Use of nanoadvanced activated carbon, alumina and ferric adsorbents for humics removal from water: isotherm study

AbstractThe adsorption of humic substances on three different adsorbents was investigated and adsorption isotherms were applied in this research. The three adsorbents studied include granular activated carbon (GAC), ferric oxihydroxide in its beta form (β-FeOOH) and iron-coated activated alumina (AAFS). Physical and chemical characteristics of the adsorbents were also fully investigated. Calcium was added to the HS solution in order to represent water with a hardness equivalent to water hardness typically found in London (UK). The examination of the GAC indicated a large microporous area with lower surface area associated with meso- and macropores. The AAFS and β-FeOOH did not present any microporous area. The overall surface area was high for GAC (980 m2 g−1) but lower for AAFS (286 m2 g−1) and β-FeOOH (360 m2 g−1). The Freundlich isotherm model was fitted to all adsorbent–adsorbate systems. It was shown that GAC offered a large adsorption capacity for removal of low molecular weight humics F1 (MW 0–5 kDa) but not for substances with molecular weight larger than 10 kDa (F3). The β-FeOOH adsorption capacity was only 0.43 mg g−1, compared with 9.11 and 2.55 mg g−1 on GAC and AAFS, respectively. On the contrary, F1 is not well adsorbed and only F2 (5–10 kDa) can be efficiently removed by AAFS and β-FeOOH. It was strongly suggested that precipitation/condensation occurred on the adsorbent surface.

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Study of the Porous Structure and High Adsorption Capacity of Biomass-Based Activated Carbon Prepared from Aspen Wood by Ferric Nitrate III Activation

Journal of Biobased Materials and Bioenergy ◽

10.1166/jbmb.2021.2047 ◽

2021 ◽

Vol 15 (2) ◽

pp. 131-144

Author(s):

Chunjiang Jin ◽

Huimin Chen ◽

Luyuan Wang ◽

Xingxing Cheng ◽

Donghai An ◽

...

Keyword(s):

Activated Carbon ◽

Specific Surface ◽

Adsorption Capacity ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Mass Ratio ◽

Aspen Wood ◽

Surface Functional Groups ◽

Wood Sawdust

In this study, aspen wood sawdust was used as the raw material, and Fe(NO3)3 and CO2 were used as activators. Activated carbon powder (ACP) was produced by the one-step physicochemical activation method in an open vacuum tube furnace. The effects of different mass ratios of Fe(NO3)3 and aspen wood sawdust on the pore structure of ACP were examined under single-variable experimental conditions. The mass ratio was 0–0.4. The detailed characteristics of ACP were examined by nitrogen adsorption, scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The adsorption capacity of ACP was established by simulating volatile organic compounds (VOCs) using ethyl acetate. The results showed that ACP has a good nanostructure with a large pore volume, specific surface area, and surface functional groups. The pore volume and specific surface area of Fe-AC-0.3 were 0.26 cm3/g and 455.36 m2/g, respectively. The activator played an important role in the formation of the pore structure and morphology of ACP. When the mass ratio was 0–0.3, the porosity increased linearly, but when it was higher than 0.3, the porosity decreased. For example, the pore volume and specific surface area of Fe-AC-0.4 reached 0.24 cm3/g and 430.87 m2/g, respectively. ACP presented good VOC adsorption performance. The Fe-AC-0.3 sample, which contained the most micropore structures, presented the best adsorption capacity for ethyl acetate at 712.58 mg/g. Under the action of the specific reaction products nitrogen dioxide (NO2) and oxygen, the surface of modified ACP samples showed different rich C/O/N surface functional groups, including C-H, C=C, C=O, C-O-C, and C-N.

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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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STUDI ADSORPSI ZAT WARNA NAPHTHOL YELLOW S PADA LIMBAH CAIR MENGGUNAKAN KARBON AKTIF DARI AMPAS TEBU

Jurnal Kimia ◽

10.24843/jchem.2019.v13.i01.p16 ◽

2019 ◽

Vol 13 (1) ◽

pp. 104

Author(s):

W. P. Utoo1 ◽

E. Santoso ◽

G. Yuhaneka ◽

A. I. Triantini ◽

M. R. Fatqi ◽

...

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Surface Area ◽

Contact Time ◽

Adsorption Process ◽

Activation Process ◽

Adsorption Model ◽

High Adsorption ◽

Prolonged Contact ◽

Test Result

The aim of this research is to get activated carbon from sugarcane bagasse with high adsorption capacity to Naphthol Yellow S and to know factors influencing the adsorption capacity. Activated carbon is prepared by incomplete combustion of sugracane bagasse. The resulting carbon is activated with H2SO4 with concentration variation of 0.5; 1.0; 1.5 and 2.0 M and is continued by calcination at 400 °C. The measurement of the surface area of ??activated carbon by the methylene blue method indicates that the activation process successfully extends the surface area of carbon from 31.87 m2/g before activation to 66-72 m2/g after activation. Activated carbon with concentration of 2.0 M H2SO4 showed the highest surface area of ??71.85 m2/g, however, the best adsorption was shown by activated carbon with a concentration of 0.5 M H2SO4 with the adsorption capacity of 83.93%. The adsorption test showed that the best amount of adsorbent was 0.2 g with contact time for 30 minutes. Prolonged contact time can decrease the amount of Naphthol Yellow S adsorbed. The best adsorption test result was shown by sample with activator concentration of 0,5 M, mass of 0,2 g and contact time of 30 min with adsorption capacity 95,81% or amount of dye adsorbed equal to 143,72 mg/g. The adsorption study also showed that the entire Naphthol Yellow S adsorption process followed the Langmuir isothemal adsorption model. Qualitative testing of real batik waste indicates that activated carbon can reduce the dyes waste containing Naphthol Yellow Sexhibited by the color of batik waste which is more faded.

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Pinecone-Derived Activated Carbons as an Effective Medium for Hydrogen Storage

Energies ◽

10.3390/en13092237 ◽

2020 ◽

Vol 13 (9) ◽

pp. 2237

Author(s):

Sara Stelitano ◽

Giuseppe Conte ◽

Alfonso Policicchio ◽

Alfredo Aloise ◽

Giovanni Desiderio ◽

...

Keyword(s):

Activated Carbon ◽

Hydrogen Storage ◽

Adsorption Capacity ◽

Surface Area ◽

Hydrogen Adsorption ◽

Activated Carbons ◽

Chemical Activation ◽

Textural Properties ◽

Biomass Waste ◽

Wavelength Dispersive Spectrometry

Pinecones, a common biomass waste, has an interesting composition in terms of cellulose and lignine content that makes them excellent precursors in various activated carbon production processes. The synthesized, nanostructured, activated carbon materials show textural properties, a high specific surface area, and a large volume of micropores, which are all features that make them suitable for various applications ranging from the purification of water to energy storage. Amongst them, a very interesting application is hydrogen storage. For this purpose, activated carbon from pinecones were prepared using chemical activation with different KOH/precursor ratios, and their hydrogen adsorption capacity was evaluated at liquid nitrogen temperatures (77 K) at pressures of up to 80 bar using a Sievert’s type volumetric apparatus. Regarding the comprehensive characterization of the samples’ textural properties, the measurement of the surface area was carried out using the Brunauer–Emmett–Teller method, the chemical composition was investigated using wavelength-dispersive spectrometry, and the topography and long-range order was estimated using scanning electron microscopy and X-ray diffraction, respectively. The hydrogen adsorption properties of the activated carbon samples were measured and then fitted using the Langmuir/ Töth isotherm model to estimate the adsorption capacity at higher pressures. The results showed that chemical activation induced the formation of an optimal pore size distribution for hydrogen adsorption centered at about 0.5 nm and the proportion of micropore volume was higher than 50%, which resulted in an adsorption capacity of 5.5 wt% at 77 K and 80 bar; this was an increase of as much as 150% relative to the one predicted by the Chahine rule.

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Coupling ultrafiltration and adsorption onto activated carbon cloth: application to the treatment of highly coloured wastewaters

Water Science & Technology ◽

10.2166/wst.2000.0535 ◽

2000 ◽

Vol 42 (5-6) ◽

pp. 355-362 ◽

Cited By ~ 16

Author(s):

H. Pignon ◽

C. Brasquet ◽

P. Le Cloirec

Keyword(s):

Molecular Weight ◽

Activated Carbon ◽

Adsorption Capacity ◽

Membrane Filtration ◽

Flow Reactor ◽

Great Influence ◽

Dye Adsorption ◽

Operating Conditions ◽

Carbon Cloth ◽

Kinetics And Isotherms

The aim of this work is to evaluate the efficiency of Activated Carbon Cloths (ACCs) as a refining treatment of membrane filtration in the case of effluent streams containing both dyes and suspended solids (SS) or colloids responsible for turbidity. It is divided into two parts. First, dye adsorption experiments are carried out. Kinetics and isotherms enable us to show the feasibility of the adsorption and to study the influence of different operating conditions. The results demonstrate that adsorption is enhanced under acidic conditions, the adsorption capacity being increased by 40% in some cases. Moreover, microscopic characteristics of ACCs have a great influence on the adsorption process: there is a relationship between the adsorbent porosity and the adsorbate molecular weight, the mesoporous adsorbent being more efficious to remove the larger molecular weight dyes. In the case of low molecular weight compounds, the adsorbent with the higher specific surface area provides the greater adsorption capacity. Molecular connectivity indexes were used to confirm the correlation of the molecular structure of the adsorbates with their adsorbability. The second part consists of an estimation of the efficiency of the coupling of ultrafiltration and adsorption onto ACC. Tests performed on a laboratory-scale coupling show that a molecular weight cut-off of 3,000 D gives rise to a 98% removal of turbidity whereas dyes are not much retained. Furthermore, ultrafiltration is useful in improving the adsorption capacities of ACC in a continuous flow reactor (up to 50%).

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Adsorption of chromium (VI) from aqueous solutions on activated carbon

Water Science & Technology ◽

10.2166/wst.1994.0477 ◽

1994 ◽

Vol 30 (9) ◽

pp. 191-197 ◽

Cited By ~ 78

Author(s):

R. Leyva Ramos ◽

A. Juarez Martinez ◽

R. M. Guerrero Coronado

Keyword(s):

Activated Carbon ◽

Adsorption Isotherm ◽

Adsorption Capacity ◽

Ph Effect ◽

Freundlich Isotherm ◽

Maximum Adsorption Capacity ◽

Experimental Adsorption ◽

Ph Values ◽

Chromium Vi ◽

Adsorption Data

The adsorption isotherm of chromium (VI) on activated carbon was obtained in a batch adsorber. The experimental adsorption data were fitted reasonably well to the Freundlich isotherm. The effect of pH on the adsorption isotherm was investigated at pH values of 4, 6, 7, 8, 10 and 12. It was found that at pH < 6, Cr(VI) was adsorbed and reduced to Cr(III) by the catalytic action of the carbon and that at pH ≥ 12, Cr(VI) was not adsorbed on activated carbon. Maximum adsorption capacity was observed at pH 6 and the adsorption capacity was diminished about 17 times by increasing the pH from 6 to 10. The pH effect was attributed to the different complexes that Cr(VI) can form in aqueous solution. The adsorption isotherm was also affected by the temperature since the adsorption capacity was increased by raising the temperature from 25 to 40°C. It was concluded that Cr(VI) was adsorbed significantly on activated carbon at pH 6 and that the adsorption capacity was greatly dependent upon pH.

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Physicochemical Properties of Carbons Prepared from Physic Nut Waste by Phosphoric Acid and Potassium Hydroxide Activations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1719 ◽

2007 ◽

Vol 561-565 ◽

pp. 1719-1722 ◽

Cited By ~ 3

Author(s):

Chiravoot Pechyen ◽

Duangdao Aht-Ong ◽

Duangduen Atong ◽

Viboon Sricharoenchaikul

Keyword(s):

Activated Carbon ◽

Phosphoric Acid ◽

Physicochemical Properties ◽

Adsorption Capacity ◽

Surface Area ◽

Potassium Hydroxide ◽

Bet Surface Area ◽

Physic Nut ◽

Monolayer Adsorption ◽

Adsorption Data

Char derived from pyrolysis of physic nut waste at 400-800°C was used for the preparation of activated carbon by chemical impregnation of phosphoric acid and potassium hydroxide. The original char exhibited the BET surface area in the range of 120-250 m2·g-1. The surface area increased to 480 and 532 m2·g-1 when activated with H3PO4 and KOH, respectively. Equilibrium adsorption data was found to be best represented by the Langmuir isotherm with maximum monolayer adsorption capacity of 560.13 mg·g-1 at 30°C. The adsorption capacity of the physic nut residue activated carbon was comparable to commercial activated carbon.

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Solution blowing of activated carbon nanofibers for phenol adsorption

RSC Advances ◽

10.1039/c4ra10897c ◽

2015 ◽

Vol 5 (8) ◽

pp. 5801-5808 ◽

Cited By ~ 23

Author(s):

Xiaoxiao Tao ◽

Guoqing Zhou ◽

Xupin Zhuang ◽

Bowen Cheng ◽

Xiaojie Li ◽

...

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Surface Area ◽

Carbon Nanofibers ◽

Phenol Adsorption ◽

Solution Blowing ◽

Activated Carbon Nanofibers ◽

Special Surface

Activated carbon nanofibers fabricated through solution blowing and activation possessed a high special surface area and excellent adsorption capacity.

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Comparison on the Characteristics of Bio-Based Porous Carbons by Physical and Novel Chemical Activation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.554.22 ◽

2014 ◽

Vol 554 ◽

pp. 22-26 ◽

Cited By ~ 3

Author(s):

Jibril Mohammed ◽

Noor Shawal Nasri ◽

Muhammad Abbas Ahmad Zaini ◽

Usman Hamza Dadum ◽

Murtala Musa Ahmed

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Chemical Activation ◽

Value Added ◽

Potassium Acetate ◽

Lower Surface ◽

Physical Activation ◽

Porous Carbons ◽

Surface Areas ◽

Agricultural Materials

There is significantly abundant portion of waste agricultural materials in the world serving as environmental challenge, however, they could be converted into useful value added products like activated carbon. Coconut shell based carbons were synthesized using physical activation by CO2 and chemical activation with potassium hydroxide and potassium acetate. The BET surface areas and pore volumes are 361m2/g and 0.19cm3/g for physical activation, 1353m2/g and 0.61cm3/g for activation with KOH and 622m2/g and 0.31cm3/g for potassium acetate activated carbon. From the Fourier Transform Infrared Spectroscopy analysis, hydroxyls, alkenes and carbonyl functional groups were identified with more prominence on the chemically activated porous carbons. Thermogravimetric analysis (TGA) results showed occurrence of moisture pyrolysis at 105°C, the pyrolysis of hemicellulose and cellulose occurred at 160–390°C and lignin at (390-650°C). Carbonization at 700°C and 2hrs had highest yield of 32%. Physical activation yielded lower surface area with approximately 88% micropores. On the other hand, chemically activation yielded higher surface area with elevated mesopores. The porous carbons can be applied to salvage pollution challenges.

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Adsorption of cadmium(II) from aqueous solution onto activated carbon

Water Science & Technology ◽

10.2166/wst.1997.0278 ◽

1997 ◽

Vol 35 (7) ◽

pp. 205-211 ◽

Cited By ~ 51

Author(s):

R. Leyva-Ramos ◽

J. R. Rangel-Mendez ◽

J. Mendoza-Barron ◽

L. Fuentes-Rubio ◽

R. M. Guerrero-Coronado

Keyword(s):

Activated Carbon ◽

Adsorption Isotherm ◽

Adsorption Capacity ◽

Freundlich Isotherm ◽

Carbon Surface ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Ph Values ◽

Average Percent Deviation ◽

Initial Ph

The adsorption isotherm of cadmium on activated carbon was measured in a batch adsorber. Effects of temperature and solution pH on the adsorption isotherm were investigated by determining the adsorption isotherm at temperatures of 10, 25, and 40°C and at initial pH values from 2 to 8. Langmuir isotherm better fitted the experimental data since the average percent deviation was lower than with the Freundlich isotherm It was noticed that the amount of Cd2+ adsorbed was reduced about 3 times by increasing the temperature from 10 to 40°C. It was found that Cd2+ was not adsorbed on activated carbon at pH of 2 or lower and that Cd2+ was precipitated out as Cd(OH)2 at pH values above 9. Maximum adsorption capacity was observed at pH of 8 and the adsorption capacity was decreased about 12 times by reducing the initial pH from 8 to 3. According to the cadmium speciation diagram the predominant species below pH of 8 is Cd2+. Thus, cadmium was adsorbed on the activated carbon surface as Cd2+. It was concluded that the adsorption capacity is a strong function of pH and temperature.

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