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

2000 ◽  
Vol 42 (5-6) ◽  
pp. 355-362 ◽  
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%).

scholarly journals Various Impregnation Methods Used for the Surface Modification of the Adsorbent: A Review

2018 ◽  
Vol 7 (4.7) ◽  
pp. 330 ◽  
Author(s):  
C. R. Girish ◽  
. .
Keyword(s):  
Surface Modification ◽  
Activated Carbon ◽  
Adsorption Capacity ◽  
Surface Properties ◽  
Chemical Treatment ◽  
Water Contamination ◽  
Recent Time ◽  
Operating Conditions ◽  
Physical Chemical

The water contamination is an important crisis which is to be addressed in the recent time. The pollutants present in wastewater are treated by adsorption using activated carbon, which is considered as one of the effective method. The adsorbent has to be modified to improve the adsorption capacity and the surface properties. Various methods such as physical, chemical treatment, impregnation and functionalization techniques are available. Impregnation is one of the effective method carried out for surface modification and to increase the adsorption capacity. Therefore, current study investigates the different impregnation methods used for the surface modification of the adsorbent. It also reviews the various precursors used for adsorbent preparation, the impregnating agent, the operating conditions and the adsorption capacity of the adsorbent.  

scholarly journals Modeling and Optimization for Production of Rice Husk Activated Carbon and Adsorption of Phenol

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Y. S. Mohammad ◽  
E. M. Shaibu-Imodagbe ◽  
S. B. Igboro ◽  
A. Giwa ◽  
C. A. Okuofu
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Removal Efficiency ◽  
Rice Husk ◽  
Adsorption Process ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Process Variables ◽  
Adsorbent Dosage ◽  
Pretreatment Temperature

Modeling of adsorption process establishes mathematical relationship between the interacting process variables and process optimization is important in determining the values of factors for which the response is at maximum. In this paper, response surface methodology was employed for the modeling and optimization of adsorption of phenol onto rice husk activated carbon. Among the action variables considered are activated carbon pretreatment temperature, adsorbent dosage, and initial concentration of phenol, while the response variables are removal efficiency and adsorption capacity. Regression analysis was used to analyze the models developed. The outcome of this research showed that 99.79% and 99.81% of the variations in removal efficiency and adsorption capacity, respectively, are attributed to the three process variables considered, that is, pretreatment temperature, adsorbent dosage, and initial phenol concentration. Therefore, the models can be used to predict the interaction of the process variables. Optimization tests showed that the optimum operating conditions for the adsorption process occurred at initial solute concentration of 40.61 mg/L, pretreatment temperature of 441.46°C, adsorbent dosage 4 g, adsorption capacity of 0.9595 mg/g, and removal efficiency of 97.16%. These optimum operating conditions were experimentally validated.

Adsorption Characteristics of Uranyl Ions on Carboxymethylated Polyethyleneimine (CM-PEI) / Activated Carbon Composites

2007 ◽  
Vol 124-126 ◽  
pp. 1257-1260 ◽  
Author(s):  
Ke Chon Choi ◽  
Yongju Jung ◽  
Seok Kim ◽  
Soo Jin Park ◽  
Hyung Ik Lee ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Great Influence ◽  
Isotherm Models ◽  
Carbon Composites ◽  
Uranyl Ions ◽  
Adsorption Characteristics ◽  
Adsorption Data ◽  
Langmuir Isotherm Model ◽  
Adsorption Phenomena

We present the adsorption characteristics of uranyl ions on a new and innovative composite which was composed of a carboxymethylated polyethyleneimine (CM-PEI) and an activated carbon (F400) with a nanopore less than 2 nm in diameter. In this study, we examined the adsorption phenomena of uranyl ions on the CM-PEI/F400 composite and evaluated the adsorption data using various isotherm models. It was found that the adsorption of uranyl ions on the CM-PEI/F400 composite obeys the Langmuir isotherm model. In addition, it was observed that pH of solutions had great influence on the adsorption capacity of uranyl ions on the CM-PEI/F400 composite. Specially, the adsorption capacity of uranyl ions was linearly increased with an increase of pH at pH > 3.0.

scholarly journals Effect of Changes in Physical Properties of Granular Activated Carbon (GAC) on the Adsorption of Natural Organic Matter (NOM) with Increasing the Number of Thermal Regeneration: Pore Size and NOM Molecular Weight

2021 ◽  
Vol 43 (7) ◽  
pp. 537-546
Author(s):  
Heejong Son ◽  
Sangki Choi ◽  
Byungryul An ◽  
Hyejin Lee ◽  
Hoon-Sik Yoom
Keyword(s):  
Molecular Weight ◽  
Organic Matter ◽  
Activated Carbon ◽  
Pore Structure ◽  
Adsorption Capacity ◽  
Natural Organic Matter ◽  
Volume Ratio ◽  
The Other ◽  
Low Molecular Weight ◽  
Thermal Regeneration

Objectives : The purpose of this study was to evaluate the effect of increasing the number of regeneration of granular activated carbon (GAC) on the adsorption capacity of natural organic matter (NOM), and to suggest the technical process options associated the limit number of regeneration and the efficient use of regenerated GAC.Methods : The physicochemical properties of virgin and thermally regenerated GAC were analyzed. To evaluate the NOM adsorption capacity of virgin- and regenerated-GAC, five laboratory-scale columns packed with virgin- and regenerated-GAC were used for treating effluent from pilot-scale drinking water treatment facility. The NOM concentration in the influent and the effluent treated by each column was analyzed by LC-OCD (liquid chromatography-organic carbon detector) to evaluate the adsorption capacity of each NOM fractions (humic substances (HS), building blocks (BB), low molecular weight organics (LMWs)).Results and Discussion : Due to the change in the pore structure of GAC by thermal regeneration, the volume of micropores (< 2 nm) decreased, while the volume of mesopores (> 2 nm) increased. The volume ratio of micropore in virgin-GAC was about 60%, but it gradually decreased as the number of regenerations increased, resulting that the volume ratio of micropore in the 5th-regenerated (5th-Re) GAC decreased to 23%. On the other hand, the volume ratio of mesopore increased in proportion to the number of regenerations from 40% of the virgin GAC to 77% of the 5th-Re-GAC. The DOC adsorption capacities of the regenerated GACs were higher than that of virgin GAC, and the DOC adsorption capacity increased as the number of regenerations increased. As a result of comparing the adsorption capacity of virgin- and regenerated-GAC by NOM fractions, the adsorption capacity of high molecular weight NOM, such as HS, increased by 1.5 to 1.7 times as the number of regenerations increased. In contrast, the adsorption capacity of low molecular weight NOM, such as BB and LMWs, decreased by 78% and 48% as the number of regeneration increased. The limit number of regeneration was evaluated based on that the adsorption capacity (qe) of each NOM fractions keep over than 70% relative to its virgin GAC. As a result, the adsorption capacity for low molecular weight NOM was greatly reduced in GAC regenerated over than 3rd time, so that the 2nd-Re-GAC was valid to keep 70% removal of whole NOM fractions. Low adsorption of low molecular weight NOM (BB and LMWs) by 3rd-Re-GAC could be complemented by using together with virgin-GAC, and low adsorption of high molecular NOMs (HS) could be compensated as well.Conclusions : Due to the change in the pore structure of GAC by thermal regeneration, the DOC adsorption capacity was higher in regenerated GAC than its virgin-GAC, and the adsorption capacity of DOC and high molecular weight NOM (HS) was enhanced as the number of regenerations increased. On the other hand, the pore volume of micropore was reduced by regenerations, and in more than 3rd times regenerations, the adsorption capacity of low molecular weight NOMs (BB and LMWs) was reduced by less than 70% compared to its virgin GAC, so that 2nd-Re-GAC was suggested for suitable GAC. When using a mixture of virgin- and 3rd-Re-GAC, low adsorption of low molecular weight NOM (BB and LMWs) by 3rd-Re-GAC could be complemented by using together with virgin-GAC, and low adsorption of high molecular NOMs (HS) could be compensated as well.

scholarly journals Electroadsorptive Removal of Gaseous Pollutants

2019 ◽  
Vol 9 (6) ◽  
pp. 1162 ◽  
Author(s):  
Mattia Pierpaoli ◽  
Gabriele Fava ◽  
Maria Ruello
Keyword(s):  
Activated Carbon ◽  
Electric Field ◽  
Adsorption Capacity ◽  
Adsorption Kinetics ◽  
Applied Electric Field ◽  
Carbon Cloth ◽  
Activated Carbon Cloth ◽  
Enhanced Adsorption ◽  
Electrohydrodynamic Force ◽  
Kinetics Of

Adsorption is a consequence of surface energy distribution, and the existence of electrostatic bonding suggests that the presence of an external electric field may affect adsorbate/adsorbent interactions. Nevertheless, this aspect has been poorly studied in the literature, except under non-thermal plasma or corona discharge conditions. After having demonstrated in our previous work that the adsorption kinetics of gaseous organic compounds can be enhanced by the presence of an external applied electric field, in this study, we focus on the influence of the electric field on adsorbent and adsorptive interactions. By using a commercially available activated carbon cloth, in addition to increasing the adsorbent mass transfer coefficient by virtue of the increasing intensity of the applied electric field, the results suggest that adsorbent morphology is only influenced by the formation of new surface functional groups. Moreover, enhanced adsorption kinetics and capacity may result from the electrohydrodynamic force induced by the movement of charged and neutral particles towards the adsorbent, as confirmed by the reversibility of the process. Such enhancement results in a negligible increase, of about 3%, in adsorption capacity (i.e., from 91 mmol m−2 Pa−1 for only adsorption to 94 mmol m−2 Pa−1 in the presence of the applied electric field), but also in a dramatic doubling of adsorption kinetics (i.e., from 0.09 min−1 for only adsorption to 0.19 min−1 in the presence of the applied electric field). In reality, the application of an electric field to an activated carbon cloth leads to faster adsorption kinetics, without substantially altering its adsorption capacity.

Biocompatible magnetic N-rich activated carbon from egg white biomass and sucrose: Preparation, characterization and investigation of dye adsorption capacity from aqueous solution

2019 ◽  
Vol 15 ◽  
pp. 157-165 ◽  
Author(s):  
Saleh Vahdati-Khajeh ◽  
Maryam Zirak ◽  
Roghaye Zooghi Tejrag ◽  
Asra Fathi ◽  
Kamran Lamei ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Adsorption Capacity ◽  
Dye Adsorption ◽  
Egg White

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

2020 ◽  
Vol 3 (6) ◽  
pp. 841-856
Author(s):  
Cecile Andre Stanford ◽  
Majeda Khraisheh ◽  
Fares Al Momani ◽  
Ahmad B. Albadarin ◽  
Gavin M. Walker ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Activated Carbon ◽  
Adsorption Capacity ◽  
Surface Area ◽  
Water Hardness ◽  
Freundlich Isotherm ◽  
Lower Surface ◽  
Activated Alumina ◽  
Isotherm Study ◽  
Beta Form

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.

scholarly journals Adsorption of Congo red dye onto antimicrobial terephthaloyl thiourea cross-linked chitosan hydrogels

2017 ◽  
Vol 76 (10) ◽  
pp. 2719-2732 ◽  
Author(s):  
Nouf F. El-Harby ◽  
Shaimaa M. A. Ibrahim ◽  
Nadia A. Mohamed
Keyword(s):  
Adsorption Capacity ◽  
Congo Red ◽  
Dye Adsorption ◽  
Solution Temperature ◽  
Structural Variations ◽  
Maximum Sorption Capacity ◽  
Congo Red Dye ◽  
Chitosan Hydrogels ◽  
Red Dye ◽  
Kinetics And Isotherms

Abstract Adsorption capacity of three antimicrobial terephthaloyl thiourea cross-linked chitosan hydrogels for Congo red dye removal from its aqueous solution has been investigated for the first time in this work. These hydrogels were prepared by reacting chitosan with various amounts of terephthaloyl diisothiocyanate cross-linker. The effect of the hydrogel structural variations and several dye adsorption processing parameters to achieve the best adsorption capacity were investigated. The hydrogels' structural variations were obtained by varying their terephthaloyl thiourea moieties content. The processing variables included initial concentration of the dye solution, temperature and time of exposure to the dye. The adsorption kinetics and isotherms showed that the sorption processes were better fitted by the pseudo-second-order equation and the Langmuir equation, respectively. On the basis of the Langmuir analysis Congo red dye gave the maximum sorption capacity of 44.248 mg/g. The results obtained confirmed that the sorption phenomena are most likely to be controlled by chemisorption process. The adsorption reaction was endothermic and spontaneous according to the calculated results of adsorption thermodynamics.

scholarly journals Adsorption of Crystal Violet Dye Using Activated Carbon of Lemon Wood and Activated Carbon/Fe3O4 Magnetic Nanocomposite from Aqueous Solutions: A Kinetic, Equilibrium and Thermodynamic Study

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2241
Author(s):  
Rauf Foroutan ◽  
Seyed Jamaleddin Peighambardoust ◽  
Seyed Hadi Peighambardoust ◽  
Mirian Pateiro ◽  
Jose M. Lorenzo
Keyword(s):  
Activated Carbon ◽  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Crystal Violet ◽  
Fe3o4 Nanoparticles ◽  
Adsorption Process ◽  
Dye Adsorption ◽  
Magnetic Nanocomposite ◽  
Maximum Adsorption Capacity ◽  
Adsorption Enthalpy

Activated carbon prepared from lemon (Citrus limon) wood (ACL) and ACL/Fe3O4 magnetic nanocomposite were effectively used to remove the cationic dye of crystal violet (CV) from aqueous solutions. The results showed that Fe3O4 nanoparticles were successfully placed in the structure of ACL and the produced nanocomposites showed superior magnetic properties. It was found that pH was the most effective parameter in the CV dye adsorption and pH of 9 gave the maximum adsorption efficiency of 93.5% and 98.3% for ACL and ACL/Fe3O4, respectively. The Dubinin–Radushkevich (D-R) and Langmuir models were selected to investigate the CV dye adsorption equilibrium behavior for ACL and ACL/Fe3O4, respectively. A maximum adsorption capacity of 23.6 and 35.3 mg/g was obtained for ACL and ACL/Fe3O4, respectively indicating superior adsorption capacity of Fe3O4 nanoparticles. The kinetic data of the adsorption process followed the pseudo-second order (PSO) kinetic model, indicating that chemical mechanisms may have an effect on the CV dye adsorption. The negative values obtained for Gibb’s free energy parameter (−20 < ΔG < 0 kJ/mol) showed that the adsorption process using both types of the adsorbents was physical. Moreover, the CV dye adsorption enthalpy (ΔH) values of −45.4 for ACL and −56.9 kJ/mol for ACL/Fe3O4 were obtained indicating that the adsorption process was exothermic. Overall, ACL and ACL/Fe3O4 magnetic nanocomposites provide a novel and effective type of adsorbents to remove CV dye from the aqueous solutions.

Aerobic granular sludge-derived activated carbon: mineral acid modification and superior dye adsorption capacity

RSC Advances ◽  
2015 ◽  
Vol 5 (32) ◽  
pp. 25279-25286 ◽  
Author(s):  
Ge Zhang ◽  
Li Shi ◽  
Yongfang Zhang ◽  
Dong Wei ◽  
Tao Yan ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Sulfuric Acid ◽  
Nitric Acid ◽  
Adsorption Capacity ◽  
Zinc Chloride ◽  
Dye Adsorption ◽  
Granular Sludge ◽  
Mineral Acid ◽  
Aerobic Granular Sludge ◽  
Acid Modification

A novel aerobic granular sludge-derived activated carbon (AC) was prepared by a zinc chloride activation method and further modified by mineral acid (nitric acid (NA) and sulfuric acid (SA)).

Sign in / Sign up

Export Citation Format

Share Document