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Preparation and Characterization of Porous Carbon@ZnO‐NPs for Organic Compounds Removal: Classical Adsorption Versus Ultrasound Assisted Adsorption

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Authors:
Zakaria Anfar at Institut de Science des Matériaux de Mulhouse
Zakaria Anfar
Mohamed Zbair at Université de Haute-Alsace
Mohamed Zbair
Hassan Ait Ahsaine
Hassan Ait Ahsaine
Hassan Ait Ahsaine
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Youness Abdellaoui at Center for Research and Advanced Studies of the National Polytechnic Institute
Youness Abdellaoui
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Abstract and Figures

In this paper, the synthesis and characterization of porous carbon (PC) and porous carbon loaded ZnO nanoparticles (PC@ZnO) were investigated. The removal efficiency of Methylene Blue (MB) under ultrasound waves (UAA) and without ultrasound waves (SA) was studied considering the adsorbents dose, contact time, solution pH, temperature and initial dye concentration. Ultrasound irradiation have a positive effect on the removal efficiency of MB whereas ZnO nanoparticles incorporate in the surface of PC improve the regeneration efficiency of PC. PC@ZnO NPs shows high performance of MB removal using UAA, which was used for simultaneous removal of Crystal Violet (CV) and Congo Red (CR). The ultrasonic adsorption of CV/CR on PC@ZnO was found to be dependent on different parameters such as contact time, solution pH and initial dye concentration. The experimental results were found to follow the pseudo‐second‐order and Langmuir models. The adsorbed amount was found to be 64 mg g⁻¹ (for CR) and 109 mg g⁻¹ (for CV). Further, the effects of various parameters such as contact time, pH, initial dye concentration, and CV:CR ratio, were studied using central composite design coupled with response surface methodology. The data showed that the PC@ZnO has strong selective adsorption of CV dye in comparison to CR, and optimum conditions were found to be natural pH, 11.19 mg, (55:45%) of CV:CR ratio, 25 min and 30 mg L⁻¹ at adsorption temperature T=25 °C ± 1. In these conditions, both dyes (CV and CR) are easily regenerated using HCl (0.1 M).
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zSustainable Chemistry
Preparation and Characterization of Porous
Carbon@ZnO-NPs for Organic Compounds Removal:
Classical Adsorption Versus Ultrasound Assisted Adsorption
Zakaria Anfar,*[a, b, c] Mohamed Zbair,[d] Hassan Ait Ahsaine+,[a] Youness Abdellaoui,[e]
Abdellah Ait El Fakir,[a] El Hassan Amaterz,[a] Amane Jada,*[b, c] and Noureddine El Alem[a]
In this paper, the synthesis and characterization of porous
carbon (PC) and porous carbon loaded ZnO nanoparticles
(PC@ZnO) were investigated. The removal efficiency of
Methylene Blue (MB) under ultrasound waves (UAA) and
without ultrasound waves (SA) was studied considering the
adsorbents dose, contact time, solution pH, temperature and
initial dye concentration. Ultrasound irradiation have a positive
effect on the removal efficiency of MB whereas ZnO nano-
particles incorporate in the surface of PC improve the
regeneration efficiency of PC. PC@ZnO NPs shows high
performance of MB removal using UAA, which was used for
simultaneous removal of Crystal Violet (CV) and Congo Red
(CR). The ultrasonic adsorption of CV/CR on PC@ZnO was found
to be dependent on different parameters such as contact time,
solution pH and initial dye concentration. The experimental
results were found to follow the pseudo-second-order and
Langmuir models. The adsorbed amount was found to be
64 mg g1(for CR) and 109 mg g1(for CV). Further, the effects
of various parameters such as contact time, pH, initial dye
concentration, and CV:CR ratio, were studied using central
composite design coupled with response surface methodology.
The data showed that the PC@ZnO has strong selective
adsorption of CV dye in comparison to CR, and optimum
conditions were found to be natural pH, 11.19 mg, (55:45%) of
CV:CR ratio, 25 min and 30 mg L1at adsorption temperature
T=25°C�1. In these conditions, both dyes (CV and CR) are
easily regenerated using HCl (0.1 M).
Introduction
Dyes are considered as hazardous pollutants causing serious
environmental problems because of their toxicity, carcinogenic-
ity and mutagenic properties, which threatens aquatic life and
humans even at low concentrations.[1] Many industrial activities
discharge colored wastewaters, including dye manufacturing,
tanneries, paper, leather, plastic, and food processing. There-
fore, it is important to tackle this problem and find effective
alternatives and techniques to treat colored wastewaters before
being discharged into the environment aqueous solutions.
Different physicochemical methods including adsorption,
chemical oxidation, coagulation, flocculation, and photocata-
lytic reactions have been tested for the treatment of waste-
water colored by dyes.[2–4] It is noteworthy to note that
magnetic and dielectric oxides have been also used for
environmental remediation.[5–7] Among the techniques used for
environmental, adsorption using solid adsorbents has gained
particular attention among the worldwide researchers as being
highly efficient, of low operating cost with a simple operation
process and capable for large scale pollutants removal.[8–13]
Commercial activated carbon, clays and zeolites are the most
important adsorbents that have been used so far.[14–17] However,
the use of commercially synthesized adsorbents for the
adsorption process has become limited and restricted since
they exhibit some drawbacks like high production costs, poor
regeneration ability.
Combining the ultrasound irradiation and adsorption
process has received much more attention.[18] This combination
is believed to accelerate the chemical reactions and mass
transfer because of the creation of new adsorption sites on the
adsorbent and acoustic cavitation. Besides, the ultrasonic
waves create microscopic turbulence through the solid par-
ticles generating final acoustic streaming and break the affinity
[a] Dr. Z. Anfar, Dr. H. A. Ahsaine,+Dr. A. A. El Fakir, Prof. E. H. Amaterz,
Prof. N. El Alem
Materials and environment laboratory, Ibn Zohr University, Agadir, 8000,
Morocco
E-mail: zakaria.anfar@uha.fr
[b] Dr. Z. Anfar, Dr. A. Jada
Mulhouse materials science institute - CNRS, University Haute Alsace, F-
68100, Mulhouse, France
E-mail: zakaria.anfar@uha.fr
amane.jada@uha.fr
[c] Dr. Z. Anfar, Dr. A. Jada
University of Strasbourg, Strasbourg, F-67081, France
E-mail: zakaria.anfar@uha.fr
amane.jada@uha.fr
[d] Dr. M. Zbair
Laboratoire de Catalyse et Corrosion des Matériaux LCCM, Université
Chouaib Doukkali, Faculté des Sciences El Jadida, BP. 20, El Jadida 24000
Morocco
[e] Dr. Y. Abdellaoui
Facultad de Ingeniería, Universidad Autónoma de Yucatán, Av. Industrias
no Contaminantes por Periférico Norte Apartado Postal 150 Cordemex,
97310 Mérida, Yucatán, México
[+]Present address: King Abdullah University of Science and Technology
(KAUST), Division of Physical Science and Engineering (PSE)
Supporting information for this article is available on the WWW under
https://doi.org/10.1002/slct.201901043
Full PapersDOI: 10.1002/slct.201901043
4981
ChemistrySelect 2019,4, 4981–4994 © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Wiley VCH Dienstag, 30.04.2019
1917 / 135776 [S. 4981/4994] 1
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  • Jun 2018
  • ULTRASON SONOCHEM
In this study, the impact of ultrasound on the adsorption and desorption features of blueberry anthocyanins on macroporous resins were studied. Sonication was performed at 106-279 W/L and 20-30 °C in a pulsed mode, respectively. Generally, ultrasound treatments within the selected experimental range enhanced the adsorption/desorption process of anthocyanins on macroporous resins. The recovery of blueberry anthocyanins after ultrasound-assisted adsorption/desorption process at 279 W/L and 20 °C was 82.12%, which was 52.84% higher than that obtained after adsorption/desorption with shaking at 100 rpm. Meanwhile, higher acoustic energy density (AED) levels and lower temperatures benefited the adsorption process through enhancing the adsorption capacity and shortening the equilibrium time, whereas higher temperatures promoted the desorption process. Furthermore, malvidin-3-galactoside had the highest adsorption and desorption capacities among all the studied monomeric anthocyanins. No organic acids and sugars were detected after adsorption/desorption processes, indicating the successful improvement of anthocyanin purification. Sonication mainly enhanced the adsorption process by means of strengthening the formation of hydrogen bond on resins surface and increasing their surface roughness. Overall, ultrasound can be an effective tool to improve the purification of anthocyanins using macroporous resins.
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Cationic dyes adsorption onto high surface area ‘almond shell’ activated carbon: Kinetics, equilibrium isotherms and surface statistical modeling
Article
  • Mar 2018
Almond shell agricultural biomass was used to prepare high surface area activated carbon using potassium hydroxide as activating agent. The activated carbon (AC) was characterized using X-Ray photoelectron spectroscopy, X-Ray diffraction, Thermogravimetric and differential thermal analyses, Scanning electron microscopy, Fourier transform infrared, Brunauer–Emmett–Teller surface area and Raman spectroscopy. The AC was found to have a high surface area of 2054 m2 g− 1. The influence of various key parameters was evaluated on the adsorption process including contact time, adsorbent dose and solution pH. Isotherm data were modeled using Langmuir and Freundlich models. Langmuir isotherm model presented the best fit to experimental data suggesting homogeneous distribution of adsorption sites. The adsorbent demonstrated high monolayer adsorption capacity of 833.33 and 625.0 mg/g for Methylene Blue and Crystal Violet, respectively. The efficiency of the adsorption process was linked to the micro-mesoporous structure and to the availability of the surface adsorption sites. Response surface methodology was used to optimize the removal efficiency from aqueous solution.
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Hierarchically Designed Nickel-Entangled Carbon Sphere with Superior Adsorption Properties
Article
  • Mar 2018
In this work, a C@Ni hierarchical structure was carefully designed by entangling carbon microspheres with curving nickel nanosheets. The presence of copious mesopores between adjoining nanosheets and microspheres greatly enhanced the specific surface area from 314.7 m² g⁻¹ for pristine carbon spheres to 448.7 m² g⁻¹ for this well-designed C@Ni architecture. This salient structural feature enabled it as an ideal magnetic adsorbent for CrVI removal in wastewater. The high CrVI adsorption capacity of ca. 550 mg g⁻¹ at 298 K, remarkable adsorption rate of 3.38 mg g⁻¹ min⁻¹ and excellent regeneration efficiencies above 90% were highly desirable for its widespread potential applications in water treatment.
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