Removing Cd(II) from Aqueous Solution by Inverse Opal Hybrid SiO2

A hybrid adsorbent with inverse opal (IO) structure was prepared for removing Cd(II) from aqueous solution. The functional polymeric chains were grafted from the pore wall of IO silica to prepare the porous hybrid material by surface-initiated atom-transfer radical polymerization. Furthermore, the amidation reaction was carried out to obtain diethylenetriamine-modified hybrid adsorbent (IO SiO2-g-PAA-DETA). Batch adsorption of removing Cd(II) onto IO SiO2-g-PAA-DETA was studied as the effect of solution pH, adsorbent doses, contact time, ionic concentration, and temperature. When the grafted amount was 73%, the maximum adsorption capacity was obtained. The optimum adsorbent dose and pH value for adsorbing Cd(II) were found to be 5[Formula: see text]g/L and 0.5[Formula: see text]g/L, respectively. The adsorption capacity was almost unaffected by Na[Formula: see text] at low concentrations. The adsorption data was depicted by the corresponding models and the results displayed that adsorbing Cd(II) on IO SiO2-g-PAA-DETA followed the Freundlich and pseudo-first-order model. In addition, after six adsorption–desorption cycles, IO adsorbent could remain above 80% of the first adsorption ability while it was washed using 0.025[Formula: see text]M EDTA.

Download Full-text

Adsorption of Pb2+ ions from aqueous solutions by gelatin/activated carbon composite bead form

Adsorption Science & Technology ◽

10.1177/0263617417693006 ◽

2017 ◽

Vol 36 (1-2) ◽

pp. 355-371 ◽

Cited By ~ 6

Author(s):

Fareeda Hayeeye ◽

Qiming J Yu ◽

Memoon Sattar ◽

Watchanida Chinpa ◽

Orawan Sirichote

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Ph Value ◽

Carbon Composite ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Experimental Conditions ◽

Composite Bead

Gelatin and activated carbon materials have been combined together to obtain a gelatin/activated carbon composite bead form which is ecofriendly, nontoxic, biocompatible, and inexpensive material. In this paper, gelatin/activated carbon adsorption for Pb2+ ions from aqueous solutions was studied experimentally under various conditions. The experimental conditions such as contact time, solution pH, and gelatin/activated carbon dosage were examined and evaluated by using batch adsorption experiments. The maximum adsorption capacity of gelatin/activated carbon for Pb2+ ions was obtained to be 370.37 mg g−1. This maximum capacity was comparable with that of commercial ion exchange resins and it was much higher than those of natural zeolites. The uptake process for Pb2+ ions was found to be relatively fast with 92.15% of the adsorption completed in about 5 min in batch conditions. The adsorption capacity was also strongly solution pH dependent. Adsorption was observed at pH value as low as 2.0 and maximum adsorption was achieved at a pH of approximately 5. The results indicated that the gelatin/activated carbon was effective to be used as an adsorbent for Pb2+ ions removal in wastewater treatment.

Download Full-text

Influence of Magnetic Nanoparticles on Modified Polypyrrole/m-Phenylediamine for Adsorption of Cr(VI) from Aqueous Solution

Polymers ◽

10.3390/polym12030679 ◽

2020 ◽

Vol 12 (3) ◽

pp. 679 ◽

Cited By ~ 8

Author(s):

Thabiso Carol Maponya ◽

Kabelo Edmond Ramohlola ◽

Nazia Hassan Kera ◽

Kwena Desmond Modibane ◽

Arjun Maity ◽

...

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Entropy Change ◽

Significant Loss ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Transmission Electron ◽

Magnetite Fe3o4 ◽

Application Potential ◽

Adsorption Desorption

A novel, modified polypyrrole/m-phenylediamine (PPy–mPD) composite, decorated with magnetite (Fe3O4) nanoparticles, and prepared via an in-situ oxidative polymerisation, was investigated. The PPy–mPD/Fe3O4 nanocomposite was employed for the removal of highly toxic oxyanion hexavalent chromium Cr(VI) from an aqueous solution. The structure and successful formation of the PPy–mPD/Fe3O4 nanocomposite was confirmed and investigated using various techniques. The presence of Fe3O4 was confirmed by high resolution transmission electron microscopy, with an appearance of Fe lattice fringes. The estimation of the saturation magnetisation of the nanocomposite, using a vibrating sample magnetometer, was observed to be 6.6 emu/g. In batch adsorption experiments, PPy–mPD/Fe3O4 nanocomposite (25 mg) was able to remove 99.6% of 100 mg/L of Cr(VI) at pH 2 and 25 °C. Adsorption isotherms were investigated at different Cr(VI) concentration (100–600 mg/L) and temperature (15–45 °C). It was deduced that adsorption follows the Langmuir model, with a maximum adsorption capacity of 555.6 mg/g for Cr(VI) removal. Furthermore, isotherm data were used to calculate thermodynamic values for Gibbs free energy, enthalpy change and entropy change, which indicated that Cr(VI) adsorption was spontaneous and endothermic in nature. Adsorption–desorption experiments revealed that the nanocomposite was usable for two consecutive cycles with no significant loss of adsorption capacity. This research demonstrates the application potential for the fascinating properties of PPy–mPD/Fe3O4 nanocomposite as a highly efficient adsorbent for the removal of heavy metal ions from industrial wastewater.

Download Full-text

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

Molecules ◽

10.3390/molecules26082295 ◽

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.

Download Full-text

Removal of Cd(II) from Water System Using Novel Biosorbent Derived from Persimmon Fallen Leaves

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1130.685 ◽

2015 ◽

Vol 1130 ◽

pp. 685-688

Author(s):

Rui Yi Fan ◽

Qing Ping Yi ◽

Qing Lin Zhang ◽

Zheng Rong Luo

Keyword(s):

Aqueous Solution ◽

Metal Ions ◽

Adsorption Capacity ◽

Water System ◽

Raw Material ◽

Batch Adsorption ◽

Diospyros Kaki ◽

Cadmium Metal ◽

Fallen Leaves ◽

Adsorption Desorption

A biosorbent was prepared by treating the persimmon (Diospyros kaki Thunb.) fallen leaves with sodium hydroxide (NaOH). The NaOH concentration and stirring period for the preparation of the biosorbent were adjusted to optimise the Cd(I) adsorption capacity of the biosorbents. Removal of highly toxic Cadmium metal ions from water system using the optimal biosorbent named ‘NPFL’ was investigated using a mimic industrial column. The result showed that NPFL could remove Cd(II) in large quantities from aqueous solution with coexisting metal ions. The raw material, NPFL and Cd(II) loaded NPFL were characterized by SEM-EDS. The reusability of NPFL was also studied by batch adsorption-desorption test.

Download Full-text

Adsorption of hexavalent chromium by polyacrylonitrile-based porous carbon from aqueous solution

Royal Society Open Science ◽

10.1098/rsos.171662 ◽

2018 ◽

Vol 5 (1) ◽

pp. 171662 ◽

Cited By ~ 14

Author(s):

Bin Feng ◽

Wenzhong Shen ◽

Liyi Shi ◽

Shijie Qu

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Porous Carbon ◽

Photoelectron Spectroscopy ◽

Ph Value ◽

Functional Materials ◽

High Specific Surface Area ◽

Maximum Adsorption Capacity ◽

Elementary Analysis ◽

Initial Adsorption

Owing to the unique microporous structure and high specific surface area, porous carbon could act as a good carrier for functional materials. In this paper, polyacrylonitrile (PAN)-based porous carbon materials (PPC-0.6-600, PPC-0.8-600, PPC-0.6-800 and PPC-0.8-800) were prepared by heating KOH at 600°C and 800 o C for the removal of Cr(VI) from aqueous solution. The adsorbent was characterized by the techniques of Fourier transform infrared spectroscopy (FT-IR), elementary analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and N 2 adsorption techniques. The results showed that the adsorption capacity increased with decreasing pH value of the initial solution. The adsorption capacity of Cr(VI) on PPC-0.8-800 was much greater than that on other materials, and maximum adsorption capacity were calculated to be 374.90 mg g −1 . Moreover, PPC-0.8-800 had superior recyclability for the removal of Cr(VI) from wastewater, about 82% of its initial adsorption capacity was retained even after five cycles. The result of kinetic simulation showed that the adsorption of Cr(VI) on the PAN-based porous carbon could be described by pseudo-second-order kinetics. The adsorption process was the ionic interaction between protonated amine groups of PPC and HCrO 4 - ions.

Download Full-text

Efficient Removal of Diclofenac from Aqueous Solution by Potassium Ferrate-Activated Porous Graphitic Biochar: Ambient Condition Influences and Adsorption Mechanism

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17010291 ◽

2019 ◽

Vol 17 (1) ◽

pp. 291 ◽

Cited By ~ 6

Author(s):

Nguyen Thi Minh Tam ◽

Yunguo Liu ◽

Hassan Bashir ◽

Zhihong Yin ◽

Yuan He ◽

...

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Diclofenac Sodium ◽

Maximum Adsorption Capacity ◽

Potassium Ferrate ◽

Solution Ph ◽

Modified Biochar ◽

Prepared Material ◽

Endothermic Process ◽

One Step

Porous graphitic biochar was synthesized by one-step treatment biomass using potassium ferrate (K2FeO4) as activator for both carbonization and graphitization processes. The modified biochar (Fe@BC) was applied for the removal of diclofenac sodium (DCF) in an aqueous solution. The as-prepared material possesses a well-developed micro/mesoporous and graphitic structure, which can strengthen its adsorption capacity towards DCF. The experimental results indicated that the maximum adsorption capacity (qmax) of Fe@BC for DCF obtained from Langmuir isotherm simulation was 123.45 mg·L−1 and it was a remarkable value of DCF adsorption in comparison with that of other biomass-based adsorbents previously reported. Thermodynamic quality and effect of ionic strength studies demonstrated that the adsorption was a endothermic process, and higher environmental temperatures may be more favorable for the uptake of DCF onto Fe@BC surface; however, the presence of NaCl in the solution slightly obstructed DCF adsorption. Adsorption capacity was found to be decreased with the increase of solution pH. Additionally, the possible mechanism of the DCF adsorption process on Fe@BC may involve chemical adsorption with the presence of H-bonding and π–π interaction. With high adsorption capacity and reusability, Fe@BC was found to be a promising absorbent for DCF removal from water as well as for water purification applications.

Download Full-text

Selenate Adsorption from Water Using the Hydrous Iron Oxide-Impregnated Hybrid Polymer

Metals ◽

10.3390/met10121630 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1630

Author(s):

Vesna Marjanovic ◽

Aleksandra Peric-Grujic ◽

Mirjana Ristic ◽

Aleksandar Marinkovic ◽

Radmila Markovic ◽

...

Keyword(s):

Iron Oxide ◽

Adsorption Capacity ◽

Ph Value ◽

Xrd Analysis ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Adsorbent Regeneration ◽

Desorption Efficiency ◽

Hydrous Iron Oxide ◽

The Cross

Hybrid adsorbent, based on the cross-linked copolymer impregnated with hydrous iron oxide, was applied for the first time for Se(VI) adsorption from water. The influence of the initial solution pH, selenate concentration and contact time to adsorption capacity was investigated. Adsorbent regeneration was explored using a full factorial experimental design in order to optimize the volume, initial pH value and concentration of the applied NaCl solution as a reagent. Equilibrium state was described using the Langmuir model, while kinetics fitted the pseudo-first order. The maximum adsorption capacity was found to be 28.8 mg/g. Desorption efficiency increased up to 70%, and became statistically significant with the reagent concentration and pH increase, while the applied solution volume was found to be insignificant in the investigated range. Based on the results obtained, pH influence to the adsorption capacity, desorption efficiency, Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analysis of loaded adsorbent, it was concluded that the outer- and inner-sphere complexation are mechanisms responsible for Se(VI) separation from water. In addition to the experiments with synthetic solutions, the adsorbent performances in drinking water samples were explored, showing the purification efficiency up to 25%, depending on the initial Se(VI) concentration and water pH. Determined sorption capacity of the cross-linked copolymer impregnated with hydrous iron oxide and its ability for regeneration, candidate this material for further research, as a promising anionic species sorbent.

Download Full-text

Metal Adsorbent Prepared from Coir Pith as Agricultural Waste: Adsorption of Zn(II) and Pb(II) from Aqueous Solution

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.545.101 ◽

2013 ◽

Vol 545 ◽

pp. 101-108 ◽

Cited By ~ 1

Author(s):

Kitirote Wantala ◽

Nusavadee Pojananukij ◽

Pongsert Sriprom ◽

Tinnakorn Kumsaen ◽

Arthit Neramittagapong ◽

...

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Calcination Temperature ◽

Ph Value ◽

Agricultural Waste ◽

Initial Solution ◽

Order Kinetic ◽

Solution Ph ◽

Freundlich Isotherms ◽

Coir Pith

Adsorption of Zn(II) and Pb(II) from aqueous solution were studied by using modified coir pith as an adsorbent. The extended adsorption conditions were investigated as a function of calcination temperature, contact time, adsorbent size, initial pH of solution and initial Zn(II) and Pb(II) concentrations. The adsorption capacity increased rapidly in first 5 minute and reached equilibrium in 120 minutes for Zn(II) and 10 minutes for Pb(II). In case of Zn(II); the results showed that the calcination temperature of modified coir pith above 600oC gave the higher adsorption capacity. The sizes of modified coir pith have no effect on the adsorption capacity. The adsorption capacity increased with increasing initial solution pH value. In case of Pb(II); the calcination temperature of modified coir pith showed no effect on the adsorption capacity. The sizes of modified coir pith showed a little effect on the adsorption capacity. The adsorption capacity increased with increasing of initial solution pH value up to pH of 3 and then stable. The results also corresponded with the Langmuir and Freundlich isotherms and pseudo second order kinetic adsorption models. The modified coir pith gave a higher Zn(II) and Pb(II) adsorption capacity of 29.33 mg Zn(II)/g adsorbent and 36.50 mg Pb(II)/g adsorbent, respectively.

Download Full-text

Removal and Regeneration of Iron (III) from Water Using New Treated Fluorapatite Extracted from Natural Phosphate as Adsorbent

Biointerface Research in Applied Chemistry ◽

10.33263/briac115.1313013140 ◽

2021 ◽

Vol 11 (5) ◽

pp. 13130-13140

Keyword(s):

Adsorption Capacity ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

Solution Ph ◽

Natural Phosphate ◽

Dissolved Iron ◽

Naturally Occurring ◽

Ft Ir ◽

Adsorption Desorption ◽

Ft Ir Spectroscopy

Our study aims to evaluate the efficiency of dissolved iron (III) retention in synthetic solutions by adsorption on treated natural phosphate collected in the Khouribga region. This research focused on the valorization of phosphate, a naturally occurring resource that is abundant in Morocco. The resulting products were analyzed by various methods, including FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). In this work, we studied the effect of several parameters such as adsorbent amount, contact time, solution pH, and initial concentration of iron (III) on the adsorption process. The results of the adsorption of iron (III) indicate that the efficiency was achieved after 5 minutes, and the maximum adsorption capacity calculated from the Langmuir model was 26.18 mg g-1. The regeneration and reuse of synthesized adsorbent are effective for five cycles of adsorption-desorption cycles without reducing adsorption capacity.

Download Full-text

Cd(II) removal on surface-modified activated carbon: equilibrium, kinetics and mechanism

Water Science & Technology ◽

10.2166/wst.2016.338 ◽

2016 ◽

Vol 74 (8) ◽

pp. 1800-1808 ◽

Cited By ~ 6

Author(s):

Jianjun Liang ◽

Meiling Liu ◽

Yufei Zhang

Keyword(s):

Aqueous Solution ◽

Activated Carbon ◽

Adsorption Capacity ◽

Orthogonal Experiment ◽

Xrd Analysis ◽

Bet Surface Area ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Modified Activated Carbon ◽

Surface Modified

Commercial pulverous activated carbon (AC-0) was modified through two steps: oxidize AC-0 acid firstly, impregnate it with iron using ferric chloride secondly. Orthogonal experiment was conducted then to prepare modified activated carbon with high Cd(II) adsorption capacity (ACNF). Batch adsorption experiments were undertaken to determine the adsorption characteristics of Cd(II) from aqueous solution onto AC-0 and ACNF and the effect of pH, contact time and initial Cd(II) concentration. The results indicate that: the adsorption behavior of Cd(II) on ACNF can be well fitted with Langmuir model, and the maximum adsorption capacity of ACNF was 2.3 times higher than that of AC-0, supporting a monolayer coverage of Cd(II) on the surface. The kinetics of the adsorption process can be described by pseudo-second-order rate equation very well, and the adsorption capacity increased from 0.810 mg/g to 0.960 mg/g after modification. Compared with AC-0, the kinetic parameters of ACNF showed a higher adsorption rate through the aqueous solution to the solid surface and a lower intraparticle diffusion rate. Surface modification resulted in a lower Brunauer–Emmett–Teller (BET) surface area and pore size because of the collapse and blockage of pores, according to the X-ray diffraction (XRD) analysis, while the total number of surface oxygen acid groups increased, and this was supposed to contribute to the enhanced adsorption capacity of modified activated carbon.

Download Full-text