scholarly journals Novel Cellulose Nanofibers/Polyvinyl Alcohol/Polyethyleneimine Nanoparticle for Cu2+ Removal in Water

2021 ◽  
Author(s):  
Rongrong Si ◽  
Chaojun Wu ◽  
Dongmei Yu ◽  
Qijun Ding ◽  
Ronggang Li
Keyword(s):  
Polyvinyl Alcohol ◽  
Freeze Drying ◽  
Removal Rate ◽  
Cellulose Nanofibers ◽  
Drying Method ◽  
Order Model ◽  
Bending Vibration ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Structurally Stable

Abstract In this study, environmentally friendly CNF/PVA/PEI nanoparticle was obtained by assembling PEI (polyethyleneimine) into CNF/PVA aerogels, which were prepared by freeze-drying method with the help of glutaraldehyde. FTIR results showed that PEI likely assembled into the CNF/PVA aerogel due to appearances of bending vibration of the CNF/PVA/PEI nanoparticle at 1615cm− 1. BET results further demonstrated that PEI have successfully assembled into aerogel since the specific surface area (22.93m2/g) of CNF/PVA/PEI nanoparticle was lower than that (56.37m2/g) of CNF/PVA aerogel. SEM results also showed that PEI could obviously regulate the morphology of CNF/PVA aerogel. TGA indicated that CNF/PVA/PEI nanoparticle was structurally stable at 216.4°C. The adsorption kinetics of the CNF/PVA/PEI nanoparticle for Cu2+ removal presented good correlations with the Pseudo-second-order model. The adsorption and desorption results showed that the removal rate of 2g/L CNF/PVA/PEI nanoparticle for Cu2+in water could reach more than 93% when the concentration of Cu2+ ranged from 20 to 80mg/L in one hour, and it could still retain more than 80% after 3 cycles.

Study on the Formaldehyde Adsorption Kinetics of Dry Waters

2014 ◽  
Vol 809-810 ◽  
pp. 907-911
Author(s):  
Jun Long Wang ◽  
Jie Hou ◽  
Ting Jiang ◽  
Yong Jun He ◽  
Yao Dong Liang
Keyword(s):  
Adsorption Kinetics ◽  
High Speed ◽  
Adsorption Process ◽  
Average Diameter ◽  
Adsorption Rate ◽  
Absorption Kinetics ◽  
Order Model ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Formaldehyde Adsorption

Dry waters with an average diameter of 82 μm were prepared by a high speed mixed route. The formaldehyde absorption kinetics of dry waters was investigated by simulating indoor formaldehyde pollution in glass chamber. The results showed that pseudo-second order model could be used to simulate the adsorption process; the adsorption rate was highest in the initial 60 minutes; when the adsorption lasted for 180 minutes, the adsorption reached equilibrium.

Adsorption Kinetics of Pb2+ Ions Using Chitosan Nanoparticles

2013 ◽  
Vol 367 ◽  
pp. 45-49
Author(s):  
Ying Hong ◽  
Ze Hui Zhong ◽  
You Shi Liu
Keyword(s):  
Adsorption Kinetics ◽  
Chitosan Nanoparticles ◽  
Second Order ◽  
Isotherm Model ◽  
Order Model ◽  
Adsorption Characteristics ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Second Order Model

Chitosan nanoparticles were prepared by crosslinkingusing TPP. SEM showed that chitosan nanoparticles were successfully obtained.The adsorption characteristics of chitosan nanoparticles were evaluated. Theresults demonstrated that chitosan nanoparticles were suitable for adsorbent toremoval Pb2+. The parameters for the adsorption of Pb2+by chitosan nanoparticles were also determined. It was shown that chitosannanoparticles were fit for Langmuir’s isotherm model and that the adsorptionkinetics of Pb2+ described by the pseudo-second-order model could bebest.

scholarly journals Enhanced removal of hexavalent chromium by different acid-modified biochar derived from corn straw: behavior and mechanism

2020 ◽  
Vol 81 (10) ◽  
pp. 2270-2280
Author(s):  
Yonggang Xu ◽  
Tianxia Bai ◽  
Yubo Yan ◽  
Yunfeng Zhao ◽  
Ling Yuan ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Hydrogen Ion ◽  
Corn Straw ◽  
Order Model ◽  
Freundlich Model ◽  
X Ray ◽  
Modified Biochar ◽  
Before And After ◽  
Pseudo Second Order ◽  
Kinetics Of

Abstract It is of great significance to remove Cr(VI) from water as a result of its high toxicity. Biochar from corn straw was modified by different acids (HNO3, H2SO4 and H3PO4) to remove Cr(VI) from aqueous solution. To estimate the removal mechanisms of Cr(VI) by the acid-modified biochars, batch experiments were performed in the light of contact time, Cr(VI) concentration, and pH, and the characteristics of acid-modified biochars before and after Cr(VI) adsorption were investigated by Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS). The adsorption kinetics of Cr(VI) by acid-modified biochars were consistent with the pseudo-second-order model, and the adsorption isotherm obeyed the Freundlich model. Furthermore, the acid- modified biochars could supply more oxygen-containing functional groups (-COOH and -OH) as electron donor (e−) and hydrogen ion (H+) to enhance the reduction of Cr(VI) to Cr(III), resulting in enhanced removal of Cr(VI). HNO3-modified biochar exhibited the highest removal efficiency of Cr(VI). In general, the acid modifition of biochar was an effective method to increase the removal of Cr(VI).

scholarly journals Kinetics of scandium recovery by TVEX-TBP from the solution formed after the salt chlorinator cake leaching

2020 ◽  
Vol 168 ◽  
pp. 00050
Author(s):  
Vadym Korovin ◽  
Yurii Pohorielov ◽  
Yurii Shestak ◽  
Oleksandr Valiaiev ◽  
Jose Luis Cortina
Keyword(s):  
Chemical Interaction ◽  
Extraction Process ◽  
Second Order ◽  
Order Kinetic ◽  
Order Model ◽  
Elovich Equation ◽  
Diffusion Phase ◽  
Leaching Solution ◽  
Pseudo Second Order ◽  
Kinetics Of

Kinetics of scandium recovery by TVEX containing tributyl phosphate was studied from the clarified leaching solution of salt chlorinator cake. To assess the contribution of each diffusion phase, experimental data were analyzed using a graphic method. To define the contribution of chemical interaction into the scandium extraction process, recovery kinetics was quantitatively described using pseudo-first order, pseudo-second order kinetic models and Elovich equation in linearized form. It was established that recovery kinetics was most accurately described with the pseudo-second-order model.

scholarly journals Anisotropic Cellulose Nanofibers/Polyvinyl Alcohol/Graphene Aerogels Fabricated by Directional Freeze-drying as Effective Oil Adsorbents

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 712 ◽  
Author(s):  
Lijie Zhou ◽  
Shengcheng Zhai ◽  
Yiming Chen ◽  
Zhaoyang Xu
Keyword(s):  
Polyvinyl Alcohol ◽  
Freeze Drying ◽  
High Efficiency ◽  
Cellulose Nanofibers ◽  
High Strength ◽  
Dip Coating ◽  
High Porosity ◽  
Water Contact ◽  
Water Separation ◽  
Composite Aerogel

Under the current situation of frequent oil spills, the development of green and recyclable high-efficiency oil-absorbing aerogel materials has attracted wide attention from researchers. In this study, we report a high-strength, three-dimensional hydrophobic cellulose nanofiber (CNF)/polyvinyl alcohol (PVA)/graphene oxide (GO) composite aerogel with an anisotropic porous structure, which was fabricated by directional freeze-drying technology using anisotropically grown ice crystals as a template, followed by hydrophobic treatment with a simple dip coating process. The prepared composite aerogel presented anisotropic multi-level pore microstructures, low density (17.95 mg/cm3) and high porosity (98.8%), good hydrophobicity (water contact angle of 142°) and great adsorption capacity (oil absorption reaching 96 times its own weight). More importantly, the oriented aerogel had high strength, whose compressive stress at 80% strain reached 0.22 MPa and could bear more than 22,123 times its own weight without deformation. Therefore, the CNF/PVA/GO composite aerogel prepared by a simple and easy-to-operate directional freeze-drying method is a promising absorbent for oil-water separation.

Study on Adsorption of U(VI) From Aqueous Solution by Activated MgO

2017 ◽  
Author(s):  
Qingqing Liu ◽  
Xiaoyan Li
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Adsorption Process ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Batch System ◽  
15Mg Dose ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Kinetics Of

The activated MgO was synthesized by microwave homo-precipitator method and characterized by SEM, EDS and FT-IR methods. It was used to adsorption of U(VI) from aqueous solution with batch system. The paper discussed the effect of pH, temperature, contact time, adsorbent dose and initial U(VI) concentration on the adsorption. The results showed that activated MgO has good adsorption capacity for U(VI), the removal rate and equilibrium adsorption capacity reached 83.5% and 84.04mg·g−1 at pH 5.0, 15mg dose and 313K,respectively. The adsorption kinetics of U(VI) onto activated MgO were better fitted with pseudo-second-order kinetic.The adsorption isotherm data were fitted well to Freundlich isotherm model.The thermodynamic parameters showed that the adsorption process is endothermic and spontaneous.

Adsorption Kinetics of Zn(II) from Aqueous Solutions onto Epichlorohydrin Crosslinked Chitosan

2012 ◽  
Vol 463-464 ◽  
pp. 7-11 ◽  
Author(s):  
Ming Yan Dang ◽  
Hong Min Guo ◽  
Yan Kun Tan
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Kinetics ◽  
Ph Value ◽  
Crosslinking Agent ◽  
Second Order ◽  
Order Model ◽  
Pseudo Second Order ◽  
Crosslinked Chitosan ◽  
Kinetics Of ◽  
Second Order Model

Chitosan was crosslinked using epichlorohydrin as crosslinking agent to prepare crosslinked chitosan which was used as an adsorbent for the removal of Zn(II) from aqueous solutions. The adsorption prosperities of Zn(II) on crosslinked chitosan were studied, including the influence of pH value and the adsorption kinetics. The kinetics of adsorption was discussed using two kinetic models, the pseudo first-order and the pseudo second-order model. Results reveal that the crosslinked chitosan is suitable as adsorbent to remove Zn(II) from dilute solution. The rate parameters for the Zn(II) by crosslinked chitosan were also determined. It was shown that the adsorption kinetics of Zn(II) could be best described by the pseudo second-order model and the adsorption process may involve a physical adsorption.

scholarly journals Kinetics of Adsorptive Removal of Drimarene Brilliant Red from Aqueous Solution Using Untreated Agricultural Residues

2016 ◽  
Vol 59 (1) ◽  
pp. 11-22
Author(s):  
Ch. Tahir Mehmood ◽  
Muhammad Arshad ◽  
Tayyab Ashfaq ◽  
Muhammad Bilal ◽  
Muhammad Shafiq ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Rice Husk ◽  
Analytical Data ◽  
Particle Sizes ◽  
Order Model ◽  
Orange Peels ◽  
Pseudo Second Order ◽  
Initial Adsorption ◽  
Kinetics Of ◽  
Solution Kinetics

The potential of untreated banana and orange peels, and rice husk was tested for drimarenebrilliant red (DBR) dye removal from aqueous solution. Kinetics was also studied in a batch experiment.Dose of adsorbents varied from 6 to 12 g/L, particle sizes 0.2 and 0.8 mm and contact time 2–32 h. Highdose and small particle size favoured DBR removal efficiency significantly. The highest adsorption capacitywas shown by rice husk (10 mg/g), then orange peels (9 mg/g) and the lowest by banana peels (4 mg/g).Langmuir isotherm (R2=0.99) and pseudo-second order model (R2=0.99) depicted well the equilibriumand best explained the kinetics for rice husk, respectively. Initial adsorption appeared as pore diffusionin all the cases and film diffusion was controlling the rate, later on. Based upon the analytical data, a simplemodel has been presented that fitted best to describe rice husk adsorption kinetics.

Study of Fluorescent Dyeing Process and Influence of Mixture Dyes on High-visibility

2015 ◽  
Vol 10 (1) ◽  
pp. 155892501501000
Author(s):  
Mohamed Hamdaoui ◽  
Ahlem Lanouar ◽  
Sabri Halaoua
Keyword(s):  
Fluorescent Dyes ◽  
Second Order ◽  
Disperse Dyes ◽  
Order Model ◽  
Nernst Equation ◽  
First Order ◽  
Dyeing Process ◽  
Pseudo Second Order ◽  
Polyester Dyeing ◽  
Kinetics Of

In this paper, we present the results of an investigation and analysis of an experimental study of fluorescent disperse dyes used for dyeing polyester fabrics to high-visibility colors. This paper describes the results of spectrophotometric color measurements for yellow luminous, red luminous and orange luminous fluorescent dyes and their matching with the requirements of the EN 471 standard. The results of this study showed that the adsorption isotherms of polyester dyeing with fluorescent disperse luminous dyes follow the Nernst equation; the Nernst constants were determined and interpreted. The adsorption kinetics of fluorescent disperse dyes on polyester is studied by using the peudo-first-order model, the pseudo-second-order equation and the intraparticle diffusion equation. The results show that pseudo-second-order models fit well the experimental data with higher average regression coefficients (R2 > 0.98). They also show that high-visibility is influenced by the dye concentration, and that the dye mixtures can affect the high-visibility.

Interaction Influence of Contact Time and pH on Cobalt Retention by Carbon Nanotubes Bearing Various Loads of TiO2 and Fe3O4

2021 ◽  
Vol 17 ◽  
Author(s):  
Ismail Fasfous ◽  
Amjad El-Sheikh ◽  
Anas Awad ◽  
Yahya El-Degs ◽  
Jamal Dawoud
Keyword(s):  
Carbon Nanotubes ◽  
Removal Rate ◽  
Cost Effective ◽  
Research Area ◽  
Second Order ◽  
Nano Materials ◽  
Solution Ph ◽  
Retention Capacity ◽  
Pseudo Second Order ◽  
Kinetics Of

Background: Nano-materials have facilitated remarkable advances in the remediation of many environmental problems. A few studies have tackled the removal of Co(II) from aqueous solutions using nano-materials. Herein, we recently studied the retention kinetics of cobalt species on carbon nanotubes (CNT) bearing different amounts of TiO2 and Fe3O4 nano-materials individually. c Method: CNT and their TiO2/Fe3O4-modified nano-material forms were well characterized. Cobalt retention by these adsorbents was investigated at different influencing factors: Co(II) content, solution pH, and time. The kinetic data were fitted with pseudo-first-order, pseudo-second-order rate models and intra-particle diffusion models for better elucidation of the mechanism of Co retention. Results: XRD evidenced the formation of TiO2 and Fe3O4. High loads of both oxides were needed for higher and faster Co retention by CNT. Co retention capacity increased with increasing the solution pH. The pseudo-second-order model presented the kinetics of Co retention at 30 oC, and 48% of available capacity was attained within the first hour of interaction by CNT-TiO2 and with a moderate S/L ratio of 0.5 g/L. Co retention was increased with the amount of oxide to reach a maximum value of 16. 40 mg/g (90.2% TiO2) and 13.60 mg/g (48.2% Fe3O4). The Jovanović equilibrium model predicted the maximum retention values as the nearest to the experimental ones. Conclusion: The potential of CNT-Fe3O4 /TiO2 nano-materials has been successfully demonstrated for the removal of cobalt, which makes them highly attractive and cost-effective adsorbents for wastewater treatment. The reported retention and removal rate values were relatively better than those seen in the literature. Loading different active oxides by CNT is an interesting research area as selective adsorbents can be fabricated with affordable experimental costs.

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