scholarly journals Separate As(V) from solution by mesoporous Y-Al binary oxide: batch experiments

2017 ◽  
Vol 77 (4) ◽  
pp. 871-879
Author(s):  
Hang Liu ◽  
Caiyun Han ◽  
Liu Yang ◽  
Dekun Liu ◽  
Yongming Luo
Keyword(s):  
Point Of Zero Charge ◽  
Molar Ratio ◽  
Maximum Adsorption Capacity ◽  
Impregnation Method ◽  
Batch Experiments ◽  
Adsorption Performance ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Adsorption Desorption

Abstract Contaminant arsenic(V) has been regarded as one of the top-priority pollutants to remove from water. In this contribution, different mesoporous Y-Al binary oxides were prepared by the wet impregnation method via varying the molar ratio of Y/Al in the range of 0.029 to 0.116. The manufactured materials were employed as adsorbent to separate arsenic(V) from water. The adsorbent was characterized by N2 adsorption–desorption isotherm, point of zero charge (PZC) and Fourier transform infrared (FT-IR). Furthermore, the effect of experimental parameters on adsorption performance was evaluated by batch experiments, including the molar ratio of Y/Al, adsorbent dosages and contact time, initial concentration, initial pH and temperature. The results indicated that the adsorbent presented an optimal adsorption performance for As(V) uptake when the molar ratio of Y/Al was 0.058. The obtained experimental data were best fitted by Langmuir isotherm and the maximum adsorption capacity was 60.93 mg/g at pH 6.6 ± 0.1. Additionally, according to the results of adsorption kinetics, it was pronounced that adsorption process was complied with pseudo-second-order model. The adsorption thermodynamic suggested that the adsorption of As(V) is endothermic and spontaneous natural. Moreover, based on the results of FT-IR, PZC and initial pH, it is demonstrated that ion-exchange and electrostatic interaction were the dominating adsorption mechanism.

scholarly journals Adsorption performance of Cd(II), Cr(III), Cu(II), Ni(II), Pb(II) and Zn(II) by aminated solution-blown polyacrylonitrile micro/nanofibers

2018 ◽  
Vol 2017 (2) ◽  
pp. 378-389 ◽  
Author(s):  
Huiqing Lou ◽  
Xianzhong Cao ◽  
Xin Yan ◽  
Lina Wang ◽  
Zengbin Chen
Keyword(s):  
Hydroxylamine Hydrochloride ◽  
Order Kinetic ◽  
Adsorption Performance ◽  
Removal Of Heavy Metals ◽  
Initial Ph ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Adsorption Desorption ◽  
Pan Fibers

Abstract In this work, we prepared amidoxime-functionalized polyacrylonitrile (APAN) micro/nanofibers by modifying solution-blown PAN fibers with hydroxylamine hydrochloride, and investigated the adsorption performance of the APAN fibers for Cd(II), Cr(III), Cu(II), Ni(II), Pb(II) and Zn(II) from aqueous solutions. Batch experiments and quantitative analysis were conducted considering initial pH and contact time as controlling parameters. The equilibrium data were better explained by the Langmuir model with maximum adsorption capacities of 185, 204, 105, 104, 345 and 91 mg/g for Cd(II), Cr(III), Cu(II), Ni(II), Pb(II) and Zn(II), respectively. The adsorption kinetics were found to follow the pseudo-second-order kinetic model. The calculated thermodynamic parameters demonstrated that the adsorption of metal ions onto APAN fibers is feasible, spontaneous and endothermic. The five adsorption–desorption cycle experiments showed that APAN micro/nanofiber adsorbent exhibits good reusability, and has a potential application for the removal of heavy metals from wastewater.

scholarly journals Brasil nut mesocarp (Bertholletia excels) as a Biomass Source for Activated Carbon Production: Correlation Between Thermal Treatment and Adsorption Performance

2021 ◽  
Vol 12 (4) ◽  
pp. 4584-4596
Keyword(s):  
Activated Carbon ◽  
Maximum Adsorption Capacity ◽  
Brazil Nut ◽  
Order Model ◽  
X Ray ◽  
Adsorption Performance ◽  
Carbon Production ◽  
Pseudo Second Order ◽  
Adsorption Desorption ◽  
Best Fit

The activated carbon investigated in this work was produced from the extractive residues of Brazil nut processing, more specifically from the mesocarp of the Amazonian fruit. The process was performed by muffle pyrolysis, with ZnCl2 impregnation, at 400 and 500 °C. All samples were characterized by X-ray diffractometry, thermogravimetry, CHNS elemental analysis, scanning electron microscopy, and adsorption/desorption of N2. The results were promissory, with 99% removal of methylene blue for the CA25 material, which has a surface area of 1236 m2 g-1, much higher than commercial coal (CAC, 618 m2 g-1). The adsorption kinetics best fit the pseudo-second-order model for all materials. The maximum adsorption capacity obtained was 195.3 mg g-1. Therefore, the extractive residue of Brazil nut has excellent potential for the development of activated carbon, which can be used effectively to mediate environmental contamination in a given aqueous medium.

A functionalized tannin-chitosan bentonite composite with superior adsorption capacity for Cr(VI)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Zhongmin Li ◽  
Peng Zou ◽  
Junzhou Yang ◽  
Miaoyang Huang ◽  
Linye Zhang ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Raw Materials ◽  
Low Cost ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
Initial Ph ◽  
System Part ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Xrd Patterns

AbstractA novel functionalized tannin-chitosan bentonite composite (TCBC) was successfully synthesized. The formation of the composite was confirmed by the X-ray diffraction (XRD) patterns and Fourier transform infrared spectroscopy (FT-IR) analysis. The pHpzc of TCBC was 3.38. The influences such as pH, dosage of TCBC, temperature and initial Cr(VI) concentration on adsorption capacity were investigated. The experimental data indicated that the almost saturated adsorption of the TCBC towards Cr(VI) in 100 min. The maximum adsorption capacity was 262.08 mg/g at 333 K with initial pH = 2.5. The adsorption kinetics of Cr(VI) on TCBC followed the pseudo-second-order kinetics model. The isothermal data were well described by the models of Langmuir, Freundlich and Temkin. The results revealed that the adsorption of Cr(VI) on TCBC existed comprehensive effects and mainly belong to the chemisorption. The TCBC could keep good performances (qe = 192.17 mg/g) in five runs, 1 M NaOH was used as eluent for desorption, which showed a high desorption efficiency. Studies showed TCBC prepared with low cost and green raw materials, and simple green preparation technology had high adsorption capacity, good reusability and acidic tolerance. By exploring the Cr(VI)-Cr(III) hybrid system, part of Cr(VI) was reduced to Cr(III) and adsorbed by TCBC. The optimal adsorption pH of Cr(III) was 5.0.

scholarly journals Functionalization of Fe3O4/SiO2 with N-(2-Aminoethyl)-3-aminopropyl for Sorption of [AuCl4]-

2018 ◽  
Vol 16 (2) ◽  
pp. 130 ◽  
Author(s):  
Nuryono Nuryono ◽  
Mighfar Syukur ◽  
Agus Kuncaka ◽  
Satya Candra Wibawa Sakti
Keyword(s):  
Homogeneous System ◽  
Maximum Adsorption Capacity ◽  
Order Model ◽  
Transmission Electron ◽  
Coating Method ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Adsorption Desorption ◽  
Aminopropyl Group

Synthesis of Fe3O4/SiO2 modified with N-(2-aminoethyl)-3-aminopropyl group (Fe3O4/SiO2/ED) via coating method and its application for adsorption-desorption of anionic gold in aqueous solution have been conducted. The synthesized product was characterized with an X-ray diffractometer (XRD), a Fourier transform infrared (FT-IR) spectrophotometer and a transmission electron microscopy (TEM). Adsorption of Au(III) was conducted in a batch system and the variables included pH, contact time, and initial concentration were investigated. Results showed that magnetite/silica has been successfully functionalized with N-(2-aminoethyl)-3-aminopropyl in a homogeneous system. Kinetics study showed that adsorption of Au(III) followed the pseudo-second order model with rate constant of 0.710 g mmol L-1min-1. Furthermore, the experimental data fitted well with the Langmuir isotherm model with the maximum adsorption capacity for Au(III) of 142.9 mg g-1 and the energy of 25.0 kJ mol-1. Gold loaded on the Fe3O4/SiO2/ED could be easily desorbed with 0.2 mol L-1 HCl containing 2 wt.% of thiourea with recovery of 99.8%. Fe3O4/SiO2/ED was reusable and stable in 5 cycles of adsorption-desorption with recovery more than 90%. Fe3O4/SiO2/ED showed high selectivity towards Au(III) in the multimetal system Au(III)/Cu(II)/Cr(VI) with the coefficient selectivity for αAu-Cu of 227.5and for αAu-Cr of 12.3.

scholarly journals Facile Co-precipitation Synthesis of Nanosized MnFe2O4 for Effective Removal of Zn(II) Ions From Aqueous Media

2021 ◽  
Author(s):  
Ahmed Alharbi ◽  
Ahmad A. Alluhaybi ◽  
Salwa AlReshaidan ◽  
Hany M. Youssef
Keyword(s):  
Aqueous Media ◽  
Precipitation Method ◽  
Maximum Adsorption Capacity ◽  
Sem Image ◽  
Effective Removal ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Co Precipitation ◽  
Average Size

Abstract In this work, the spinel nanosized MnFe2O4 (18.14 nm) was facilely synthesized through the co-precipitation method to study the removal of Zn(II) ions from aqueous media. The fabricated MnFe2O4 sample was characterized using VSM, XRD, HR-TEM, EDS, FE-SEM, and FT-IR analyses. The principal XRD peaks, which are ascribed to (4 4 0), (3 3 3), (4 2 2), (4 0 0), (2 2 2), (3 1 1), (2 2 0), and (1 1 1) crystal planes, prove the cubic assembly of nanosized manganese ferrite as shown from JCPDS No. 74-2403. The EDS pattern confirmed that the % Wt of Mn, Fe, and O is 24.12, 48.04, and 28.15, respectively. The FE-SEM image confirmed the cubic nature of the surface of MnFe2O4 nanoparticles which have an average size of 110 nm. The saturation magnetization was 65 emu/g. The impacts of initial pH, concentration of Zn(II) ions, contact time, and temperature on the uptake of Zn(II) ions were accurately investigated. The removal of Zn(II) ions is spontaneous, exothermic, and followed the pseudo-second-order model and the Langmuir isotherm. The maximum adsorption capacity equals 330.03 mg/g.

Enhancement of the adsorption properties of two natural bentonites by ion exchange: equilibrium, kinetics and thermodynamic study

Clay Minerals ◽  
2020 ◽  
Vol 55 (2) ◽  
pp. 132-141
Author(s):  
Ali Boukhemkhem ◽  
Alejandro H. Pizarro ◽  
Carmen B. Molina
Keyword(s):  
Ion Exchange ◽  
Point Of Zero Charge ◽  
Exchange Equilibrium ◽  
Anionic Dyes ◽  
X Ray ◽  
Intraparticle Diffusion Model ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Bentonite Clays ◽  
Adsorption Desorption

ABSTRACTIn this investigation, Maghnia (Ma) and Mostaganem (Ms) bentonite clays, mined from west Algeria, with no prior affinity for anionic dyes, were modified by simple ion exchange with aqueous Fe3+ solutions, followed by calcination at 500°C. The resulting materials, Fe-Ma and Fe-Ms, respectively, were employed as adsorbents for methyl orange. The starting materials and the two adsorbents were characterized by X-ray diffraction, N2 adsorption–desorption isotherms, Brunauer–Emmett–Teller specific surface area and X-ray fluorescence and by determining the point of zero charge. The effects of various variables, such as initial dye concentration, contact time, adsorbent dose, initial pH and adsorption temperature, were studied. The kinetics were well described by the pseudo-second-order model and the mechanism was determined from the intraparticle diffusion model, while corresponding isotherms fitted better to the Freundlich model. Thermodynamic parameters showed that the adsorption process was endothermic, spontaneous and physical in nature, accompanied by an increase of entropy.

scholarly journals The Construction of Magnetic MnFe2O4@TpPa-1 Composite Materials and the Adsorption Removal Performance of Organic Pollutants in Solution

2021 ◽  
Vol 20 (4) ◽  
Author(s):  
Shuai Wang ◽  
Huifang Wang ◽  
Luzeng Hu ◽  
Zhipeng Lu ◽  
Muqing Qiu ◽  
...  
Keyword(s):  
Adsorption Mechanism ◽  
Adsorption Process ◽  
Regeneration Ability ◽  
Maximum Adsorption Capacity ◽  
Adsorption Removal ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Supporting Material ◽  
Co Precipitation ◽  
Adsorption Desorption

MnFe2O4@TpPa-1 adsorbent was developed by co-precipitation and solvothermal method, using ?-ketoenamine linked covalent organic frameworks (COFs, TpPa-1) as supporting material to alleviate the aggregation of MnFe2O4. The properties were characterized by XRD, FT-IR, SEM, TEM, VSM, pHpzc, and N2 adsorption-desorption. The experimental results showed that the pseudo-second-order and Langmuir model best described the adsorption process, suggesting that the adsorption process was chemisorption and spontaneous endothermic reaction, and the maximum adsorption capacity of Bisphenol A (BPA) was 926.65 mg.g-1. The main adsorption mechanism of BPA was hydrogen bonding and ?-? conjugation between active functional groups in the TpPa-1 skeleton and BPA. Furthermore, the magnetic MnFe2O4@TpPa-1 showed good regeneration ability, indicating that MnFe2O4@TpPa-1 could be used in water treatment.

Efficient adsorption of chlorpyrifos onto modified activated carbon by gamma irradiation; a plausible adsorption mechanism

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed S. Yahia ◽  
Ahmed S. Elzaref ◽  
Magdy B. Awad ◽  
Ahmed M. Tony ◽  
Ahmed S. Elfeky
Keyword(s):  
Gamma Irradiation ◽  
Area Measurement ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Pseudo First Order ◽  
Kinetics Of

Abstract Commercial Granulated Active Carbon (GAC) has been modified using 10 Gy dose Gamma irradiation (GAC10 Gy) for increasing its ability of air purification. Both, the raw and treated samples were applied for removing Chlorpyrifos pesticide (CPF) from ambient midair. Physicochemical properties of the two materials were characterized by Fourier Transform Infrared (FT-IR) and Raman spectroscopy. The phase formation and microstructure were monitored using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), supported with Energy-Dispersive X-ray (EDX). The Surface area measurement was detected using BET particle size prosometry. Obtained outcomes showed that, the maximum adsorption capacity, given by Langmuir equations, was greatly increased from 172.712 to 272.480 mg/g for GAC and GAC10 Gy, respectively, with high selectivity. The overall removal efficiency of GAC10 Gy was notably comparable to that of the original GAC-sorbent. The present study indicated that, gamma irradiation could be a promising technique for treating GAC and turned it more active in eliminating the pesticides pollutants from surrounding air. The data of equilibrium has been analyzed by Langmuir and Freundlich models, that were considerably better suited for the investigated materials than other models. The process kinetics of CPF adsorbed onto both tested carbon versions were found to obey the pseudo first order at all concentrations with an exception at 70 mg/l using GAC, where, the spontaneous exothermic adsorption of Chlorpyrifos is a strong function for the pseudo-first order (PFO) and pseudo second order (PSO) kinetics.

scholarly journals Biochar of Spent Coffee Grounds as Per Se and Impregnated with TiO2: Promising Waste-Derived Adsorbents for Balofloxacin

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2295
Author(s):  
Marwa El-Azazy ◽  
Ahmed S. El-Shafie ◽  
Hagar Morsy
Keyword(s):  
Adsorption Capacity ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Spent Coffee Grounds ◽  
Thermal Stabilities ◽  
Coffee Grounds ◽  
Bet Analysis ◽  
Pseudo Second Order ◽  
Set Up ◽  
Adsorption Desorption

Biochars (BC) of spent coffee grounds, both pristine (SCBC) and impregnated with titanium oxide (TiO2@SCBC) were exploited as environmentally friendly and economical sorbents for the fluroquinolone antibiotic balofloxacin (BALX). Surface morphology, functional moieties, and thermal stabilities of both adsorbents were scrutinized using SEM, EDS, TEM, BET, FTIR, Raman, and TG/dT analyses. BET analysis indicated that the impregnation with TiO2 has increased the surface area (50.54 m2/g) and decreased the pore size and volume. Batch adsorption experiments were completed in lights of the experimental set-up of Plackett-Burman design (PBD). Two responses were maximized; the % removal (%R) and the adsorption capacity (qe, mg/g) as a function of four variables: pH, adsorbent dosage (AD), BALX concentration ([BALX]), and contact time (CT). %R of 68.34% and 91.78% were accomplished using the pristine and TiO2@SCBC, respectively. Equilibrium isotherms indicated that Freundlich model was of a perfect fit for adsorption of BALX onto both adsorbents. Maximum adsorption capacity (qmax) of 142.55 mg/g for SCBC and 196.73 mg/g for the TiO2@SCBC. Kinetics of the adsorption process were best demonstrated using the pseudo-second order (PSO) model. The adsorption-desorption studies showed that both adsorbents could be restored with the adsorption efficiency being conserved up to 66.32% after the fifth cycles.

scholarly journals Insights into Starch Coated Nanozero Valent Iron-Graphene Composite for Cr(VI) Removal from Aqueous Medium

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Prasanna Kumarathilaka ◽  
Vimukthi Jayaweera ◽  
Hasintha Wijesekara ◽  
I. R. M. Kottegoda ◽  
S. R. D. Rosa ◽  
...  
Keyword(s):  
Point Of Zero Charge ◽  
Inert Material ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
X Ray Diffraction ◽  
Graphene Composite ◽  
Removal Capacity ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
First Time

Embedding nanoparticles into an inert material like graphene is a viable option since hybrid materials are more capable than those based on pure nanoparticulates for the removal of toxic pollutants. This study reports for the first time on Cr(VI) removal capacity of novel starch stabilized nanozero valent iron-graphene composite (NZVI-Gn) under different pHs, contact time, and initial concentrations. Starch coated NZVI-Gn composite was developed through borohydrate reduction method. The structure and surface of the composite were characterized by scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), and point of zero charge (pHpzc). The surface area and pHpzc of NZVI-Gn composite were reported as 525 m2 g−1 and 8.5, respectively. Highest Cr(VI) removal was achieved at pH 3, whereas 67.3% was removed within first few minutes and reached its equilibrium within 20 min obeying pseudo-second-order kinetic model, suggesting chemisorption as the rate limiting process. The partitioning of Cr(VI) at equilibrium is perfectly matched with Langmuir isotherm and maximum adsorption capacity of the NZVI-Gn composite is 143.28 mg g−1. Overall, these findings indicated that NZVI-Gn composite could be utilized as an efficient and magnetically separable adsorbent for removal of Cr(VI).

Sign in / Sign up

Export Citation Format

Share Document