scholarly journals Efficient Adsorption of Lead (II) from Aqueous Phase Solutions Using Polypyrrole-Based Activated Carbon

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2020 ◽  
Author(s):  
Abdulaziz Ali Alghamdi ◽  
Abdel-Basit Al-Odayni ◽  
Waseem Sharaf Saeed ◽  
Abdullah Al-Kahtani ◽  
Fahad A. Alharthi ◽  
...  

In this study, polypyrrole-based activated carbon was prepared by the carbonization of polypyrrole at 650 °C for 2 h in the presence of four-times the mass of KOH as a chemical activator. The structural and morphological properties of the product (polypyrrole-based activated carbon (PPyAC4)), analyzed by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and thermogravimetric analysis, support its applicability as an adsorbent. The adsorption characteristics of PPyAC4 were examined through the adsorption of lead ions from aqueous solutions. The influence of various factors, including initial ion concentration, pH, contact time, and adsorbent dose, on the adsorption of Pb2+ was investigated to identify the optimum adsorption conditions. The experimental data fit well to the pseudo-second-order kinetic model (R2 = 0.9997) and the Freundlich isotherm equation (R2 = 0.9950), suggesting a chemisorption pathway. The adsorption capacity was found to increase with increases in time and initial concentration, while it decreased with an increase in adsorbent dose. Additionally, the highest adsorption was attained at pH 5.5. The calculated maximum capacity, qm, determined from the Langmuir model was 50 mg/g.

2017 ◽  
Vol 15 (6) ◽  
pp. 1015-1027 ◽  
Author(s):  
Olushola S. Ayanda ◽  
Simphiwe M. Nelana ◽  
Leslie F. Petrik ◽  
Eliazer B. Naidoo

Abstract The application of nano-TiO2 as adsorbent combined with ultrasound for the degradation of N-acetyl-para-aminophenol (AAP) from aqueous solution was investigated. The nano-TiO2 was characterized by means of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR). Experimental results revealed that the adsorption of AAP by nano-TiO2 fitted the pseudo-second-order kinetic model, the equilibrium could be explained by the Freundlich isotherm and the treatment process is exothermic. The optimum removal efficiency of AAP (128.89 mg/g (77.33%)) was achieved at pH 4 when 0.03 g of nano-TiO2 was mixed with 50 mL of 100 mg/L AAP aqueous solution at ambient temperature, 60 min contact time, and a stirring speed of 120 rpm. Ultrasound at 20 kHz and pH 3 was favorable and it resulted in 52.61% and 57.43% removal efficiency with and without the addition of nano-TiO2, respectively. The degradation of AAP by ultrasound followed by nano-TiO2 treatment resulted in approximately 99.50% removal efficiency. This study showed that a sequential ultrasound and nano-TiO2 treatment process could be employed for the removal of AAP or other emerging water and wastewater contaminants.


Separations ◽  
2021 ◽  
Vol 8 (11) ◽  
pp. 224
Author(s):  
Ismat H. Ali ◽  
Mutasem Z. Bani-Fwaz ◽  
Adel A. El-Zahhar ◽  
Riadh Marzouki ◽  
Mosbah Jemmali ◽  
...  

In this study, a gum Arabic-magnetite nanocomposite (GA/MNPs) was synthesized using the solution method. The prepared nanocomposite was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). The prepared composite was evaluated for the adsorption of lead(II) ions from aqueous solutions. The controlling factors such as pH, contact time, adsorbent dose, initial ion concentration, and temperature were investigated. The optimum adsorption conditions were found to be 0.3 g/50 mL, pH = 6.00, and contact time of 30 min. The experimental data well fitted the pseudo-second-order kinetic model and the Langmuir isotherm model. The maximum adsorption capacity was determined as 50.5 mg/g. Thermodynamic parameters were calculated postulating an endothermic and spontaneous process and a physio-sorption pathway.


2019 ◽  
Vol 9 (4) ◽  
pp. 266-279
Author(s):  
Karim Hnana ◽  
Abdeslam Barhoun ◽  
Khalid Draoui

Clay materials combined with other compounds are intensely used in several fields. The present study focuses on the synthesis of organoclays and nanocomposites based on the intercalation of surfactant and biopolymer into swelling Moroccan clay. The produced materials were used in the removal of glyphosate from the aqueous medium. The organoclay was obtained by the intercalation of cetyltrimethylammonium bromide (CTAB) in the interlamellar space of stevensite, and the nanocomposite was fabricated by the direct interaction between the stevensite and chitosan. These materials were characterized by mean X-Ray Diffraction, Fourier Transform Infra-Red Spectroscopy (FTIR), Thermal Analysis and Transmission Electron Microscopy (TEM). The results showed that the stevensite is the dominant clay mineral of Ghassoul and confirmed that the nanocomposite has an intercalated clay structure.  The batch mode was accomplished to quantify the glyphosate removal capacity from aqueous solution by these materials. The enhancement of hydrophobic properties has promoted the retention of the herbicide. The pseudo-second-order kinetic model of adsorption was the most suitable to describe the process of adsorption and the Freundlich isotherm equation fitted satisfactory the adsorption isotherm data. The capacity of adsorption was more outstanding for the nanocomposite chitosan/Ghassoul and reached a significant value of 159.10 mg.g-1. The nanocomposites based on chitosan/Ghassoul could be considered as promising materials for treatments of pesticide-contaminated water.


2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Tamirat Dula ◽  
Khalid Siraj ◽  
Shimeles Addisu Kitte

This study reports on the adsorption of Hexavalent Chromium from aqueous solutions using activated carbon prepared from bamboo (Oxytenanthera abyssinica) waste by KOH activation heating in an electrical furnace at 1073 K for 3 hrs. Batch adsorption experiments were also carried out as a function of pH, contact time, initial concentration of the adsorbate, adsorbent dosage, and temperature of the solution. Kinetic studies of the data showed that the adsorption follows the pseudo-second-order kinetic model. Thermodynamic parameters showed that adsorption on the surface of BWAC was feasible, spontaneous in nature, and exothermic between temperatures of 298 and 318 K. The equilibrium data better fitted the Freundlich isotherm model for studying the adsorption behavior of Hexavalent Chromium by BWAC. IR spectrum for loaded and unloaded BWAC was obtained using FT-IR spectrophotometer. Adsorption efficiency and capacity of Hexavalent Chromium were found to be 98.28% at pH 2 and 59.23 mg/g at 300 K.


2013 ◽  
Vol 69 (1) ◽  
pp. 147-155 ◽  
Author(s):  
Babak Kakavandi ◽  
Ali Esrafili ◽  
Anoushiravan Mohseni-Bandpi ◽  
Ahmad Jonidi Jafari ◽  
Roshanak Rezaei Kalantary

In the present study, powder activated carbon (PAC) combined with Fe3O4 magnetite nanoparticles (MNPs) were used for the preparation of magnetic composites (MNPs-PAC), which was used as an adsorbent for amoxicillin (AMX) removal. The properties of magnetic activated carbon were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Brunaeur, Emmett and Teller and vibrating sample magnetometer. The operational factors affecting adsorption such as pH, contact time, adsorbent dosage, initial AMX concentration and temperature were studied in detail. The high surface area and saturation magnetization for the synthesized adsorbent were found to be 671.2 m2/g and 6.94 emu/g, respectively. The equilibrium time of the adsorption process was 90 min. Studies of adsorption equilibrium and kinetic models revealed that the adsorption of AMX onto MNPs-PAC followed Freundlich and Langmuir isotherms and pseudo-second-order kinetic models. The calculated values of the thermodynamic parameters, such as ΔG°, ΔH° and ΔS° demonstrated that the AMX adsorption was endothermic and spontaneous in nature. It could be concluded that MNPs-PAC have a great potential for antibiotic removal from aquatic media.


2011 ◽  
Vol 183-185 ◽  
pp. 362-366 ◽  
Author(s):  
Jun Li ◽  
Ming Zhen Hu

Adsorption removal of a cationic dye, rhodamine B (RhB) from water onto rectorite and sepiolite was investigated. The rectorite and sepiolite were characterized by Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). Attempts were made to fit the isothermal data using Langmuir and Freundlich equations. The experimental results have demonstrated that the equilibrium data are fitted well by a Freundlich isotherm equation. Pseudo-first-order and pseudo-second-order models were considered to evaluate the rate parameters. The experimental data were well described by the pseudo-second-order kinetic model. The results indicate that the rectorite exhibited higher adsorption capacity for the removal of RhB than sepiolite and could be employed as a low-cost alternative in wastewater treatment for the removal of cationic dyes.


2020 ◽  
Vol 69 (7) ◽  
pp. 678-693
Author(s):  
R. Aouay ◽  
S. Jebri ◽  
A. Rebelo ◽  
J. M. F. Ferreira ◽  
I. Khattech

Abstract Hydroxyapatite powders were synthesized according to a wet precipitation route and then subjected to heat treatments within the temperature range of 200–800 °C. The prepared samples were tested as sorbents for cadmium in an aqueous medium. The best performances were obtained with the material treated at 200 °C (HAp200), as the relevant sorbent textural features (SBET – specific surface area and Vp – total volume of pores) were least affected at this low calcination temperature. The maximum adsorption capacity at standard ambient temperature and pressure was 216.6 mg g−1, which increased to 240.7 mg g−1 by increasing the temperature from 25 to 40 °C, suggesting an endothermic nature of the adsorption process. Moreover, these data indicated that a thermal treatment at 200 °C enhanced the ability of the material in Cd2+ uptake by more than 100% compared to other similar studies. The adsorption kinetic process was better described by the pseudo-second-order kinetic model. Langmuir, Freundlich, and Dubinin–Kaganer–Radushkevich isotherms were applied to describe the sorption behaviour of Cd2+ ions onto the best adsorbent. Furthermore, a thermodynamic study was also performed to determine ΔH°, ΔS°, and ΔG° of the sorption process of this adsorbent. The adsorption mechanisms were investigated by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy-transmission electron microscopy (SEM-TEM) observations.


2020 ◽  
Vol 11 (2) ◽  
pp. 9227-9241

High amounts of ammonium (NH4+) discharged in receiving water can lead to eutrophication. The adsorption of NH4+ from synthetic solution onto granular activated carbon (GAC) was scrutinized with respect to initial solute concentration (10 mg L−1), solution volume (0.2 L), adsorbent dosage (4 – 20 g), and contact time. Experimental data can be well described by the pseudo-second-order kinetic model (R2 > 0.994) and Freundlich isotherm model (R2 = 0.936), suggesting that chemisorption and multilayer adsorption occurred. Furthermore, this study explored the feasibility of using the Freundlich isotherm model to estimate the removal efficiency or required amount of adsorbent. The result findings indicated that GAC has a good potential to adsorb NH4+ from water and thus giving new insights into environmental engineering practices.


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.


2011 ◽  
Vol 71-78 ◽  
pp. 2988-2991
Author(s):  
Yuan Hong Wang ◽  
Yun Yu ◽  
Rui Qun Liu ◽  
Wei Feng Liu

Present study deals with the evaluation of biosorptive removal of nickel byFlavobacterium sp.Experiments have been carried out to find the effect of various parameters such as initial pH, contact time and initial metal ion concentration. Adsorption equilibrium studies showed that Ni(II) adsorption data followed the Langmuir model, the maximum binding capacity of Ni(II) was 64.20 mg/g at pH 7.0. Kinetics of nickel biosorption by Flavobacterium sp.biomass is better described by pseudo second order kinetic model. The equilibrium isotherm data are very well represented by Langmuir isotherm equation, which confirmed the monolayer coverage of nickel onto Flavobacterium sp.biomass. It was also clearly observed that The present study indicated thatFlavobacterium sp.biomass may be used as an inexpensive and effective biosorbent for the removal of Ni(II) ions from environmental wastewater.


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