Parametric Study of the Adsorption of Pb (II) and Cr (VI) Ions on Modified PAN-Kapok Fibers

2021 ◽  
Vol 880 ◽  
pp. 133-138
Author(s):  
Jericko C. Alipoyo ◽  
Venniece Etienne B. Magoncia ◽  
Angel Ainaleigh M. Perido ◽  
Mary Donnabelle L. Balela

This paper presents a parametric study on the adsorptive property of NaOH-treated polyacrylonitrile (PAN)-kapok fibers for the removal of Pb (II) and Cr (VI) ions in aqueous solutions. Generally, the NaOH-hydrolyzed PAN-kapok favors the adsorption of Pb (II) compared to Cr (VI). The adsorption capacity was in the range of 41.67-83.33 mg/g as the initial Pb (II) concentration was increased from 50 to 100 ppm. Similarly, the adsorption capacity for Cr (VI) was from 8.24 to 15.81 mg/g as the initial concentration was raised from 50 to 150 ppm. The adsorption capacity was also enhanced by increasing the adsorbent dosage. Finally, uptake of Pb (II) at the early stages of the adsorption was fast, with adsorption capacity reaching ~120 mg/g.

2015 ◽  
Vol 1125 ◽  
pp. 281-285
Author(s):  
Siti Aishah Muhmed ◽  
Mohd Ghazali Mohd Nawawi

Crosslinked Sago Starch (CSS) was prepared by crosslinking native starch with Sodium Trimetaphosphate. As a biodegradable adsorbent, CSS was used to remove methylene blue (MB) from the aqueous solution based on its characterization, including the granule morphology, crystalline nature and molecular structure. The adsorption capacity of CSS was evaluated as a function of pH, adsorbent dosage, initial concentration and time. It was favorable for adsorption under condition of neutral and at high initial concentration. The adsorption capacity trend was decreased with increasing the adsorbent dosage. The equilibrium isotherms were conducted using Langmuir, Freundlich and Tempkin model. It has been demonstrated that the better agreement was Langmuir isotherm with correlation coefficient of 0.99, equilibrium adsorption capacity of 3.75 mg g-1, chi-square test, χ2 of 0.03% and corresponding contact time of 4 hours. The pseudo-first-order, pseudo-second-order and intra-particle diffusion were used to fit adsorption data in the kinetic studies. And results showed that the adsorption kinetics was more accurately described by the pseudo-second-order model with correlation coefficient, R2 of 0.99 and standard deviation, SSE of 0.12%. The obtained results suggest that CSS could be promising candidates as an adsorbent for dye removal.


2019 ◽  
Vol 6 (2) ◽  
pp. 66-74 ◽  
Author(s):  
Raziyeh Hosseini ◽  
Mohammad Hossein Sayadi ◽  
Hossein Shekari

The research was conducted with an aim to assess the efficiency of copper oxide nanoparticles as an adsorbent to remove Ni and Cr. The effect of pH, adsorbent dosage, contact time, initial concentration of metals (Ni and Cr) on the adsorption rate was evaluated and removal of these elements from aqueous solutions was measured using Atomic Absorption Spectrum System (Conter AA700). Moreover, the kinetic and isotherm besides thermodynamic adsorption models were assessed. The highest Ni and Cr removal rate occurred at an optimal pH of 7, and an initial concentration of 30 mg/L, a time period of 30 minutes, and 1 g/L of copper oxide nanoparticles. In fact, with the increase of adsorbent dosage and contact time, the removal efficiency increased and with initial concentration increase of Ni and Cr ions, the removal efficiency reduced. The correlation coefficient of isotherm models viz. Langmuir, Freundlich, Temkin, Redlich-Peterson, and Koble-Corrigan showed that Ni and Cr adsorption via copper oxide nanoparticles better follows the Langmuir model in relation to other models. The results showed that kinetic adsorption of Ni and Cr via copper oxide nanoparticles follows the second order pseudo model with correlation coefficients above 0.99. In addition, the achieved thermodynamic constants revealed that the adsorption process of metals (i.e., Ni and Cr) via copper oxide nanoparticles was endothermic and spontaneous and the reaction enthalpy values for these metals were 17.727 and 11.862 kJ/mol, respectively. In conclusion, copper oxide nanoparticles can be used as effective and environmentally compatible adsorbents to remove Ni and Cr ions from the aqueous solutions


2018 ◽  
Vol 5 (4) ◽  
pp. 187-196 ◽  
Author(s):  
Soheila Chavoshan ◽  
Maryam Khodadadi ◽  
Negin Nasseh ◽  
Ayat Hossein Panahi ◽  
Aliyeh Hosseinnejad

Background: Drugs, especially antibiotics, are one of the serious problems of modern life and the main pollution sources of the environment, especially in the last decade, which are harmful to human health and environment. The aim of this study was to investigate the removal of penicillin G from aqueous solutions using single-walled and multi-walled carbon nanotubes. Methods: In this study, the effect of different parameters including pH (3, 5, 7, 9, and 11), initial concentration of pollutant (50, 100, 150, and 200 mg/l), absorbent dose (0.25, 0.5, 0.75, and 1 g/L), mixing speed (0, 100, 200, and 300 rpm), and temperature (10, 15, 25, 35, 45°C) were investigated. The Langmuir, Freundlich, Temkin, BET, Dubinin-Radushkevich isotherms and adsorption kinetics of the first- and second-order equations were determined. Results: The results showed that the efficiency of single-walled and multi-walled carbon nanotubes in the removal of penicillin G was 68.25% and 56.37%, respectively, and adsorption capacity of the nanotubes was 141 mg/g and 119 mg/g at initial concentration of 50 mg/l and pH=5 with adsorption dose of 0.8 g/L for 105 minutes at 300 rpm and temperature of 10°C from aqueous solutions. Also, it was revealed that the adsorption process had the highest correlation with the Langmuir model and secondorder kinetics, and the maximum adsorption capacity based on Langmuir model was 373.80 mg/g. Conclusion: According to the results, it was found that single-walled and multi-walled carbon nanotubes can be used as effective absorbents in the removal of penicillin G from aqueous solutions.


2021 ◽  
Vol 15 (2) ◽  
pp. 263-273
Author(s):  
Iman Mobasherpour ◽  
◽  
Masomeh Javaherai ◽  
Esmail Salahi ◽  
Mohsen Ebrahimi ◽  
...  

Removal of lead from aqueous solutions was studied using nanocomposite absorbent of bentonite/-alumina. The novel absorbent was characterized using XRD, FT-IR and SEM-EDX. Absorption process optimization using response surface methodology (RSM) and experimental design was performed with central composite design technique. The effects of Pb(II) initial concentration, adsorbent dosage, and composite percentage on Pb(II) removal percentage and adsorption capacity were examined. The adsorption capacity of 166.559 mg/g and removal % of 82.9887 with desirability equal to 0.763 were obtained for optimal initial concentration of 200 mg•l-1, adsorbent dosage of 0.5 mg•l-1, and composite percentage of 7.08 % determined using RSM design. The equilibrium adsorption data were investigated by Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. It was found that Freundlich isotherm model fits better compared with other models.


BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 9413-9428
Author(s):  
Yande Jing ◽  
Xuan Wang ◽  
Dan Wang ◽  
Qianqian Yang

The current study aimed to optimize Cd(II) removal from aqueous solutions by a composite adsorbent (BCB) prepared from Alternanthera philoxeroides (AP) biochar (BC) and bentonite (BE) using response surface methodology (RSM). The results showed that the loading of BE did not significantly change the microstructure of BC but increased the number of functional groups. The X-ray diffraction (XRD) analysis showed that precipitation was the primary mechanism of Cd(II) adsorption. The adsorption behavior for Cd(II) fitted the Freundlich model. The pH, adsorbent dosage, and initial Cd(II) concentration were the main influencing factors affecting Cd(II) adsorption. There were significant interactions between pH and adsorbent dosage, adsorbent dosage, and initial concentration. The optimum adsorption conditions for Cd(II) with the maximum adsorption level of 89.4% were: 6.55 pH, 0.04 g adsorbent dosage, and 68.7 mg∙L-1 initial concentration. Overall, the BCB exhibited great potential as an efficient sorbent for the Cd(II) removal from aqueous solutions.


2012 ◽  
Vol 518-523 ◽  
pp. 797-800 ◽  
Author(s):  
Xuan Lin Tang ◽  
Huan Zhen Zhang ◽  
Shuang Zhao ◽  
Shu Fen Gong

CAL beads were made by dropping wise mixture of chitosan and alumina into NaOH solution. Effects of contact time, adsorbent dosage, initial concentration and pH on fluoride removal were carried out by batch experiments. Results show that adsorption rate was relatively rapid in the first 6 h, thereafter distinctly decreased until adsorption reached the equilibrium within 48 h, at this time, adsorption capacity was up to 0.67 mg/g, which was much higher than raw chitosan (0.052 mg/g). Fluoride removal increased significantly with an increase of adsorbent dosage, however, it rose slowly when the adsorbent dosage was above 16 g/L. Adsorption capacity reduced from 0.75 mg/g to 0.64mg/g when solution pH rose from 4 to 7, nevertheless, adsorption was relatively independent on solution pH between 7 and 10.


Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1161
Author(s):  
Somayeh Rahdar ◽  
Abbas Rahdar ◽  
Mostafa Sattari ◽  
Laleh Divband Hafshejani ◽  
Athanasia K. Tolkou ◽  
...  

Dyes are known as one of the most dangerous industrial pollutants which can cause skin diseases, allergy, and provoke cancer and mutation in humans. Therefore, one of the important environmental issues is the effective removal of dyes from industrial wastewater. In the current work, BaFe12O19/CoFe2O4@polyethylene glycol (abbreviated as BFO/CFO@PEG) nanocomposite was synthesized and evaluated regarding its capacity for adsorptive removal of a model dye Acid Blue 92 (denoted as AB92) from aqueous solutions. The characteristics of the prepared nanocomposite was determined by tests such as X-ray diffraction (XRD), scanning electron microscope (SEM), vibration sample magnetization (VSM), and Fourier transform infrared spectroscopy (FTIR). The effects of conditional parameters including pH (2–12), initial concentration of dye (20–100 mg/L), adsorbent dosage (0.02–0.1 g/L) and contact time (0-180 min) on the adsorption of dye were investigated and then optimized. The results indicated that with the increase of the adsorbent dosage from 0.02 to 0.1 g/L, the removal efficiency increased from 74.1% to 78.6%, and the adsorbed amount decreased from 148.25 to 31.44 mg/g. The maximum removal efficiency (77.54%) and adsorption capacity (31.02 mg/g) were observed at pH 2. Therefore, the general optimization conditions revealed that the maximum adsorption efficiency of dye was obtained in condition of initial concentration of 20 mg/L, contact time of 1 h and pH of solution equal 2. The adsorption isotherm and kinetic data were evaluated using a series of models. The pseudo-second order kinetic model and Freundlich isotherm model show the best fitting with experimental data with R2∼0.999.


2019 ◽  
Vol 6 (2) ◽  
pp. 81-88 ◽  
Author(s):  
Dariush Naghipour ◽  
Abdoliman Amouei ◽  
Kamran Taher Ghasemi ◽  
Kamran Taghavi

Background: Metoprolol (MTP) with its low biodegradability is one of the most dominant micropollutant in the effluent of wastewater treatment plants. The aim of this study was to investigate the removal of metoprolol from aqueous solutions by the activated carbon prepared from pine cones. Methods: The pine cones were activated using thermal activation method. Characteristics of the adsorbent were determined using Brunauer-Emmett-Teller (BET) and scanning electron microscopy (SEM). In this study, the influent of different parameters such as pH, contact time, initial concentrations of metoprolol, adsorbent dose, temperature, adsorption isotherms, and kinetics were investigated. Results: The maximum removal efficiency of MTP (89.2%) was obtained at pH=8.5, adsorbent dose=1.5 g, contact time=60 min, and initial concentration=50 mg/L. By increasing the adsorbent dose, the removal efficiency also increased, but the adsorption capacity decreased, however, by increasing the initial concentration, the removal efficiency decreased, but the adsorption capacity increased. The isotherm experimental data for metoprolol was best fitted using the Langmuir model, and kinetic data were better described by pseudo-second-order kinetic model. The thermodynamic study indicated that the adsorption of MTP by the adsorbent was feasible, spontaneous, and endothermic. Conclusion: MTP removal by the activated carbon prepared from pine cones showed that this natural adsorbent is appropriate for removal of metoprolol from aqueous solutions regarding cost, efficiency, and production method.


2017 ◽  
Vol 47 (2) ◽  
pp. 927 ◽  
Author(s):  
I.K. Georgiadis ◽  
A. Papadopoulos ◽  
A. Filippidis ◽  
A. Godelitsas ◽  
A. Tsirambides ◽  
...  

Raw bauxite from Klisoura mine (Prefecture of Fokida, Greece) containing 72 wt.% diaspore, 16 wt.% hematite, 6 wt.% quartz, 4 wt.% anatase and 2 wt.% calcite, has been used for the removal of malachite green dye from aqueous solutions. The batch type experiments were conducted with 10 ml of solution, at pH = pHZPC = 6.7 and contact time 1 h. The initial concentration of malachite green dye was 10 mg/l, the bauxite quantity was 0.02 g, 0.04 g, 0.06 g, 0.1 g and 0.2 g. The highest adsorption capacity achieved was 4.5 mg/g (90% removal) using 0.02 g bauxite. The removal capacity of raw bauxite is comparable to other non-conventional adsorbents, such as neem sawdust, sugar cane dust and cane root carbon.


Author(s):  
Fatin Aqilah Mohd Nasir ◽  
Nur Rabiatul Amierah Mohd Ariff ◽  
Nurul Adibah Mohd Lazif ◽  
Nur Amalin Afifah Burhanuddin ◽  
Sharon Fatinathan ◽  
...  

Chitosan (CHS) and chitosan-tripolyphosphate beads (CTTP) were used for the removal of Erythrosine dye in batch adsorption experiments. The initial pH, agitation period, and adsorbent dosage were studied to determine the influence of these parameters on the adsorption capacity of the beads. Based on the initial pH study, the adsorption capacity for both adsorbents were found to be at pH 6. As the initial pH was increased, the adsorption capacity reduced for both beads. Based on the agitation period study, the kinetics of the adsorption process was determined. It was found that both CHS and CTPP followed the pseudo-second-order kinetic model with the highest adsorption capacity were attained at 50 and 60 minutes, respectively. An additional parameter on the adsorbent dosage was studied for CTTP beads to further improve on the removal capacity. The optimum adsorbent dosage for CHS and CTTP was achieved at 0.05 g and 0.6 g, respectively. An isotherm study was carried out on Erythrosine dye at the concentration of 20 mg/L – 100 mg/L for CHS and 20 mg/L – 150 mg/L for CTPP. It was found that the experimental data for CHS fitted the monolayer Langmuir model. Meanwhile, CTPP favored the multilayer Freundlich model. The CTPP was found to be effective in adsorbing a high concentration of dye, whereby the percentage of removal obtained was 92.6 % at the initial concentration of 150 mg/L of Erythrosine. Meanwhile, for CHS, the percentage of removal attained was 90.0% at the initial concentration of 60 mg/L of Erythrosine.  


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