Synthesis of activated carbon from spent tea leaves for aspirin removal

Adsorption capacity of activated carbon prepared from spent tea leaves(STL-AC) for the removal of aspirin from aqueous solution was investigated in this study. Preliminary studies have shown that treatment with phosphoric acid(H_3PO_4) increased removal efficiency of STL-AC. Characterizations on STL-AC revealed excellent textural properties(1200 m~2·g~(-1), 51% mesoporosity), as well as distinctive surface chemistry(1.08 mmol·g~(-1) and 0.54 mmol·g~(-1) for acidic and basic oxygenated groups, pH_(pzc)= 2.02). Maximum removal efficiency of aspirin observed was 94.28% after 60 min when the initial concentration was 100 mg·L~(-1), 0.5 g of adsorbent used,pH 3 and at a temperature of 30 ℃. The adsorption data were well fitted to the Freundlich isotherm model and obeyed the pseudo-second order kinetics model. The adsorption of aspirin onto STL-AC was exothermic in nature(ΔH~Θ=~(-1)3.808 k J·mol~(-1)) and had a negative entropy change, ΔS~Θ(-41.444 J·mol~(-1)). A negative Gibbs free energy, ΔG~Θ was obtained indicating feasibility and spontaneity of the adsorption process. The adsorption capacity of AC-STL(178.57 mg·g~(-1)) is considerably high compared to most adsorbents synthesized from various sources, due to the well-defined textural properties coupled with surface chemistry of STL-AC which favors aspirin adsorption. The results demonstrate the potential of STL-AC as aspirin adsorbent.     

Efficient adsorption to hexavalent chromium by iron oxalate modified D301:Characterization,performance and mechanisms

Chromium is a common harmful pollutant with high toxicity and low bearing capacity of soil and water. Excellent salinity resistance, a wide p H range, and high regeneration capacity were essential for qualified adsorbents used in removing hexavalent chromium(Cr(VI)) from polluted water. Herein, iron oxalate modified weak basic resin(IO@D301) for the removal of Cr(VI) was prepared by the impregnation method. The IO@D301 was characterized by scanning electron microscope(SEM), Fourier transform infrared spectroscopy(FTIR), X-Ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS). Owing to abundant amine, carboxyl groups and iron ions existing on the surface, IO@D301 possesses high adsorption and salinity resistance capacity for Cr(VI). The maximum adsorption capacity of IO301 towards Cr(VI) reached 201.30 mg·g~(-1) at 293 K and a p H of 5. The adsorption equilibrium was well fitted by the Freundlich model, and the adsorption process was described by the pseudofirst-order kinetics model as spontaneous and exothermic. The mechanism may be identified as electrostatic attraction, coordination, and reduction, which was confirmed by FT-IR and X-ray photoelectron spectroscopy.     

Studies on batch adsorptive removal of cadmium and nickel from synthetic waste water using silty clay originated from Balochistan–Pakistan

The potentials of silty clay(SC), acquired from Chaman, Balochistan, were investigated as adsorbent for Ni(Ⅱ)and Cd(Ⅱ) removal from contaminated media. The influence of different operating factors like dose, pH, temperature, and time of contact was explored, and optimum values were noted under batch adsorption method. Isothermal study was conducted with varying concentrations of solutions on optimized conditions and different adsorption models i.e., Langmuir, Freundlich, Temkin and Dubinin–Radushkevich(D–R) isotherm, which were employed to interpret the process. The isothermal data of both Ni(Ⅱ) and Cd(Ⅱ) were well fitted to Langmuir isotherm suggesting the formation of monolayer of metal ions on silty clay. The values of adsorption capacity noted for Ni(Ⅱ) and Cd(Ⅱ) were 3.603 mg·g~(-1) and 5.480 mg·g~(-)1, respectively. Kinetic studies affirmed that pseudo second order(PSO) kinetics was being obeyed by the removal of Ni(Ⅱ) and Cd(Ⅱ). Thermodynamic variables like free energy change(ΔG°), enthalpy change(ΔH°) and entropy change(ΔS°) were calculated. The negative value of ΔG° and the positive values of ΔH° and ΔS° unfolded that the removal process of both metal ions of by SC was spontaneous, endothermic and feasible.     

D72树脂对镨(Ⅲ)的吸附性能(英文)

In this work, the feasibility of using a macroporous strong acid ion exchange resin (D72) as an adsorbent for praseodymium (Ⅲ) was examined. The adsorption behavior and mechanism were investigated with various chemical methods and IR spectrometry. The results showed that the loading of Pr (III) ions was strongly dependent on pH of the medium and the optimal adsorption condition is in HAc-NaAc medium with pH value of 3.0. Adsorption kinetics of Pr (III) ions onto D72 resin could be best described by pseudo-second-order model. The maximum adsorption capacity of D72 for Pr (Ⅲ) was evaluated to be 294 mg·g 1 for the Langmuir model at 298K. The apparent activation energy, E a , was 14.71 kJ·mol 1 . The calculated data of thermodynamic parameters, ΔSΘ value of 100 J·mol 1 ·K 1 and ΔHΘ value of 8.89 kJ·mol 1 , indicate the endothermic nature of the adsorption process, while a decrease of ΔGΘ with increasing temperature indicates the spontaneous nature of the adsorption process. Finally, Pr (Ⅲ) can be eluted by using 1.00 mol·L 1 HCl-0.50 mol·L 1 NaCl solution and the D72 resin can be regenerated and reused. Thomas model was successfully applied to experimental data to predict the breakthrough curves and to determine the characteristic parameters of the column useful for process design. The characterization before and after adsorption of Pr (Ⅲ) ions on D72 resin was conformed by IR.     

磁性聚合物微球在Cr(VI)吸附分离中的应用(英文)

The magnetic poly-(methacrylate-divinyl benzene) microspheres with micron size were synthesized by modified suspension polymerization method.Adsorption of Cr(VI) from aqueous solution by magnetic poly-(MA-DVB) microspheres with surface amination was investigated.The adsorption processes were carried out under diversified conditions of pH value,adsorption time and temperature to evaluate the performance of the mag-netic microspheres.The optimum pH value for Cr(VI) adsorption was found as 3.The adsorption capacity increased with adsorption time and attained an optimum at 60 min.The adsorption processes for magnetic microspheres was endothermic reaction,and the adsorption capacity increased with increasing temperature.     

Amination of biochar surface from watermelon peel for toxic chromium removal enhancement

Watermelon peel residues were used to produce a new biochar by dehydration method. The new biochar has undergone two methods of chemical modification and the effect of this chemical modification on its ability to adsorb Cr(VI) ions from aqueous solution has been investigated. Three biochars, Melon-B, Melon-BO-NH_2 and Melon-BO-TETA, were made from watermelon peel via dehydration with 50% sulfuric acid to give Melon-B followed by oxidation with ozone and amination using ammonium hydroxide to give Melon-BO-NH_2 or Triethylenetetramine(TETA) to give Melon-BO-TETA. The prepared biochars were characterized by BET, BJH,SEM, FT-IR, TGA, DSC and EDAX analyses. The highest removal percentage of Cr(VI) ions was 69% for Melon-B,98% for Melon-BO-NH_2 and 99% for Melon-BO-TETA biochars of 100 mg·L~(-1) Cr(VI) ions initial concentration and 1.0 g·L~(-1) adsorbents dose. The unmodified biochar(Melon-B) and modified biochars(Melon-BO-NH_2 and Melon-BO-TETA) had maximum adsorption capacities(Qm) of 72.46, 123.46, and 333.33 mg·g~(-1), respectively.The amination of biochar reduced the pore size of modified biochar, whereas the surface area was enhanced.The obtained data of isotherm models were tested using different error function equations. The Freundlich,Tempkin and Langmuir isotherm models were best fitted to the experimental data of Melon-B, Melon-BO-NH_2 and Melon-BO-TETA, respectively. The adsorption rate was primarily controlled by pseudo-second–order rate model. Conclusively, the functional groups interactions are important for adsorption mechanisms and expected to control the adsorption process. The adsorption for the Melon-B, Melon-BO-NH_2 and Melon-BO-TETA could be explained for acid–base interaction and hydrogen bonding interaction.     

Effect of interlayer anions on chromium removal using Mg–Al layered double hydroxides:Kinetic,equilibrium and thermodynamic studies

The influence of interlayer anions such as NO3-, SO42-and Cl-on Mg–Al hydrotalcites for Cr(VI) removal from aqueous solution was studied. The structure of the prepared LDHs was characterized by XRD, SEM, FTIR, TGA, BET surface area and p Hzpc. The sorbent ability and sorption mechanisms were also investigated. The LDHs exhibit high removal for Cr(VI), and the sorbed amount depends on the nature of interlayer anion, which decreased in the following order: NO3-N Cl-N SO42-. Nitrate-containing LDH reached a Cr(VI) sorption equilibrium within only 30 min. The effects of operating conditions, including initial concentration, solution p H, agitation time and sorbent amount have been studied in batch mode. The optimum conditions were observed at an initial concentration of 100 mg·L-1, p H = 6, agitation time of 60 min and a sorbent dose of 2 g·L-1. The equilibrium data were fitted to the Langmuir, Freundlich and Dubinin–Radushkevich isotherm models. The Langmuir model was found to sufficiently describe the sorption process, offering a maximum sorption capacity of 71.91 mg·g-1. The sorption kinetic follows pseudo-second-order reaction with high accuracy. Thermodynamic parameters suggested that the sorption process is spontaneous and endothermic in nature.     

Adsorptive potential of Acacia nilotica based adsorbent for chromium(Ⅵ) from an aqueous phase

The objective of this research was to enhance adsorption capacity of Acacia nilotica(keekar) sawdust for the abatement of chromium bearing wastewater and to investigate the effect of process parameters on adsorption capacity. The sawdust was activated by acid wash and functionalized subsequently with formaldehyde.Functionalization of activated sawdust raised its chromium removal efficiency of almost 10% as compared to its adsorption removal efficiency of HCl treated sawdust in a batch adsorption study. Adsorption kinetic data provided better fitting with pseudo second order model. Maximum adsorption capacity calculated through the best fitting Langmuir model was 6.34 mg·g~(-1) and 8.2 mg·g~(-1) for HCl treated and formaldehyde functionalized sawdust adsorbents, respectively. The adsorption of Cr(Ⅵ) was endothermic when studied by varying temperature from 20 °C to 50 °C for both activated and functionalized adsorbents.     

正磷酸活化木质素吸附Cr(Ⅵ)的固定床实验和模型(英文)

The advantage of using an available and abundant residual biomass,such as lignin,as a raw material for activated carbons is that it provides additional economical interest to the technical studies.In the current investigation,a more complete understanding of adsorption of Cr(VI) from aqueous systems onto H3PO4-acid activated lignin has been achieved via microcolumns,which were operated under various process conditions.The practice of using microcolumn is appropriate for defining the adsorption parameters and for screening a large number of potential adsorbents.The effects of solution pH(2-8),initial metal ion concentration(0.483-1.981 mmol·L-1),flow rate(1.0-3.1 cm3·min-1),ionic strength(0.01-0.30 mmol·L-1) and adsorbent mass(0.11-0.465 g) on Cr(VI) adsorption were studied by assessing the microcolumn breakthrough curve.The microcolumn data were fitted by the Thomas model,the modified Dose model and the BDST model.As expected,the adsorption capacity increased with initial Cr(VI) concentration.High linear flow rates,pH values and ionic strength led to early breakthrough of Cr(VI).The model constants obtained in this study can be used for the design of pilot scale adsorption process.     

由飞灰合成的沸石吸附废水中染料的动态平衡

The removal performance of a basic dye, methylene blue (MB), in aqueous solution was investigated by adsorption process on single-phase and high-crystalline zeolite A (FA-ZA) and X (FA-ZX). Both adsorbents FA-ZA and FA-ZX were synthesized from fly ash prepared aluminosilicate gel followed by the hydrothermal treatment at 100°C with the control of Si/Al molar ratio, respectively. The properties of the synthetic zeolites and commercial grade zeolites, such as thermal stability, elemental composition, and cation exchange capacity, were investigated for comparison. Batch method was used to study the influential parameters, such as initial pH value of the solution, temperatures, and adsorbents dosage, on the adsorption process. The experimental data were well fitted by Ho’ pseudo-second-order model and liquid film diffusion model. The suitability of Langmuir and Freundlich isotherms to the equilibrium data was investigated in the solid-liquid system while the Langmuir model produces the best re-sults. Thermodynamic data (ΔH, ΔS, and ΔG) corresponding to the MB uptake were evaluated from the Langmuir model. In all the adsorption experiments, the adsorption capacity followed the order as follows: FA-ZX > FA-ZA. In addition, attempts were also made to regenerate the adsorbents.     

Performance evaluation of a modified step-feed anaerobic/anoxic/oxic process for organic and nutrient removal

A pilot scale modified step-feed process was improved to increase nutrient(N and P)and organic removal operations from municipal wastewater.It combined the step-feed process and a method named "University of Cape Town(UCT)".The effect of nutrient ratios and inflow distribution ratios were studied.The highest uptake efficiency of 95% for chemical oxygen demand(COD)has been achieved at the inflow distribution ratio of 40/35/25.However,maximum removal efficiency obtained for total nitrogen(TN)and phosphorus at 93% and 78%,respectively.The average mixed liquor suspended solids(MLSS)was 5500 mg·L~(-1).In addition,convenient values for dissolved oxygen(DO)concentration,and p H were obtained throughout different stages.The proposed system was identified to be an appropriate enhanced biological nutrient removal process for wastewater treatment plants owing to relatively high nutrient removal,sturdy sludge settle ability and COD removal.     

Removal of Reactive Red 198 from aqueous solution by combined method multi-walled carbon nanotubes and zero-valent iron:Equilibrium,kinetics, and thermodynamic

Dyes often include toxic,carcinogenic compounds and are harmful to humans' health.Therefore,removal of dyes from textile industry wastewater is essential.The present study aimed to evaluate the efficiency of the combination of zero valent iron(ZVI) powder and multi-walled carbon nanotubes(MWCNTs) in the removal of Reactive Red 198(RR198) dye from aqueous solution.This applied research was performed in a batch system in the laboratory scale.This study investigated the effect of various factors influencing dye removal,including contact time,p H,adsorbent dose,iron powder dose,initial dye concentration,and temperature.The equilibrium adsorption data were analyzed using three common adsorption models:Langmuir,Freundlich and Temkin.Besides,kinetic and thermodynamic parameters were used to establish the adsorption mechanism.The results showed,in pH =3,contact time = 100 min,ZVI dose = 5000 mg·L~(-1),and MWCNTs dose = 600 mg·L~(-1)in 100 mg·L~(-1)dye concentration,the adsorption efficiency increased to 99.16%.Also,adsorption kinetics was best described by the pseudo-second-order model.Equilibrium data fitted well with the Freundlich isotherm(R2= 0.99).The negative values of ΔG0and the positive value of ΔH0(91.76) indicate that the RR198 adsorption process is spontaneous and endothermic.According to the results,the combination of MWCNTs and ZVI was highly efficient in the removal of azo dyes.     

Insights into the adsorption performance and mechanism of Cr(Ⅵ) onto porous nanocomposite prepared from gossans and modified coal interface:Steric,energetic,and thermodynamic parameters interpretations

Herein,iron oxide/hydroxides deposits(gossans) were utilized,for the first time,in the fabrication of magnetite nanoparticles(MNPs) to load modified coal(MC).The as-synthesized MNPs@MC composite was characterized via different techniques and utilized for the Cr(Ⅵ) remediation.Experimental studies supported by theoretical treatment were applied to offer a new overview of the Cr(Ⅵ) adsorption geometry and mechanism at 25-45℃.Experimental results suggested that the Cr(Ⅵ) uptake was mainly governed ...     

Adsorption removal of o-nitrophenol and p-nitrophenol from wastewater by metal–organic framework Cr-BDC

In the present paper, a metal–organic framework Cr-BDC was prepared and used as adsorbent for adsorption of o-nitrophenol(ONP) and p-nitrophenol(PNP) from aqueous solutions. Cr-BDC was characterized by scanning electron microscopy, transmission electron microscope, X-ray diffraction and BET methods. The results indicate that Cr-BDC gets a very large specific surface area of 4128 m~2·g~(-1)and pore sizes are concentrated in 1 nm, which is a benefit for using for wastewater treatment. The influences of the adsorption conditions, such as temperature,solution concentration, adsorption time and reusability on adsorption performance were investigated. Cr-BDC exhibited an encouraging uptake capacity of 310.0 mg·g~(-1)for ONP, and adsorption capacity of Cr-BDC for ONP is significantly higher than that for PNP under suitable adsorption conditions. The characterizations of adsorption process were examined with the Lagergren pseudo-first-order, the pseudo-second-order kinetic model, and the intra-particular diffusion model. Kinetics experiments indicated that the pseudo-second-order model displayed the best correlation with adsorption kinetics data. Furthermore, our adsorption equilibrium data could be better described by the Freundlich equation. The results indicate that the as-prepared Cr-BDC is promising for use as an effective and economical adsorbent for ONP removal.     

Synthesis of a novel functional group-bridged magnetized bentonite adsorbent:Characterization,kinetics, isotherm,thermodynamics and regeneration

A novel magnetic adsorbent was synthesized by magnetizing bentonite by APTES-Fe_3O_4 via a functional groupbridged interaction. The characterization of APTES-Fe_3O_4/bentonite was conducted via transmission electron microscope(TEM), X-ray diffraction(XRD), Fourier transform infrared spectrophotometer(FT-IR), thermal gravimetric analysis(TGA), vibrating sample magnetometer(VSM), zeta potential analysis and Brunner–Emmet–Teller(BET). The APTES-Fe_3O_4/bentonite was assessed as adsorbents for methylene blue(MB) with a high adsorption capacity(91.83 mg·g~(-1)). Factors affecting the adsorption of MB(such as p H, equilibrium time, temperature and initial concentration) were investigated. The adsorption process completely reaches equilibrium after 120 min and the maximum sorption is achieved at p H 8.0. The adsorption trend follows the pseudosecond order kinetics model. The adsorption data gives good fits with Langmuir isotherm model. The parameter factor RLfalls between 0 and 1, indicating the adsorption of MB is favorable. The adsorption process is endothermic with positive ΔH~0 values. The positive values of ΔG~0 confirm the affinity of the adsorbent towards MB, and suggest an increased randomness at the solid–liquid interface during the adsorption process. Regeneration of the saturated adsorbent was easily carried out via gamma-irradiation.     

Removal of lead and cadmium ions by single and binary systems using phytogenic magnetic nanoparticles functionalized by 3-marcaptopropanic acid

The present research study is focused on green fabrication of superparamagnetic Phytogenic Magnetic Nanoparticles(PMNPs), and then its surface functionalization with 3-Mercaptopropionic acid(3-MPA). The resulting material(i.e. 3-MPA@PMNPs) characterized by FTIR, powder XRD, SEM, TEM, EDX, VSM, BET and TGA techniques and then further employed for the investigation of the adsorptive removal of lead(Pb~(2+)) and cadmium(Cd~(2+)) ions from aqueous solutions in single and binary systems. The material showed fastest adsorptive rate(98.23%) for Pb~(2+) and(96.5%) Cd~(2+)within the contact time of 60 min at pH 6.5 in the single system. The experimental data were fitted well to Langmuir isotherm, indicated monolayer adsorption of both metal ions onto 3-MPA@PMNPs and an estimated comparable adsorptive capacity of 68.41 mg·g~(-1)(Pb~(2+)) and 79.8 mg·g~(-1)(Cd~(2+)) at p H 6.5. However, kinetic data agreed well with pseudo-second-order model, and indicated that the removal mainly supported chemisorption and/or ion-exchange mechanism. Thermodynamic parameters such asΔGo, ΔHo, and ΔSo, were-3259.20, 119.35 and 20.73 for Pb2+, and-1491.10, 45.441 and 7.87 for Cd~(2+) at temperature 298.15 K, confirmed that adsorption was endothermic, spontaneous and favorable. The material demonstrated higher selectivity of Pb~(2+) and its removal efficiency was(98.20 ± 0.3)% in binary system experiments. The material persisted performance up-to seven(07) consecutive treatment cycles without losing their stability and offered comparable fastest magnetic separation(35 s) from aqueous solutions. Therefore, it is recommended that the prepared material can be employed to remove toxic heavy metal ions from water/wastewaters and this "green" method can easily be implemented at large scale in low economy countries.     

锰氧化物负载沸石固定床离子交换柱去除铀(VI)的研究

The adsorption of uranium (VI) on the manganese oxide coated zeolite (MOCZ) from aqueous solution was investigated in a fixed-bed column. The experiments were conducted to investigate the effects of bed height, flow rate, particle size, initial concentration of uranium (VI), initial pH, presence of salt and competitive ions. The U-uptake by MOCZ increased with initial uranium (VI) concentration and bed height, but decreased as the flow rate and particle size increased. In the presence of salt and competitive ions, the breakthrough time was shorter. The ad-sorption capacity reached a maximum at pH of 6.3. The Thomas model was applied to the experimental data to de-termine the characteristic parameters of the column for process design using linear regression. The breakthrough curves calculated from the model were in good agreement with the experimental data. The BDST model was used to study the influence of bed height on the adsorption of uranium (VI). Desorption of uranium (VI) in the MOCZ column was investigated. The column could be used for at least four adsorption-desorption cycles using 0.1 mol•L－1 NaHCO3 solution as the elution. After desorption and regeneration with deionized water, MOCZ could be reused to adsorb uranium (VI) at a comparable capacity. Compared to raw zeolite, MOCZ showed better capacity for uranium (VI) removal.     

Eco friendly adsorbents for removal of phenol from aqueous solution employing nanoparticle zero-valent iron synthesized from modified green tea bio-waste and supported on silty clay

The present research investigated a novel route for the synthesis of nanoparticle zero-valent iron(NZVI) utilizing an aqueous extract of green tea waste as a reductant with ferric chloride. Also, the supported nanoparticle zerovalent iron was synthesized using natural silty clay as a support material(SC-NZVI). The NZVI and SC-NZVI were characterized by infrared spectroscopy(FTIR), scanning electron microscope(SEM), X-ray diffraction(XRD),Brunauer–Emmett–Teller(BET), and zeta potential(ζ). The interpretation of the results demonstrated that the polyphenol and other antioxidants in green tea waste can be used as reduction and capping agents in NZVI synthesis, with silty clay an adequate support. Additionally, the experiments were carried out to explore phenol adsorption by NZVI and SC-NZVI. To determine the optimum conditions, the impact of diverse experimental factors(i.e., initial pH, adsorbent dose, temperature, and concentration of phenol) was studied. Langmuir, Freundlich,and Tempkin isotherms were used as representatives of adsorption equilibrium. The obtained results indicated that the adsorption processes for both NZVI and SC-NZVI well fitted by the Freundlich isotherm model. The appropriateness of pseudo_first_order and pseudo_second_order kinetics was investigated. The experimental kinetics data were good explained by the second-order model. The thermodynamic parameters(ΔH0, ΔS0, andΔG0) for NZVI and SC-NZVI were determined. The maximum removal rates of phenol at optimum conditions,when adsorbed onto NZVI and SC-NZVI, were found to be 94.8% and 90.1%, respectively.     

Investigation on molar heat capacity,standard molar enthalpy of combustion for guaiacol and acetyl guaiacol ester

The molar heat capacities(C_p) of guaiacol(CAS 90-50-1) and acetyl guaiacol ester(AGE, CAS 613-70-7) were determinated from 290 K to 350 K by differential scanning calorimetry(DSC), and expressed as a function of temperature. Two kinds of group contribution models were used to estimate the molar heat capacities of both guaiacol and AGE, the average relative deviation is less than 10%. The standard molar enthalpies of combustion of guaiacol and AGE were- 3590.0 k J·mol~(-1)and- 4522.1 k J·mol~(-1) by a precise thermal isolation Oxygen Bomb Calorimeter. The standard molar enthalpies of formation of guaiacol and AGE in a liquid state at298.15 K were calculated to be- 307.95 k J·mol~(-1) and- 448.72 k J·mol~(-1), respectively, based on the standard molar enthalpies of combustion. The thermodynamic properties are useful for exploiting the new synthesis method, engineering design and industry production of AGE using guaiacol as a raw material.     

用椰壳制活性炭吸附去除三价铋离子(英文)

In present study,we report the preparation of coconut shell activated carbon as adsorbent and its appli-cation for Bi(Ⅲ) removal from aqueous solutions.The developed adsorbent was characterized with scanning elec-tron microscope(SEM),Fourier Transform Infrared(FTIR),C,H,N,S analyzer,and BET surface area analyzer.The parameters examined include agitation time,initial concentration of Bi(Ⅲ),adsorbent dose and temperature.The maximum adsorption of Bi(Ⅲ)(98.72%) was observed at 250 mg·L-1 of Bi(Ⅲ) and adsorbent dose of 0.7 g when agitation was at 160 r·min-1 for 240 min at(299±2) K.The thermodynamic parameters such as Gibb’s free energy(△Gθ),enthalpy(△Hθ) and entropy(△Sθ) were evaluated.For the isotherm models applied to adsorption study,the Langmuir isotherm model fits better than the Freundlich isotherm.The maximum adsorption capacity from the Langmuir isotherm was 54.35 mg?g?1 of Bi(Ⅲ).The kinetic study of the adsorption shows that the pseudo second order model is more appropriate than the pseudo first order model.The result shows that,coconut shell ac-tivated carbon is an effective adsorbent to remove Bi(Ⅲ) from aqueous solutions with good adsorption capacity.