Outstanding Performance of a New Exfoliated Clay Impregnated with Rutile TiO2 Nanoparticles Composite for Dyes Adsorption: Experimental and Theoretical Studies

Pure rutile TiO2 nanoparticles (Rt) were combined with exfoliated black clay (BC) to prepare a new composite for water decontamination, in particular, for the uptake of methylene blue (MB) and methyl orange (MO) dyes. The as-prepared Rt/BC was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Field emission scanning electron microscopy (FESEM) techniques, and the dyes’ adsorption isotherms at three temperatures (i.e., 25, 40, and 50 °C) were studied. The results indicated that Rt/BC displayed a high removal performance for MO (96.7%) and MB (91.4%) at pH 3.0 and 8.0, respectively. Adsorption data of MB and MO were adjusted by a double layer model at all temperatures. The theoretical parameters of this statistical physics model were interpreted to understand the MO and MB adsorption mechanisms at the molecular level. The removed molecules per active site (n) of Rt/BC ranged from 1.12 to 1.29 for MB and 1.47 to 1.85 for MO, thus representing parallel orientation and multi-interactions mechanisms (i.e., van der Waals forces, hydrogen bonding, and electrostatic interactions were involved). The Rt/BC composite had a density of surface adsorption sites of 100 mg/g. The aggregation of MO molecules was high and increased their adsorption capacities (Qsat = 294–370 mg/g) compared to that of MB (Qsat = 214–249 mg/g). Adsorption energies were 9.70–20.15 kJ/mol, and these values indicated that MO and MB adsorption processes were endothermic and occurred via physical interactions. Overall, the low cost, high regeneration performance, and stability of Rt/BC support its application as a promising adsorbent for organic pollutants from wastewaters.

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Irreversible sorption of Pb(II) from aqueous solution on breadfruit peel to mitigate environmental pollution problems

Water Science & Technology ◽

10.2166/wst.2019.414 ◽

2019 ◽

Vol 80 (12) ◽

pp. 2241-2249

Author(s):

Namal Priyantha ◽

Linda B. L. Lim ◽

Nur Hakimah Mohd Mansor ◽

Anushka B. Liyandeniya

Keyword(s):

Environmental Pollution ◽

Low Cost ◽

Error Function ◽

Isotherm Models ◽

Artocarpus Altilis ◽

Adsorption Mechanisms ◽

Adsorption Sites ◽

Pseudo Second Order ◽

Optimized Conditions ◽

Kinetics Of

Abstract Development of efficient and environmentally friendly methods to remove toxic pollutants from aqueous systems is a requirement to mitigate ever increasing environmental pollution problems. In this context, Artocarpus altilis (breadfruit) peel (BP), a waste material, can be used as a low-cost adsorbent for the removal of Pb(II) ions from synthetic pollutant solutions. The extent of removal of Pb(II), under optimized conditions in experimental batch experiments, is determined to be 82.0%, which is decreased in highly ionic environments, partly due to competition for a limited number of active adsorption sites, indicating the necessity of optimizing experimental parameters for the most efficient removal. Regression analysis and error function values evaluated for isotherm models associated with different adsorption mechanisms, namely Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, Redlich–Peterson and Sips, indicate that the best fitted model is the Sips followed by the Langmuir model with adsorption capacities (qmax) of 78.50 mg g−1 and 85.42 mg g−1, respectively. Thermodynamics arguments support the spontaneous and exothermic behavior of the Pb(II)-BP adsorption system, while adsorption kinetics of the system provides evidence for the applicability of the pseudo second order model with a rate constant of 0.504 g mg−1 min−1.

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Experimental and Theoretical Insights on Methylene Blue Removal from Wastewater Using an Adsorbent Obtained from the Residues of the Orange Industry

Molecules ◽

10.3390/molecules26154555 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4555

Author(s):

Stephanie Giraldo ◽

Irma Robles ◽

Luis A. Godínez ◽

Nancy Acelas ◽

Elizabeth Flórez

Keyword(s):

Methylene Blue ◽

Aqueous Solutions ◽

Electrostatic Interactions ◽

Density Functional ◽

Theoretical Study ◽

Orange Peel ◽

Good Alternative ◽

Functional Theory ◽

Adsorption Mechanisms ◽

Mb Adsorption

Chemical and thermochemical transformations were performed on orange peel to obtain materials that were characterized and further tested to explore their potential as adsorbents for the removal of methylene blue (MB) from aqueous solutions. The results show the high potential of some of these materials for MB adsorption not only due to the surface area of the resulting substrate but also to the chemistry of the corresponding surface functional groups. Fitting of the kinetic as well as the equilibrium experimental data to different models suggests that a variety of interactions are involved in MB adsorption. The overall capacities for these substrates (larger than 192.31 mg g−1) were found to compare well with those reported for activated carbon and other adsorbents of agro-industrial origin. According to these results and complementary with theoretical study using Density Functional Theory (DFT) approximations, it was found that the most important adsorption mechanisms of MB correspond to: (i) electrostatic interactions, (ii) H-bonding, and (iii) π (MB)–π (biochar) interactions. In view of these findings, it can be concluded that adsorbent materials obtained from orange peel, constitute a good alternative for the removal of MB dye from aqueous solutions.

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Comparison of the fixation of several metal ions onto a low-cost biopolymer

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0172 ◽

2002 ◽

Vol 2 (5-6) ◽

pp. 217-224 ◽

Cited By ~ 6

Author(s):

Z. Reddad ◽

C. Gérente ◽

Y. Andrès ◽

P. Le Cloirec

Keyword(s):

Aqueous Solutions ◽

Metal Ions ◽

Low Cost ◽

Operating Conditions ◽

Order Kinetic ◽

Adsorption Mechanisms ◽

Equilibrium Data ◽

Order Kinetic Model ◽

Beet Pulp ◽

Removal Of Metal Ions

In the present work, sugar beet pulp, a common waste from the sugar refining industry, was studied in the removal of metal ions from aqueous solutions. The ability of this cheap biopolymer to sorb several metals namely Pb2+, Cu2+, Zn2+, Cd2+ and Ni2+ in aqueous solutions was investigated. The metal fixation capacities of the sorbent were determined according to operating conditions and the fixation mechanisms were identified. The biopolymer has shown high elimination rates and interesting metal fixation capacities. A pseudo-second-order kinetic model was tested to investigate the adsorption mechanisms. The kinetic parameters of the model were calculated and discussed. For 8 × 10-4 M initial metal concentration, the initial sorption rates (v0) ranged from 0.063 mmol.g-1.min-1 for Pb2+ to 0.275 mmol.g-1.min-1 for Ni2+ ions, with the order: Ni2+ > Cd2+ > Zn2+ > Cu2+ > Pb2+. The equilibrium data fitted well with the Langmuir model and showed the following affinity order of the material: Pb2+ > Cu2+ > Zn2+ > Cd2+ > Ni2+. Then, the kinetic and equilibrium parameters calculated qm and v0 were tentatively correlated to the properties of the metals. Finally, equilibrium experiments in multimetallic systems were performed to study the competition of the fixation of Pb2+, Zn2+ and Ni2+ cations. In all cases, the metal fixation onto the biopolymer was found to be favourable in multicomponent systems. Based on these results, it is demonstrated that this biosorbent represents a low-cost solution for the treatment of metal-polluted wastewaters.

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Mechanisms and adsorption capacities of biochar for the removal of organic and inorganic pollutants from industrial wastewater

International Journal of Environmental Science and Technology ◽

10.1007/s13762-020-03060-w ◽

2020 ◽

Author(s):

T. G. Ambaye ◽

M. Vaccari ◽

E. D. van Hullebusch ◽

A. Amrane ◽

S. Rtimi

Keyword(s):

Organic Contaminants ◽

Pyrolysis Temperature ◽

Low Cost ◽

Industrial Effluents ◽

Economic Benefits ◽

Inorganic Pollutants ◽

Solution Ph ◽

Adsorption Mechanisms ◽

Adsorption Capacities ◽

Temperature Solution

AbstractCurrently, due to the rapid growth of urbanization and industrialization in developing countries, a large volume of wastewater is produced from industries that contain chemicals generating high environmental risks affecting human health and the economy if not treated properly. Consequently, the development of a sustainable low-cost wastewater treatment approach has attracted more attention of policymakers and scientists. The present review highlights the recent applications of biochar in removing organic and inorganic pollutants present in industrial effluents. The recent modes of preparation, physicochemical properties and adsorption mechanisms of biochar in removing organic and inorganic industrial pollutants are also reviewed comprehensively. Biochar showed high adsorption of industrial dyes up to 80%. It also discusses the recent application and mechanism of biochar-supported photocatalytic materials for the degradation of organic contaminants in wastewater. We reviewed also the possible optimizations (such as the pyrolysis temperature, solution pH) allowing the increase of the adsorption capabilities of biochar leading to organic contaminants removal. Besides, increasing the pyrolysis temperature of the biochar was seen to lead to an increase in its surface area, while it decreases their amount of oxygen-containing functional groups, consequently leading to a decrease in the adsorption of metal (loid) ions present in the medium. Finally, the review suggests that more research should be carried out to optimize the main parameters involved in biochar production and its regeneration methods. Future efforts should be also carried out towards process engineering to improve its adsorption capacity to increase the economic benefits of its implementation.

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Sol-gel synthesized rutile TiO2 nanoparticles loaded with Cardamom essential oil: Enhanced antibacterial activity

Journal of Drug Delivery Science and Technology ◽

10.1016/j.jddst.2021.102581 ◽

2021 ◽

pp. 102581

Author(s):

Oussama Ouerghi ◽

Mohammed H. Geesi ◽

Elmutasim O. Ibnouf ◽

Mohammad Javed Ansari ◽

Pravej Alam ◽

...

Keyword(s):

Antibacterial Activity ◽

Essential Oil ◽

Tio2 Nanoparticles ◽

Sol Gel ◽

Rutile Tio2

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Implementation of a multilayer statistical physics model to interpret the adsorption of food dyes on a chitosan film

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2021.105516 ◽

2021 ◽

pp. 105516

Author(s):

Lotfi Sellaoui ◽

Fatma Dhaouadi ◽

Zichao Li ◽

Tito R.S. Cadaval ◽

Andrei V. Igansi ◽

...

Keyword(s):

Statistical Physics ◽

Chitosan Film ◽

Food Dyes ◽

Physics Model ◽

Statistical Physics Model

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Interpreting the hydrogen adsorption on organic groups functionalized MOF-5s by statistical physics model

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2017.01.149 ◽

2017 ◽

Vol 42 (15) ◽

pp. 10023-10037 ◽

Cited By ~ 3

Author(s):

Sarra Wjihi ◽

Jie Yang ◽

Lotfi Sellaoui ◽

Salah Knani ◽

Abdelmottaleb Ben Lamine

Keyword(s):

Statistical Physics ◽

Hydrogen Adsorption ◽

Physics Model ◽

Statistical Physics Model

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Preparation and Photocatalytic Activity of Mixed Phase Anatase/rutile TiO2 Nanoparticles for Phenol Degradation

Jurnal Teknologi ◽

10.11113/jt.v70.3437 ◽

2014 ◽

Vol 70 (2) ◽

Author(s):

Mohamad Azuwa Mohamed ◽

Wan Norharyati Wan Salleh ◽

Juhana Jaafar ◽

Norhaniza Yusof

Keyword(s):

Photocatalytic Activity ◽

Tio2 Nanoparticles ◽

High Performance ◽

Sol Gel ◽

Phenol Degradation ◽

Chemical Properties ◽

Mixed Phase ◽

Rutile Tio2 ◽

Physico Chemical ◽

Degussa P25

The evolution of desirable physico-chemical properties in high performance photocatalyst materials involves steps that must be carefully designed, controlled, and optimized. This study investigated the role of key parameter in the preparation and photocatalytic activity analysis of the mixed phase of anatase/rutile TiO2 nanoparticles, prepared via sol-gel method containing titanium-n-butoxide Ti(OBu)4 as a precursor material, nitric acid as catalyst, and isopropanol as solvent. The prepared TiO2 nanoparticles were characterized by means of XRD, SEM, and BET analyses, and UV-Vis-NIR spectroscopy. The results indicated that the calcination temperature play an important role in the physico-chemical properties and photocatalytic activity of the resulting TiO2 nanoparticles. Different calcination temperatures would result in different composition of anatase and rutile. The photocatalytic activity of the prepared mixed phase of anatase/rutile TiO2 nanoparticles was measured by photodegradation of 50 ppm phenol in an aqueous solution. The commercial anatase from Sigma-Aldrich and Degussa P25 were used for comparison purpose. The mixed phase of anatase/rutile TiO2 nanoparticles (consists of 38.3% anatase and 61.7% rutile) that was prepared at 400°C exhibited the highest photocatalytic activity of 84.88% degradation of phenol. The result was comparable with photocatalytic activity demonstrated by Degussa P25 by 1.54% difference in phenol degradation. The results also suggested that the mixed phase of anatase/rutile TiO2 nanoparticles is a promising candidate for the phenol degradation process. The high performance of photocatalyst materials may be obtained by adopting a judicious combination of anatase/rutile and optimized calcination conditions.

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