scholarly journals Preparation of Poly(glycidyl methacrylate) (PGMA) and Amine Modified PGMA Adsorbents for Purification of Glucosinolates from Cruciferous Plants

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3286
Author(s):  
Li Cheng ◽  
Jianpeng Wu ◽  
Hao Liang ◽  
Qipeng Yuan

Glucosinolates (GLs) are of great interest for their potential as antioxidant and anticancer compounds. In this study, macroporous crosslinked copolymer adsorbents of poly (glycidyl methacrylate) (PGMA) and its amine (ethylenediamine, diethylamine, triethylamine)-modified derivatives were prepared and used to purify the GLS glucoerucin in a crude extract obtained from a cruciferous plant. These four adsorbents were evaluated by comparing their adsorption/desorption and decolorization performance for the purification of glucoerucin from crude plant extracts. According to the results, the strongly basic triethylamine modified PGMA (PGMA-III) adsorbent showed the best adsorption and desorption capacity of glucoerucin, and its adsorption data was a good fit to the Freundlich isotherm model and pseudo-second-order kinetics; the PGMA adsorbent gave the optimum decolorization performance. Furthermore, dynamic adsorption/desorption experiments were carried out to optimize the purification process. Two glass columns were serially connected and respectively wet-packed with PGMA and PGMA-III adsorbents so that glucoerucin could be decolorized and isolated from crude extracts in one process. Compared with KCl solution, aqueous ammonia was a preferable desorption solvent for the purification of glucoerucin and overcame the challenges of desalination efficiency, residual methanol and high operation costs. The results showed that after desorption with 10% aqueous ammonia, the purity of isolated glucoerucin was 74.39% with a recovery of 80.63%; after decolorization with PGMA adsorbent, the appearance of glucoerucin was improved and the purity increased by 11.30%. The process of using serially connected glass columns, wet-packed with PGMA and PGMA-III, may provide a simple, low-cost, and efficient method for the purification of GLs from cruciferous plants.

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2586
Author(s):  
Inas A. Ahmed ◽  
Ahmed H. Ragab ◽  
Mohamed A. Habila ◽  
Taghrid S. Alomar ◽  
Enas H. Aljuhani

In this work, low-cost and readily available limestone was converted into nanolimestone chitosan and mixed with alginate powder and precipitate to form a triple nanocomposite, namely limestone—chitosan–alginate (NLS/Cs/Alg.), which was used as an adsorbent for the removal of brilliant green (BG) and Congo red (CR) dyes in aqueous solutions. The adsorption studies were conducted under varying parameters, including contact time, temperature, concentration, and pH. The NLS/Cs/Alg. was characterized by SEM, FTIR, BET, and TEM techniques. The SEM images revealed that the NLS/Cs/Alg. surface structure had interconnected pores, which could easily trap the pollutants. The BET analysis established the surface area to be 20.45 m2/g. The recorded maximum experimental adsorption capacities were 2250 and 2020 mg/g for CR and BG, respectively. The adsorption processes had a good fit to the kinetic pseudo second order, which suggests that the removal mechanism was controlled by physical adsorption. The CR and BG equilibrium data had a good fit for the Freundlich isotherm, suggesting that adsorption processes occurred on the heterogeneous surface with a multilayer formation on the NLS/Cs/Alg. at equilibrium. The enthalpy change (ΔH0) was 37.7 KJ mol−1 for CR and 8.71 KJ mol−1 for BG, while the entropy change (ΔS0) was 89.1 J K−1 mol−1 for CR and 79.1 J K−1 mol−1 BG, indicating that the adsorption process was endothermic and spontaneous in nature.


Author(s):  
Qintao Yang ◽  
Liang Gong ◽  
Lili Huang ◽  
Qinglin Xie ◽  
Yijian Zhong ◽  
...  

A novel chitosan (CS)-modified diatomite (Dt) was prepared by a simple mixture in the mass ratio to remove As(V) from aqueous solution in this research. The CS-modified Dt adsorbent was characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray powder diffraction (XRD) analysis. The parameters to influence the adsorption of As(V) ion were studied under such conditions as kinetics, adsorption isotherm, and pH effect. The results revealed that adsorption of As(V) was initially rapid and the equilibrium time was reached after 40 min. The optimal value of the pH was 5.0 for better adsorption. The equilibrium data were well fitted to the Langmuir isotherm compared to the Freundlich isotherm, and exhibited the highest capacity and removal efficiency of 94.3% under an initial As(V) concentration of 5 mg/L. The kinetic data were well described by the pseudo-second-order model. In addition, 0.1 M NaOH has the best desorption efficiency of As(V) adsorbed on CS-modified Dt, and the removal efficiency of As(V) was still higher than 90% when after six adsorption-desorption cycles. These results showed that the CS-modified Dt could be considered as a potential adsorbent for the removal of As(V) in aqueous solution.


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.


2021 ◽  
Author(s):  
Samina Zaman ◽  
Md. Nayeem Mehrab ◽  
Md. Shahnul Islam ◽  
Gopal Chandra Ghosh ◽  
Tapos Kumar Chakraborty

Abstract This study investigates the potential applicability of hen feather (HF) to remove methyl red (MR) dye from aqueous solution with the variation of experimental conditions: contact time (1–180 min), pH (4–8), initial dye concentration (5–50 mg/L) and adsorbent dose (3–25 g/L). Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) evaluate the surface morphology and chemistry of HF, respectively. The maximum removal of MR by HF was 92% when the optimum conditions were initial MR dye concentration 05 mg/L, pH 4.0, adsorbent dose 07.0 g/L and 90.0 min equilibrium contact time. Langmuir isotherm (R2 = 0.98) was more suited than Freundlich isotherm (R2 = 0.96) for experimental data, and the highest monolayer adsorption capacity was 6.02 mg/g. The kinetics adsorption data fitted well to pseudo-second-order model (R2 = 0.999) and more than one process were involved during the adsorption mechanism but film diffusion was the potential rate-controlling step. The findings of the study show that HF is a very effective and low-cost adsorbent for removing MR dye from aqueous solutions.


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 ◽  
Vol 55 (7-8) ◽  
pp. 919-932
Author(s):  
HANEN NOURI ◽  
ASMA ABDEDAYEM ◽  
INES HAMIDI ◽  
SOUAD SOUISSI NAJJAR ◽  
ABDELMOTTALEB OUEDERNI

The potential of Tunisian prickly pear cactus as a low-cost adsorbent for Pb(II) ions from aqueous solution was investigated in batch mode. To determine the optimum adsorption conditions, experiments were conducted varying the operating parameters, as follows: pH of the solutions (2-10), initial concentration of metal ions (0.98-2.4 mmol/L) and temperature (30-60 °C). The adsorption isotherm data were analyzed by applying the Langmuir, Freundlich, Dubinin–Raduskevich, Temkin and Redlich–Peterson models. The experimental results were better fitted by the Freundlish model. The pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion models were applied to the description of the kinetic data. The best fit was achieved for the pseudo-second order model, and the presence of both film and intraparticle diffusion mechanisms was demonstrated. Thermodynamic studies indicated that the biosorption on the cladode powder is an exothermic and chemical process. The desorption/regeneration process was also investigated. The obtained results revealed over 90% desorption of Pb(II) metal ions from the total metal-loaded mass of the adsorbent and good stability of the cactus adsorbent for four successive adsorption/desorption cycles.


2019 ◽  
Vol 9 (2) ◽  
pp. 102-115
Author(s):  
Hanane Essebaai ◽  
Ilham Ismi ◽  
Ahmed Lebkiri ◽  
Said Marzak ◽  
El Housseine Rifi

Highly efficient low-cost adsorbent was applied for copper (II) ions uptake from aqueous solution. Characteristics of natural adsorbent were established using scanning X-ray diffraction (XRD), X-ray fluorescence, electron microscope (SEM) and Fourier Transform Infra-Red (FTIR). Various physicochemical parameters such as contact time, initial copper(II) ions concentration, adsorbent dosage, pH of copper (II) ions solution and temperature were investigated. The result showed that the adsorption of copper (II) ions by natural clay was favorable at pH=5,5. The adsorption was found to increase with increase in initial copper (II) ions concentration, and contact time. Equilibrium adsorption data were fitted using three isotherms and kinetic data tested with four kinetic models. Freundlich isotherm best described the adsorption of copper (II) ions onto utilised clay, the maximum monolayer adsorption capacity (qmax) was 8 mg/g. Pseudo-second-order model best described the kinetics of the adsorption process. Thermodynamic parameters such as Gibbs free energy, enthalpy and entropy were determined. It was found that copper (II) ions adsorption was spontaneous (ΔG°<0) and endothermic (ΔH°>0).


2015 ◽  
Vol 72 (9) ◽  
pp. 1505-1515 ◽  
Author(s):  
H. Asnaoui ◽  
A. Laaziri ◽  
M. Khalis

Batch experiments were conducted to study the adsorption of hazardous cadmium onto low-cost algae biomass in aqueous solution with respect to concentration of adsorbate, adsorbent dosage, contact time, solution pH and temperature. Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were determined. The activation energy of adsorption was also evaluated for the adsorption of cadmium onto Ulva lactuca biomass. Experimental data were tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of Cd(II) followed well pseudo-second-order kinetics. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the metal ions by Ulva lactuca biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The biosorption capacity of Ulva lactuca biomass for cadmium was found to be 3.02 mg/g at pH 5.60 min equilibrium time and 20 °C. The mean free energy which was calculated was 6.24 kJ/mol for Cd(II) biosorption, which shows that the adsorption is physical. The calculated thermodynamic parameters (ΔG0, ΔH0 and ΔS0) showed that the biosorption of Cd(II) onto Ulva lactuca biomass was feasible, spontaneous and exothermic under examined conditions. The results indicate that algae Ulva lactuca could be employed as a low-cost material for the removal of metal ions from aqueous solution.


2016 ◽  
Vol 75 (5) ◽  
pp. 1051-1058 ◽  
Author(s):  
Qiujin Jia ◽  
Wanting Zhang ◽  
Dongping Li ◽  
Yulong Liu ◽  
Yuju Che ◽  
...  

Hydrazinolyzed cellulose-graft-polymethyl acrylate (Cell-g-PMA-HZ), an efficient adsorbent for removal of Cd(II) and Pb(II) from aqueous solution, has been prepared by ceric salt-initiated graft polymerization of methyl acrylate from microcrystalline cellulose surface and subsequent hydrazinolysis. The influences of initial pH, contact time, and temperature on adsorption capacity of Cell-g-PMA-HZ as well as adsorption equilibrium, kinetic and thermodynamic properties were examined in detail. As for Cd(II) adsorption, kinetic adsorption can be explained by pseudo-second-order, while adsorption isotherm fits well with Langmuir isotherm model, from which maximum equilibrium adsorption capacity can be derived as 235.85 mg g−1 at 28 °C. Further thermodynamic investigation indicated that adsorption of Cd(II) by adsorbent Cell-g-PMA-HZ is endothermic and spontaneous under studied conditions. On the other hand, isotherm of Pb(II) adsorption fits well with Freundlich isotherm model and is more likely to be a physical-adsorption-dominated process. Consecutive adsorption–desorption experiments showed that Cell-g-PMA-HZ is reusable with satisfactory adsorption capacity.


Author(s):  
Donald T. Kukwa ◽  
Peter A. Adie ◽  
Rose E. Kukwa ◽  
Paula D. Kungur

Removal of Pb (II) ion from aqueous solution using Hymenoptera sphecidae (mud-wasp) nest was investigated using a batch process. The effect of pH, contact time and adsorbent dose were also investigated. The result showed that the adsorption of Pb (II) ion onto mud-wasp nest was dependent on pH, contact time and adsorbent dose. Adsorption patterns were analysed in terms of three bi-parameter isotherms of Langmuir, Freundlich and Temkin. Freundlich isotherm gave the best fit to the adsorption data with a correlation coefficient of 0.992, while monolayer sorption capacity yielded 41.667 mg/g. Lagergren’s pseudo first-order and pseudo second-order kinetic models were used to test the adsorption kinetics. The kinetic data were well described by the pseudo second-order kinetic model, suggesting that the process was chemisorption type.  The results showed that mud-wasp nest can be used as a low-cost adsorbent for the removal of Pb (II) ion from aqueous solutions.


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