Impact of adsorbent carbons and carbon surface conductivity on adsorption capacity of CO2, CH4, N2 and gas separation

The main and new surface modification methods of activated carbon (AC) and their influence on application (adsorption capacity) were reviewed. Adsorption capacity is an important issue, contributing to hazardous substances environment management. According to literature, it is true that surface chemistry strongly affects adsorption capacity. Surface chemistry can be modified by several methods that lead to different activated carbon properties. Furthermore, adsorbate properties, and their relationships with surface structure, can impact adsorption properties. Surface modifications can be conducted by adding some atoms to the surface structure, making the surface more acidic or basic. Introduction of oxygen and ammonia atoms (chemical modification) are the main processes to make the surface more acidic and basic, respectively, although may bring chemical wastes to environment. Surface modification is done by chemical and physical modifications that lead activated carbons to present different properties. The main and new methods of chemical and physical modifications are compared and presented in this paper. Some new physical methods, like corona treatment, plasma discharge and microwave radiation, can be applied to cause surface modifications. Corona treatment can be a practical and new way to cause surface modification on an activated carbon surface.

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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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ADSORPSI ZAT WARNA METILEN BIRU DENGAN KARBON AKTIF DARI KULIT DURIAN MENGGUNAKAN KOH DAN NaOH SEBAGAI AKTIVATOR

Jurnal Teknik Kimia USU ◽

10.32734/jtk.v6i1.1565 ◽

2017 ◽

Vol 6 (1) ◽

pp. 49-55 ◽

Cited By ~ 1

Author(s):

Farida Hanum ◽

Rikardo Jgst Gultom ◽

Maradona Simanjuntak

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Surface Area ◽

Contact Time ◽

Wavelength Region ◽

Second Order ◽

Carbon Surface ◽

Maximum Adsorption Capacity ◽

Activation Process ◽

Maximum Surface

Durian is a kind of tropical fruits which can grow well in Indonesia. Durian is containing 60-75% shell. Durian shell could be a potential alternative to activated carbon because it contains 57.42% carbon. The aim of this research is to know the effect of contact time and stirring speed to activated carbon adsorption capacity from durian shell with KOH and NaOH as activators. FTIR (Fourier Transform Infra Red) analysis showed the activation process effects on absorption intensity wavelength region and resulted in formation of C = C aromatic tape, so that the nature of the charcoal becomes more polar compared with the initial condition. Analysis using spectrophotometer UV-Vis to determine absorbance and final concentration of each variation of contact time and stirring speed. The results showed that the maximum adsorption capacity obtained by activation of KOH and NaOH on stirring speed of 150 rpm and a contact time of 90 minutes is equal to 3.92 mg / g and 3.8 mg / g respectively. The maximum surface area obtained by activation of KOH and NaOH during the stirring speed 130 rpm and a contact time of 120 minutes is equal to 1785.263 m2 / g and 1730.332 m2 / g respectively. The maximum surface area obtained from this research has met the standards of commercial activated carbon surface area was between 800-1800 m2/ g. Modeling pseudo second order presents a more representative adsorption data, a second order equation is based on the assumption that adsorption step is chemosorption.

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Breaking the trade-off between selectivity and adsorption capacity for gas separation

Chem ◽

10.1016/j.chempr.2021.07.007 ◽

2021 ◽

Author(s):

Naveen Kumar ◽

Soumya Mukherjee ◽

Nathan C. Harvey-Reid ◽

Andrey A. Bezrukov ◽

Kui Tan ◽

...

Keyword(s):

Adsorption Capacity ◽

Gas Separation ◽

Trade Off

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Effect of Different Treatment on the Adsorption of p-Cresol by Activated Carbon

Eurasian Chemico-Technological Journal ◽

10.18321/ectj590 ◽

2017 ◽

Vol 5 (1) ◽

pp. 55 ◽

Cited By ~ 1

Author(s):

Sirous Nouri

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Activated Carbons ◽

Molecular Form ◽

Carbon Surface ◽

Ionic Form ◽

Freundlich Model ◽

London Dispersion ◽

Carbon Change ◽

London Dispersion Forces

Adsorption of p-Cresol by three activated carbons (one untreated and two treated) was carried out at 301 K and at controlled pH conditions. By treating the activated carbon the PZC and adsorption capacity (Qmax) of carbon change. The adsorption capacity of each carbon, by using the homogenous Langmuir-Freundlich model, was found to comparing the effect of different treatment. At pH lower than pKa of p-cresol (molecular form), it was observed that the electron density of aromatic ring and also those of the carbon surface, are the main forces involved in the adsorption process, by affecting the extent of London dispersion forces. Treating by H2 increase the PZC and treating by H2SO4 decrease this factor. At higher pH (in ionic form), it was found that the electrostatic forces played a significant role on the extent of adsorption. In this condition the adsorption of the solute dependent on the concentration of anionic form of the solute. The effect of pH must be considered from its combined effects on the carbon surface and on the solute molecules. It was found that the uptake of the molecular form of the aromatic solute was dependent on the PZC of the carbon.

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Activated Carbon/Transition Metal (Ni, In, Cu) Hexacyanoferrate Nanocomposites for Cesium Adsorption

Materials ◽

10.3390/ma12081253 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1253 ◽

Cited By ~ 9

Author(s):

Julien Kiener ◽

Lionel Limousy ◽

Mejdi Jeguirim ◽

Jean-Marc Le Meins ◽

Samar Hajjar-Garreau ◽

...

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Activated Carbon ◽

Transition Metal ◽

Adsorption Capacity ◽

Carbon Surface ◽

Carbon Oxidation ◽

Copper Hexacyanoferrate ◽

Metal Type ◽

Metal Hexacyanoferrate

Transition metal hexacyanoferrate/microporous activated carbon composites were obtained using a simple successive impregnation approach. The effect of metal type (nickel, indium, or copper), and the carbon oxidation on the composite characteristics (porosity, metal structure, and particle size), as well as on the removal efficiency of cesium from aqueous solution was investigated. Successful formation of the desired metal hexacyanoferrate phase was achieved and the size of the metallic nanoparticles and their dispersion in the carbon network was found to depend on the metal type, with the indium and nickel-based materials exhibiting the smallest particle size distribution (< 10 nm). Adsorption tests performed under batch conditions demonstrate that the copper hexacyanoferrate/activated carbon composite present the highest cesium removal capacity from aqueous solution (74.7 mg·g−1) among the three studied metal-based nanocomposites. The carbon oxidation treatment leads to the increase in the number of functional groups to the detriment of the porosity but allows for an improvement in the Cs adsorption capacity. This indicates that the Cs adsorption process is governed by the carbon surface chemistry and not its porosity. Moreover, combining oxidized carbon support with copper hexacyanoferrate induces the highest cesium adsorption capacity (101.5 mg·g−1). This could be related to synergistic effects through two absorption mechanisms, i.e., a cation exchange mechanism of Cs with the metallic hexacyanoferrate phase and Cs adsorption via carbon oxygen surface groups, as demonstrated using X-ray photoelectron spectroscopy (XPS) analyses.

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Synergy Effect of Nitrogen and Molybdenum on Activated Carbon Matrix for Selective Adsorptive Desulfurization: Insights into Surface Chemistry Modification

10.21203/rs.3.rs-322025/v1 ◽

2021 ◽

Author(s):

Musa O Azeez ◽

Abdulkadir Tanimu ◽

Khalid Alhooshani ◽

Saheed A. Ganiyu

Keyword(s):

Activated Carbon ◽

Surface Chemistry ◽

Adsorption Capacity ◽

Surface Area ◽

Photoelectron Spectroscopy ◽

Pore Volume ◽

Carbon Surface ◽

Synergy Effect ◽

Adsorptive Desulfurization ◽

X Ray

Abstract This study reports the synthesis of mesoporous metal-modified nitrogen doped activated carbon (AC-N-Mo) from date seeds by ZnCl2 activation and its applicability for selective adsorptive desulfurization of dibenzothiophene (DBT). The AC-N-Mo exhibits higher adsorption capacity for DBT at 100 mg-S/L with the maximum value of 99.7% corresponding to 19.94 mg-S/g at room temperature than the unmodified carbon with 17.96 mg-S/g despite its highest surface area and pore volume of 1027 m2g− 1 and 0.55 cm3g− 1 respectively. The adsorption capacity breakthrough follows the order AC-N-Mo > AC-Mo > AC > AC-N. AC-N-Mo also displayed excellent selectivity in the presence of aromatics (toluene, naphthalene and 1-methylisoquinoline). The enhancement in the DBT uptake capacities of AC-N-Mo is attributed to synergy effect of nitrogen heteroatom that aid well dispersion of molybdenum nanoparticles on carbon surface thereby improving its surface chemistry and promising textural characteristics. The kinetic studies showed that the DBT adsorption proceeds via pseudo-second order kinetics while the isotherm revealed that both Freundlich and Langmuir fit the data but Freundlich fit the data more accurately for the best performing adsorbent. The physico-chemical properties (surface area, pore volume, carbon content, particle size etc.) of as-prepared adsorbents namely; AC, AC-N, AC-N-Mo and AC-Mo were characterized by N2- physisorption, X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Spectroscopy/Energy Dispersive Spectroscopy (SEM/EDS), Raman Spectroscopy (RS), Fourier Transform Infrared Spectroscopy (FTIR) and Ammonia-Temperature-Programmed Desorption (NH3-TPD).

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Synthesis of Iron Oxide Nanoparticle Functionalized Activated Carbon and Its Applications in Arsenic Adsorption

Journal of Analytical Methods in Chemistry ◽

10.1155/2021/6668490 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Hoang Thu Ha ◽

Pham Tuan Phong ◽

Tran Dinh Minh

Keyword(s):

Activated Carbon ◽

Iron Oxide ◽

Specific Surface ◽

Adsorption Capacity ◽

Surface Area ◽

Specific Surface Area ◽

Carbon Surface ◽

Iron Oxide Nanoparticle ◽

Batch Adsorption ◽

Contaminated Water

This work reveals the As(V) adsorption behaviors onto iron oxide (Fe3O4) nanoparticles modified activated carbon (AC), originally developed from biochar (BC), as a green adsorbent denoted by FAC. Since FAC has abundant surface functional groups and a desired porous structure that is favorable for the removal of As(V) in contaminated water, FAC has greatly enhanced the As(V) adsorption capacity of the original BC. Various methods were employed to characterize the FAC characteristics and adsorption mechanism, including pHpzc determination, BET specific surface area, elemental analysis (EA), and scanning electron microscopy (SEM). Results show that the AC surface was successfully modified by iron oxide nanoparticles, enhancing the porosity and specific surface area of original adsorbent. Batch adsorption tests indicated a well-fitted Langmuir model and pseudo-second-order model for As(V) adsorption. Additionally, the highest adsorption capacity (Qmax = 32.57 mg/g) by FAC was higher than previously reported literature reviews. Until now, no article was conducted to research the effect of carbon surface chemistry and texture on As removal from waters. It is required to obtain a rational view of optimal conditions to remove As from contaminated water.

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Preparation of Activated Carbon from Bagasse by Microwave-Assisted Phosphoric Acid Activation

Walailak Journal of Science and Technology (WJST) ◽

10.48048/wjst.2021.22796 ◽

2021 ◽

Vol 18 (16) ◽

Author(s):

Suthatip SINYOUNG ◽

Weerawut CHAIWAT ◽

Kittipong KUNCHARIYAKUN

Keyword(s):

Activated Carbon ◽

Phosphoric Acid ◽

Adsorption Capacity ◽

Microwave Energy ◽

Carbon Surface ◽

Acid Activation ◽

Fixed Carbon ◽

Microwave Assisted ◽

Phosphoric Acid Activation ◽

Iodine Adsorption

This research focuses on the utilization of bagasse as activated carbon (AC) under microwave-assisted phosphoric acid activation. The AC was activated using various frequencies of microwave energy combined with phosphoric acid before the carbonization process. Results indicated that the AC obtained from bagasse under microwave-assisted phosphoric acid had improved properties, i.e. fixed carbon, surface area, and iodine adsorption capacity. However, the loss of AC properties could be attributed to microwave energy exceeding a limit of 800 W. The optimum activated condition in this research was the use of microwave energy 500 W assisted phosphoric acid, which had fixed carbon, surface area, and iodine adsorption capacity at 88.34 ± 0.67 %, 781 m2/g, and 852 ± 6.0 mg/g, respectively. HIGHLIGHTS Microwave energy and phosphoric acid is applied to pretreat bagasse Bagasse pretreatment by microwave-assisted H3PO4 enhances the properties of AC Optimum condition is pretreatment by phosphoric acid and microwave energy at 500 W GRAPHICAL ABSTRACT

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