Removal of erythrosine dye in aqueous solution using chitosan beads and chitosan-tripolyphosphate beads

Chitosan (CHS) and chitosan-tripolyphosphate beads (CTTP) were used for the removal of Erythrosine dye in batch adsorption experiments. The initial pH, agitation period, and adsorbent dosage were studied to determine the influence of these parameters on the adsorption capacity of the beads. Based on the initial pH study, the adsorption capacity for both adsorbents were found to be at pH 6. As the initial pH was increased, the adsorption capacity reduced for both beads. Based on the agitation period study, the kinetics of the adsorption process was determined. It was found that both CHS and CTPP followed the pseudo-second-order kinetic model with the highest adsorption capacity were attained at 50 and 60 minutes, respectively. An additional parameter on the adsorbent dosage was studied for CTTP beads to further improve on the removal capacity. The optimum adsorbent dosage for CHS and CTTP was achieved at 0.05 g and 0.6 g, respectively. An isotherm study was carried out on Erythrosine dye at the concentration of 20 mg/L – 100 mg/L for CHS and 20 mg/L – 150 mg/L for CTPP. It was found that the experimental data for CHS fitted the monolayer Langmuir model. Meanwhile, CTPP favored the multilayer Freundlich model. The CTPP was found to be effective in adsorbing a high concentration of dye, whereby the percentage of removal obtained was 92.6 % at the initial concentration of 150 mg/L of Erythrosine. Meanwhile, for CHS, the percentage of removal attained was 90.0% at the initial concentration of 60 mg/L of Erythrosine.

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Adsorption of cadmium by biochar produced from pyrolysis of corn stalk in aqueous solution

Water Science & Technology ◽

10.2166/wst.2016.319 ◽

2016 ◽

Vol 74 (6) ◽

pp. 1335-1345 ◽

Cited By ~ 12

Author(s):

Fengfeng Ma ◽

Baowei Zhao ◽

Jingru Diao

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Ionic Strength ◽

Ph Value ◽

Batch Adsorption ◽

Order Kinetic ◽

Corn Stalk ◽

Adsorbent Dosage ◽

Initial Ph ◽

Adsorbent Particle

The purpose of this work is to investigate adsorption characteristic of corn stalk (CS) biochar for removal of cadmium ions (Cd2+) from aqueous solution. Batch adsorption experiments were carried out to evaluate the effects of pH value of solution, adsorbent particle size, adsorbent dosage, and ionic strength of solution on the adsorption of Cd2+ onto biochar that was pyrolytically produced from CS at 300 °C. The results showed that the initial pH value of solution played an important role in adsorption. The adsorptive amount of Cd2+ onto the biochar decreased with increasing the adsorbent dosage, adsorbent particle size, and ionic strength, while it increased with increasing the initial pH value of solution and temperature. Cd2+ was removed efficiently and quickly from aqueous solutions by the biochar with a maximum capacity of 33.94 mg/g. The adsorption process was well described by the pseudo-second-order kinetic model with the correlation coefficients greater than 0.986. The adsorption isotherm could be well fitted by the Langmuir model. The thermodynamic studies showed that the adsorption of Cd2+ onto the biochar was a spontaneous and exothermic process. The results indicate that CS biochar can be considered as an efficient adsorbent.

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Sheet-like Skeleton Carbon Derived from Shaddock Peels with Hierarchically Porous Structures for Ultra-Fast Removal of Methylene Blue

Water ◽

10.3390/w13182554 ◽

2021 ◽

Vol 13 (18) ◽

pp. 2554

Author(s):

Panlong Dong ◽

Hailin Liu ◽

Shengrui Xu ◽

Changpo Chen ◽

Suling Feng ◽

...

Keyword(s):

Methylene Blue ◽

Adsorption Capacity ◽

Surface Area ◽

Adsorption Process ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Initial Concentration ◽

Hierarchically Porous ◽

Column Adsorption

To remove the pollutant methylene blue (MB) from water, a sheet-like skeleton carbon derived from shaddock peels (SPACs) was prepared by NaOH activation followed by a calcination procedure under nitrogen protection in this study. Characterization results demonstrated that the as-prepared SPACs displayed a hierarchically porous structure assembled with a thin sheet-like carbon layer, and the surface area of SPAC-8 (activated by 8 g NaOH) was up to 782.2 m2/g. The as-prepared carbon material presented an ultra-fast and efficient adsorption capacity towards MB due to its macro-mesoporous structure, high surface area, and abundant functional groups. SPAC-8 showed ultrafast and efficient removal capacity for MB dye. Adsorption equilibrium was reached within 1 min with a removal efficiency of 99.6% at an initial concentration of 100 mg/g under batch adsorption model conditions. The maximum adsorption capacity for MB was up to 432.5 mg/g. A pseudo-second-order kinetic model and a Langmuir isotherm model described the adsorption process well, which suggested that adsorption rate depended on chemisorption and the adsorption process was controlled by a monolayer adsorption, respectively. Furthermore, column adsorption experiments showed that 96.58% of MB was removed after passing through a SPAC-8 packed column with a flow rate of 20 mL/min, initial concentration of 50 mg/L, and adsorbent dosage of 5 mg. The as-prepared adsorbent displays potential value in practical applications for dye removal due to its ultrafast and efficient adsorption capacity.

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Benzene Removal by Iron Oxide Nanoparticles Decorated Carbon Nanotubes

Journal of Nanomaterials ◽

10.1155/2016/5654129 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 14

Author(s):

Aamir Abbas ◽

Basim Ahmed Abussaud ◽

Ihsanullah ◽

Nadhir A. H. Al-Baghli ◽

Marwan Khraisheh ◽

...

Keyword(s):

Carbon Nanotubes ◽

Iron Oxide ◽

Iron Oxide Nanoparticles ◽

Contact Time ◽

Batch Adsorption ◽

Oxide Nanoparticles ◽

Order Kinetic ◽

Initial Concentration ◽

Adsorbent Dosage ◽

Benzene Removal

In this paper, carbon nanotubes (CNTs) impregnated with iron oxide nanoparticles were employed for the removal of benzene from water. The adsorbents were characterized using scanning electron microscope, X-ray diffraction, BET surface area, and thermogravimetric analysis. Batch adsorption experiments were carried out to study the adsorptive removal of benzene and the effect of parameters such as pH, contact time, and adsorbent dosage. The maximum removal of benzene was 61% with iron oxide impregnated CNTs at an adsorbent dosage 100 mg, shaking speed 200 rpm, contact time 2 hours, initial concentration 1 ppm, and pH 6. However, raw CNTs showed only 53% removal under same experimental conditions. Pseudo-first-order kinetic model was found well to describe the obtained data on benzene removal from water. Initial concentration was varied from 1 to 200 mg/L for isotherms study. Langmuir isotherm model was observed to best describe the adsorption data. The maximum adsorption capacities were 987.58 mg/g and 517.27 mg/g for iron oxide impregnated CNTs and raw CNTs, respectively. Experimental results revealed that impregnation with iron oxide nanoparticles significantly increased the removal efficiency of CNTs.

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Performance Evaluation of Small Sized Powdered Ferric Hydroxide as Arsenic Adsorbent

Water ◽

10.3390/w10070957 ◽

2018 ◽

Vol 10 (7) ◽

pp. 957 ◽

Cited By ~ 11

Author(s):

Muhammad Usman ◽

Ioannis Katsoyiannis ◽

Manassis Mitrakas ◽

Anastasios Zouboulis ◽

Mathias Ernst

Keyword(s):

Adsorption Capacity ◽

Tap Water ◽

Ferric Hydroxide ◽

Equilibrium Concentration ◽

Arsenic Species ◽

Batch Adsorption ◽

Order Kinetic ◽

Isothermal Adsorption ◽

Water Matrix ◽

The Impact

The small sized powdered ferric oxy-hydroxide, termed Dust Ferric Hydroxide (DFH), was applied in batch adsorption experiments to remove arsenic species from water. The DFH was characterized in terms of zero point charge, zeta potential, surface charge density, particle size and moisture content. Batch adsorption isotherm experiments indicated that the Freundlich model described the isothermal adsorption behavior of arsenic species notably well. The results indicated that the adsorption capacity of DFH in deionized ultrapure water, applying a residual equilibrium concentration of 10 µg/L at the equilibrium pH value of 7.9 ± 0.1, with a contact time of 96 h (i.e., Q10), was 6.9 and 3.5 µg/mg for As(V) and As(III), respectively, whereas the measured adsorption capacity of the conventionally used Granular Ferric Hydroxide (GFH), under similar conditions, was found to be 2.1 and 1.4 µg/mg for As(V) and As(III), respectively. Furthermore, the adsorption of arsenic species onto DFH in a Hamburg tap water matrix, as well as in an NSF challenge water matrix, was found to be significantly lower. The lowest recorded adsorption capacity at the same equilibrium concentration was 3.2 µg As(V)/mg and 1.1 µg As(III)/mg for the NSF water. Batch adsorption kinetics experiments were also conducted to study the impact of a water matrix on the behavior of removal kinetics for As(V) and As(III) species by DFH, and the respective data were best fitted to the second order kinetic model. The outcomes of this study confirm that the small sized iron oxide-based material, being a by-product of the production process of GFH adsorbent, has significant potential to be used for the adsorptive removal of arsenic species from water, especially when this material can be combined with the subsequent application of low-pressure membrane filtration/separation in a hybrid water treatment process.

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Possibility of Removing Phosphates from Activated Charbon Made from Date Kernels

Engineering and Technology Journal ◽

10.47191/etj/v6i3.03 ◽

2021 ◽

Vol 06 (03) ◽

Author(s):

Nora Seghairi ◽

Keyword(s):

Activated Carbon ◽

Natural Waters ◽

Activated Carbons ◽

Kinetic Studies ◽

Phosphate Adsorption ◽

Initial Concentration ◽

Adsorbent Dosage ◽

Isotherm Study ◽

Freundlich Isotherms ◽

Batch Tests

Phosphates in natural waters and whatever their origin, promote the formation of algae, reduce dissolved oxygen and reduce biodiversity in aquatic ecosystems. At high doses, phosphate salts can cause health problems. The objective of our study was to develop a simple, efficient and environmentally friendly sorption depollution technique on available and inexpensive media. We have studied the adsorption of phosphate on activated carbons prepared from date kernels. Batch tests were carried out in order to study different operating parameters such as the effect of contact time, pH, initial phosphate concentration and adsorbent dosage and adsorption kinetic. The sorption equilibrium was analyzed by Langmuir, Freundlich isotherms model. Results show that the phosphate adsorption was reversible and the quantity adsorbed reached its maximum value (14.49 mg/g) after 40 minutes. It was also found that phosphate uptake was affected by variation of pH, initial concentration of phosphate and activated carbon dosage. The adsorption improved with an acidic pH (pH = 6), initial concentration and adsorbent dosage. The results of kinetic studies revealed that adsorption phosphate on activated carbon based on date kernels (Biocar) and the intra-particle diffusion involved in the adsorption mechanism. Also, isotherm study showed that Langmuir isotherm best fit the data and the adsorption was a physical type.

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Nanoparticle Fe3O4 magnetized activated carbon from Armeniaca sibirica shell for the adsorption of Hg(II) ions

BioResources ◽

10.15376/biores.16.3.6100-6120 ◽

2021 ◽

Vol 16 (3) ◽

pp. 6100-6120

Author(s):

Yinan Hao ◽

Yanfei Pan ◽

Qingwei Du ◽

Xudong Li ◽

Ximing Wang

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Ph Value ◽

Removal Rate ◽

Freundlich Isotherm ◽

Entropy Change ◽

Isotherm Models ◽

Order Kinetic ◽

Adsorption Parameters ◽

Initial Concentration

Armeniaca sibirica shell activated carbon (ASSAC) magnetized by nanoparticle Fe3O4 prepared from Armeniaca sibirica shell was investigated to determine its adsorption for Hg2+ from wastewater. Fe3O4/ASSAC was characterized using XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and BET (Brunauer–Emmett–Teller). Optimum adsorption parameters were determined based on the initial concentration of Hg2+, reaction time, reaction temperature, and pH value in adsorption studies. The experiment results demonstrated that the specific surface area of ASSAC decreased after magnetization; however the adsorption capacity and removal rate of Hg2+ increased 0.656 mg/g and 0.630%, respectively. When the initial concentration of Hg2+ solution was 250 mg/L and the pH value was 2, the adsorption time was 180 min and the temperature was 30 °C, and with the Fe3O4/ASSAC at 0.05 g, the adsorption reaching 97.1 mg/g, and the removal efficiency was 99.6%. The adsorption capacity of Fe3O4/ASSAC to Hg2+ was in accord with Freundlich isotherm models, and a pseudo-second-order kinetic equation was used to fit the adsorption best. The Gibbs free energy ΔGo < 0，enthalpy change ΔHo < 0, and entropy change ΔSo < 0 which manifested the adsorption was a spontaneous and exothermic process.

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Removal of Cu(II) from Aqueous Solutions Using Amine-Doped Polyacrylonitrile Fibers

Applied Sciences ◽

10.3390/app10051738 ◽

2020 ◽

Vol 10 (5) ◽

pp. 1738

Author(s):

Kay Thwe Aung ◽

Seung-Hee Hong ◽

Seong-Jik Park ◽

Chang-Gu Lee

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Isotherm Models ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Equilibrium Studies ◽

Naoh Solution ◽

Surface Modified ◽

Pan Fibers

Polyacrylonitrile (PAN) fibers were prepared via electrospinning and were modified with diethylenetriamine (DETA) to fabricate surface-modified PAN fibers. The surface-modified PAN fibers were used to evaluate their adsorption capacity for the removal of Cu(II) from aqueous solutions. Batch adsorption experiments were performed to examine the effects of the modification process, initial concentration, initial pH, and adsorbent dose on the adsorption of Cu(II). Kinetic analysis revealed that the experimental data fitted the pseudo-second-order kinetic model better than the pseudo-first-order model. Adsorption equilibrium studies were conducted using the Freundlich and Langmuir isotherm models, and the findings indicated that the PAN fibers modified with 85% DETA presented the highest adsorption capacity for Cu(II) of all analyzed samples. Moreover, the results revealed that the Freundlich model was more appropriate than the Langmuir one for describing the adsorption of Cu(II) onto the modified fibers at various initial Cu(II) concentrations. The maximum adsorption capacity was determined to be 87.77 mg/g at pH 4, and the percent removal of Cu(II) increased as the amount of adsorbent increased. Furthermore, the surface-modified PAN fibers could be easily regenerated using NaOH solution. Therefore, surface-modified PAN fibers could be used as adsorbents for the removal of Cu(II) from aqueous solutions.

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Removal of Chromium(VI) by Chitosan Beads Modified with Sodium Dodecyl Sulfate (SDS)

Applied Sciences ◽

10.3390/app10144745 ◽

2020 ◽

Vol 10 (14) ◽

pp. 4745

Author(s):

Xiaoyu Du ◽

Chihiro Kishima ◽

Haixin Zhang ◽

Naoto Miyamoto ◽

Naoki Kano

Keyword(s):

Sodium Dodecyl Sulfate ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Sodium Dodecyl ◽

Isotherm Models ◽

Order Kinetic ◽

Chitosan Beads ◽

X Ray ◽

Chromium Vi ◽

Dodecyl Sulfate

In this study, chitosan beads modified with sodium dodecyl sulfate (SDS) were successfully synthesized and employed for the removal of chromium(VI) (Cr(VI)). The adsorption performance of the adsorbent (SDS-chitosan beads) was examined by batch experiments. The partition coefficient (PC) as well as the adsorption capacity were evaluated to assess the true performance of the adsorbent in this work. The adsorbent (SDS-chitosan beads) showed a maximum Cr(VI) adsorption capacity of 3.23 mg·g−1 and PC of 9.5 mg·g−1·mM−1 for Cr(VI). The prepared adsorbent was characterized by different techniques such as scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS) and Fourier transform-infrared spectroscopy (FT-IR). We used inductively coupled plasma mass spectrometry (ICP-MS) for the determination of Cr(VI) in solution. The experimental data could be well-fitted by pseudo-second-order kinetic and Langmuir isotherm models. The thermodynamic studies indicated that the adsorption process was favorable under the higher temperature condition. The SDS-modified chitosan beads synthesized in this work represent a promising adsorbent for removing Cr(VI).

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Biosorption of hexavalent chromium from aqueous solution by polyethyleneimine-modified ultrasonic-assisted acid hydrochar from Sargassum horneri

Water Science & Technology ◽

10.2166/wst.2020.167 ◽

2020 ◽

Vol 81 (6) ◽

pp. 1114-1129 ◽

Cited By ~ 1

Author(s):

Jun Wang ◽

Qinglong Xie ◽

Ao Li ◽

Xuejun Liu ◽

Fengwen Yu ◽

...

Keyword(s):

Aqueous Solution ◽

Photoelectron Spectroscopy ◽

Batch Adsorption ◽

Crosslinking Reaction ◽

Order Kinetic ◽

Adsorption Capacities ◽

Initial Ph ◽

Ultrasonic Assisted ◽

Order Kinetic Model ◽

Pseudo Second Order

Abstract In this study, an efficient route to synthesizing polyethyleneimine-modified ultrasonic-assisted acid hydrochar (PEI-USAH) is developed and reported. Ultrasonic irradiation technique was used as surface modification method to shorten the crosslinking reaction for hydrochar and polyethyleneimine (PEI). The PEI-USAH showed an excellent adsorption capacity for Cr(VI) from aqueous solution. The physicochemical properties of this PEI-modified adsorbent were comparatively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis and CNHS analysis. The effects of contact time, initial pH, and biosorbent dose on adsorption capacities were investigated. The batch adsorption experiments showed that PEI-USAH possessed the maximum adsorption capacities of 94.38 mg/g and 330.84 mg/g for initial Cr(VI) concentration of 100 mg/L and 500 mg/L, respectively. Furthermore, this adsorption process could be fitted to Langmuir adsorption and described by the pseudo second order kinetic model. Based on the above findings, PEI-USAH could be used as a potential adsorbent for removal of Cr(VI) from wastewater.

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Batch and continuous fixed bed adsorption of heavy metals removal using activated charcoal from neem (Azadirachta indica) leaf powder

Scientific Reports ◽

10.1038/s41598-020-72583-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Himanshu Patel

Keyword(s):

Heavy Metals ◽

Flow Rate ◽

Activated Charcoal ◽

Batch Adsorption ◽

Order Kinetic ◽

Column Study ◽

Initial Concentration ◽

Bed Height ◽

Leaf Powder ◽

Batch Treatment

Abstract The present investigate was intended for adsorption of heavy metals i.e. Pb, Cu, Cr, Zn, Ni and Cd onto activated charcoal prepared from neem leaf powder (AC-NLP) using batch and column studies. Batch adsorption was performed using different variables like adsorbent dose, temperature and contact duration. Thermodynamic analysis of batch treatment concluded that adsorption is thermodynamically feasible and endothermic. This adsorption followed the Pseudo second-order kinetic model derived from correlation coefficient values of chemical kinetic studies. For column study, interpretation of breakthrough curves and parameters were conducted by varying flow rate, initial concentration and bed height; and reveal that optimum conditions were lower flow rate (5 mL/min) and lower initial concentration (5 mg/L) and higher bed height (20 cm). Comparisons of batch and column study through isotherm models were evaluated and column study is more preferred than batch treatment. Maximum Thomas adsorption capacity was achieved upto 205.6, 185.8, 154.5, 133.3, 120.6, 110.9 mg/g for Pb, Cu, Cd, Zn, Ni and Cr respectively. This removal pattern is elucidated by metal ionic properties. Various adsorbing agents such as acids and bases were utilized for adsorption–desorption of AC-NLP.

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