyst (i.e., dopant percentage and catalyst amount), solution pH, catalyst dose and initial dye concentration. The results demonstrated that the Ag-doped ZnO NPs could provide the highest UV light-based photocatalytic efficiency, while the Cu-doped NPs present the greatest sonocatalytic and visible light-based photocatalytic efficiencies. In all processes, the dye removal efficiency was better in acidic pH. Based on the insignificant difference of efficiency over the acidic range of pH, the natural pH of the dye, i.e., 5.6, was considered as the optimal pH value. Also, the increase of dopant percentage enhanced the decolorization efficiency of the catalysts. However, 2.5% dopant amount was selected as the optimal dopant content due to the negligible difference in the decolorization percentages observed using the 2.5 and 5% dopant percentages. Furthermore, the increase of catalyst dose and contact time increased the removal efficiency, while the increase of initial dye concentration resulted in a lower extent of dye decolorization.

Photocatalytic degradation of methylene blue by the use of titanium-doped Calcined Mussel Shells CMS/TiO2

This work deals with the photo-degradation of methylene blue (MB) dye in aqueous medium by the use of Calcined Mussel Shells (CMS) doped with titanium dioxide (TiO2). Experiments were carried out under UV light using a variety of conditions in order to highlight the effect on oxidation process of different operating parameters such as pH, initial concentration of dye, catalyst dosage, TiO2 percentage in CMS, contact time and the presence of H2O2. Obtained results showed that these parameters govern considerably the photo-catalytic treatment efficiency. CMS/40%TiO2 seems the best composition for photo-catalytic degradation of MB and basic pH is necessary to achieve high level of discoloration. The increase of initial dye concentration reduces the efficiency of the photo-catalytic process. However, the addition of H2O2 improves considerably its performance.

Sorption studies of methyl red dye removal using lemon grass (Cymbopogon citratus)

Lemongrass leaf based activated carbon (LGLAC) was prepared using physico-chemical methods for methyl red (MR) dye removal from aqueous solutions. The surface chemistry of LGLAC before adsorption revealed the presence of different functional groups: O-H, C-H, C=O, CH 3 , C=C, N-O, C-O and C-N which were shifted after methyl red dye adsorption. Brunauer-Emmett-Teller surface and mesopore areas are 836.04 m 2 /g and 598.6 04 m 2 /g, whereas, the average pore diameter and total pore volume of LGLAC are 3.62 nm and 0.472 cm 3 /g respectively. Batch adsorption was studied using different parameters: initial dye concentrations (25–500 mg/L), contact time (0–24 h), solution temperature (30–60 °C) and solution pH (2–12). Adsorption of methyl red dye was observed to increase with increase in initial dye concentration, contact time and solution temperature. The methyl red dye adsorption uptake and percentage removal at equilibrium showed that the adsorption process is majorly dependent on the initial dye concentration. Optimum percentage of methyl red dye removed was observed at pH 2. The adsorption process of methyl red dye onto LGLAC was endothermic in nature. Thermodynamic parameters, including entropy change ( Δ S 0 ), enthalpy change ( Δ H 0 ), and Gibbs free energy change ( Δ G 0 ) were evaluated. The adsorption process was endothermic and the mechanism followed a physisorption process.

Removal of Toxic Congo Red Dye Using Water Hyacinth Petiole, an Efficient and Selective Adsorbent

Congo red (CR), one of the major dyes used in the textile mills of Bangladesh has carcinogenic and chronic effect on living system. Removal of CR was done by using water hyacinth petiole (WHP), an efficient and selective adsorbent. Adsorption experiment was performed through batch process at different pH values, dye concentrations, contact times, particle sizes and dosages of adsorbent. A comparable study was carried out using untreated and sodium chlorite treated WHP at different pH values. Equilibrium adsorption was attained after 240 minutes. The highest removal 94.88% was obtained using sodium chlorite treated water hyacinth petiole (SCT-WH) and 94.51% using untreated water hyacinth petiole (UT-WH) at pH 6. Adsorption increased with the increase of initial dye concentration and after a certain time saturation was attained. Adsorption decreased with the increase of particles size (≤ 75and#181;m, ≤ 150and#181;m and ≤ 300and#181;m) and increased with the amount of adsorbent (0.25g, 0.50g and 0.75g). The equilibrium data were best described by the Freundlich isotherm and adsorption kinetics better fitted to pseudo-second-order kinetic model.

A Comparative Efficiency Study of Two Adsorbent Materials to Remove Eosin Y Dye from Aqueous Solutions

This study was done to find a cheap, available and ecofriendly materials that can remove eosin y dye from aqueous solutions by adsorption in this study, two adsorbent materials were used, the shells of fresh water clam (Cabicula fluminea) and walnut shells. To make a comparison between the two adsorbents, five experiments were conducted. First, the effects of the contact time, here the nut shell removed the dye quickly, while the C. flumina need more contact time to remove the dye. Second, the effects of adsorbent weight were examined. The nut shell was very promising and for all used adsorbent weight, the R% ranged from 94.87 to 99.29. However C. fluminea was less effective in removing the dye with R% ranged from 47.59 to 55.39. The third experiment was initial dye concentration. The C. fluminea showed very low ability to remove eosin y , while the nut shell was more effective in removing the dye with R% up to 97.36 and an inverse correlation between the increase of initial dye concentration and R%. The fourth experiment was the effect of pH value of the solution and the adsorbent particles size. The results show that fine particles were more effective than granular particles. Throughout the whole study, the walnut shell was very promising in removing the dye, while the C. fluminea shell was much less effective than the walnut shell.

Photocatalytic studies of electrochemically synthesized polysaccharide-functionalized ZnO nanoparticles

The present work reports the electrochemical synthesis of polysaccharide-functionalized ZnO nanoparticles using sodium hydroxide, starch, and zinc electrodes for the degradation of cationic dye (Rhodamine-B) under sunlight. Physiochemical properties of synthesized sample have been characterized by different techniques such as XRD, TEM, FESEM, EDS, IR, and UV–visible spectroscopic techniques. The influence of various factors such as effect of dye concentration, contact time, amount of photocatalyst, and pH has been studied. The results obtained from the photodegradation study showed that degradation rate of Rhodamine-B dye has been increased with increase of amount of photocatalyst and decreased with increase in initial dye concentration. Furthermore, the kinetics of the degradation has been investigated. It has been found that the photodegradation of Rhodamine-B dye follows pseudo-first-order kinetics and prepared photocatalyst can effectively degrade the cationic dye. Thus, this ecofriendly and efficient photocatalyst can be used for the treatment of dye-contaminated water. This catalyst also showed the antibacterial activity against Bacillus pumilus and Escherichia coli bacterial strains, so the synthesized nanoparticles also have the pharmaceutical properties.

Application of Carbonized Metal–Organic Framework as Efficient Adsorbent of Cationic Dye

Herein, we report study about adsorption kinetics of rhodamine B onto metal organic framework containing cobalt (CoOF). The CoOF can be successfully produced from the reused waste–organic ligands and solvents. The as-prepared material was carbonized and purified prior to testing. The adsorbent was characterized with scanning electron microscopy, Fourier transform infrared spectrophotometer, X-ray diffractometer, thermogravimetric analysis, Raman spectroscope, and N2 adsorption/desorption isotherms. The kinetics of dye adsorption onto structure was examined with the UV–Vis spectrophotometer. Various physiochemical parameters such as initial dye concentration, pH of dye solution, and temperature were investigated in an adsorption technique. The adsorption uptake was found to increase with increase in initial dye concentration. An increase in adsorption capacity was noticed when the solution was changed to basic, optimum conditions obtained at pH 7. The results indicate that along with an increase in the tem...

A Comparative Efficiency Study of Two Adsorbent Materials to Remove Eosin Y Dye from Aqueous Solutions

This study was done to find a cheap, available and ecofriendly materials that can remove eosin y dye from aqueous solutions by adsorption in this study, two adsorbent materials were used, the shells of fresh water clam (Cabicula fluminea) and walnut shells. To make a comparison between the two adsorbents, five experiments were conducted. First, the effects of the contact time, here the nut shell removed the dye quickly, while the C. flumina need more contact time to remove the dye. Second, the effects of adsorbent weight were examined. The nut shell was very promising and for all used adsorbent weight, the R% ranged from 94.87 to 99.29. However C. fluminea was less effective in removing the dye with R% ranged from 47.59 to 55.39. The third experiment was initial dye concentration. The C. fluminea showed very low ability to remove eosin y , while the nut shell was more effective in removing the dye with R% up to 97.36 and an inverse correlation between the increase of initial dye concentration and R%. The fourth experiment was the effect of pH value of the solution and the adsorbent particles size. The results show that fine particles were more effective than granular particles. Throughout the whole study, the walnut shell was very promising in removing the dye, while the C. fluminea shell was much less effective than the walnut shell.

Degradation of reactive orange 16 using a prototype atmospheric-pressure non-thermal plasma reactor

A prototype atmospheric pressure non-thermal corona plasma reactor system is developed and tested for the removal of commercial textile reactive dye from water. The dye can be completely degraded in water by the presented reactor system in the initial concentration range of 10-100 mg dm-3. Dye degradation rate decreases with the increase of initial dye concentration and pulse frequency. The pH of treated solutions decreases with the increase of treatment time and with the decrease of the applied frequency. Solutions electrical conductivity increases with an increase of treatment time and with the decrease of the applied frequency. The decolorization reactions follow the pseudo-first kinetics order. The changes in the treated dye solutions compositions are the consequences of injection of plasma generated reactive species from gas into the liquid through the interfacial zone.

Functionalization of powdered walnut shell with orthophosphoric acid for Congo red dye removal

ABSTRACTThis study investigates the adsorption of Congo red dye on walnut shell powder based activated carbon in batch process (WNAA). Walnut shell powder was carbonized by treating with phosphoric acid (H3PO4), and the adsorbent was characterized using Fourier Transform-Infrared spectrophotometer (FT-IR), Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), and pH point of zero charge (pHpzc), respectively. Operational parameters such as contact time, initial dye concentration, and pH were investigated using batch-adsorption techniques. The adsorption uptake was found to increase with increase in initial dye concentration and contact time. The optimum CR dye uptake was observed at pH 3.12 corresponding to 94.53% removal. Pseudo-first-order, pseudo-second-order, Elovich, and Intraparticle diffusion kinetic models were used to test the adsorption data. The pseudo-second order exhibited the best fit out of the four kinetic models used. Equilibrium data were fitted to the Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherm models. Langmuir model fitted the adsorption data most with maximum monolayer coverage of 40 mg/g. Thermodynamic parameters such as Gibbs free energy, enthalpy, entropy, and the activation energy were determined. It was found that Congo red dye adsorption was spontaneous and endothermic. 0.02M Hydrochloric acid was used to regenerate the adsorbent prepared, and the regenerated adsorbent was used for dye adsorption. Congo red dye adsorption capacity ranged from 90% to 93% at three consecutive times. This study has shown that walnut shell is a good adsorbent in the treatment of Congo red dye from aqueous solutions.

Degradation of Acid Orange 7 by an ultrasound/ZnO-GAC/persulfate process

Abstract Granular activated carbon (GAC) supported ZnO catalyst (ZnO-GAC) was prepared to activate persulfate (PS) for the decolorization of Acid Orange 7 (AO7) in the presence of ultrasonic irradiation (US). The effects of initial pH, PS concentration, catalyst dosage, initial dye concentration, and reaction temperature were investigated. The results showed that the decolorization efficiency increased with the increase of catalyst dosage and temperature, but decreased with the increase of initial dye concentration and initial pH, and the optimal PS concentration for color removal was 0.5 g L−1. Radical quenching tests were performed by using ethanol, tert-butanol and phenol to verify the formation of sulfate radicals and hydroxyl radicals in the US/ZnO-GAC/PS process. Under the optimal conditions, 91.2% of decolorization was achieved and 83.1% of TOC was removed after 60 min treatment. Activated sludge inhibition tests were carried out to monitor the change of toxicity during the treatment of AO7 solution.

Synthesis, Characterization and Reactivity of Nanostructured Zero-Valent Iron Particles for Degradation of Azo Dyes

Nanostructured zero-valent iron (NSZVI) particles were synthesized by the method of ferric ion reduction with sodium borohydride with subsequent drying and passivation at room temperature in technical grade nitrogen. The obtained sample was characterized by means of X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and dynamic light scattering studies. The prepared NSZVI particles represent 100–200[Formula: see text]nm aggregates, which consist of 20–30[Formula: see text]nm iron nanoparticles in zero-valent oxidation state covered by thin oxide shell. The reactivity of the NSZVI sample, as the removal efficiency of refractory azo dyes, was investigated in this study. Two azo dye compounds, namely, orange G and methyl orange, are commonly detected in waste water of textile production. Experimental variables such as NSZVI dosage, initial dye concentration and solution pH were investigated. The kinetic rates of degradation of both dyes by NSZVI increased with the decrease of solution pH from 10 to 3 and with the increase of NSZVI dosage, but decreased with the increase of initial dye concentration. The removal efficiencies achieved for both orange G and methyl orange were higher than 90% after 80[Formula: see text]min of treatment.

Enhanced Adsorptive Removal of Anionic Dyes by using Calcined Zinc Aluminium Layered Double Hydroxide CZA-LDH from Aqueous Solution

Removal of anionic dyes namely Acid Violet-17(AV-17) and Direct Red-7 (DR-7) from aqueous solution were investigated by calcined zinc aluminium layered double hydroxide (CZA-LDH). Batch adsorption studies were carried out by varying the parameters such as contact time, adsorbent dose, initial dye concentration, temperature and pH. The equilibrium adsorption capacity of AV-17 (adsorbent dose 0.5g/L) and DR-7(adsorbent dose 0.125g/L) dyes were increased from 48.08 mg/g to 172.55 mg/g and 200 mg/g to 683.33 mg/g respectively with increase of initial dye concentration from 25 mg/L to 100 mg/L at 30°C. Similarly the percentage of dye removal was decreased from 100% to 85.42% and 96.15% to 86.27% for DR-7 and AV-17 respectively with increase of initial dye concentration from 25 mg/L to 100 mg/L. The adsorption kinetics of both the anionic dyes AV-17 and DR- 7 by CZA-LDH followed the pseudo second order kinetic model with high correlation coefficient values (R2) than the pseudo first order. The experimental data were well fitted with Freundlich isotherm model rather than Langmuir model. The adsorption equilibrium was more favourable at acidic pH than alkaline pH for both dyes. The thermodynamic parameters like ΔGo and ΔHo calculated for AV-17 and DR-7 revealed that the adsorption process is spontaneous and endothermic in nature. The XRD pattern of CZA-LDH before and after the adsorption of AV-17 and DR-7 proved the intercalation of anionic dyes between the layers with memory effect by the reconstruction of its original layered structure. This was further evidenced by slight increase in the interlayer distance. The adsorption processes were further supported by Langmuir dimensionless separation factor RL and n value of the Freundlich Equation. Thermal regeneration and reusability of CZA-LDH was performed for the removal of AV-17 & DR-7. The recycling and reusability for the dye removal up to second cycle for both anionic dyes were remarkable and suggested that the CZA-LDH was an effective adsorbent for the removal of anionic dyes AV-17 and DR-7 from aqueous solution.

Bioremediation of red azo dye from aqueous solutions by Aspergillus niger strain isolated from textile wastewater

Biological treatment with fungi has proven to be effective in removing color from textile wastewater containing organic contaminants as an eco-friendly established technique. The main purpose of this research is to remove red azo dye from aqueous solution using Aspergillus niger strain. In a direct application, fungal biomass was tested for the decolorization under different environmental conditions such as contact time, bio-sorbent dosage, pH, agitation speed, and initial dye concentration. The highest azo dye removal efficiency was obtained at the pH 9, agitation speed 250, biosorbent dose 3.5g, and contact time 120min. The removal efficiency decreased with the increase in initial dye concentration. Freundlich isotherm model was best fitted when compared to Langmuir isotherm model, as it has a higher correlation coefficient (R2=0.977). At dye concentration 1000mg/L, the net dry biomass of A. niger increased from 0.18 to 0.58g after seven days of incubation at 28±1°C indicating the high biodegradability of fungal strain. Examination with Scanning Electron Microscope (SEM) showed high affinity of A. niger to the direct red azo dye. The statistical analysis using the interactive response surface methodology (IRSM) technique showed that the dye removal efficiency depends mainly on the contact time, pH, and biomass dosage. In contrast, the effect of initial dye concentration and agitation speed on the dye removal was minor.

Ultrasound-assisted removal of Acid Red 17 using nanosized Fe3O4-loaded coffee waste hydrochar

The Fe3O4-loaded coffee waste hydrochar (Fe3O4-CHC) was synthesized using a simple precipitation method. The as-prepared adsorbent was characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FT-IR). The EDX analysis indicated the presence of Fe in the structure of Fe3O4-CHC. The specific surface area of hydrochar increased from 17.2 to 34.7m2/g after loading of Fe3O4 nanoparticles onto it. The prepared Fe3O4-CHC was used for removal of Acid Red 17 (AR17) through ultrasound-assisted process. The decolorization efficiency decreased from 100 to 74% with the increase in initial dye concentration and from 100 to 91 and 85% in the presence of NaCl and Na2SO4, respectively. The synthesized Fe3O4-CHC exhibited good stability in the repeated adsorption-desorption cycles. The high correlation coefficient (R2=0.997) obtained from Langmuir model indicated that physical and monolayer adsorption of dye molecules occurred on the Fe3O4-CHC surface. Furthermore, the by-products generated through the degradation of AR17 was identified by gas chromatography–mass spectrometry analysis.

Adsorption removal of Methylene Blue (MB) dye from aqueous solution by bio-char prepared from Eucalyptus sheathiana bark: kinetic, equilibrium, mechanism, thermodynamic and process design

Eucalyptus bark (EB) materials-based bio-char adsorbent was synthesised and characterised using SEM-EDS, BET and CHN analyser. The adsorbent surface functional groups were determined by FT-IR analyser. Various textural characteristics such as BET surface area, pore size, bulk density, point of zero charge were also determined. The adsorption potential of these bio-char for the removal of cationic dye Methylene Blue (MB) from aqueous solution was studied. The effects of various temperature profiles on the production of EB bio-char were studied and the most efficient temperature profile was identified at 500°C. Batch adsorption kinetic study showed that the amount of dye adsorbed qt (mg/g) depends on various physicochemical process parameters such as initial solution pH, dye concentration, temperature, adsorbent dose, salt concentration and presence of SDS surfactant. It was found that the extent of MB dye adsorption by EB bio-char increased with the increase of initial dye concentration, contact time, temperature, SDS surfactant concentration and solution pH, but decreased with the increase of adsorbent dose and salt concentration. The optimum adsorption conditions were found at the initial dye concentration of 100 mg/L, initial solution pH of 11.3, adsorbent dose of 10 mg and solution temperature of 55°C. Furthermore, pseudo-first-order, pseudo-second-order and intra-particle diffusion models were fitted to examine the adsorption kinetics and mechanism of adsorption. Equilibrium data were best represented by Langmuir isotherm model and gives a monolayer effective adsorption capacity of bio-char which is comparative to other adsorbents including commercial activated carbon. Thermodynamic parameters suggested that the adsorption was an endothermic, spontaneous and physical in nature. Furthermore, a single-stage batch adsorber design for the MB dye onto EB bio-char particles were presented based on the Langmuir isotherm model equation. These results indicated EB biomass as good and cheap precursor for the production of an effective and environmental friendly bio-char adsorbent.

Surface modified spinel cobalt ferrite nanoparticles for cationic dye removal: Kinetics and thermodynamics studies

Present study is an endeavour to explore adsorption potential cobalt ferrite nanoparticles which were synthesised by combustion method and its surface modification was done by a SDS surfactant to make it suitable for the removal of cationic dye. Characterization was carried through FTIR, SEM and XRD analysis. Batch adsorption studies were carried out for removal of crystal violet cationic dye by SDS coated cobalt ferrite. Various parameters like initial concentration (50–300mg/L), effect of contact time, adsorbent dose (0.1–0.5 gm/50mL), and pH (2–9) were studied at constant temperature. Equilibrium time for the adsorption process was found to be 2h. Adsorption percentage of dye increased with an increase in the adsorbent dose and amount of adsorption increased with an increase in initial dye concentration. Initial pH in the basic region exhibited better results as compared to acidic pH. Langmuir adsorption isotherm fitted better than Temkin followed by Freundlich and Dubinin-Raduskevich adsorption isotherms. Monolayer adsorption capacity was found to be 105mg/g which is comparable to other reported adsorbents. Adsorption followed Lagergren pseudo second order kinetics model better than Lagergren pseudo first order and Elovich models. Adsorption studies conducted at different temperatures (301–313K) indicated rise in adsorption with the increase in temperature. This implied that sorption phenomenon was endothermic in this case. Data was fitted to Van’t Hoff equation to study thermodynamics. Value of ΔH° was in the range of 23–88kJ/mol for different concentration which indicated that mechanism of adsorption was complex comprising of both physical and chemical adsorption.

Removal of Acid Alizarin Black Dye from Aqueous Solution by Adsorption Using Zinc Oxide

The adsorption of Acid Alizarin Black (AAB) dye (C.I. 21725) on zinc oxide was investigated in this study. The adsorption was carried out under different operating conditions. The operating conditions were contact time, adsorbent dosage (10, 30, 50, 70 and 100 mg), initial dye concentration (10, 20, 30, 40, 50, 60 and 70 mg/L), the pH of the solution (2, 4, 6, 7, 8, 10 and 12) and temperature (20, 30, 40, 50 and 60°C). The remo val percentage of dye on ZnO decreases from 67% to 54% with increase in initial dye concentration from 10 to 70 mg/L, respectively. It was found that the increasing of ZnO dosage enhanced the dye removal. The increasing of temperature insignificantly enhanced the removal of dye. The study reports that the best pH of solution for the adsorption of AAB on ZnO were 7 and 8. The adsorption data have been analysed using Langmuir, Freundlich and Temkin. It is indicated that the adsorption of dye onto ZnO was endothermic. The uptake process of AAB obeyed the pseudo second order kinetic expression.

Decolourization of Rhodamine B from aqueous solution by electrochemical oxidation using graphite electrodes

This study investigated the colour removal efficiency of Rhodamine B (RhB) by electrochemical oxidation. The influences of various operating variables such as current density (from 5 to 25 mA/cm2), initial concentration of dye solution (from 50 to 250 mg/L), initial pH of solution (3, 5, 7, 9), the stirrer speed (150–300 rpm) and the concentration of electrolytes (0.025–0.10 M NaCl) on removal efficiency were explored in a batch mode treatment to achieve a higher removal capacity. The results obtained with synthetic wastewater revealed that the most effective removal of dye could be achieved when the pH was kept neutral. The results showed that the colour removal increases with the increase in applied current density, NaCl concentration, while it was found to decrease with the increase in initial dye concentration. The complete (100%) colour removal has been achieved under the optimal experimental conditions such as NaCl concentration of 0.05 M, applied current density of 15 mA/cm2, initial pH 7.0, stirrer speed of 200 rpm and electrolysis time of 40 min. The result of UV–vis spectrum analysis confirms the removal of colour from RhB aqueous solution at the short treatment time. In addition, the increase of current intensity, in the range of 0.6–2.0 A, enhanced the treatment rate. The method was found to be highly efficient and relatively fast compared to conventional treatment techniques.

English

Chlorophyta hydrodictyon africanum was immobilized on a silica gel matrix to improve its mechanical properties. The algae-silica gel adsorbent was used for batch sorption studies of a cationic dye, methylene blue (MB). Optimum adsorption was obtained with a dosage of 0.8 g bio sorbent. Results from sorption studies show that 124.11 mg·g-1 of MB could be adsorbed at an optimum pH of 8 and immobilization of 300 mg per gram silica. Maximum immobilization was 400 mg biomass per gram silica. Sorption capacity increased with an increase in initial dye concentration and reached equilibrium within 30 min. Three models were used to simulate kinetic data and the pseudo–second order model gave a better fit with R2 greater than 0.98 in all cases. Equilibrium studies revealed that the adsorption of MB followed Freundlich isotherm (R2=1.00). Key words: Adsorbent, algae, Langmuir model, Freundlich isotherm.