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Activated Carbon Adsorption
Abstract
High surface area, a microporous structure, and a high degree of surface reactivity make activated carbons versatile adsorbents, particularly effective in the adsorption of organic and inorganic pollutants from aqueous solutions. Activated Carbon Adsorption introduces the parameters and mechanisms involved in the activated carbon adsorption of organic and inorganic compounds. This text brings together the most significant research on surface structure and processes, adsorption theories and isotherm equations, and applications from the latest literature on carbon adsorption. The book clearly explains the surface-related interactions of activated carbons, their energetics, and the applicability of adsorption isotherm equations and their deviation from adsorption data. It then explores numerous applications in a wide range of areas, such as nuclear technology, vacuum technology, food technology, pharmaceuticals and medicine, gas storage, oil refining, and environmental remediation. Topics include: oils and fats, molecular sieves, refining of liquid fuels, pesticides, dyes, drugs, and toxins. Three chapters are dedicated to environmental applications, including the adsorption of halogenated organic compounds and the removal of hazardous gases and vapors, organo-sulphur compounds, and other inorganic compounds from wastewater and groundwater. Activated Carbon Adsorption presents a complete survey of the growing number of state-of-the-art applications supported by a compilation of the latest perspectives in research concerning carbon surfaces and their adsorption processes from aqueous solutions. Its unified approach promotes further research towards improving and developing newer activated carbon adsorbents and processes for the efficient removal of pollutants from drinking water and industrial effluents.
... According to the different classification criteria depicted in Figure 2 and cited in References [23][24][25][26][27], they can be categorized according to the raw material used to make them, the state of appearance presentation, and the size of the stomata. Different raw materials can be divided into wooden activated carbon, shell activated carbon (coconut shell activated carbon), coal activated carbon [23], and other raw activated carbon (such as animal bone activated carbon, mineral raw activated carbon, synthetic resin activated carbon, rubber or plastic activated carbon, regenerated activated carbon, etc.). ...
... Dubinin, a scholar of the former Soviet Union, proposed that a pore diameter between 100 and 2000 nm is a large pore activated carbon; a pore diameter between 2 and 100 nm is mesoporous (also known as transition pore) activated carbon; and microporous activated carbon has a pore diameter of less than 2 nm [25]. The International Union of Theoretical and Applied Chemistry (IUPAC) lists macroporous activated carbon with a pore diameter above 50 nm, mesoporous activated carbon with a pore diameter between 2 and 50 nm, and microporous activated carbon with pore diameter below 2 nm [26]. In Different raw materials can be divided into wooden activated carbon, shell activated carbon (coconut shell activated carbon), coal activated carbon [23], and other raw activated carbon (such as animal bone activated carbon, mineral raw activated carbon, synthetic resin activated carbon, rubber or plastic activated carbon, regenerated activated carbon, etc.). ...
... Dubinin, a scholar of the former Soviet Union, proposed that a pore diameter between 100 and 2000 nm is a large pore activated carbon; a pore diameter between 2 and 100 nm is mesoporous (also known as transition pore) activated carbon; and microporous activated carbon has a pore diameter of less than 2 nm [25]. The International Union of Theoretical and Applied Chemistry (IUPAC) lists macroporous activated carbon with a pore diameter above 50 nm, mesoporous activated carbon with a pore diameter between 2 and 50 nm, and microporous activated carbon with pore diameter below 2 nm [26]. In addition to the above three classifications, activated carbon can also be classified differently according to the specific use and manufacturing process [27]. ...
SO2 and NOx emissions from iron and steel production pollute the atmosphere. With the implementation of ultra-low emission standards, the requirements for flue gas purification have become more stringent. Activated carbon, due to its rich surface chemistry, stable physical structure, and excellent adsorption and renewability, has a significant effect on the synergistic removal of multiple pollutants from industrial flue gas, and its industrial application has achieved a SO2 removal rate of ≥98% and a NOx removal rate of ≥83%. Firstly, we analyze the structure of activated carbon and the adsorption principle, discuss the mechanism of desulfurization and denitrification, and explore the shortcomings of the technology; then, we summarize the modification methods of activated carbon, determine the impregnation method of loading non-precious metal oxides as the optimal solution, and elucidate the loading conditions, process, and reaction mechanism; finally, we discuss the current status of the research, analyze the process deficiencies and the direction of optimization, and look forward to the prospect of development.
... Acid treatment in activated carbons MC and ME increased surface porosity, as reported in previous studies. [23][24][25] This treatment can remove impurities and create new pores, resulting in increased surface area and adsorption capacity. In contrast, ACQR shows a more regular surface, suggesting a lower amount of pores compared to activated carbons MC and ME. ...
... The pore volume values obtained were 0.422, 0.303 and 0.285 cm 3 /g for activated carbons MC, QR and ME, respectively. This volume represents the sum of various pore sizes, including micro-, meso-and macropores, 23 with a similar distribution among the three ACs. In all cases, the volume of mesopores (2 to 50 nm) is considerably larger than that of micro-and macropores (Figure 3), which is relevant since mesopores contribute the most to the adsorption of medium-sized molecules. ...
This study investigates the decolorization of recycled green PET bottles to enhance their recyclability and broaden their applications, particularly for high-purity and transparent materials. UV-Visible spectroscopy identified the green colorants in the PET as Solvent Green 5 (SG5), characterized by absorption regions between 400-460 nm and 580-720 nm, and Pigment Green 7 (PG7), further confirmed by X-ray photoelectron spectroscopy (XPS) which detected the presence of copper, chlorine and nitrogen. Three commercially available activated carbons (ACs) were characterized; the point of zero charge (PZC) was determined to be 2.37 for ACQR, and 7.6 and 7.98 for activated carbons MC and ME, respectively, revealing this parameter as the most influential factor in their dye adsorption capacity and selectivity. The decolorization process involved dissolving the recycled green PET, adsorbing the dyes onto the activated carbons, and separating the carbons from the PET. Colorimetric analysis of the resulting PET films showed that activated carbon content significantly impacts partial decolorization (56.15%), with ACQR preferentially adsorbing PG7, while activated carbons MC and ME primarily adsorbed SG5, demonstrably influencing the CIELAB color parameters ( L *, a *, b *). Thermal analysis indicated similar degradation behavior of the PET films between 400°C and 500°C; however, differences observed above these temperatures were attributed to variations in dye content. This approach demonstrates an effective method for PET decolorization, crucial for improving the quality and potential applications of recycled PET.
... Bands within 2924-2854 cm⁻¹ indicate aliphatic C-H stretching, while the 1267-1187cm⁻¹ region corresponds to C-O stretching from carboxylic, phenolic, or lactonic groups-functional moieties that act as active sites for adsorption. Finally, the spectral region around 655-802 cm⁻¹ is assigned to aromatic C-C stretching, reflective of the graphitic structure of activated carbon, which supports π-π interactions with organic contaminants such as dyes and printing ink residues (Bansal and Goyal, 2005;Mahmud et al., 2018;Prakash et al., 2021). Together, these spectral features confirm that the key functional groups in PAC and PFS drive coagulation through charge neutralization and floc formation, whereas the chemically diverse surface of activated carbon enables it to adsorb a wide range of organic molecules through multiple interaction mechanisms Fig. 3. ...
... Activated carbon is highly effective in water treatment, primarily due to its large surface area and porous structure, which allows it to adsorb a wide variety of contaminants, including COD, BOD 5 , TOC, TDS, and TSS. For COD (Chemical Oxygen Demand), activated carbon adsorbs organic compounds that would otherwise contribute to the demand for oxygen during oxidation processes (Bansal and Goyal, 2005). The high porosity of activated carbon enables it to trap both particulate and dissolved organic matter, significantly reducing COD levels. ...
... In such cases, the regeneration of spent PAC becomes a challenge, and it is often disposed of without reuse. In contrast, GAC, either in granulated form or pelletized form, is widely applied in gas-phase adsorption, including organic vapor recovery, indoor air purification, gas separation, respiratory protection, and vent gas purification [2]. Given the high cost of AC and the ease of regeneration [3], spent GAC used in industrial applications can be regenerated or reactivated using various methods, which will be further addressed in the subsequent section. ...
In line with the principles of the circular economy, this study aimed to develop a pyrolysis-activation regeneration process capable of producing highly porous carbon materials from spent granular activated carbon (GAC), which was generated by a high-tech electronics manufacturing company in Taiwan. Thermogravimetric analysis (TGA) and other thermochemical analyses were first conducted to investigate the thermal decomposition behavior of the spent GAC. Subsequently, the thermal regeneration system was employed to perform the N2 pyrolysis and CO2 activation experiments under various process conditions (i.e., 800, 850, and 900 °C for holding 0, 30, and 60 min, respectively). Analytical instruments included a surface area and porosimeter for pore property analysis, scanning electron microscopy (SEM) for porous texture observation, and energy dispersive X-ray spectroscopy (EDS) for surface elemental distribution analysis. The results revealed that the pore properties of thermally regenerated GAC were significantly improved compared to the spent GAC, indicating the effective removal or decomposition of adsorbed organics and deposited substances under the process conditions. Additionally, thermal regeneration via physical activation with CO2 led to enhanced pore properties compared to simple pyrolysis. The maximum BET surface area achieved exceeded 720 m²/g, which was greater than those of spent GAC (approximately 425 m²/g) and N2-pyrolyzed GAC (approximately 570 m²/g) under the same regeneration conditions (i.e., 900 °C with a 30 min holding time).
... These consist of metal ions linked by organic ligands, creating materials with great porosity and high surface area alongside exceptional adsorbent properties [134]. In this regard, pursuing new nanomaterials for capturing neonicotinoids is a goal several researchers strive for [133]. ...
Neonicotinoids are among the primary insecticides used globally, distinguished by their high efficiency against insects and low toxicity to mammals. They exhibit significant solubility and persistence in soils, making them ideal as systemic insecticides. Despite these advantages, their properties may pose risks of aquatic contamination. In recent years, the environmental impact of neonicotinoids, including pollinator populations' decline and waterways' contamination, has been assessed. Various studies have provided evidence of the risks these compounds present at the environmental level, prompting actions that have generated new research areas focused on reducing the concentration of these insecticides in the environment. Several methodologies have been proposed to remove neonicotinoids from water samples, including nanomaterials, which have shown promising results and efficiency in adsorbing pollutants of this type. This review presents information on some methods for removing neonicotinoids. Firstly, it will provide an overview of neonicotinoid insecticides, highlighting their importance in the pesticide industry. Secondly, it will discuss proposed methodologies for the removal of these insecticides. Finally, it will emphasize recent developments in emerging materials designed for this purpose, based on experimental and theoretical approaches.
Layered Double Hydroxides (LDHs), particularly Ni/Fe-Layered Double Hydroxides (Ni/Fe-LDHs), have attracted significant attention as adsorbents for environmental waste removal. This study investigates the desalination effectiveness of Ni/Fe-LDHs in removing sodium salts via ion exchange and their ability to adsorb ciprofloxacin (Cipro) contaminants from wastewater. Batch adsorption tests were conducted to evaluate the removal of salts and pollutants under varying pH, Ni/Fe-LDH dose, contact time, and pollutant concentration. Characterization of Ni/Fe-LDHs was performed using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, high resolution transmission electron microscopy (HRTEM), pH of zero gcharge (pHPZC), and Brunauer–Emmett–Teller (BET) surface area measurements. The results showed that the removal efficiency of Cipro was highest at pH 5.0, with a Ni/Fe-LDH dose of 0.05 g achieving 40.14% removal within 0–300 min. In the desalination process, the material achieved a dosage of 0.05 g, a solution concentration range of 1000–16,000 ppm, and an impressive ion removal rate of approximately 99.8%. After six cycles, regeneration or replacement of the ion-removal material may be necessary to maintain efficient desalination. Adsorption data were modeled using Langmuir, Freundlich, and Khan isotherms, demonstrating surface heterogeneity and high adsorption capacity. The prepared material demonstrated excellent re-usability, maintaining high removal efficiencies over five regeneration cycles also exhibited significant antimicrobial activity against Proteus mirabilis , Salmonella Typhimurium , Escherichia coli , Pseudomonas aeruginosa , and Klebsiella pneumoniae , with notable minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and inhibition zone values. This suggests the potential of Ni/Fe-LDHs as effective tools for bioremediation in pharmaceutical and wastewater treatment industries. The cost of using Ni/Fe-LDH was estimated at 2.02 USD/g.
Graphical abstract
Recently, adsorption by nanomaterials and reverse osmosis has become the leading technologies for heavy metal removal. In a comparative study on Cu2+ removal efficiency, carboxyl multiwalled carbon nanotubes and RO membrane filtration were considered in terms of their efficiency. Fourier Transform Infrared (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), Brunauer–Emmett–Teller (BET), and X-Ray Diffraction (XRD) were employed for nanotube characterization. In the adsorption processes, the effects of such parameters as contact time, adsorbent dosage, pH of the solution, and initial concentration of Cu2+ on the efficiency of adsorption were assessed. The Cu2+ removal efficiency was 99.24% under optimum conditions, featuring a contact time of 120 min, pH of 9.5, adsorbent dosage of 50 mg, and an initial concentration of Cu2+ of 75 mg/L. Furthermore, the adsorption was matched by both Freundlich isotherm and the pseudo-second-order kinetic model. In the RO process, the transmembrane pressure, feed pH, and initial Cu2+ concentration influenced efficiency. The results show that, according to operating conditions, Cu2+ retention rates fluctuate between 97.11% and 99.33% in RO processes.
Activated carbons were obtained from three types of raw materials from the canning industry: peach, plum, and olive stones. The chemical composition and texture of the precursors and the physicochemical properties of the obtained carbons were analyzed. It was found that under the same conditions of preparation, the properties of the raw materials significantly affect the parameters of the activated carbons. The obtained carbons were oxidized with 12% nitric acid to form a larger amount of acidic oxygen-containing groups on their surface. The porous texture, the size, and the chemical nature of the surface of the activated carbons were analyzed. The adsorption capacity of the obtained activated carbons towards chlorhexidine gluconate contained in mouthwash was determined. It was found that the three carbons have a significant adsorption capacity towards chlorhexidine gluconate: 189.1 mg/g for carbon from peach stones, 189.1 mg/g for carbon from plum stones, and 156.7 mg/g for carbon from olive stones, respectively. It has been determined that the adsorption of chlorhexidine gluconate on the surface of the obtained activated carbons obeys the Langmuir model. It has been established that the adsorption capacity of the obtained activated carbons is influenced by their porous texture, size, and chemical nature of the surface.
The addition of graphene to metal oxides creates a hybrid material with enhanced physicochemical properties, of interest in a range of applications and technologies. For example, graphene combined with narrow band gap metal oxides holds considerable promise in solar energy. This book presents the methods used to characterise and understand their properties. Chapters from international authors present tailored synthetic approaches to producing materials for applications such as environmental remediation, photocatalysis, sensors, and light-emitting diodes.
With a contemporary outlook on this emerging and popular class of material, this book combines ongoing research with practical techniques and real-world examples to provide an all-encompassing resource in the field and inspire future developments in academia and industry.
The removal efficiency of activated carbon Filtrasorb 400 (F-400) towards three highly used reactive dyes in the textile industry was investigated. In this work, the adsorption capacities for the anionic reactive dyes, namely; Remazol Reactive Yellow, Remazol Reactive Black and Remazol Reactive Red were determined. The adsorption capacity data showed a high removal ability for the three reactive dyes and a distinguished ability for R. Yellow. The high adsorption capacities for F-400 were attributed to the net positive surface charge during the adsorption process. Surface acidity, surface basicity, H+ and OH− adsorption capacities and pHZPC for F-400 were estimated and compared with other reported values.
A description of an experiment that illustrates an interesting biomedical application of adsorption from solution and demonstrates some of the factors that influence the in vivo adsorption of drug molecules onto activated carbon. Keywords (Audience): Upper-Division Undergraduate