Sequestration of Pb(II) Ions from Aqueous Systems with Novel Green Bacterial Cellulose Graphene Oxide Composite

In this study, a novel green adsorbent material prepared by the esterification of bacterial cellulose (BC) and graphene oxide (GO), richly containing hydroxyl, alkyl, and carboxylate groups was characterised by FTIR (Fourier Transform infrared spectroscopy), XRD (X-ray diffraction), SEM (Scanning electron microscopy) and TGA (Thermo-graphimetric analysis). The specific surface area (SSA) and pore size distribution (PSD) analysis of materials were also analysed. Batch experiments–adsorption studies confirmed the material to have a very high Pb2+ removal efficiency of over 90% at pH 6–8. Kinetic studies showed that the uptake of metal ions was rapid with equilibrium attained after 30 min and fitted well with the pseudo-second-order rate model (PSO). Isotherm results with a maximum adsorption capacity (Qmax) of 303.03 mg/g were well described by Langmuir’s model compared to Freundlich. Desorption and re-adsorption experiments realised that both adsorbent and adsorbates could be over 90–95% efficiently recovered and reused using 0.1 M HNO3 and 0.1 M HCl.

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Efficient adsorption of chlorpyrifos onto modified activated carbon by gamma irradiation; a plausible adsorption mechanism

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2020-1765 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Mohamed S. Yahia ◽

Ahmed S. Elzaref ◽

Magdy B. Awad ◽

Ahmed M. Tony ◽

Ahmed S. Elfeky

Keyword(s):

Gamma Irradiation ◽

Area Measurement ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

X Ray ◽

First Order ◽

Pseudo Second Order ◽

Ft Ir ◽

Pseudo First Order ◽

Kinetics Of

Abstract Commercial Granulated Active Carbon (GAC) has been modified using 10 Gy dose Gamma irradiation (GAC10 Gy) for increasing its ability of air purification. Both, the raw and treated samples were applied for removing Chlorpyrifos pesticide (CPF) from ambient midair. Physicochemical properties of the two materials were characterized by Fourier Transform Infrared (FT-IR) and Raman spectroscopy. The phase formation and microstructure were monitored using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), supported with Energy-Dispersive X-ray (EDX). The Surface area measurement was detected using BET particle size prosometry. Obtained outcomes showed that, the maximum adsorption capacity, given by Langmuir equations, was greatly increased from 172.712 to 272.480 mg/g for GAC and GAC10 Gy, respectively, with high selectivity. The overall removal efficiency of GAC10 Gy was notably comparable to that of the original GAC-sorbent. The present study indicated that, gamma irradiation could be a promising technique for treating GAC and turned it more active in eliminating the pesticides pollutants from surrounding air. The data of equilibrium has been analyzed by Langmuir and Freundlich models, that were considerably better suited for the investigated materials than other models. The process kinetics of CPF adsorbed onto both tested carbon versions were found to obey the pseudo first order at all concentrations with an exception at 70 mg/l using GAC, where, the spontaneous exothermic adsorption of Chlorpyrifos is a strong function for the pseudo-first order (PFO) and pseudo second order (PSO) kinetics.

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Water polishing of phenol by walnut green hull as adsorbent: an insight of adsorption isotherm and kinetic

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2016.068 ◽

2016 ◽

Vol 6 (4) ◽

pp. 544-552 ◽

Cited By ~ 16

Author(s):

H. Godini ◽

F. Hashemi ◽

L. Mansuri ◽

M. Sardar ◽

Ghasem Hassani ◽

...

Keyword(s):

Langmuir Isotherm ◽

Surface Characteristics ◽

Xrd Analysis ◽

Isotherm Models ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

X Ray ◽

Maximum Sorption ◽

Pseudo Second Order ◽

Xrd Techniques

The present paper aims to investigate water purification of phenol by walnut green hull adsorbent. The surface characteristics of the adsorbent were studied using Fourier transform infra-red (FTIR), scanning electron microscope, and X-ray diffraction (XRD) techniques. The presence of functional groups such as hydroxyl and carbonyl onto walnut green hull surface was proved by FTIR analysis. Also quartz, cellulose and hematite were detected in the XRD analysis of samples by an X-ray diffractometer. The maximum sorption was achieved at pH 4.0. Data were evaluated for compliance with the Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. The results indicate that the data for adsorption of phenol onto walnut green hull fitted well with the Langmuir isotherm. The maximum adsorption capacity of the adsorbent was achieved by Langmuir isotherm 17.8 mg g–1. Also, the adsorption kinetics of phenol on the adsorbent were studied. The rates of sorption were found to conform to pseudo-second-order kinetics with good correlation.

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Removal of Cesium and Strontium From Radioactive Wastewater by Prussian Blue Nanorods

10.21203/rs.3.rs-1200891/v1 ◽

2022 ◽

Author(s):

Chuqing Yao ◽

Yaodong Dai ◽

Shuquan Chang ◽

Haiqian Zhang

Keyword(s):

Prussian Blue ◽

Photoelectron Spectroscopy ◽

Adsorption Process ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

X Ray ◽

Radioactive Wastewater ◽

Pseudo Second Order ◽

Co Precipitation ◽

Solvothermal Methods

Abstract In this work, novel Prussian blue tetragonal nanorods were prepared by template-free solvothermal methods for removal of radionuclide Cs and Sr. It was worth that Prussian blue nanorods exhibited the better adsorption performance than co-precipitation PB or Prussian blue analogue composites. Thermodynamic analysis implied that adsorption process was spontaneous and endothermic which was described well with Langmuir isotherm and pseudo-second-order equation, the maximum adsorption capacity of PB nanorod was estimated to be 194.26 mg g-1 and 256.62 mg g-1 for Cs+ and Sr2+. The adsorption mechanism of Cs+ and Sr2+ was studied by X-ray photoelectron spectroscopy, X-ray diffraction and 57Fe Mössbaure spectroscopy, the results revealed that Cs+ entered in PB crystal to generate a new phase, the most of Sr2+ was trapped in internal crystal and the other exchanged Fe2+. Furthermore, the effect of co-existing ions and pH for PB adsorption process were also investigated. The results suggest that PB nanorods were outstanding candidate for removal of Cs+ and Sr2+ from radioactive wastewater.

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Kinetic Adsorption of Direct Yellow Onto Zn/Al and Zn/Fe Layered Double Hydroxides

Science & Technology Indonesia ◽

10.26554/sti.2019.4.4.101-104 ◽

2019 ◽

Vol 4 (4) ◽

pp. 101

Author(s):

Neza Rahayu Palapa ◽

Bakri Rio Rahayu ◽

Tarmizi Taher ◽

Aldes Lesbani ◽

Risfidian Mohadi

Keyword(s):

Layered Double Hydroxides ◽

Kinetic Studies ◽

X Ray Diffraction ◽

X Ray ◽

First Order ◽

Bet Method ◽

Pseudo Second Order ◽

Time Variations ◽

Co Precipitation ◽

Double Hydroxides

Zn/Al and Zn/Fe layered double hydroxides has successfully synthesized by co-precipitation methods with molar ration 3:1. The samples were characterized using X-Ray Diffraction, Fourier Transform Infrared Spectroscopy and Surface Area using BET method. In this study, Zn/Al and Zn/Fe layered double hydroxides were used to remove direct yellow dye in aqueous solution. The experiments were carried out time variations with the aim of observing the kinetic studies. The results showed that the adsorption of direct yellow onto Zn/Al and Zn/Fe layered double hydroxides based on co-efficient correlation kinetic models more fit using pseudo-second-order than pseudo-first-order.

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Adsorption isotherm, kinetic and mechanism studies of 2-nitrophenol on sedimentary phosphate

Mediterranean Journal of Chemistry ◽

10.13171/mjc.4.6/0151123/sebti ◽

2015 ◽

Vol 4 (6) ◽

pp. 289-296 ◽

Cited By ~ 6

Author(s):

Hind Yaacoubi ◽

Zuo Songlin ◽

Mustapha Mouflih ◽

Mina Gourai ◽

Said Sebti

Keyword(s):

Kinetic Studies ◽

Intraparticle Diffusion ◽

X Ray Diffraction ◽

Equilibrium Isotherms ◽

X Ray ◽

First Order ◽

Adsorption Data ◽

Pseudo Second Order ◽

Pseudo First Order ◽

Equilibrium Adsorption Capacity

Sedimentary phosphate (SP) was used as an adsorbent for the removal of 2-nitrophenol from aqueous solutions in an attempt to investigate (the feasibility of) its application (to) in wastewater purification.Â The adsorbent was characterized by X-ray diffraction (XRD), IR spectroscopy, Fluorescence X and BET.Â The results indicated that the SP (was) is francolite (Ca10 (PO4,CO3)6F2) and mesoporous. The effect of the adsorption time and the pH of the solution were studied. The pseudo-first-order, pseudo-second-order and intraparticle diffusion models were used to fit adsorption data in the kinetic studies. The equilibrium isotherms were determined using the Langmuir, Freundlich and Dubinin-Radushkevich models. The results show that the Dubinin-Radushkevich isotherm had better agreement with the 2-nitrophenol adsorption on SP with a correlation coefficient of 0.98, an equilibrium adsorption capacity of 633 mg. g-1 and a corresponding contact time of 2 h. The results imply that intraparticle diffusion could be summarized as the basic rate-controlling mechanisms during 2-nitrophenol adsorption on SP.

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Superflexibility of graphene oxide

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1605121113 ◽

2016 ◽

Vol 113 (40) ◽

pp. 11088-11093 ◽

Cited By ~ 51

Author(s):

Philippe Poulin ◽

Rouhollah Jalili ◽

Wilfrid Neri ◽

Frédéric Nallet ◽

Thibaut Divoux ◽

...

Keyword(s):

Graphene Oxide ◽

Unique Feature ◽

Bending Rigidity ◽

X Ray Diffraction ◽

Synchrotron Source ◽

X Ray ◽

Bending Modulus ◽

Bendable Electronics ◽

Very High

Graphene oxide (GO), the main precursor of graphene-based materials made by solution processing, is known to be very stiff. Indeed, it has a Young’s modulus comparable to steel, on the order of 300 GPa. Despite its very high stiffness, we show here that GO is superflexible. We quantitatively measure the GO bending rigidity by characterizing the flattening of thermal undulations in response to shear forces in solution. Characterizations are performed by the combination of synchrotron X-ray diffraction at small angles and in situ rheology (rheo-SAXS) experiments using the high X-ray flux of a synchrotron source. The bending modulus is found to be 1kT, which is about two orders of magnitude lower than the bending rigidity of neat graphene. This superflexibility compares with the fluidity of self-assembled liquid bilayers. This behavior is discussed by considering the mechanisms at play in bending and stretching deformations of atomic monolayers. The superflexibility of GO is a unique feature to develop bendable electronics after reduction, films, coatings, and fibers. This unique combination of properties of GO allows for flexibility in processing and fabrication coupled with a robustness in the fabricated structure.

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ADSORPTION OF URANIUM FROM AQUEOUS SOLUTION BY Cu0.5Ni0.5Fe2O4 – REDUCED GRAPHENE OXIDE NANOCOMPOSITES

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/54/5a/12056 ◽

2018 ◽

Vol 54 (5A) ◽

pp. 9

Author(s):

Tran Quang Dat

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Ph Effect ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

X Ray ◽

Reduced Graphene ◽

20 Nm ◽

Oxide Composites ◽

Efficient Adsorbent

Cu0.5Ni0.5Fe2O4 – reduced graphene oxide composites (CNF-rGO) as an efficient adsorbent for the adsorption of uranium (VI) have been synthesized by a two-steps methods. The structures and the physicochemical properties of adsorbents are characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy (RAMAN) and Vibrating sample magnetometer (VSM) measurement. It was found that rGO were exfoliated and decorated homogeneously with CNF nanoparticles having diameters of 20 nm. The saturated magnetization (Ms) value was estimated to be 60 emu/g, remanences (Mr) and coercive forces (Hc) near to zero, indicating that obtained material is superparamagnetic. The pH effect, contact time and adsorption isotherms were examined in batch experiments. The adsorption isotherm agreed well with the Langmuir model, having a maximum adsorption capacity of 256 mg/g, at pH = 6, T = 298 K.

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Adsorptive Removal of Drimarene Brilliant Blue by Thermo Stable, Eco-friendly Graphene Oxide Reinforced Polyvinyl Alcohols Hydrogels With High Reusability Potential

10.21203/rs.3.rs-937274/v1 ◽

2021 ◽

Author(s):

Adeel Mustafa ◽

Nazia Yaqoob ◽

Maheen Almas ◽

Shagufta Kamal ◽

Khalid Mahmood Zia ◽

...

Keyword(s):

Graphene Oxide ◽

Adsorption Capacity ◽

Thermo Gravimetric Analysis ◽

Freundlich Isotherm ◽

Brilliant Blue ◽

Isotherm Models ◽

Maximum Adsorption Capacity ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Pseudo Second Order

Abstract In this study graphene oxide (GO) reinforced polyvinyl alcohol (PVA) composites hydrogels were synthesized and used as efficient adsorbents for Drimarene Brilliant Blue K-4BL. GO nanoparticles (NPs) were synthesized by modified Hummer’s method. The composites were characterized by Fourier transform infrared spectroscopy (FT-IR), Thermo-gravimetric analysis (TGA), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed homogeneous dispersion of reinforcement in the synthesized composites. Moreover thermal stability of the composites was significantly enhanced by the addition of graphene oxide nanoparticles. The synthesized composites were used for the removal of Drimarene brilliant Blue from model waste water. The effect of pH, content of GONPs and initial concentration of Drimarene Brilliant Blue K-4BL on the adsorption capacity of synthesized GO/PVA composites were investigated. The equilibrium isothermal data were studied by applying Langmuir and Freundlich isotherm models. Results demonstrated that the adsorption process is well described by the Langmuir adsorption isotherm. According to the Langmuir model, maximum adsorption capacity i.e. 32mg/g was obtained at 0.7% GO/PVA composite. From the kinetic study it was concluded that pseudo-second-order model is the best fitted. Synthesized composites showed excellent reusability (almost 95 %) for the adsorption of Drimarene Brilliant Blue K-4BL after four successive cycles of adsorption and desorption. Thus, the GO/PVA composites demonstrated a great potential in terms of cost effectiveness, efficiency and reusability for the removal of Drimarene Brilliant Blue K-4BL dye.

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Equilibrium and kinetics studies of Direct blue 71 adsorption from aqueous solutions using modified zeolite

Adsorption Science & Technology ◽

10.1177/0263617416684836 ◽

2017 ◽

Vol 36 (1-2) ◽

pp. 80-94 ◽

Cited By ~ 5

Author(s):

Nezam Mirzaei ◽

Amir Hossein Mahvi ◽

Hooshyar Hossini

Keyword(s):

Low Cost ◽

Second Order ◽

Maximum Adsorption Capacity ◽

X Ray Diffraction ◽

Modified Zeolite ◽

X Ray ◽

Direct Blue ◽

Equilibrium And Kinetics ◽

Pseudo Second Order ◽

Direct Blue 71

This study deals with the application of Iranian zeolite as a low cost adsorbent for the removal of the Direct blue 71 (DB 71) from colored solution. Important parameters including equilibrium and contact time, initial dye concentration, effect of pH, and zeolite dosage were evaluated. Maximum dye removal was obtained at about 99.8% for 25 mg/L at 120 min of equilibrium. Higher adsorption efficiency of direct dye was obtained at higher dose and acidic pH. To analyze the adsorption equilibrium and kinetic, Langmuir, Freundlich, and Temkin isotherms as well as four kinetic models encompassing pseudo first-order, pseudo second-order, intraparticle diffusion, and Elovich were evaluated. The Langmuir isotherm ( R2 = 0.995) and pseudo second-order models, gave the best fit to equilibrium experimental data. In Langmuir analysis, the maximum adsorption capacity (qm) by 13.66 mg/g was determined. Finally, the characteristics of zeolite including both natural and modified, such as compositions, surface morphology by X-ray diffraction technique (XRD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM) were obtained. According to XRF analysis, it was demonstrated that Al2O3 and SiO2 are the most part of natural and modified zeolite. Furthermore, the clinoptilolite was determined as the significant crystalloid phase by XRD pattern.

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Pembuatan Ca-Mg-Al Hydrotalcite-like compound dari Brine Water untuk menjerap Cr(VI)

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.15.1.27032.124-137 ◽

2019 ◽

Vol 15 (1) ◽

pp. 124

Author(s):

Eddy Heraldy ◽

Edi Pramono ◽

Yohana Gita Aprilliaa

Keyword(s):

Fourier Transform ◽

Surface Area ◽

Second Order ◽

Maximum Adsorption Capacity ◽

Optimum Conditions ◽

X Ray Diffraction ◽

X Ray ◽

A Value ◽

Infra Red ◽

Pseudo Second Order

Pembuatan Ca-Mg-Al hydrotalcite-like compound (HTlc) dengan metode kopresipitasi telah dilakukan. Hydrotalcite-like yang terbentuk dikarakterisasi dengan X-ray Diffraction (XRD), Fourier Transform Infra Red (FTIR), Surface Area Analyzer (SAA) dan digunakan sebagai adsorben Cr(VI). Hasil karakterisasi XRD menunjukkan adanya nilai d 7,54 Å pada sudut 2 theta 11,73º yang merupakan ciri hydrotalcite dengan interlayer karbonat. Hasil ini diperkuat dengan adanya gugus hidroksi pada daerah bilangan gelombang IR sekitar 3441 cm-1 serta gugus karbonat pada 1361 cm-1. Proses adsorpsi Cr(VI) dengan menggunakan Ca-Mg-Al hydrotalcite-like menunjukkan kondisi optimum pada pH 3 dan waktu kontak 20 menit. Kinetika adsoprsi Cr(VI) oleh Ca-Mg-Al hydrotalcite-like cenderung mengikuti persamaan kinetika pseudo second order dan isoterm adsorpsinya mengikuti model isoterm Langmuir. Kapasitas adsorpsi maksimum Cr(VI) menggunakan Ca-Mg-Al hydrotalcite-like lebih besar dibandingkan menggunakan hydrotalcite komersial. Pita spektra FTIR setelah adsorpsi Cr(VI) menunjukkan ion kromium terserap ke dalam Ca-Mg-Al hydrotalcite-like compound.Synthesis of Ca-Mg-Al Hydrotalcite-like compound from Brine Water for Cr(VI) removal. The synthesis of Ca-Mg-Al hydrotalcite-like compound (Htlc) with a coprecipitation method had been done. Hydrotalcite-like product was characterized by X-ray diffraction (XRD), Fourier transform infra red (FTIR), surface area analyzer (SAA) and was used as an adsorbent of Cr(VI). The XRD characterization result indicates a value of d 7.54 Å at 2 theta 11.73º, which is a characteristic of hydrotalcite with carbonate interlayer. These results are confirmed by the presence of a hydroxy group at wavenumber of IR around 3441 cm-1 and carbonate groups in the 1361 cm-1. The adsorption of Cr(VI) using the Ca-Mg-Al hydrotalcite-like showed the optimum conditions at pH 3 and 20 minutes contact time. The adsorption kinetic of Cr(VI) by Ca-Mg-Al hydrotalcite-like tends to follow the pseudo second order equation and the adsorption isotherm tends to follow the Langmuir model. The maximum adsorption capacity of Cr(VI) using the Ca-Mg-Al hydrotalcite-like is greater than that of using commercial hydrotalcite. Morever, the FTIR spectra analyzed after Cr(VI) adsorption indicates that chromium ion was adsorbed into of Ca-Mg-Al hydrotalcite-like compound.

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