scholarly journals Sequestration of Pb(II) and Ni(II) ions from aqueous solution using microalga Rhizoclonium hookeri: adsorption thermodynamics, kinetics, and equilibrium studies

2016 ◽  
Vol 7 (2) ◽  
pp. 214-227 ◽  
Author(s):  
S. Suganya ◽  
A. Saravanan ◽  
P. Senthil Kumar ◽  
M. Yashwanthraj ◽  
P. Sundar Rajan ◽  
...  

In the present study, the microalga Rhizoclonium hookeri (RH) was effectively applied to remove the metal ions [Pb(II) and Ni(II)] from aqueous solution in batch adsorption mode experiments. The adsorption process was influenced by several operating parameters such as initial metal ion concentration, contact time, pH, particle size, adsorbent dose, and temperature. The maximum monolayer adsorption capacity of the RH was found to be 81.7 mg g−1 and 65.81 mg g−1 for Pb(II) and Ni(II) ions, respectively, at optimum conditions. The calculated thermodynamic parameters illustrated that the adsorption process was found to be spontaneous and endothermic in nature. Experimental data were analyzed in terms of pseudo-first order, pseudo-second order, and Elovich kinetic models. The results showed that the removal of Pb(II) and Ni(II) ions followed the pseudo-second order kinetics. The adsorption isotherm data were described using two and three parameter models. The results indicate that the adsorption data were best fitted with the Sips isotherm model. Consequently, the microalga RH with good adsorbability and reusability could be used as an effective adsorbent for the adsorption of Pb(II) and Ni(II) ions from wastewater.

2011 ◽  
Vol 8 (1) ◽  
pp. 373-385 ◽  
Author(s):  
B. Sathyanarayana ◽  
K. Seshaiah

The sorption of manganese(II) and nickel(II) onto two adsorbents, kaolinite and bentonite from aqueous solution was studied in batch mode. Effect of pH, contact time, adsorbent dose, and initial metal ion concentration on adsorption was investigated. The adsorbents exhibit good sorption potential for manganese(II) and nickel(II) with a peak value at pH 5 and pH 6 respectively. More than 70% sorption occurred within 20 min for manganese(II) and nickel(II) and equilibrium was attained at 90 min. for manganese(II) and 120 min for nickel(II). Freundlich and Langmuir's mathematical models were used to describe batch adsorption. The adsorption was found to be favourable with respect to both the isotherms. The adsorption of the two metal ions from aqueous solution onto two adsorbents followed pseudo-second order kinetics.


2017 ◽  
Vol 75 (10) ◽  
pp. 2454-2464 ◽  
Author(s):  
O. S. Lawal ◽  
O. S. Ayanda ◽  
O. O. Rabiu ◽  
K. O. Adebowale

The biosorption characteristics of Pb (II) ions from aqueous solution using black walnut (Juglans nigra) seed husk (WSH) biomass were investigated using batch adsorption techniques. The effects of pH, contact time, initial Pb (II) ion concentration, and temperature were studied. The Langmuir, Freundlich and Temkin isotherms were used to analyze the equilibrium data. It was found that the adsorption of Pb (II) ions onto WSH was best described by the Freundlich adsorption model. Biosorption kinetics data were tested using the pseudo-first order and pseudo-second order models, and it was observed that the kinetics data fitted the pseudo-second order model. Thermodynamic parameters such as standard Gibbs free energy change (ΔG0), standard enthalpy change (ΔH0) and standard entropy change (ΔS0) were evaluated. The result showed that biosorption of Pb (II) ions onto WSH was spontaneous and endothermic in nature. The FTIR study showed that the following functional groups: O-H, C = O, C-O, C-H and N-H were involved in binding Pb (II) ions to the biomass.


2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Muhammad Hamid Raza ◽  
Aqsa Sadiq ◽  
Umar Farooq ◽  
Makshoof Athar ◽  
Tajamal Hussain ◽  
...  

Batch scale studies for the adsorption potential of novel biosorbentPhragmites karka(Trin), in its natural and treated forms, were performed for removal of mercury ions from aqueous solution. The study was carried out at different parameters to obtain optimum conditions of pH, biosorbent dose, agitation speed, time of contact, temperature, and initial metal ion concentration. To analyze the suitability of the process and maximum amount of metal uptake, Dubinin-Radushkevich (D-R) model, Freundlich isotherm, and Langmuir isotherm were applied. The values ofqmaxfor natural and treated biosorbents were found at 1.79 and 2.27 mg/g, respectively. The optimum values of contact time and agitation speed were found at 50 min and 150 rpm for natural biosorbent whereas 40 min and 100 rpm for treated biosorbent, respectively. The optimum biosorption capacities were observed at pH 4 and temperature 313 K for both naturalP. karkaand treatedP. karka.RLvalues indicate that comparatively treatedP. karkawas more feasible for mercury adsorption compared to naturalP. karka. Both pseudo-first-order and pseudo-second-order kinetic models were applied and it was found that data fit best to the pseudo-second-order kinetic model. Thermodynamic studies indicate that adsorption process was spontaneous, feasible, and endothermic.


2021 ◽  
Author(s):  
Sabarish Radoor ◽  
Jasila Karayil ◽  
Aswathy Jayakumar ◽  
Jyotishkumar Parameswaranpillai ◽  
Suchart Siengchin

Abstract In the present work, we modified ZSM-5 zeolite using a bio polymer poly (diallyl dimethyl ammonium chloride) and employed it for the removal of cationic dye, methylene blue from aqueous solution. The chemical and physical properties of the modified ZSM-5 zeolite were investigated using XRD, FTIR, SEM, TEM, nitrogen adsorption, TGA and 27Al NMR. Modified ZSM-5 zeolite possesses high surface area and pore diameter which was confirmed from SEM, TEM and nitrogen adsorption analysis. Adsorption of methylene blue on zeolite was investigated by batch adsorption technique. The effect of different parameters such as zeolite dosage, initial methylene blue concentration, temperature, pH and contact time on the adsorption process was discussed. Maximum adsorption capacity (4.31 mg/g) was achieved using 0.1g of modified ZSM-5 zeolite at the optimum conditions (initial dye concentration: 10 mg/L, pH: 10, temperature:30oC and contact time: 300 min). The experimental data were fitted into Langmuir and Freundlich models and the results indicate that the adsorption process followed Freundlich isotherm. Kinetic data were investigated using pseudo-first-order and pseudo-second-order models. Kinetic analysis indicates that pseudo-second-order model is more suitable to describe adsorption of MB on modified ZSM-5 zeolite. The reusability test suggests that the adsorbent could be reused at least six times without significant loss in removal efficiency.


2013 ◽  
Vol 63 (1) ◽  
Author(s):  
S. T. Song ◽  
N. Saman ◽  
K. Johari ◽  
H. B. Mat

Sorption potential of rice residues for Hg(II) removal from aqueous solution was investigated. Rice husk (RH) and rice straw (RS) were selected and treated with sodium hydroxide (NaOH). The raw and modified adsorbents were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and BET surface area measurements. The effects of pH, initial ion concentration, and agitation time on the removal process were studied in batch adsorption experiments. Two simple kinetic models, which are pseudo-first-order and pseudo-second-order, were tested to investigate the adsorption mechanisms. The kinetic data fits to pseudo second order model with correlation coefficients greater than 0.99 for all adsorbents. The equilibrium data fitted well with the Langmuir compared to Freundlich isotherm models. Alkali-treated adsorbent obtained larger surface area and RH-NaOH showed highest adsorption capacity followed by RS-Pure > RH-Pure > RS-NaOH. The maximum removal efficiency obtained by RH-NaOH and RS-Pure was 42 mg/l (80%) at pH 6.5 and with 2 days contact time (for 50 mg/l initial concentration and 25 mg adsorbents). 


2021 ◽  
Vol 411 ◽  
pp. 79-91
Author(s):  
Muhammad Imran-Shaukat ◽  
Nur Rafikah binti Rosli ◽  
Rafeah Wahi ◽  
Sharifah Mona Abd Aziz Abdullah ◽  
Zainab Ngaini

In this study, coconut shells were converted into biochar via pyrolysis and chemically modified via an acid-base treatment to enrich its adsorption capabilities. Batch experiments were carried out to analyze the adsorption potential of the modified coconut shell (MCSC) or removal of chromium, nickel, and copper from aqueous solution. The chemical modification increased the surface area of MCSC to 185.712 m2/g. Batch adsorption study using MCSC resulted in 99% removal of copper, 95% (nickel), and 39% (chromium). The adsorption of studied metal ions fitted well with Langmuir isotherm, showing a monolayer adsorption process. A kinetic analysis showed that all the samples match a strong correlation coefficient in pseudo-second-order (R2>0.95), indicating the occurrence of a chemical adsorption process.


2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
C. A. Cimá-Mukul ◽  
Youness Abdellaoui ◽  
Mohamed Abatal ◽  
Joel Vargas ◽  
Arlette A. Santiago ◽  
...  

Leucaena leucocephala is a potential source of polyphenols widely available in southern Mexico. This work highlights the extraction of polyphenols from Leucaena leucocephala leaves waste (LLEPs) and the evaluation of their efficiency to remove the single and multicomponent Pb(II) and Cd(II) metal ions from aqueous solutions. Batch test conditions were carried out to examine the effects of contact time, initial metal ion concentration, and adsorbent dosage on the biosorption process. The surface textures and the composition of the LLEP biosorbent was characterized using pH of point of zero charge (pHPZC), attenuated total reflectance Fourier transform infrared (ATR-FTIR), and matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry, respectively. Further analysis using ATR-FTIR after adsorption contact of biosorbent was also investigated. The highest Langmuir saturation monolayer adsorption capacity, qm, for the removal of Pb(II) by LLEPs was obtained as 25.51 and 21.55 mg/g in mono- and bimetal solutions, respectively. The pseudo-second-order model provided the best fit for the kinetic data obtained for the removal of Pb(II), Cd(II), and their mixture, and the k2 values depend on the adsorbent mass. This implied that the chemisorption process might be the mechanism of the solute ions-LLEPs interaction in this study. Furthermore, nearly 100% removal of lead and cadmium individually and 95% of their mixture was found using 0.9 g of LLEPs.


2016 ◽  
Vol 74 (7) ◽  
pp. 1644-1657 ◽  
Author(s):  
Mona El-Sayed ◽  
Gh. Eshaq ◽  
A. E. ElMetwally

In our study, Mg–Al–Zn mingled oxides were prepared by the co-precipitation method. The structure, composition, morphology and thermal stability of the synthesized Mg–Al–Zn mingled oxides were analyzed by powder X-ray diffraction, Fourier transform infrared spectrometry, N2 physisorption, scanning electron microscopy, differential scanning calorimetry and thermogravimetry. Batch experiments were performed to study the adsorption behavior of cobalt(II) and nickel(II) as a function of pH, contact time, initial metal ion concentration, and adsorbent dose. The maximum adsorption capacity of Mg–Al–Zn mingled oxides for cobalt and nickel metal ions was 116.7 mg g−1, and 70.4 mg g−1, respectively. The experimental data were analyzed using pseudo-first- and pseudo-second-order kinetic models in linear and nonlinear regression analysis. The kinetic studies showed that the adsorption process could be described by the pseudo-second-order kinetic model. Experimental equilibrium data were well represented by Langmuir and Freundlich isotherm models. Also, the maximum monolayer capacity, qmax, obtained was 113.8 mg g−1, and 79.4 mg g−1 for Co(II), and Ni(II), respectively. Our results showed that Mg–Al–Zn mingled oxides can be used as an efficient adsorbent material for removal of heavy metals from industrial wastewater samples.


2014 ◽  
Vol 7 ◽  
pp. ASWR.S16488 ◽  
Author(s):  
Ruchi Pandey ◽  
Nasreen Ghazi Ansari ◽  
Ram Lakhan Prasad ◽  
Ramesh Chandra Murthy

This paper describes the adsorption of Cd(II) ions from aqueous solutions by modified Cucumis sativus peel (CSP) by HCl treatment. The optimum pH, adsorbent mass, contact time, and initial ion concentration were determined. The maximum removal efficiency was 84.85% for 20 mg/L Cd(II) ion at pH 5. The adsorption isotherms were obtained using concentrations of the metal ions ranging from 5 to 150 mg/L. The adsorption process follows Langmuir isotherm and pseudo-second-order reaction kinetics. CSPs exhibit monolayer adsorption capacity of 58.14 mg/g at 298 K. The paper also discusses the thermodynamic parameters of the adsorption (the Gibbs free energy, entropy, and enthalpy). Our results establish that the adsorption process was spontaneous and endothermic under normal conditions.


2014 ◽  
Vol 694 ◽  
pp. 382-386 ◽  
Author(s):  
Bo Liang ◽  
Wan He Zhao ◽  
Kai Huang ◽  
Hong Min Zhu

The removal of Mn (II) ion by saponified garlic peel (S-GP) was investigated using batch adsorption. SEM and FT-IR were employed to investigate the physical and chemical properties of S-GP. The adsorption was evaluated as a function of initial metal ion concentration, contact time and temperature. The maximum adsorption capacity for Mn (II) was 0.51 mol/kg, and the adsorption process followed the Langmuir model. Pseudo-second-order models fitted the experimental data well and kinetic parameters, rate constants, equilibrium sorption capacity and related correlation coefficients at various temperatures were calculated and discussed. A possible adsorption mechanism based on a cation exchange was proposed for the adsorption of Mn (II).


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