Adsorptive removal of bulky dye molecules from water with mesoporous polyaniline-derived carbon

Polyaniline-derived carbon (PDC) was obtained via pyrolysis of polyaniline under different temperatures and applied for the purification of water contaminated with dye molecules of different sizes and charge by adsorption. With increasing pyrolysis temperature, it was found that the hydrophobicity, pore size and mesopore volume increased. A mesoporous PDC sample obtained via pyrolysis at 900 °C showed remarkable performance in the adsorption of dye molecules, irrespective of dye charge, especially in the removal of bulky dye molecules, such as acid red 1 (AR1) and Janus green B (JGB). For example, the most competitive PDC material showed a Q 0 value (maximum adsorption capacity) 8.1 times that of commercial, activated carbon for AR1. The remarkable adsorption of AR1 and JGB over KOH-900 could be explained by the combined mechanisms of hydrophobic, π–π, electrostatic and van der Waals interactions.

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Adsorption of Hexavalent Chromium Using Banana Pseudostem Biochar and Its Mechanism

Sustainability ◽

10.3390/su10114250 ◽

2018 ◽

Vol 10 (11) ◽

pp. 4250 ◽

Cited By ~ 12

Author(s):

Shuang Xu ◽

Weiguang Yu ◽

Sen Liu ◽

Congying Xu ◽

Jihui Li ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Pyrolysis Temperature ◽

Low Cost ◽

Surface Adsorption ◽

Maximum Adsorption Capacity ◽

X Ray ◽

Adsorption Processes ◽

Different Temperatures ◽

Pseudo Second Order ◽

Porosity Analysis

A low-cost biochar was prepared through slow pyrolysis of banana pseudostem biowaste at different temperatures, and characterized by surface area and porosity analysis, scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). It was shown that the biochar prepared at low pyrolysis temperature was rich in oxygen-containing groups on the surface. Adsorption experiments revealed that the biochar prepared at 300 °C (BB300) was the best adsorbent for Cr(VI) with 125.44 mg/g maximum adsorption capacity at pH 2 and 25 °C. All the adsorption processes were well described by pseudo-second-order and Langmuir models, indicating a monolayer chemiadsorption. Furthermore, it was demonstrated that adsorption of Cr(VI) was mainly attributed to reduction of Cr(VI) to Cr(III) followed by ion exchange and complexation with the biochar.

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A study on the removal of prednisone from aqueous solutions by adsorption onto a vegetal activated carbon

Water Science & Technology ◽

10.2166/wst.2018.515 ◽

2018 ◽

Vol 78 (11) ◽

pp. 2328-2337 ◽

Cited By ~ 1

Author(s):

Jéssica C. Zanette ◽

Márcia T. Veit ◽

Gilberto C. Gonçalves ◽

Soraya M. Palácio ◽

Fernando R. Scremin ◽

...

Keyword(s):

Experimental Data ◽

Activated Carbon ◽

Aqueous Solutions ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Order Model ◽

Different Temperatures ◽

Increasing Temperature ◽

Central Composite ◽

Adsorbent Dose

Abstract This study evaluated the prednisone removal from aqueous solutions using adsorption by an activated carbon of vegetal origin (VAC). A central composite rotatable design (CCRD) and the response surface methodology (RSM) were used to verify the influence of the parameters: pH, adsorbent dose and prednisone concentration in a batch adsorption process. Among the analyzed parameters, only the adsorbent dose and the prednisone concentration were statistically significant (α = 0.05) and the critical values obtained were adsorbent dose: 1.87 g/L, pH 7.56 and prednisone concentration: 3.66 mg/L with 77.51% of prednisone removal by VAC. The kinetic study of the adsorption of prednisone reached the equilibrium in 4 h. The pseudo-first-order model described adequately the kinetics data behavior. The equilibrium experimental data obtained at different temperatures showed that the VAC has a maximum adsorption capacity of 18.04 mg/g at a temperature of 30 °C. The prednisone removal decreased by the increasing temperature and the Langmuir isotherm well described the experimental data (R² > 0.98). Thermodynamic results shown that the prednisone removal of aqueous solutions by VAC is spontaneous and favorable process.

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Effect of Pyrolysis Temperature During Valorization of Date Stones on Physiochemical Properties of Activated Carbon and Its Catalytic Activity for the Oxidation of Cycloalkenes

Catalysts ◽

10.3390/catal11060686 ◽

2021 ◽

Vol 11 (6) ◽

pp. 686

Author(s):

Hamed M. Alshammari ◽

Nadir Abbas

Keyword(s):

Catalytic Activity ◽

Activated Carbon ◽

Calcination Temperature ◽

Pyrolysis Temperature ◽

Catalytic Properties ◽

Kingdom Of Saudi Arabia ◽

Physiochemical Properties ◽

Pyrolysis Method ◽

Different Temperatures ◽

The Impact

This study presents findings on the chemical synthesis of activated carbon from Saudi dates and its structural, chemical, and catalytic properties. Dates are among the top biowaste materials in the Kingdom of Saudi Arabia, and efforts are underway to utilize this resource. A chemical pyrolysis method was used to synthesize activated carbon from date stones. Synthesized activated carbon was calcined at different temperatures of 400, 500, 600, and 700 °C, and the impact of calcination temperature on the properties of activated carbon was investigated. For this purpose, contemporary characterization tools, namely, XRD, Raman spectroscopy, FTIR, SEM, TEM, TGA, DSC, and XPS, were employed. Results are discussed and compared with associated studies. Finally, the catalytic activity of gold-deposited activated carbon for the oxidation of cycloalkenes was evaluated, and it was found that the calcination temperature has a linear positive relationship with the catalytic activity.

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3,5-Dinitrosalicylic Acid Adsorption Using Granulated and Powdered Activated Carbons

Molecules ◽

10.3390/molecules26226918 ◽

2021 ◽

Vol 26 (22) ◽

pp. 6918

Author(s):

José A. Hernández ◽

Laura Patiño-Saldivar ◽

Alba Ardila ◽

Mercedes Salazar-Hernández ◽

Alfonso Talavera ◽

...

Keyword(s):

Activated Carbon ◽

Active Sites ◽

Activated Carbons ◽

Wine Industry ◽

Maximum Adsorption Capacity ◽

Desorption Process ◽

Adsorbent Surface ◽

Emerging Pollutant ◽

Different Temperatures ◽

Solid Liquid Interface

Some nitroaromatic compounds are found in wastewater from industries such as the weapons industry or the wine industry. One of these compounds is 3,5-dinitrosalicylic acid (DNS), widely used in various tests and frequently found as an emerging pollutant in wastewater and to which the required attention has not been given, even though it may cause serious diseases due to its high toxicity. This study investigated the adsorption of DNS using granulated activated carbon (GAC) and powdered activated carbon (PAC) at different temperatures. The results show that in equilibrium, the adsorption takes place in more than one layer and is favorable for the removal of DNS in both GAC and PAC; The maximum adsorption capacity was obtained at 45 °C, with values of 6.97 mg/g and 11.57 mg/g, respectively. The process is spontaneous and exothermic. In addition, there was a greater disorder in the solid-liquid interface during the desorption process. The predominant kinetics using GAC (7.14 mg/g) as an adsorbent is Elovich, indicating that there are heterogeneous active sites, and when PAC (10.72 mg/g) is used, Pseudo-second order kinetics predominate, requiring two active sites for DNS removal. External mass transfer limitations are only significant in GAC, and ATR-FTIR studies in PAC demonstrated the participation of functional groups present on the adsorbent surface for DNS adsorption.

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Thermodynamics of Formaldehyde Removal by Adsorption onto Nanosilver Loaded Bamboo-Based Activated Carbon

Materials Science Forum ◽

10.4028/www.scientific.net/msf.890.93 ◽

2017 ◽

Vol 890 ◽

pp. 93-97

Author(s):

Wara Dyah Pita Rengga ◽

Sri Wahyuni ◽

Agung Feinnudin

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Adsorption Process ◽

Fixed Bed ◽

Formaldehyde Concentration ◽

Fixed Bed Column ◽

Adsorptive Removal ◽

Formaldehyde Removal ◽

Different Temperatures ◽

Formaldehyde Adsorption

The performance of nanosilver loaded bamboo-based activated carbon as an adsorbent used for the adsorptive removal of formaldehyde in the air. The size porous of the active carbon is predominantly on the size of mesoporous and microporous. Adsorption tests have been evaluated in laboratory scale fixed-bed column, at different temperatures and initial formaldehyde concentration. In order to investigate is both equilibrium and thermodynamic aspects. The experimental data was fitted with Langmuir model and fit well with the adsorption capacity of 91-110 mg/g. The increase in temperature reduces the adsorption capacity. The thermodynamic parameters show that the values of ∆Go obtained to confirm the feasibility of activated carbon effective sorbents of formaldehyde. The formaldehyde adsorption process is exothermic and adsorbent has a good affinity to formaldehyde.

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Purification of water contaminated with heavy metals by example of lead as promising material based on graphene nanostructures

Perspektivnye Materialy ◽

10.30791/1028-978x-2020-9-34-43 ◽

2020 ◽

pp. 34-43

Author(s):

N. R. Memetov ◽

◽

A. V. Gerasimova ◽

A. E. Kucherova ◽

◽

...

Keyword(s):

Adsorption Process ◽

Phenol Formaldehyde ◽

Phenol Formaldehyde Resin ◽

Formaldehyde Resin ◽

Parameter Estimates ◽

Maximum Adsorption Capacity ◽

Ecological Situation ◽

Characteristic Parameters ◽

Purification Of Water ◽

Graphene Nanostructures

The paper evaluates the effectiveness of the use of graphene nanostructures in the purification of lead (II) ions to improve the ecological situation of water bodies. The mechanisms and characteristic parameters of the adsorption process were analyzed using empirical models of isotherms at temperatures of 298, 303, 313 and 323 K, which correspond to the following order (based on the correlation coefficient): Langmuir (0.99) > Temkin (0.97) > Dubinin – Radushkevich (0.90). The maximum adsorption capacity of the material corresponds to the range from 230 to 260 mg/g. We research the equilibrium at the level of thermodynamic parameter estimates, which indicates the spontaneity of the process, the endothermic nature and structure change of graphene modified with phenol-formaldehyde resin during the adsorption of lead (II) ions, leading to an increase in the disorder of the system.

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Activated carbon from molasses efficiency for Cr(VI), Pb(II) and Cu(II) adsorption: A mechanistic study

10.31221/osf.io/ecpm3 ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Activated Carbon ◽

Phosphoric Acid ◽

Sugar Industry ◽

Chemical Activation ◽

High Surface ◽

High Surface Area ◽

Mechanistic Study ◽

Acid Mixture ◽

Maximum Adsorption Capacity ◽

Good Potential

Activated carbon was prepared from molasses, which are natural precursors of vegetable origin resulting from the sugar industry. A simple elaboration process, based on chemical activation with phosphoric acid, was proposed. The final product, prepared by activation of molasses/phosphoric acid mixture in air at 500°C, presented high surface area (more than 1400 m2/g) and important maximum adsorption capacity for methylene blue (625 mg/g) and iodine (1660 mg/g). The activated carbon (MP2(500)) showed a good potential for the adsorption of Cr(VI), Cu(II) and Pb(II) from aqueous solutions. The affinity for the three ions was observed in the following order Cu2+ Cr6+ Pb2+. The process is governed by monolayer adsorption following the Langmuir model, with a correlation coefficient close to unity.

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Producing Magnetic Nanocomposites from Paper Sludge for the Adsorptive Removal of Pharmaceuticals from Water—A Fractional Factorial Design

Nanomaterials ◽

10.3390/nano11020287 ◽

2021 ◽

Vol 11 (2) ◽

pp. 287

Author(s):

Luciana S. Rocha ◽

Érika M. L. Sousa ◽

María V. Gil ◽

João A. B. P. Oliveira ◽

Marta Otero ◽

...

Keyword(s):

Activated Carbon ◽

Factorial Design ◽

Fractional Factorial Design ◽

Metal Oxide Nanoparticles ◽

Aqueous Media ◽

Fractional Factorial ◽

Paper Sludge ◽

Synthesis Conditions ◽

Adsorptive Removal ◽

Iron Salts

In view of a simple after-use separation, the potentiality of producing magnetic activated carbon (MAC) by intercalation of ferromagnetic metal oxide nanoparticles in the framework of a powder activated carbon (PAC) produced from primary paper sludge was explored in this work. The synthesis conditions to produce cost effective and efficient MACs for the adsorptive removal of pharmaceuticals (amoxicillin, carbamazepine, and diclofenac) from aqueous media were evaluated. For this purpose, a fractional factorial design (FFD) was applied to assess the effect of the most significant variables (Fe3+ to Fe2+ salts ratio, PAC to iron salts ratio, temperature, and pH), on the following responses concerning the resulting MACs: Specific surface area (SBET), saturation magnetization (Ms), and adsorption percentage of amoxicillin, carbamazepine, and diclofenac. The statistical analysis revealed that the PAC to iron salts mass ratio was the main factor affecting the considered responses. A quadratic linear regression model A = f(SBET, Ms) was adjusted to the FFD data, allowing to differentiate four of the eighteen MACs produced. These MACs were distinguished by being easily recovered from aqueous phase using a permanent magnet (Ms of 22–27 emu g−1), and their high SBET (741–795 m2 g−1) were responsible for individual adsorption percentages ranging between 61% and 84% using small MAC doses (35 mg L−1).

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