scholarly journals Extraction of Cellulose Polymeric Material from Populus tremula Fibers: Characterization and Application to the Adsorption of Methylene Blue and Crystal Violet

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3334
Author(s):  
Faisal Muteb Almutairi ◽  
Yassine El-Ghoul ◽  
Mahjoub Jabli

Cellulose is the most widely available biopolymer which is extensively used for several applications including textiles, composites, pharmaceutical, water treatment, etc. In this investigation, cellulose was chemically extracted from Populus tremula seed fibers. Samples were characterized using FT-IR, SEM, XRD, and TGA-DTA analyses. FT-IR spectrum of the extracted cellulose confirmed that hemicellulose and lignin were removed during alkali and bleaching treatments. SEM images showed the partially roughened surface of the fiber due to the removal of non-cellulosic elements and surface impurities during chemical modification. The crystallinity index values for untreated Populus tremula fibers and extracted cellulose were calculated to be 32.8% and 58.9%, respectively. The obvious increase in the crystallinity index for the extracted cellulose confirmed the removal of amorphous compounds present in raw populus. Alkali-treated populus fibers were more thermally stable than raw fibers. All changes observed after alkali and bleaching treatments evidenced the removal of amorphous contents and non-cellulosic components in raw populus fibers. Extracted cellulose exhibited excellent adsorption capacities of methylene blue (140.4 mg g−1) and crystal violet (154 mg g−1). The pseudo second order equation fitted well the kinetic data indicating a chemi-sorption process. The Freundlich model complied well with the experimental data suggesting that the adsorption of the studied dyes was multilayer.

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
H. Ait Ahsaine ◽  
Z. Anfar ◽  
M. Zbair ◽  
M. Ezahri ◽  
N. El Alem

Zirconium oxide/activated carbon (Zr3O/AC) composite was synthesized to remove methylene blue (MB) and crystal violet (CV) from the aqueous medium. The Zr3O/AC sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analyses (EDS), Raman spectroscopy (RS), BET surface area, and Fourier transform infrared spectroscopy (FTIR). XRD profiles confirmed the successful synthesis of the zirconium oxide/activated carbon composite. SEM images showed multideveloped walls with irregular particle size with channel arrays. The nitrogen physisorption combines I and IV types with a calculated BET surface area of 1095 m2/g. Raman spectrum illustrated a disorder of both crystalline structure and the graphitic structure. The adsorption was better fitted to the pseudo-second-order (PSO) kinetic model. Langmuir model fitted better the experimental results of MB adsorption, whereas the CV was better consistent with the Freundlich model. The obtained results suggested that the MB and CV adsorption might be influenced by the mass transfer that involves multiple diffusion steps. The maximum adsorption capacities are 208.33 and 204.12 mg/g for MB and CV, respectively. The MB and CV removal mechanisms were proposed, and statistical optimization was performed using central composite design combined with the response surface methodology.


Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3718
Author(s):  
Dorota Kołodyńska ◽  
Dominika Fila ◽  
Zbigniew Hubicki

The recovery of La(III) and Ni(II) ions by a macroporous cation exchanger in sodium form (Lewatit Monoplus SP112) has been studied in batch experiments under varying HNO3 concentrations (0.2–2.0 mol/dm3), La(III) and Ni(II) concentrations (25–200 mg/dm3), phase contact time (1–360 min), temperature (293–333 K), and resin mass (0.1–0.5 g). The experimental data revealed that the sorption process was dependent on all parameters used. The maximum sorption capacities were found at CHNO3 = 0.2 mol/dm3, m = 0.1 g, and T = 333 K. The kinetic data indicate that the sorption followed the pseudo-second order and film diffusion models. The sorption equilibrium time was reached at approximately 30 and 60 min for La(III) and Ni(II) ions, respectively. The equilibrium isotherm data were best fitted with the Langmuir model. The maximum monolayer capacities of Lewatit Monoplus SP112 were equal to 95.34 and 60.81 mg/g for La(III) and Ni(II) ions, respectively. The thermodynamic parameters showed that the sorption process was endothermic and spontaneous. Moreover, dynamic experiments were performed using the columns set. The resin regeneration was made using HCl and HNO3 solutions, and the desorption results exhibited effective regeneration. The ATR/FT-IR and XPS spectroscopy results indicated that the La(III) and Ni(II) ions were coordinated with the sulfonate groups.


2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaodong Li

Using straw and urea as raw materials, biochar (BC) and g-C3N4 were prepared by oxygen-free pyrolysis at 300°C and 550°C. BC/g-C3N4 was prepared by loading different amounts of g-C3N4 onto the surface of biochar and characterized by SEM and FT-IR. The adsorption effect on methylene blue (MB) was investigated from the aspects of dosage and pH. The studies of adsorption equilibrium isotherms and the kinetic and the thermodynamic parameters on the BC/g-C3N4 adsorbents are discussed. The results showed that BC/g-C3N4 0.16 g/L with a doping ratio of 1 : 3 was added to the MB solution with an initial concentration of 50 mg/L and pH=11. The adsorption rate and adsorption amount were 96.72% and 302.25 mg/g, respectively. The adsorption process included surface adsorption and intraparticle diffusion, which conformed to the pseudo-second-order kinetic model and Langmuir-Freundlich model. Thermodynamic parameters (ΔG0<0, ΔH0>0, and ΔS0>0) showed that the adsorption reaction is spontaneous, which positively correlated with temperature.


2021 ◽  
Vol 68 (2) ◽  
pp. 363-373
Author(s):  
Roya Salahshour ◽  
Mehdi Shanbedi ◽  
Hossein Esmaeili

In the present work, methylene blue was eliminated from aqueous solution using activated carbon prepared by lotus leaves. To perform the experiments, batch method was applied. Also, several analyses such as SEM, FTIR, EDAX and BET were done to determine the surface properties of the activated carbon. The results showed that the maximum sorption efficiency of 97.59% was obtained in initial dye concentration of 10 mg/L, pH of 9, adsorbent dosage of 4 g/L, temperature of 25 °C, contact time of 60 min and mixture speed of 400 rpm. Furthermore, the maximum adsorption capacity was determined 80 mg/g, which was a significant value. The experimental data was analyzed using pseudo-first order, pseudo-second order and intra-particle diffusion kinetic models, which the results showed that the pseudo-second order kinetic model could better describe the kinetic behavior of the sorption process. Also, the constant rate of the pseudo-second order kinetic model was obtained in the range of 0.0218–0.0345 g/mg.min. Moreover, the adsorption equilibrium was well described using Freundlich isotherm model. Furthermore, the thermodynamic studies indicated that the sorption process of methylene blue dye using the activated carbon was spontaneous and exothermic.


Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1734 ◽  
Author(s):  
Abel Adekanmi Adeyi ◽  
Siti Nurul Ain Md Jamil ◽  
Luqman Chuah Abdullah ◽  
Thomas Shean Yaw Choong ◽  
Kia Li Lau ◽  
...  

The paper evaluates the adsorptive potential of thiourea-modified poly(acrylonitrile-co-acrylic acid), (TA-poly(AN-co-AA)) for the uptake of cationic methylene blue (MB) from aquatic environments via a batch system. TA-poly(AN-co-AA) polymer was synthesized through redox polymerization and modified with thiourea (TA) where thioamide groups were introduced to the surface. Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), CHNS and Zetasizer were used to characterize the physico-chemical and morphological properties of prepared TA-poly(AN-co-AA). Afterwards, it was confirmed that incorporation of thioamide groups was successful. The adsorption kinetics and equilibrium adsorption data were best described, respectively, by a pseudo-second-order model and Freundlich model. Thermodynamic analysis showed the exothermic and spontaneous nature of MB uptake by TA-poly(AN-co-AA). The developed TA-poly(AN-co-AA) polymer demonstrated efficient separation of MB dye from the aqueous solution and maintained maximum adsorption capacity after five regeneration cycles. The findings of this study suggested that synthesized TA-poly(AN-co-AA) can be applied successfully to remove cationic dyes from aquatic environments.


2018 ◽  
Vol 78 (10) ◽  
pp. 2055-2063
Author(s):  
Asmaa Msaad ◽  
Mounir Belbahloul ◽  
Samir El Hajjaji ◽  
Abdeljalil Zouhri

Abstract In this work, the use of a novel low-cost adsorbent derived from Ziziphus lotus (ZL) and industrial carbon (IC) has been successfully applied to the removal of methylene blue (MB) from aqueous solutions. The efficiency of this material was studied through Lagergren pseudo-first-order and pseudo-second-order kinetic models. The process for the novel activated carbon and the IC were best represented by the pseudo-second-order rate model. Langmuir and Freundlich isotherms were used to describe the sorption equilibrium data. The Langmuir model turned out to be the most adequate and maximum capacities were measured to be 833.33 and 142.85 mg.g−1 for ZL activated carbon and IC from Sigma Aldrich, respectively. The thermodynamic study revealed that the sorption process is spontaneous and endothermic for the two adsorbents. To explain the effectiveness of MB removal, ZL activated carbon was characterized by scanning electron microscopy, Brunauer–Emmett–Teller surface area, X-ray diffraction and Fourier transform infrared spectroscopy.


2014 ◽  
Vol 881-883 ◽  
pp. 1175-1178
Author(s):  
Xu Man Wang ◽  
Cai Ning Zhang

By means of grafting polymerization, cross-linked starch-g-polyacrylamide (starch-g-PAM) was prepared and used to adsorb methylene blue (MB). Adsorption isotherm and kinetic of the sorption process were studied. The experimental results demonstrated that the prepared starch-g-PAM was an effective adsorbent for removal of MB from aqueous solution. The adsorption of MB by starch-g-PAM was Freundlich type, and the adsorption equation was caculated to be . Furthermore, the adsorption kinetics analysis demonstrated that the adsorption process followed the pseudo-second-order model.


2012 ◽  
Vol 178-181 ◽  
pp. 400-405
Author(s):  
Cai Ning Zhang ◽  
Xu Man Wang

By using grafting reaction, starch-g-poly (acrylic acid) (starch-g-PAA) hydrogel was prepared and used to adsorb methylene blue (MB). Adsorption isotherm and kinetic of the sorption process were studied. Meanwhile, various thermodynamic parameters were calculated. The absorption experimental results demonstrate that the prepared starch-g-PAA is an effective adsorbent for removal of MB from aqueous solution. The adsorption of MB by starch-g-PAA is Freundlich type. Furthermore, the adsorption kinetics analyze demonstrates that the adsorption process follows the pseudo-second-order model, and the adsorption is a multi-step process. Moreover, the calculated thermodynamic parameters indicate the spontaneous and endothermic nature of the adsorption process. The values of adsorption activation energy demonstrate that the adsorption is mainly diffusion-controlled process.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 842
Author(s):  
Cassiele T. Cesco ◽  
Artur J. M. Valente ◽  
Alexandre T. Paulino

Chitosan/DNA blend hydrogel (CDB) and chitosan/pectin blend hydrogel (CPB) were synthesized using an emulsion (oil-in-water) technique for the release of methylene blue (model molecule). Both hydrogels were characterized by swelling assays, Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM), before and after the methylene blue (MB) loading. Higher swelling degrees were determined for both hydrogels in simulated gastric fluid. FT-IR spectra inferred absorption peak changes and shifts after MB loading. The TGA results confirmed changes in the polymer network degradation. The SEM images indicated low porosities on the hydrogel surfaces, with deformed structure of the CPB. Smoother and more uniform surfaces were noticed on the CDB chain after MB loading. Higher MB adsorption capacities were determined at lower initial hydrogel masses and higher initial dye concentrations. The MB adsorption mechanisms on the hydrogel networks were described by the monolayer and multilayer formation. The MB release from hydrogels was studied in simulated gastric and intestinal fluids, at 25 °C and 37 °C, with each process taking place at roughly 6 h. Higher release rates were determined in simulated gastric fluid at 25 °C. The release kinetics of MB in chitosan/DNA and chitosan/pectin matrices follows a pseudo-second-order kinetic mechanism.


2020 ◽  
Vol 3 (1) ◽  
pp. 59
Author(s):  
Maria Melania Golor ◽  
Dessy Rosma ◽  
Shella Permatasari Santoso ◽  
Felycia Soetaredjo ◽  
Maria Yuliana ◽  
...  

In this work, citric acid (CIT) is proposed as a harmless alternative to epichlorohydrin (ECH) for crosslinking in the synthesis of cellulose hydrogels. Sugarcane bagasse was utilized as a source of cellulose fibers. Cellulose fibers were disintegrated using the solvent-dissolution method before forming a gel-like solution. Subsequently, CIT was added to initiate crosslinking, and the behavior was evaluated by adding various amounts of citric acid (0, 20, 30, and 40 wt%). Cellulose hydrogel with a good mechanical strength (10 mm penetration depth) was obtained from crosslinking using 40 wt% of CIT (HCIT-4), which is comparable to ECH-cross-linked hydrogel (HECH) that has a penetration depth of 8 mm. A proper amount of CIT molecules allows the crosslinking of the cellulose fibers into the hydrogel. The FT-IR analysis reveals a C-O-C band blue-shifting for HCIT-4 compared to HECH, with a gap difference of 82 cm-1. The crystallinity from XRD patterns of HCIT-4 is comparable to that of HECH, which confirms that CIT can be used as a substitute for ECH. The adsorption ability was evaluated against methylene blue dye, the isotherm and kinetic adsorption models for the adsorption system were determined. Freundlich and pseudo-second-order models correlate well to isotherm and kinetics data, suggests that the adsorbent possesses heterogeneous surface sites which adsorption controlled by chemisorption. The prepared HCIT-4 was able to remove 24.88 mg methylene blue/g of the hydrogel at 70 °C, meanwhile HECH only able to remove 12.01 mg/g. The adsorption capacity was increased when adsorption temperature increased, suggesting endothermic behavior.


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