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21 pages, 3752 KiB

Open AccessArticle

The Adsorption of Chlorpromazine on the Surface of Gold Nanoparticles and Its Effect on the Toxicity to Selected Mammalian Cells

by Magdalena Oćwieja, Anna Barbasz, Oliwia Kowalska, Julia Maciejewska-Prończuk and Agata Lada

Materials 2024, 17(19), 4774; https://doi.org/10.3390/ma17194774 - 28 Sep 2024

Viewed by 697

Abstract

Chlorpromazine (CPZ) is a first-generation neuroleptic with well-established antitumor and antiviral properties. Currently, numerous studies are focused on developing new methods for CPZ delivery; however, the knowledge regarding its conjugates with metal nanoparticles remains limited. The aim of this study was to prepare [...] Read more.

Chlorpromazine (CPZ) is a first-generation neuroleptic with well-established antitumor and antiviral properties. Currently, numerous studies are focused on developing new methods for CPZ delivery; however, the knowledge regarding its conjugates with metal nanoparticles remains limited. The aim of this study was to prepare CPZ conjugates with gold nanoparticles (AuNPs) and evaluate their biological activity on human lymphocytes (HUT-78 and COLO 720L), as well as human (COLO 679) and murine (B16-F0) melanoma cells, in comparison to the effects induced by unconjugated CPZ molecules and AuNPs with well-defined properties. During the treatment of cells with CPZ, AuNPs, and CPZ-AuNP conjugates, changes in mitochondrial activity, membrane integrity, and the secretion of lipid peroxidation mediators were studied using standard biological assays such as MTT, LDH, and MDA assays. It was found that positively charged CPZ-AuNP conjugates more effectively reduced cell viability compared to AuNPs alone. The dose-dependent membrane damage was correlated with oxidative stress resulting from exposure to CPZ-AuNP conjugates. The activity of the conjugates depended on their composition and the size of the AuNPs. It was concluded that conjugating CPZ to AuNPs reduced its biological activity, while the cellular response to the treatment varied depending on the specific cell type. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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17 pages, 8769 KiB

Open AccessArticle

Assessment of Physico-Chemical Behavior and Sorptivity—Diatomaceous Earth as Support for Paraffinic Phase-Change Materials

by Agnieszka Przybek

Materials 2024, 17(19), 4691; https://doi.org/10.3390/ma17194691 - 24 Sep 2024

Viewed by 677

Abstract

Diatomite’s most common application is its use as a sorbent for petroleum substances. Since paraffin is a petroleum derivative, this paper investigates the sorption capacity of diatomite to absorb it. In this paper, the physical and chemical properties were studied for 4 different [...] Read more.

Diatomite’s most common application is its use as a sorbent for petroleum substances. Since paraffin is a petroleum derivative, this paper investigates the sorption capacity of diatomite to absorb it. In this paper, the physical and chemical properties were studied for 4 different fractions of diatomite (0–0.063 mm; 0–2 mm; 0.5–3 mm; and 2–5 mm) in the crude and calcined states, and the sorption capacity of diatomite earth for absorbing paraffinic phase-change substances was determined. The physical and chemical studies of the material included conducting an oxide chemical composition analysis using XRF, examining the composition of the mineral phases using X-ray diffraction, and determining the particle size, porosity, and thermal conductivity of the diatomite. Morphology images were also taken for all 8 diatomite variants using scanning electron microscopy. Each fraction was subjected to static calcination at 850 °C for 24 h. The results showed that the calcination of the diatomite increased the porosity of the material and reduced the thermal conductivity coefficient, and most importantly, the sorption capacity to absorb paraffins. The highest sorption capacity was characterized by calcined diatomite powder, that is, diatomite with the smallest particle size. Absorption of paraffinic substances by diatomite exceeding 200 wt.% is possible. Thus, diatomite is one of the feasible candidates for an economical and lightweight building material for making PCM composites for thermal energy storage in buildings. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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17 pages, 9318 KiB

Open AccessArticle

Impact of Mechanochemical Activation (MChA) on Characteristics and Dye Adsorption Behavior of Sawdust-Based Biocarbons

by Barbara Wawrzaszek, Barbara Charmas, Katarzyna Jedynak and Ewa Skwarek

Materials 2024, 17(18), 4458; https://doi.org/10.3390/ma17184458 - 11 Sep 2024

Viewed by 557

Abstract

The increase in environmental pollution due to the development of industry and human activity has resulted in intensive development of research on the possibility of its purification. A very effective method is the pollutants’ adsorption from the air and water environment. For adsorption [...] Read more.

The increase in environmental pollution due to the development of industry and human activity has resulted in intensive development of research on the possibility of its purification. A very effective method is the pollutants’ adsorption from the air and water environment. For adsorption to be effective, materials with a specific structure and a well-developed surface decorated with numerous functionalities, e.g., biocarbons (BC), are necessary. An effective method of activating biocarbons is mechanochemical milling, an environmentally friendly procedure. This paper describes the possibility of using mechanochemical activation (MChA) of non-porous biocarbons to develop surface and porosity for their use in processes of pollutant adsorption. BC was characterized based on N₂ adsorption, thermogravimetry (TGA), SEM/EDS imaging, Fourier (ATR-FTIR) and Raman spectroscopies, as well as titration using the Boehm method and determination of zeta potential. The adsorption capacity of BC for methylene blue (MB) was studied. It was proven that the solvent-free MChA made it possible to obtain microporous biocarbons, causing an intensive increase in the surface area and pore volume and the generation of oxygen functionalities. The biocarbons had predominantly acidic (mainly carboxylic) or basic functionalities and exhibited an amorphous structure. BC proved to be effective in adsorbing MB from aqueous solutions. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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24 pages, 7478 KiB

Open AccessArticle

Adsorption of Selected Herbicides on Activated Carbon from Single- and Multi-Component Systems—Error Analysis in Isotherm Measurements

by Magdalena Blachnio, Malgorzata Zienkiewicz-Strzalka and Anna Derylo-Marczewska

Materials 2024, 17(17), 4232; https://doi.org/10.3390/ma17174232 - 27 Aug 2024

Viewed by 538

Abstract

The aim of this study is to examine the influence of various factors on the precision and repeatability of the experimental determination of herbicide adsorption isotherms. Studies were conducted for the activated carbon RIB as an adsorbent and three herbicides as adsorbates: 2,4-dichlorophenoxyacetic [...] Read more.

The aim of this study is to examine the influence of various factors on the precision and repeatability of the experimental determination of herbicide adsorption isotherms. Studies were conducted for the activated carbon RIB as an adsorbent and three herbicides as adsorbates: 2,4-dichlorophenoxyacetic acid (2,4-D), 4-chlorophenoxyacetic acid (4-CPA), and 3-chlorophenoxypropionic acid (3-CPP). The herbicide adsorption process was carried out in single-component and multi-component modes (the herbicide was adsorbed in the presence of an accompanying substance, i.e., 4-nitroaniline (4-NA)). Due to the significant contribution of the competition phenomenon in the adsorption process, which is important, e.g., in multi-component environmental systems, a qualitative and quantitative analysis of herbicide adsorption in the presence of a competing substance was presented. This work presents, among other things, the influence of adsorbent heterogeneity (grain size) on measurement uncertainties. The spread of standard deviations for solutions requiring dilution during spectrophotometric measurements was discussed, indicating that dilutions contribute to increasing measurement uncertainties. The heterogeneity parameters of the Freundlich equation for the studied adsorption systems were analyzed; the 2,4-D/RIB system was indicated as the most energetically heterogeneous. Differentiation of the experimental conditions (pH, temperature) allowed us to assess their impact on the efficiency and mechanism of adsorption. A high repeatability of experimental isotherms was obtained for the multi-component system. The accuracy of quantitative determination of equilibrium concentrations for the tested two-component systems was assessed based on the measured UV-Vis spectra, and the adsorption of herbicides from single- and multi-component systems was compared. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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20 pages, 3091 KiB

Open AccessArticle

Using Zeolite Materials to Remove Pharmaceuticals from Water

by Tomasz Bajda, Agnieszka Grela, Justyna Pamuła, Joanna Kuc, Agnieszka Klimek, Jakub Matusik, Wojciech Franus, Santhana Krishna Kumar Alagarsamy, Tomasz Danek and Paweł Gara

Materials 2024, 17(15), 3848; https://doi.org/10.3390/ma17153848 - 3 Aug 2024

Cited by 2 | Viewed by 930

Abstract

Pharmaceutical drugs, including antibiotics and hormonal agents, pose a significant threat to environmental and public health due to their persistent presence in aquatic environments. Colistin (KOL), fluoxetine (FLUO), amoxicillin (AMO), and 17-alpha-ethinylestradiol (EST) are pharmaceuticals (PhCs) that frequently exceed regulatory limits in water [...] Read more.

Pharmaceutical drugs, including antibiotics and hormonal agents, pose a significant threat to environmental and public health due to their persistent presence in aquatic environments. Colistin (KOL), fluoxetine (FLUO), amoxicillin (AMO), and 17-alpha-ethinylestradiol (EST) are pharmaceuticals (PhCs) that frequently exceed regulatory limits in water and wastewater. Current removal methods are mainly ineffective, necessitating the development of more efficient techniques. This study investigates the use of synthetic zeolite (NaP1_FA) and zeolite-carbon composites (NaP1_C), both derived from fly ash (FA), for the removal of KOL, FLUO, AMO, and EST from aquatic environments. Batch adsorption experiments assessed the effects of contact time, adsorbent dosage, initial concentration, and pH on the removal efficiency of the pharmaceuticals. The results demonstrated that NaP1_FA and NaP1_C exhibited high removal efficiencies for all tested pharmaceuticals, achieving over 90% removal within 2 min of contact time. The Behnajady-Modirshahla-Ghanbary (BMG) kinetic model best described the adsorption processes. The most effective sorption was observed with a sorbent dose of 1–2 g L⁻¹. Regarding removal efficiency, the substances ranked in this order: EST was the highest, followed by AMO, KOL, and FLUO. Sorption efficiency was influenced by the initial pH of the solutions, with optimal performance observed at pH 2–2.5 for KOL and FLUO. The zeolite-carbon composite NaP1_C, due to its hydrophobic nature, showed superior sorption efficiency for hydrophobic pharmaceuticals like FLUO and EST. The spectral analysis reveals that the primary mechanism for immobilizing the tested PhCs on zeolite sorbents is mainly due to physical sorption. This study underscores the potential of utilizing inexpensive, fly ash-derived zeolites and zeolite-carbon composites to remove pharmaceuticals from water effectively. These findings contribute to developing advanced materials for decentralized wastewater treatment systems, directly addressing pollution sources in various facilities. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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12 pages, 1529 KiB

Open AccessArticle

From Waste to Water Purification: Textile-Derived Sorbents for Pharmaceutical Removal

by Magdalena Mazur, Kamyar Shirvanimoghaddam, Moon Paul, Minoo Naebe, Tomasz Klepka, Artur Sokołowski and Bożena Czech

Materials 2024, 17(15), 3684; https://doi.org/10.3390/ma17153684 - 25 Jul 2024

Viewed by 690

Abstract

The presence of pharmaceuticals or their active metabolites in receiving waters is a sign of the inefficient removal of bioactive substrates from wastewater. Adsorption seems to be the most effective and inexpensive method of their removal. Waste management aimed at sorbents is a [...] Read more.

The presence of pharmaceuticals or their active metabolites in receiving waters is a sign of the inefficient removal of bioactive substrates from wastewater. Adsorption seems to be the most effective and inexpensive method of their removal. Waste management aimed at sorbents is a promising way to sustain several sustainable development goals. In the presented paper, the removal of the two most widely used drugs in the wastewater was examined. Diclofenac and carbamazepine were removed from water and wastewater using textile waste-derived sorbents. Their removal efficiency was verified by testing several process parameters such as the time of the sorption, the presence of interfering inorganic ions, the presence of dissolved organic matter, the initial pH and ionic strength of the solution, and various water matrices. The adsorption capacity was noted for diclofenac (57.1 mg/g) and carbamazepine (21.25 mg/g). The tested process parameters (pH, presence of inorganic ions, dissolved organic matter, ionic strength, water matrix) confirmed that the presented waste materials possessed a great potential for pharmaceutical removal from water matrices. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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20 pages, 5535 KiB

Open AccessArticle

Radioactive Attenuation Using Different Types of Natural Rocks

by S. A. Abd El-Azeem and Nareman M. Harpy

Materials 2024, 17(14), 3462; https://doi.org/10.3390/ma17143462 - 12 Jul 2024

Viewed by 703

Abstract

Humans benefit from nuclear technology, but it also generates nuclear radiation that is bad for both the environment and human health. The serious issue of radiation leakage affects many technological applications. Shielding is required to protect both users and the environment from negative [...] Read more.

Humans benefit from nuclear technology, but it also generates nuclear radiation that is bad for both the environment and human health. The serious issue of radiation leakage affects many technological applications. Shielding is required to protect both users and the environment from negative side effects. This work describes the radioactive attenuation properties of some natural rocks, such as claystone, bentonitic claystone, bentonitic shale, sandstone, and basalt using a NaI(Tl) detector. The mass attenuation coefficients

μ_{m}

of these rocks at various photon energies, half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP) were determined. The validation of obtained values of

μ_{m}

was carried out against the theoretical calculations from the XCOM program, and the correlation factor and relative deviation between the two methods were evaluated. It was noted that basalt samples exhibit superior shielding parameters when compared to other rock samples. Also, the concentrations of naturally occurring radioactive elements (²³⁸U, ²²⁶Ra, ²³²Th, and ⁴⁰K) were measured, allowing for the calculation of environmental hazard indices and assessment of attenuation (%) efficiency for certain natural rocks, such as bentonite, sandstone, and basalt. The results revealed that increasing the thickness of Basalt-AZ from 1.5 cm to 2 cm results in an approximate 11% rise in attenuation percentage, with values reaching 77.12%, 67.2%, 67.65%, and 59.8% for NMA-U, IAEA-Th, IAEA-Ra, and IAEA-K, respectively. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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12 pages, 2430 KiB

Open AccessArticle

Evaluation of Ammonium Nitrate(V) Morphology and Porosity Obtained by SEM and Tomography Imaging

by Andrzej Biessikirski, Grzegorz Piotr Kaczmarczyk, Łukasz Kuterasiński, Malwina Kolano and Mateusz Pytlik

Materials 2024, 17(13), 3156; https://doi.org/10.3390/ma17133156 - 27 Jun 2024

Cited by 1 | Viewed by 802

Abstract

This paper presents an evaluation of the morphology of fertilizer-grade and prill-grade ammonium nitrate(V). All samples were analyzed using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and tomography techniques. The XRD results revealed that despite various provenances, all samples exhibited similar P [...] Read more.

This paper presents an evaluation of the morphology of fertilizer-grade and prill-grade ammonium nitrate(V). All samples were analyzed using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and tomography techniques. The XRD results revealed that despite various provenances, all samples exhibited similar P_mmm symmetry and diffraction patterns. SEM images indicated that prill ammonium nitrate(V) showed a more complex external and internal crystal structure than fertilizer-grade counterparts. Furthermore, tomography analysis revealed that each prill ammonium nitrate(V) sample demonstrated distinct porosity characteristics, including varying pore sizes and distribution patterns. Both methods confirmed that fertilizer-grade ammonium nitrate(V) in the cross-section had a pumice structure, and porous prill ammonium nitrate(V) had a rather complex structure, with a central cavity observed only in the case of Sample 4. The appearance of a central cavity can be explained by the different conditions or manufacturing processes of porous prill ammonium nitrate(V). Moreover, the fertilizer-type ammonium nitrate(V) exhibited the lowest surface-to-volume ratio of ca. 21% compared to the porous-type ammonium nitrate(V). This, together with the lowest surface area of ca. 116 mm², confirmed the lowest absorption capacity of the fertilizer-grade ammonium nitrate(V) disclosed by the ammonium nitrate(V) producer. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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10 pages, 659 KiB

Open AccessArticle

Numerical Analysis of the Porous Structure of Activated Carbons Derived from Synthetic Polymers

by Mirosław Kwiatkowski, Isabel Pestana da Paixão Cansado and Paulo Mira Mourão

Materials 2024, 17(13), 3122; https://doi.org/10.3390/ma17133122 - 26 Jun 2024

Viewed by 1199

Abstract

This paper presents original results from the unique analysis of the porous structure of activated carbons (ACs) produced through the chemical activation of polyethylene terephthalate (PET) and polyacrylonitrile (PAN), as well as from a physical mixture of both polymers. An advanced method of [...] Read more.

This paper presents original results from the unique analysis of the porous structure of activated carbons (ACs) produced through the chemical activation of polyethylene terephthalate (PET) and polyacrylonitrile (PAN), as well as from a physical mixture of both polymers. An advanced method of adsorbent surface analysis—more specifically, the new method of numerical clustering-based adsorption analysis regarding the surface heterogeneity, pore geometry and adsorption energy distribution parameters—allowed us to obtain information about the porous structure of the ACs from the synthetic polymers mentioned above. As the results showed, ACs obtained with PAN were characterised by a first adsorbed layer with the highest volume. When the surface heterogeneity, highly desirable in most advanced adsorption processes, is taken into account, the materials with the best surface properties in both potassium carbonate (K₂CO₃) and potassium hydroxide (KOH) activation processes were the ACs obtained with a mass proportion of PET to PAN of 1:3, which were characterised by a low degree of surface heterogeneity and a first adsorbed layer presenting a relatively large volume. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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18 pages, 5823 KiB

Open AccessArticle

Modified Ordered Mesoporous Carbons for Cr(VI) Removal from Wastewater

by Rafał Olchowski, Kinga Morlo, Agnieszka Chałabis-Mazurek, Ryszard Dobrowolski and Katarzyna Tyszczuk-Rotko

Materials 2024, 17(12), 2881; https://doi.org/10.3390/ma17122881 - 13 Jun 2024

Viewed by 611

Abstract

The pristine CMK-3 carbon was ozonized and then chemically modified by the Zr and Fe compounds. The synthesized carbonaceous materials were characterized with physicochemical methods. The obtained carbons had a high specific surface area (ca. 800 m² g⁻¹) and an [...] Read more.

The pristine CMK-3 carbon was ozonized and then chemically modified by the Zr and Fe compounds. The synthesized carbonaceous materials were characterized with physicochemical methods. The obtained carbons had a high specific surface area (ca. 800 m² g⁻¹) and an acidic surface. The Cr(VI) adsorption properties of the oxidized and Zr/Fe-modified carbon were studied. The highest static adsorption capacity towards Cr(VI) ions was evaluated for Zr/Fe-modified carbon (50.1 mg g⁻¹) at pH_eq = 5.8 after 240 min. The Elovich and Freundlich theoretical models were well fitted to the Cr(VI) adsorption kinetic and isotherm data on the Zr/Fe-modified CMK-3-type carbon. The leading Cr(VI) adsorption mechanism acting on the Zr/Fe-modified carbon was probably based on the redox reactions between Cr(VI) and the carbonaceous surface. Electrostatic attraction and surface complexation processes could also occur during Cr(VI) adsorption in the studied system. The effect of the competitive anions on the concentration level, such as in the galvanic wastewater for Cr(VI) adsorption onto chemically modified carbon, was negligible. The HCl and HNO₃ media were insufficient for the Zr/Fe-modified carbon regeneration after Cr(VI) adsorption. The Zr/Fe-modified carbon was successfully applied for the efficient (>90%) Cr(VI) removal from the model galvanic wastewater. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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12 pages, 3520 KiB

Open AccessArticle

Comparative Study for Propranolol Adsorption on the Biochars from Different Agricultural Solid Wastes

by Wenjie Nie, Qianqian Che, Danni Chen, Hongyu Cao and Yuehua Deng

Materials 2024, 17(12), 2793; https://doi.org/10.3390/ma17122793 - 7 Jun 2024

Viewed by 607

Abstract

Currently, large amounts of agricultural solid wastes have caused serious environmental problems. Agricultural solid waste is made into biochar by pyrolysis, which is an effective means of its disposal. As the prepared biochar has a good adsorption capacity, it is often used to [...] Read more.

Currently, large amounts of agricultural solid wastes have caused serious environmental problems. Agricultural solid waste is made into biochar by pyrolysis, which is an effective means of its disposal. As the prepared biochar has a good adsorption capacity, it is often used to treat pollutants in water, such as heavy metals and pharmaceuticals. PRO is an emerging contaminant in the environment today. However, there are limited studies on the interaction between biochars with PRO. Thus, in this study, we investigate the adsorption of PRO onto the biochars derived from three different feedstocks. The order of adsorption capacity was corn stalk biochar (CS, 10.97 mg/g) > apple wood biochar (AW, 10.09 mg/g) > rice husk biochar (RH, 8.78 mg/g). When 2 < pH < 9, the adsorption capacity of all the biochars increased as the pH increased, while the adsorption decreased when pH > 9, 10 and 10.33 for AW, CS and RH, respectively. The adsorption of PRO on biochars was reduced with increasing Na⁺ and Ca²⁺ concentrations from 0 to 200 mg·L⁻¹. The effects of pH and coexisting ions illustrated that there exist electrostatic interaction and cation exchange in the process. In addition, when HA concentration was less than 20 mg/L, it promoted the adsorption of PRO on the biochars; however, when the concentration was more than 20 mg/L, its promoting effect was weakened and gradually changed into an inhibitory effect. The adsorption isotherm data of PRO by biochars were best fitted with the Freundlich model, indicating that the adsorption process is heterogeneous adsorption. The adsorption kinetics were fitted well with the pseudo-second-order model. All the results can provide new information into the adsorption behavior of PRO and the biochars in the aquatic environment and a theoretical basis for the large-scale application of biochar from agricultural solid wastes. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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14 pages, 4266 KiB

Open AccessArticle

Crosslinked Polydiallyldimethylammonium Chloride Adsorbent for the Selective Separation of Rhenium Ions from Pregnant Leach Solutions

by Mohammadbagher Fathi, Mehdi Mahmoudian, Richard Diaz Alorro and Mostafa Chegini

Materials 2024, 17(11), 2737; https://doi.org/10.3390/ma17112737 - 4 Jun 2024

Viewed by 850

Abstract

The depletion of valuable mineral reserves has rendered effluents generated from mining and industrial processing activities a promising resource for the production of precious elements. The synthesis and improvement of new adsorbents to extract valuable compounds from industrial wastes and pregnant leach solutions, [...] Read more.

The depletion of valuable mineral reserves has rendered effluents generated from mining and industrial processing activities a promising resource for the production of precious elements. The synthesis and improvement of new adsorbents to extract valuable compounds from industrial wastes and pregnant leach solutions, besides increasing wealth, can play a significant role in reducing environmental concerns. In this work, a new and low-cost adsorbent for the selective extraction of rhenium (perrhenate ions, ReO₄⁻) was synthesized by the free-radical polymerization (FRP) of a diallyl dimethylammonium chloride monomer (quaternary amine) in the presence of a crosslinker. Various methods were employed to characterize the polymeric adsorbent. The results revealed that the designed polymeric adsorbent had a high surface area and pores with nano-metric dimensions and a pore volume of 6.4 × 10⁻³ cm³/g. Four environments—single, binary, multicomponent, and real solutions—were applied to evaluate the adsorbent’s performance in the selective separation of Re. Additionally, these environments were used to understand the behavior of molybdenum ions, the primary competitors of perrhenate ions in the ion exchange process. In competitive conditions, using variations in q_e_,mix/q_e, an antagonism phenomenon (q_e_,mix/q_e < 1) occurred due to the inhibitory effect of surface-adsorbed molybdenum ions on the binding of the perrhenate ions. However, across all conditions, the separation values for Re were higher than those for the other studied elements (Mo, Cu, Fe). Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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16 pages, 5734 KiB

Open AccessArticle

Facile Fabrication of Porous Adsorbent with Multiple Amine Groups for Efficient and Selective Removal of Amaranth and Tartrazine Dyes from Water

by Qingli Chen, Jie Liao, Sihua Zeng and Li Zhou

Materials 2024, 17(10), 2391; https://doi.org/10.3390/ma17102391 - 16 May 2024

Cited by 2 | Viewed by 878

Abstract

The development of an advanced dye adsorbent that possesses a range of beneficial characteristics, such as high adsorption capacity, swift adsorption kinetics, selective adsorption capability, and robust reusability, remains a challenge. This study introduces a facile method for fabricating an amine-rich porous adsorbent [...] Read more.

The development of an advanced dye adsorbent that possesses a range of beneficial characteristics, such as high adsorption capacity, swift adsorption kinetics, selective adsorption capability, and robust reusability, remains a challenge. This study introduces a facile method for fabricating an amine-rich porous adsorbent (ARPA), which is specifically engineered for the adsorptive removal of anionic dyes from aqueous solutions. Through a comprehensive assessment, we have evaluated the adsorption performance of ARPA using two benchmark dyes: amaranth (ART) and tartrazine (TTZ). Our findings indicate that the adsorption process reaches equilibrium in a remarkably short timeframe of just 20 min, and it exhibits an excellent correlation with both the Langmuir isotherm model and the pseudo-second-order kinetic model. Furthermore, ARPA has demonstrated an exceptional maximum adsorption capacity, with values of 675.68 mg g⁻¹ for ART and 534.76 mg g⁻¹ for TTZ. In addition to its high adsorption capacity, ARPA has also shown remarkable selectivity, as evidenced by its ability to selectively adsorb TTZ from a mixed dye solution, a feature that is highly desirable for practical applications. Beyond its impressive adsorption capabilities, ARPA can be efficiently regenerated and recycled. It maintains a high level of original removal efficiency for both ART (76.8%) and TTZ (78.9%) even after five consecutive cycles of adsorption and desorption. Considering the simplicity of its synthesis and its outstanding adsorption performance, ARPA emerges as a highly promising material for use in dye removal applications. Consequently, this paper presents a straightforward and feasible method for the production of an effective dye adsorbent for environmental remediation. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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14 pages, 8343 KiB

Open AccessArticle

Iron–Carbon Nanospheres as Promising Material for Magnetic Assisted Adsorption and Separation of Impurities from a Liquid Phase

by Iwona Pełech, Sabina Lewinska, Monika Arciszewska, Abdul Khaliq, Anna Ślawska-Waniewska, Daniel Sibera, Piotr Staciwa and Urszula Narkiewicz

Materials 2024, 17(9), 2111; https://doi.org/10.3390/ma17092111 - 29 Apr 2024

Cited by 1 | Viewed by 881

Abstract

The composites containing various iron compounds and highly microporous carbon spheres were produced and investigated for structural and magnetic properties. Iron citrate, nitrate and chloride were used to prepare samples and the obtained products contained iron, iron carbide or magnetite. All the produced [...] Read more.

The composites containing various iron compounds and highly microporous carbon spheres were produced and investigated for structural and magnetic properties. Iron citrate, nitrate and chloride were used to prepare samples and the obtained products contained iron, iron carbide or magnetite. All the produced samples were characterized by high porosity and good magnetic properties. The coupling of the high porosity of carbon spheres with magnetic properties of iron compounds provides a potential application of the composites to removal of impurities from water, followed by a magnetic separation of the sorbent. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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21 pages, 3918 KiB

Open AccessArticle

Removal of Organic Dyes, Polymers and Surfactants Using Carbonaceous Materials Derived from Walnut Shells

by Małgorzata Wiśniewska, Teresa Urban, Karina Tokarska, Paulina Marciniak, Anna Giel and Piotr Nowicki

Materials 2024, 17(9), 1987; https://doi.org/10.3390/ma17091987 - 25 Apr 2024

Cited by 1 | Viewed by 819

Abstract

A series of new granular carbonaceous adsorbents was prepared via single-stage physical and chemical activation of walnut shells. Their suitability for removing various types of organic pollutants (represented by dyes, surfactants and water-soluble polymers) from the liquid phase was assessed. The activation of [...] Read more.

A series of new granular carbonaceous adsorbents was prepared via single-stage physical and chemical activation of walnut shells. Their suitability for removing various types of organic pollutants (represented by dyes, surfactants and water-soluble polymers) from the liquid phase was assessed. The activation of the precursor was carried out with CO₂ and H₃PO₄ using conventional heating. Activated biocarbons were characterized in terms of chemical composition, acidic–basic nature of the surface, textural and electrokinetic properties as well as thermal stability. Depending on the type of activating agent used during the activation procedure, the obtained biocarbons differed in terms of specific surface area (from 401 to 1361 m²/g) and the type of porous structure produced (microporosity contribution in the range of 45–75%). Adsorption tests proved that the effectiveness of removing organic pollutants from the liquid phase depended to a large extent on the type of prepared adsorbent as well as the chemical nature and the molecular size of the adsorbate used. The chemically activated sample showed greater removal efficiency in relation to all tested pollutants. Its maximum adsorption capacity for methylene blue, poly(acrylic acid), poly(ethylene glycol) and Triton X-100 reached the levels of 247.1, 680.9, 38.5 and 61.8 mg/g, respectively. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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17 pages, 3536 KiB

Open AccessArticle

Adsorption of Co²⁺ and Cr³⁺ in Industrial Wastewater by Magnesium Silicate Nanomaterials

by Jing Bao, Yongjun Feng, Yong Pan and Juncheng Jiang

Materials 2024, 17(9), 1946; https://doi.org/10.3390/ma17091946 - 23 Apr 2024

Cited by 2 | Viewed by 928

Abstract

In this paper, two flower-like magnesium silicate nanomaterials were prepared. These and another two commercial magnesium silicate materials were characterized using a scanning electron microscope, the N₂ adsorption–desorption method, and other methods. The structure–activity relationship between the adsorption performance of these four [...] Read more.

In this paper, two flower-like magnesium silicate nanomaterials were prepared. These and another two commercial magnesium silicate materials were characterized using a scanning electron microscope, the N₂ adsorption–desorption method, and other methods. The structure–activity relationship between the adsorption performance of these four magnesium silicate materials and their specific surface area, pore size distribution, and pore structure was compared. The results showed that the 3-FMS modified by sodium dodecyl sulfonate (SDS) had the largest specific surface area and pore size, the best adsorption performance, and the largest experimental equilibrium adsorption capacity (q_e,exp) for Co²⁺, reaching 190.01 mg/g, and Cr³⁺, reaching 208.89 mg/g. The adsorption behavior of the four materials for Co²⁺ and Cr³⁺ both fitted the pseudo-second-order kinetic model and Langmuir adsorption model, indicating that chemical monolayer uniform adsorption was the dominant adsorption process. Among them, the theoretical adsorption capacity (q_m) of 3-FMS was the highest, reaching 207.62 mg/g for Co²⁺ and 230.85 mg/g for Cr³⁺. Through further research, it was found that the four materials mainly removed Co²⁺ and Cr³⁺ through electrostatic adsorption, surface metal ions (Mg²⁺), and acidic groups (-OH and -SO₃H) exchanging with ions in solution. The adsorption performance of two self-made flower-like magnesium silicate materials for Co²⁺ and Cr³⁺ was superior to that of two commercial magnesium silicates. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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19 pages, 2042 KiB

Open AccessArticle

Manufacturing Options for Activated Carbons with Selected Synthetic Polymers as Binders

by Iwona Skoczko, Ewa Szatyłowicz, Adam Tabor and Remigiusz Gumiński

Materials 2024, 17(8), 1753; https://doi.org/10.3390/ma17081753 - 11 Apr 2024

Cited by 1 | Viewed by 1016

Abstract

Formed activated carbon (AC) is a multipurpose product with developed adsorption properties that is widely used in various areas of life. To create AC, hard coal has to go through various processes: grinding, granulation, carbonization, physical and/or chemical activation. Presented research was conducted [...] Read more.

Formed activated carbon (AC) is a multipurpose product with developed adsorption properties that is widely used in various areas of life. To create AC, hard coal has to go through various processes: grinding, granulation, carbonization, physical and/or chemical activation. Presented research was conducted in the professional company manufacturing activated carbons. Studied AC reached the demanded shape of grains thanks to binders added to granulation process. Research on the AC formed using new polymeric binders (applied so far in other branches: pharmacy and construction materials) is presented in this manuscript. Tested binders were not used before to manufacture ACs in the professional technological line. Such polymers as: sodium carboxymethylhydrocellulose (CMHC), poly[1-(2-oxo-1-pyrrolidinyl)ethylene] (POPE) and enriched methyl-hydroxypropyl cellulose MHPC were studied in this work. Conducted research has proven efficiency of 8% CMHC which allowed for proper granulation and carbonization and reached the best parameters. Single- and double-stage activation was investigated for AC with this binder. For newly manufactured AC BET surface and pore volume increased accordingly from 774 m²/g and 0.58 cm³/g (1-stage) to 968 m²/g and 0.72 cm³/g (2-stage). Chemical elemental features of surface of the best AC showed beside elementary carbon also calcium, silicon and aluminum ions as well as groups with an acidic character, phosphates, sulphates and chlorides. The new AC had a higher Mechanical Strength reaching 99.9% and a lower Ash content and Volatile Matter than AC manufactured with previous binder—molasse. The new AC is intended to be directed for full production line and implementation to usage after positive certification. It may be useful in water treatment. It will also find application in the treatment of industrial and municipal wastewater. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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12 pages, 8092 KiB

Open AccessEditor’s ChoiceArticle

A Study of the Adsorption Properties of Individual Atoms on the Graphene Surface: Density Functional Theory Calculations Assisted by Machine Learning Techniques

by Jingtao Huang, Mo Chen, Jingteng Xue, Mingwei Li, Yuan Cheng, Zhonghong Lai, Jin Hu, Fei Zhou, Nan Qu, Yong Liu and Jingchuan Zhu

Materials 2024, 17(6), 1428; https://doi.org/10.3390/ma17061428 - 20 Mar 2024

Cited by 1 | Viewed by 1182

Abstract

In this research, the adsorption performance of individual atoms on the surface of monolayer graphene surface was systematically investigated using machine learning methods to accelerate density functional theory. The adsorption behaviors of over thirty different atoms on the graphene surface were computationally analyzed. [...] Read more.

In this research, the adsorption performance of individual atoms on the surface of monolayer graphene surface was systematically investigated using machine learning methods to accelerate density functional theory. The adsorption behaviors of over thirty different atoms on the graphene surface were computationally analyzed. The adsorption energy and distance were extracted as the research targets, and the basic information of atoms (such as atomic radius, ionic radius, etc.) were used as the feature values to establish the dataset. Through feature engineering selection, the corresponding input feature values for the input-output relationship were determined. By comparing different models on the dataset using five-fold cross-validation, the mathematical model that best fits the dataset was identified. The optimal model was further fine-tuned by adjusting of the best mathematical ML model. Subsequently, we verified the accuracy of the established machine learning model. Finally, the precision of the machine learning model forecasts was verified by the method of comparing and contrasting machine learning results with density functional theory. The results suggest that elements such as Zr, Ti, Sc, and Si possess some potential in controlling the interfacial reaction of graphene/aluminum composites. By using machine learning to accelerate first-principles calculations, we have further expanded our choice of research methods and accelerated the pace of studying element–graphene interactions. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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31 pages, 18408 KiB

Open AccessArticle

Mesoporous Carbons and Highly Cross-Linking Polymers for Removal of Cationic Dyes from Aqueous Solutions—Studies on Adsorption Equilibrium and Kinetics

by Malgorzata Zienkiewicz-Strzalka, Magdalena Blachnio, Anna Derylo-Marczewska, Szymon Winter and Malgorzata Maciejewska

Materials 2024, 17(6), 1374; https://doi.org/10.3390/ma17061374 - 17 Mar 2024

Cited by 3 | Viewed by 1390

Abstract

This study presents the results of applying the methods of synthesizing mesoporous carbon and mesoporous polymer materials with an extended porous mesostructure as adsorbents for cationic dye molecules. Both types of adsorbents are synthetic materials. The aim of the presented research was the [...] Read more.

This study presents the results of applying the methods of synthesizing mesoporous carbon and mesoporous polymer materials with an extended porous mesostructure as adsorbents for cationic dye molecules. Both types of adsorbents are synthetic materials. The aim of the presented research was the preparation, characterisation, and utilisation of obtained mesoporous adsorbents. The physicochemical properties, morphology, and porous structure characteristics of the obtained materials were determined using low-temperature nitrogen sorption isotherms, X-ray diffraction (XRD), small angle X-ray scattering (SAXS), and potentiometric titration measurements. The morphology and microstructure were imaged using scanning electron microscopy (SEM). The chemical characterisation of the surface chemistry of the adsorbents, which provides information about the surface-active groups, the elemental composition, and the electronic state of the elements, was carried out using X-ray photoelectron spectroscopy (XPS). The adsorption properties of the mesoporous materials were determined using equilibrium and kinetic adsorption experiments for three selected cationic dyes (derivatives of thiazine (methylene blue) and triarylmethane (malachite green and crystal violet)). The adsorption capacity was analysed to the nanostructural and surface properties of used materials. The Generalized Langmuir equation was applied for the analysis of adsorption isotherm data. The adsorption study showed that the carbon materials have a higher sorption capacity for both methylene blue and crystal violet, e.g., 0.88–1.01 mmol/g and 0.33–0.44 mmol/g, respectively, compared to the polymer materials (e.g., 0.038–0.044 mmol/g and 0.038–0.050 mmol/g, respectively). The kinetics of dyes adsorption was closely correlated with the structural properties of the adsorbents. The kinetic data were analysed using various equations: first-order (FOE), second-order (SOE), mixed 1,2-order (MOE), multi-exponential (m-exp), and fractal-like MOE (f-MOE). Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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16 pages, 11304 KiB

Open AccessArticle

Impregnated Polymeric Sorbent for the Removal of Noble Metal Ions from Model Chloride Solutions and the RAM Module

by Karolina Zinkowska, Zbigniew Hubicki and Grzegorz Wójcik

Materials 2024, 17(6), 1234; https://doi.org/10.3390/ma17061234 - 7 Mar 2024

Viewed by 844

Abstract

Nowadays, there is a need for new sources of noble metals due to their dwindling natural resources. This paper presents studies on the sorption of noble metals such as Au(III), Pt(IV), Pd(II) and Rh(III) from model chloride solutions on a newly prepared Amberlite [...] Read more.

Nowadays, there is a need for new sources of noble metals due to their dwindling natural resources. This paper presents studies on the sorption of noble metals such as Au(III), Pt(IV), Pd(II) and Rh(III) from model chloride solutions on a newly prepared Amberlite XAD-16–Aliquat 336 sorbent. A “warm impregnation” method without the use of toxic organic solvents was applied to impregnate the polymer matrix. The influence of such factors as hydrochloric acid concentration, sorbent mass and phase contact time was investigated. Kinetic as well as adsorption isotherm studies were carried out. The sorption capacity of the synthesized sorbent was Au(III)—94.34 mg/g, Pt(IV)—45.35 mg/g and Pd(II)—46.03 mg/g. Based on thermodynamic considerations, their sorption proved to be endothermic, as the values of ΔH° > 0. Sorption was spontaneous and favourable (ΔG° < 0). After leaching the RAM module, there was obtained a real solution, in which the metal contents were determined: 38.10 mg/g of gold and 1.76 mg/g of palladium. Totals of 99.9% of gold and 45.4% of palladium were removed from the real leaching solution, with other elements in the solution. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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25 pages, 13315 KiB

Open AccessArticle

A Sustainable Banana Peel Activated Carbon for Removing Pharmaceutical Pollutants from Different Waters: Production, Characterization, and Application

by Osamah J. Al-sareji, Ruqayah Ali Grmasha, Mónika Meiczinger, Raed A. Al-Juboori, Viola Somogyi and Khalid S. Hashim

Materials 2024, 17(5), 1032; https://doi.org/10.3390/ma17051032 - 23 Feb 2024

Cited by 13 | Viewed by 3198

Abstract

Due to the growing concerns about pharmaceutical contamination and its devastating impact on the economy and the health of humans and the environment, developing efficient approaches for removing such contaminants has become essential. Adsorption is a cost-effective technique for removing pollutants. Thus, in [...] Read more.

Due to the growing concerns about pharmaceutical contamination and its devastating impact on the economy and the health of humans and the environment, developing efficient approaches for removing such contaminants has become essential. Adsorption is a cost-effective technique for removing pollutants. Thus, in this work, banana peels as agro-industrial waste were utilized for synthesizing activated carbon for removing pharmaceuticals, namely amoxicillin and carbamazepine from different water matrices. The chemically activated carbon by phosphoric acid (H₃PO₄) was carbonized at temperatures 350 °C, 450 °C and 550 °C. The material was characterized by several techniques such as scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), Boehm titration, point of zero charge (pH_PZC), BET surface area (S_BET), the proximate and ultimate analyses, X-ray powder diffraction (XRD), and thermos-gravimetric analysis (TGA). The SEM of banana peel activated carbon (BPAC) depicted a semi-regular and heterogeneous morphology, characterized by an abundance of pores with diverse forms and sizes. Boehm titration revealed an increase in the amounts of acidic groups by 0.711 mmol/g due to activation by H₃PO₄. FTIR recorded different peaks suggesting significant modifications in the spectroscopic characteristics of the BPAC surface due to the successful activation and adsorption of the pollutant molecules. The pHpzc of BPAC was calculated to be 5.005. The S_BET surface area dramatically increased to 911.59 m²/g after the activation. The optimum conditions were 25 °C, a materials dosage of 1.2 g/L, a saturation time of 120 min, a pollutants mixture of 25 mg/L, and a pH of 5. Langmuir exhibits a slightly better fit than Freundlich with a low value of the residual sum of squares (SSE) and the data were better fitted to the pseudo-second-order kinetic. Furthermore, the efficacy of BPAC in eliminating pharmaceuticals from Milli Q water, lake water, and wastewater was successfully investigated over the seven cycles. The results of the present work highlighted a potential usage of agro-industrial waste in eliminating organic micropollutants while exhibiting sustainable management of this waste. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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19 pages, 4096 KiB

Open AccessArticle

Dynamic Adsorption of a Cationic Dye onto Wool Fibers as Column-Filling Media: Response Surface Optimization and Fixed-Bed Adsorption Modeling

by Bogdan-Constantin Condurache, Corneliu Cojocaru, Alexandra Bargan, Petrisor Samoila and Valeria Harabagiu

Materials 2024, 17(4), 790; https://doi.org/10.3390/ma17040790 - 6 Feb 2024

Cited by 1 | Viewed by 993

Abstract

This study reports a simple and low-cost method for water purification using recyclable natural fibers (coarse wool fibers) as column-filling media for adsorption in the dynamic mode. As an instance of a dissolved organic pollutant, a cationic dye (basic blue 9, BB9) was [...] Read more.

This study reports a simple and low-cost method for water purification using recyclable natural fibers (coarse wool fibers) as column-filling media for adsorption in the dynamic mode. As an instance of a dissolved organic pollutant, a cationic dye (basic blue 9, BB9) was assayed. According to the Langmuir isotherm (recorded at 300 K), the calculated maximum adsorption capacity of the fibrous material was found to be 24.86 mg/g for the retention of BB9. Response surface methodology (RSM) was employed for the design of experiments and the model-based optimization of the adsorption process performed in the dynamic regime (fixed-bed column). The optimal conditions provided by RSM indicated an adsorbent column height of H = 13.5 cm and a feed flow rate of F_v = 3 mL/min; these operating parameters ensured a color removal efficiency of 92.56% after 240 min of contact time. The recorded breakthrough curve under the optimal conditions was further interpolated using five quantitative mathematical models (Adams–Bohart, Thomas, Yoon–Nelson, Yan, and Clark) to assess the dynamic behaviors in the fixed-bed column. The best goodness-of-fit was achieved for the Thomas and Yoon–Nelson models. Thus, the coarse wool fibers used in a fixed bed demonstrated a relevant efficiency in the removal of cationic organic pollutants from contaminated water. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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14 pages, 2120 KiB

Open AccessArticle

Microwave-Assisted Fabrication of Fugus-Based Biocarbons for Malachite Green and NO₂ Removal

by Aleksandra Bazan-Wozniak, Sultan Yagmur-Kabas, Agnieszka Nosal-Wiercińska and Robert Pietrzak

Materials 2023, 16(24), 7553; https://doi.org/10.3390/ma16247553 - 7 Dec 2023

Cited by 2 | Viewed by 986

Abstract

The aim of the current study was to produce biocarbons through the activation of carbon dioxide with the extraction residues of the fungus Inonotus obliquus. To achieve this goal, a microwave oven was used to apply three different activation temperatures: 500, 600, [...] Read more.

The aim of the current study was to produce biocarbons through the activation of carbon dioxide with the extraction residues of the fungus Inonotus obliquus. To achieve this goal, a microwave oven was used to apply three different activation temperatures: 500, 600, and 700 °C. Low-temperature nitrogen adsorption/desorption was employed to determine the elemental composition, acid-base properties, and textural parameters of the resulting carbon adsorbents. Subsequently, the produced biocarbons were evaluated for their efficiency in removing malachite green and NO₂. The adsorbent obtained by activation of the precursor in 700 °C had a specific surface area of 743 m²/g. In the aqueous malachite green solution, the highest measured sorption capacity was 176 mg/g. Conversely, under dry conditions, the sorption capacity for NO₂ on this biocarbon was 21.4 mg/g, and under wet conditions, it was 40.9 mg/g. According to the experimental findings, surface biocarbons had equal-energy active sites that interacted with the dye molecules. A pseudo-second-order kinetics model yielded the most accurate results, indicating that the adsorption of malachite green was driven by chemisorption. Additionally, the study demonstrates a clear correlation between the adsorption capacity of the biocarbons and the pH level of the solution, as it increases proportionately. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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25 pages, 4156 KiB

Open AccessArticle

Microwave-Prepared Quantum Dots and Their Potential Applications as Adsorbents and Chemosensors

by Hebat-Allah S. Tohamy, Mohamed El-Sakhawy, El Barbary Hassan and Samir Kamel

Materials 2023, 16(20), 6722; https://doi.org/10.3390/ma16206722 - 17 Oct 2023

Cited by 10 | Viewed by 1155

Abstract

A combination of different eco-friendly materials prepared promising fluorescent quantum dots (QDs) through the one-step process using the microwave heating of urea with cellulose, chitosan, and biochar. Characterizations of the prepared QDs, including the investigation of their structure by infrared spectroscopy, Raman analysis, [...] Read more.

A combination of different eco-friendly materials prepared promising fluorescent quantum dots (QDs) through the one-step process using the microwave heating of urea with cellulose, chitosan, and biochar. Characterizations of the prepared QDs, including the investigation of their structure by infrared spectroscopy, Raman analysis, X-ray diffraction, thermal gravimetric analysis, morphology, and optical properties, were performed. The results showed that QDs possess a small size, high UV absorption, and excitation wavelength-dependent fluorescence. The prepared QDs were also tested for metal ions removal from aqueous solutions. The adsorption at different contact times was investigated to optimize the adsorption efficiency of the prepared QDs. All QDs were found to be an ideal sorbent for Cr(II), Cu(II), Mn(II), and Pb(II). From the data, Cr(II) was more highly adsorbed than other metal ions. The results of the kinetic investigation showed that the pseudo-second-order kinetic model fit the adsorption process effectively. In addition, the fluorescence spectra of QDs were changed after the adsorption of metal ions; hence, the prepared QDs could be utilized in environmental sectors such as wastewater pollution detection, adsorption, and chemical sensing applications. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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Review

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24 pages, 16818 KiB

Open AccessReview

New Adsorption Materials for Deep Desulfurization of Fuel Oil

by Xiaoyu Qiu, Bingquan Wang, Rui Wang and Ivan V. Kozhevnikov

Materials 2024, 17(8), 1803; https://doi.org/10.3390/ma17081803 - 14 Apr 2024

Cited by 3 | Viewed by 1962

Abstract

In recent years, due to the rapid growth of mankind’s demand for energy, harmful gases (SOx) produced by the combustion of sulfur-containing compounds in fuel oil have caused serious problems to the ecological environment and human health. Therefore, in order to solve this [...] Read more.

In recent years, due to the rapid growth of mankind’s demand for energy, harmful gases (SOx) produced by the combustion of sulfur-containing compounds in fuel oil have caused serious problems to the ecological environment and human health. Therefore, in order to solve this hidden danger from the source, countries around the world have created increasingly strict standards for the sulfur content in fuel. Adsorption desulfurization technology has attracted wide attention due to its advantages of energy saving and low operating cost. This paper reviewed the latest research progress on various porous adsorption materials. The future challenges and research directions of adsorption materials to meet the needs of clean fuels are proposed. Full article

(This article belongs to the Special Issue Adsorption Materials and Their Applications)

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