Synthesis and characterization of a novel chloromethylated polystyrene-g-2-adenine chelating resin and its application to preconcentrate and detect the concentration of mercury ions in edible mushroom samples

2016 ◽  
Vol 94 (9) ◽  
pp. 751-758 ◽  
Author(s):  
Song Li ◽  
Yuping Feng ◽  
Lei Fang ◽  
Xuming Zheng ◽  
Desui Chen ◽  
...  

Edible mushrooms are widely usedtoday but the heavy metal pollution of edible mushrooms is not conducive to its industrialization. A novel chloromethylated polystyrene-g-2-adenine chelating resin (AR resin) with simple technology, high adsorption capacity, significant selectivity, and good regenerability was synthesized. Combined with the UV-Vis method, it was applied to mercury preconcentration and determination. The results indicated that the AR resin is essentially free from interferences, which can contribute to accurate determination in waters and foods. Optimization of the resin synthesis was carried out by using response surface methodology. The adsorption properties of the resin for Hg(II) were investigated by batch and column experiments. The statically and dynamic saturated adsorption capacities were 383.4 and 417.0 mg/g. The adsorption kinetic and equilibrium data were well fitted to the second-order model and the Langmuir isotherm model, respectively. Furthermore, the resin and its metal complexes were studied by Fourier transform infrared spectroscopy and thermogravimetric analysis.

2017 ◽  
Vol 76 (7) ◽  
pp. 1915-1924 ◽  
Author(s):  
Huihua Zhou ◽  
Jianjun Zheng ◽  
Hui Wang ◽  
Jianxin Wang ◽  
Xiaoguang Song ◽  
...  

With an efficient methodology, a novel chloromethylated polystyrene-g-2-mercapto-1,3,4-thiadiazole chelating resin (MTR resin) was prepared via a one-step reaction. The structure of MTR resin was characterized by elements analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. Meanwhile, the adsorption properties of the resin for Hg(II) were investigated by batch and column experiments. The results showed that the resin possessed much better adsorption capability for Hg(II) than for other metal ions. The statically and the dynamic saturated adsorption capacities were 343.8 mg/g and 475.1 mg/g. The adsorption kinetic and equilibrium data were well fitted to the second-order model and the Langmuir isotherm model, respectively. Desorption of mercury from the resin can be achieved using 30 mL of 2 mol/L HCl-5% thiourea solution with a desorption ratio of 92.3%. Compared with other absorbents, MTR resin was greatly conserve natural resources and reduce the cost.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hakan Çelebi ◽  
Gülden Gök ◽  
Oğuzhan Gök

Abstract Recently, the search for low-cost eco-friendly adsorbents has become one of the main objectives of researchers. The aim of this study was to test the removal of four heavy metals, namely lead (Pb), zinc (Zn), nickel (Ni) and cadmium (Cd), from a simulated watery solution using brewed tea waste as a potentially suitable adsorbent. The effects of pH levels (2.0–6.0), adsorbent amount (0.1–5.0 g), contact times (1–150 min.) were examined throughout the adsorption process. The results of the experiments showed that the heavy metals elimination yields had an inverse relationship with pH and a linear relationship between the other parameters. The optimum pH for the removal of the heavy metals was between 4.0 and 5.0 in the case of the brewed tea waste. Equilibrium times of 2, 10, 30 and 5 min were required for the adsorption of Pb, Zn, Ni, Cd onto Camellia sinensis, respectively. Based on the results of this study it can be said that brewed tea waste has a high potential to remove heavy metals from aqueous solutions. The maximum adsorption capacities were calculated as 1.197, 1.457, 1.163 and 2.468 mg/g, for Pb, Zn, Ni and Cd, respectively, by fitting the equilibrium data to the Langmuir isotherm model.


2011 ◽  
Vol 393-395 ◽  
pp. 1098-1101 ◽  
Author(s):  
Yan Yu ◽  
Feng Yuan Huang

In the present paper, the ability of carboxymethylcellulose sulfate (CMC-S) for Cu(II) removal was studied. The influence of factors, such as the pH value, the initial copper concentrations, and the contact time, were investigated in detail. Atomic absorption spectrophotometer was applied to determined the concentration of Cu(II). The results showed that the adsorption process was strongly dependent on the pH value and the initial copper concentration. The optimum pH value was in the range of 6-7. The theoretical adsorption capacities for Cu(II) was 127.7 mg/g. The equilibrium data was well fitted to the Langmuir isotherm model at 25°C, which can be explained as a monolayer adsorption.


2018 ◽  
Vol 156 ◽  
pp. 03014
Author(s):  
Sudarat Sertsing ◽  
Thanaphat Chukeaw ◽  
Sitthiphong Pengpanich ◽  
Bawornpong Pornchuti

In this study, silica aerogel was synthesized by drying at atmospheric pressure and modified further with aminopropyl triethoxysilane (APTES). The amine-functionalized silica aerogel was investigated as an adsorbent for removal of nickel and chromium ions. The effect of contact time, solution pH, and initial solution concentration were studied. The equilibrium was achieved within 60 min. The optimum pH was found to be 4. Adsorption equilibrium data were agreed fairly well with Langmuir isotherm model. Adsorption capacities for nickel and chromium ions were found to be 40.32 mg/g and 46.08 mg/g, respectively.


2012 ◽  
Vol 27 ◽  
pp. 107-114
Author(s):  
Jagjit Kour ◽  
P. L. Homagai ◽  
M. R. Pokherel ◽  
K. N. Ghimire

The industrial discharge of heavy metals into waters' course is one of the major pollution problems affecting water quality. Therefore, they must be removed prior to their discharge into waste streams. An efficient and low-cost bioadsorbent has been investigated from Desmostachya bipinnata (Kush) by charring with concentrated sulphuric acid and functionalized with dimethylamine.It was characterised by SEM, FTIR and elemental analysis. The effect of pH, initial concentration and contact time of the metal solution was monitered by batch method. The maximum adsorption capacities were determined for Cd and Zn at their optimum pH 6. The equilibrium data were analysed using Langmuir and Freundlich isotherm models. Langmuir isotherm model fitted well and the rate of adsorption followed the pseudo second order kinetic equation.DOI: http://dx.doi.org/10.3126/jncs.v27i1.6669 J. Nepal Chem. Soc., Vol. 27, 2011 107-114  


2021 ◽  
Author(s):  
Zhiyu Huang ◽  
Peng Wu ◽  
Yankun Yin ◽  
Xiang Zhou ◽  
Lu Fu ◽  
...  

Abstract In order to prepare low-cost and environmentally friendly adsorbent materials for adsorption of heavy metal ion, two kinds of novel modified cottons (C-4-APD and C-2-APZ) were obtained by introducing 4-aminopyridin and 2-aminopyrazine into the surface of degreasing cotton, respectively, and used for the removal of Cr(VI) ions from aqueous solution. The two modified cottons were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), which confirmed the amino groups, pyridine groups and pyrazine groups grafted onto the surface of modified cottons. The maximum adsorption capacities of C-4-APD and C-2-APZ were 73.78 mg/g and 61.34 mg/g, respectively, at the optimum pH of 6 and an initial concentration of 200 mg/g. Kinetic and isotherm studies were carried out to investigate the adsorption behavior of the modified cottons on Cr(VI) ions. The results showed that the adsorption of Cr(VI) ions by modified cottons followed a pseudo-second-order kinetic model, the equilibrium data were in good agreement with the Langmuir isotherm model, and electrostatic and chemisorption may be the main adsorption mechanisms. The recovery and reuse of modified cotton were achieved by washing with 2 wt% thiourea-hydrochloric acid solution (0.5 mol/L concentration of HCl), and the adsorption capacities of C-4-APD and C-2-APZ were maintained above 90% and 80%, respectively, after six cycles.


Author(s):  
Syed Rehan Ullah ◽  
Erum Zahir ◽  
Muhammad Asghar

In this study, the raw seashells of Mactra aequisulcata, of class Bivalvia and phylum Mollusca were employed as an adsorbent to remove copper (II) and cadmium (II) metal ions from aqueous solution. The characterization of shells was performed using FTIR, EDX and SEM, BET isotherm and point of zero charge (pHpzc). Batch experiments were performed to assess various factors on the biosorption efficiency. Maximum adsorption of both metals ions conveniently found at 0.4 g L-1 adsorbent dose, pH 5 and at 303 K. Maximum biosorption capacities for Cu2+ and Cd2+ were 59.57 and 38.12 mg g-1, respectively. The Langmuir isotherm model was found to be the best fit for the acquired equilibrium data. Thermodynamic and kinetic parameters presented that the process was feasible, exothermic and followed pseudo-first order.


Author(s):  
Maria Rosaria Boni ◽  
Agostina Chiavola ◽  
Simone Marzeddu

The BIOTON® biochar, produced by a wood biomass pyrolysis process, usually applied as a soil amendment, was investigated for a novel application, i.e. the adsorption of lead from contaminated solutions. The experimental activity firstly included the physical-chemical characterization of BIOTON®; SEM images were also obtained to highlight its internal structure. The adsorption process was investigated through batch and column experiments. Adsorption kinetics showed a very rapid achievement of the equilibrium conditions, i.e. at 2h and 4h for 50 mg/L and 100 mg/L initial Pb concentration, respectively. Complete removal also occurred within the same time. The Brunauer–Emmett–Teller model better fitted the equilibrium data for both Pb concentrations, whereas the kinetics were best represented by the pseudo second order model. The column tests showed that the addition of biochar as adsorbent media within the bed significantly extended the time of breakthrough and exhaustion, with respect to the column filled with soil only. The adsorption capacities of BIOTON® versus lead solutions was found to be comparable to that reported for commercial adsorbents. Therefore, BIOTON® can be considered a valid option, with the additional benefit to reduce the environmental impact since allows to recover a residue which alternately would need to be disposed of.


Author(s):  
Amal Benhathat ◽  
Moussa Amrani

In this paper, the synthesis and characterization of Ampelodesmos mauritanicus stems activated carbon (AMSAC) were studied. The produced activated carbon by phosphoric acid activation followed carbonisation was characterized by N2 adsorption-desorption isotherm, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, and Fourier transform infrared (FTIR) spectroscopy. Sorption potential of AMSAC for the removal of methylene bleu from water was investigated. The experimental data found that AMSAC had high Brunauer-Emmett-Teller (BET) surface area of 1293 m2/g and abundant pores with specific volume of 1.23 m3/g. FTIR analysis reveals various functional groups on the surface of AMSAC which can be play an important role for the adsorption process. Langmuir isotherm model fitted well the equilibrium data for the methylene bleu comparing to the Freundlich isotherm model; the monolayer sorption capacity of AMSAC was found to be 411.8 mg/g at 25 °C


2020 ◽  
Vol 22 (3) ◽  
pp. 221-233
Author(s):  
Khwanta Kaewnarin ◽  
Nakarin Suwannarach ◽  
Jaturong Kumla ◽  
Sadabpong Choonpicharn ◽  
Keerati Tanreuan ◽  
...  

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