Adsorption Efficiency Research Articles

DFT theoretical analysis, experimental approach, and RSM process to understand the congo red adsorption mechanism on Chitosan@Graphene oxide beads

The presence of Congo red in wastewater poses significant environmental and health risks due to its toxic and carcinogenic properties. As a synthetic azo dye commonly used in the textile industry, Congo red is resistant to degradation, leading to persistent contamination in water bodies. The study focused on evaluating the efficacy of novel composite beads made from chitosan and graphene oxide as adsorbents for eliminating Congo Red from water solutions. It systematically examined various experimental factors including initial concentration, pH levels, mass of adsorbent, contact duration, and temperature, aiming to optimize the adsorption process. The composite chitosan graphene oxide beads were analyzed using several techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) method for specific surface area determination. The study involved extracting chitosan from shrimp shells and synthesizing graphene oxide from graphite using the Hummers method to enhance Congo Red adsorption efficiency. Comprehensive analysis of the composite beads assessed their physical and functional properties using various techniques. X-ray diffraction and infrared analysis identified their adsorption capabilities, while SEM and BET analysis characterized the porous surface structure of the beads. Maximum adsorption efficiency of 169.49 mg/g was achieved with an adsorbent mass of 0.05 g at pH 3. Kinetic, isotherm, and thermodynamic studies indicated an endothermic process following pseudo-second-order kinetics and the Langmuir isotherm model. The high regression coefficient R 2=0.9953 indicates the strong validity of employing Response Surface Methodology combined with the Box-Behnken Design (RSM-BBD) for accurately predicting the percentage of CR removal through adsorption. Theoretical Density Functional Theory (DFT) analysis elucidated interactions between Congo Red and the reactive sites within the chitosan/graphene oxide beads, providing insights into the adsorption mechanism.

Tunable sulfur vacancies in amorphous-crystalline AC-Bi2S3-x@C derived from CAU-17 for efficient capture of radioiodine: Comparison of sulfur vacancies in amorphous and crystalline structures

Solid-phase adsorption has been recognized as an effective method for the control of volatile radioactive iodine in spent fuel reprocessing plant off-gases. However, it is still a challenge to develop efficient and stable iodine capture adsorbents. In this work, sulfur-vacancy-rich amorphous-crystalline AC-Bi2S3-x@C was prepared by solvothermal vulcanization using CAU-17 as a precursor. Based on the synergistic effect of the amorphous structure and sulfur vacancy defects, AC-Bi2S3-x@C exhibited fast adsorption equilibrium time (15 min), distinguished iodine adsorption capacity (1763.9 mg g−1), high percentage of chemical adsorption (93.4 %) as well as favorable thermal and irradiation stability. Adsorption experiments and theoretical calculations verified that the amorphous structure not only enhance the charge transfer between sulfur vacancy defects and iodine molecules, but also offers rapid diffusion channels for iodine molecules to the interior of the adsorbent and sufficient internal binding sites to promote iodine molecule adsorption in its interior. The used adsorbent showed high iodine retention (92.3 %) and excellent chemical durability (normalized iodine leaching rate of 4.63 × 10-5 g m−2 d-1) in glass solidification. In general, this work presented a new concept in the design and synthesis of efficient radioactive iodine capture materials.

Single-step template-free synthesis of fluoro-functionalized covalent organic frameworks with a tunable hollow structure for extraction of phthalate acid esters from human urine

Phthalate acid esters (PAEs) are recognized as endocrine disruptors, exhibit carcinogenic characteristics, and have the potential to impair fertility, thereby posing significant risks to both the environment and human health. Consequently, biomonitoring and exposure assessment of PAEs are of paramount importance. Presently, the majority of detection methods for PAEs are centered on aqueous matrices, and the development of techniques for the identification of PAEs in complex matrices remains an area of active research. This paper designed and synthesized a novel fluoro-functionalized hollow covalent organic framework (F-HCOF), characterized by a tunable hollow spherical structure and enriched with fluorine functional groups, through a one-step self-template approach, which effectively regulated the formation of the hollow structure. The synthesized F-HCOF with tunable hollow structures and abundant F functional groups provided efficient diffusion pathways and adsorption sites, facilitating robust and selective adsorption of the target PAEs. Using F-HCOF as a coating, a solid-phase microextraction method was developed to extract PAEs from complex matrices. The method exhibited limits of detection ranging from 0.0108 to 0.0581 ng L−1, with enrichment factors spanning from 2535.3 to 8985.3. The self-made F-HCOF fibers demonstrated the capability to effectively enrich PAEs under various interference conditions, further verifying their feasibility for practical sample analysis. This work provided a strategic approach for the synthesis of F-functionalized hollow COF adsorbents and explored the formation process of hollow spheres. It enables matrix interference-resistant analysis of PAEs, and offers a practical method for studying PAEs exposure and metabolism within the human body.

A study combining experimental, computationaland machine learning approaches on the removal of tartrazine dye using carbon nanotubes

This study addresses the environmental threat posed by synthetic hazardous dyes, particularly tartrazine, in water bodies. We present an integrated method for the effective removal of tartrazine using Multiwalled Carbon Nanotubes (MWCNTs) synthesized via Chemical Vapor Deposition. Extensive characterization confirms MWCNTs as highly efficient adsorbents, with batch adsorption studies demonstrating their remarkable ability to remove 98.39% of tartrazine from water within 60 min at room temperature and pH 6. Density Functional Theory calculations provide molecular insights into the adsorption process, identifying six interaction possibilities and the most reactive site on tartrazine. Additionally, Machine Learning and Deep Learning models offer cost-effective predictive tools for efficient dye removal, with the deep learning model (ANN) proving most effective. This interdisciplinary approach marks a significant advancement in water treatment and environmental remediation, with future research focusing on scaling MWCNT synthesis and exploring diverse practical applications.

Preparation of efficient adsorbent for methylene blue and Congo red by co-hydrothermal of red mud with food waste compost

Herein, a novel red mud-carbon composite (RFBC) was prepared through co-hydrothermal treatment of red mud with food waste compost, and its adsorption property was evaluated on Methylene blue (MB) and Congo red (CR), selected model dyes in aqueous solution. The adsorption process conformed to pseudo-second-order kinetic, intraparticle diffusion, and the Redlich-Peterson isotherm models. RFBC exhibited a maximum sorption of 124.06 mg·g-1 for MB and 2959.35 mg·g-1 for CR at 298 K. Isothermal and thermodynamic studies demonstrated that adsorption of MB and CR by RFBC were spontaneous and exothermic, governed by physisorption and chemisorption. Furthermore, the possible adsorption mechanisms are pore filling, electrostatic attraction, hydrogen bonding, and π-π interactions. After five consecutive adsorption-desorption cycles were completed, the RFBC demonstrated an adsorption efficiency exceeding 70 % in relation to dyes, affirming its exceptional reusability. This study suggested this red mud-carbon composite had high potential as a novel and promising adsorbent for dye removal from wastewater.

Synthesis and application of SBA-15 adsorbent for the removal of organic and inorganic substances.

This study investigates the adsorption of pollutants with different chemical structures; organic Naphtol Green B (NGB) dye and copper on a nanocomposite material with a hexagonal structure of the SBA-15 type. This research is divided into two main parts: the first carries out the synthesis of SBA-15 (Santa Barbra Amourphous) and its derivatives phases functionalized by 3-aminopropyl-triethoxylane (APTES) and calcined at 823K. The second part presents the influence of the adsorption conditions on the adsorption efficiency of NGB dye and copper. High-resolution X-ray diffractogram (XRD) showed three distinct peaks characteristic of highly ordered mesoporous material. Nitrogen adsorption-desorption isotherm of SBA-15 at 77K° is type IV typical of mesoporous materials. In addition, Fourier transform infrared spectroscopy (FT-IR) was also used in the characterization before and after the adsorption of the selected pollutants. At optimal conditions of pH 5.2, initial concentration of 50mg/L, adsorbent dosage of 20mg, and at adsorption time of 90min the maximum removal of pollutants reached 76% and the adsorption capacity was 227.25mg/g for NGB dye and 221.006mg/g for copper. Furthermore, the adsorption kinetics followed the pseudo-second-order model, indicating that chemisorption was the dominant mechanism and the Sips isotherm model best described the adsorption data. Our research demonstrates that the SBA-15 material after modification is an effective adsorbent for removing effluents regardless of their different chemical structure (organic and inorganic).

Aminomethanesulfonic acid grafted polyamidoxime fibers with hydrophilicity, salt-tolerance and antimicrobial properties for highly efficient uranium extraction from seawater

Uranium extraction from seawater plays a key role in redefining the declining uranium reserves to afford sustainable nuclear power. However, it is an urgent need to develop adsorbents simultaneously possessing enhanced efficiency, collect ability, salt resistance, antibacterial properties and economy to massively extract uranium from seawater. Herein, aminomethanesulfonic acid grafted polyamidoxime fibers (PAO-AMS-A) with hydrophilicity, salt resistance and antibacterial properties were prepared. The resulting fibers display high salt resistance and high uranium uptake capacity, providing the fibers a very high adsorption efficiency of 554.09 mg g−1 in pure uranium solution, 205.43 mg g−1 and 473.44 mg g−1 in 8 ppm and 20 ppm uranium spiked seawater and 10.04 mg g−1 in real seawater, respectively. Furthermore, the material exhibited good salt tolerance, and the uranium adsorption capacity was still as high as 597.97 mg g−1 in high concentrations of NaCl solution. Note that PAO-AMS-A has also good antibacterial activity, the antibacterial rate against bacteriais cultured in seawater is up to 93.49 %. Overall, PAO-AMS-A fibers are promising in industrial uranium extraction from seawater due to their high adsorption efficiency, salt resistance and antimicrobial properties.

Deciphering heterojunction layered double hydroxide-polyaniline-carbon nanotubes for phosphorus capture in capacitive deionization

The capacitive deionization (CDI) has emerged as a robust technology due to its effective performance in removing and recovering phosphate in wastewater. However, there are still challenges in achieving fast charge transfer and high capacity phosphorus storage simultaneously. In this study, a layered double hydroxide-polyaniline-carbon nanotubes composite material (ZnFe-PANI/CNT) with heterojunction and pseudocapacitive characteristics was fabricated via a simple and effective precipitation strategy. The existence of heterojunction and pseudocapacitance of ZnFe-PANI/CNT was confirmed through material performance testing Moreover, with its fast charge transfer and high ion storage performance, it was achieved high phosphate adsorption efficiency (94 %) and sustainable electrode regeneration in low concentration phosphate wastewater. Ultraviolet photoelectron spectroscopy (UPS) and density functional theory revealed the ability to accelerate charge transfer, which was contributed by the heterojunction ZnFe-PANI/CNT. In addition, it was found that the synergies of electrostatic attraction, ligand exchange and surface complexation contributed to the high phosphate capture ability in the acidic environments. The binuclear bidentate or mononuclear bidentate structures dominated the surface configuration of phosphate adsorption at pH 4–9.

A high‐temperature resistant benzimidazole‐based porous polymer for efficient adsorption of trinitrotoluene in aqueous solution

AbstractA novel benzimidazole‐based porous polymer, denoted as PTBI, was synthesized utilizing self‐synthesized 1,3,5‐tris(1H‐benzo[d]imidazol‐2‐yl)benzene (TBI) and 4,4′‐difluorobenzophenone as primary materials via a CN coupling reaction, followed by a freeze‐drying process. PTBI displayed commendable thermal stability, as evidenced by a temperature of 475°C at which a 5% weight loss occurred and a char yield of up to 65% at 800°C. Trinitrotoluene (TNT) was effectively adsorbed by PTBI in aqueous solutions, thanks to the combined effects of three π–π interactions and one dipole–π interaction. At 25°C, PTBI achieved a maximum adsorption capacity as high as 280.8 mg/g, with approximately 60% of this capacity attained within just 1 h. Furthermore, a thermodynamic analysis showed that the adsorption of TNT by PTBI was a spontaneous, exothermic process that was followed by a decrease in entropy. It is noteworthy that following five adsorption and desorption cycles, the adsorption efficiency held steady at a relatively high level using acetone as the eluent. These promising results underscore PTBI's significant potential in the realm of TNT wastewater treatment, positioning it as a compelling candidate for further research and application under extreme condition in this field.

Causative mechanisms limiting the removal efficiency of short-chain per- and polyfluoroalkyl substances (PFAS) by activated carbon

Short-chain per and polyfluoroalkyl substances (PFAS) have been found to be relatively high in water treatment systems compared to long-chain PFAS because of the unsatisfactory adsorption efficiency of short-chain PFAS. Knowledge about why short-chain PFAS are less removed by porous carbon is very limited. The study focused on providing causal mechanisms that link the low adsorption of short-chain PFAS and proposing an improved method for removing both short- and long-chain PFAS. The long-chain PFAS with higher hydrophobicity diffused more quickly than the short-chain PFAS due to stronger partitioning driving forces. In the initial adsorption stage, therefore, pores of activated carbon were blocked by long-chain PFAS, which makes it difficult for the short-chain PFAS to enter the internal pores. Although several short-chain PFAS diffuse into the pores, the relatively more hydrophilic short-chain congeners cannot be fully adsorbed on activated carbon due to limited positively charged sites. Moreover, compared to larger particle sizes, smaller activated carbon particles have shorter pore channels near the surface, reducing the risk of pore-blocking and ensuring the pores remain accessible for more efficient adsorption. Additionally, these smaller particles offer a greater external surface area and more functional groups, which enhance the adsorption capacity. It indicates that the smaller particle size of activated carbon would have a positive effect on the short-chain PFAS removal.

Preparation of Polydopamine-Based Electrospun Nanofibers as an Efficient Adsorbent for Solid-Phase Extraction of Trace Mycotoxins Followed by HPLC

Preparation of Polydopamine-Based Electrospun Nanofibers as an Efficient Adsorbent for Solid-Phase Extraction of Trace Mycotoxins Followed by HPLC

Exploring sustainable solutions: Utilizing recycled coffee grounds as a new bio‐adsorbent material for removal of Pb(II) ions from water

AbstractThis study investigates the potential of utilizing spent coffee grounds (SCG) treated with Ca(OH)2 as an adsorbent for the removal of lead (Pb(II)) ions from aqueous solutions. The SCG was subjected to sequential treatments, including washing, drying, sieving, and immersion in Ca(OH)2 solutions of varying concentrations. Adsorption experiments were conducted under different conditions to evaluate the efficiency of the adsorbent, including variations in contact time, solution pH, adsorbent dosage, temperature, and initial Pb(II) ion concentration. Characterization of the SCG before and after treatment was performed using Fourier transform infrared spectroscopy. The results revealed significant changes in the structural properties of the SCG after treatment with Ca(OH)2, leading to enhanced adsorption performance. The adsorption experiments demonstrated that the efficiency of Pb(II) ion removal was influenced by factors such as contact time, solution pH, adsorbent dosage, temperature, and initial Pb(II) ion concentration. Optimal conditions for maximum adsorption efficiency were identified as a contact time of 270 min, pH 6, adsorbent dosage of 1 g, and temperature of 313 K, resulting in a maximum adsorption capacity qmax of 18.69 mg g−1. The highest desorption rate was observed using HNO3, measured at 90.6%. The reusability efficiency of the adsorbent material was 87.98% in the first use, decreased to 75.41% after five reuses, and further reduced to 39.96% after ten reuses, indicating a decline in performance with repeated use. These findings highlight the potential of SCG as an effective and environmentally friendly adsorbent for the removal of potentially toxic elements from aqueous solutions.

Insights into bismuthene and antimonene as cisplatin drug carriers: A theoretical comparative investigation

While effective targeted delivery is a challenge in nanomedicine for the delivery of anti-cancer drugs, this work focuses on the potential use of Bismuthene and antimonene nanosheets as nanocarriers for cisplatin anti-cancer using DFT methods. The results indicate that, compared to antimonene, bismuthene demonstrates significantly better physical stability, drug release rate, solubility, and biocompatibility, making it an excellent candidate for drug delivery systems. The parallel and perpendicular orientations of the anticancer drug were adsorbed on both nanosheets; the parallel configuration was the most energetically favored with an adsorption energy of −0.79 eV at the parallel site. A charge transfer from the drug to the bismuthene sheet is also revealed by the electronic charge analysis and DOS calculation, thus confirming efficient drug adsorption. Modeling a proton attack on the drug and the carrier surface near the adsorption sites was performed to model drug release, showing the stability and potential of bismuthene in this aspect of drug release mechanisms. Further, with an approach to studying its interactions with biomolecules, interactions of the drug molecule have been analyzed with amino acids, showing that drugs interact efficiently. Further assessments concerning work function, recovery time, electron localization function, and frontier molecular orbital analyses leave no doubt that bismuthene has beneficial features over antimonene. These thorough assessments present bismuthene as a more promising nanocarrier for the delivery of anti-cancer drugs and open a potential pathway to enhance the efficacy of strategies against cancer treatment.

Uranium extraction from wastewater by heteroatom-doped carbon microspheres derived from polyphosphazene loading with zinc oxide

The effective management of uranium-contaminated wastewater is crucial for environmental protection and public health safety. In this context, a novel composite was synthesized involving the intergration of zinc oxide into heteroatom-doped polyphosphazene carbon microspheres (TAC/ZnO) by hydrothermal method. The incorporation of ZnO into TAC significantly enhanced the porosity, offering more adsorption sites and improving the uranium adsorption performance. The optimal adsorption experiment achieved a remarkable adsorption capacity of 513.9 mg.g−1 for U(VI) at a pH of 5.5 within just 80 min. Additionally, the adsorption process was found to be endothermic and spontaneous, following both the Langmuir isothermal adsorption model and the pseudo-second-order kinetic model. Moreover, the TAC/ZnO presented higher selectivity for U(VI) in the presence of other cations. Even after 8 cycles, TAC/ZnO maintained a good removal rate for U(VI), decreasing from 97.54 % to 81.95 %. Furthermore, the findings from X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations indicated that the adsorption mechanism of U(VI) on TAC/ZnO may involve the coordinated interaction between oxygen atoms in Zn-O and nitrogen atoms in pyridinie-N-oxide with uranyl ions. Overall, this study presents an easily prepared, cost-effective, and highly efficient adsorbent that offers potential for large-scale production and practical application in purifying radioactive wastewater.

Sustainable solution for wastewater management: Fabrication of cost-effective β-cyclodextrin incorporated chitosan polyvinyl alcohol composite hydrogel film for the efficient adsorption of anionic congo red and tartrazine dyes

Dyes are an integral part of leather, textiles, food, and packaging materials, providing aesthetic appeal to the finished article. These industries use large amounts of water, creating wastewater with harmful, toxic, and hazardous pollutants, posing significant health and environmental risks to the public and ecological system. Therefore, to resolve this issue, a superabsorbent β-cyclodextrin incorporated chitosan polyvinyl alcohol cross-linked with citric acid composite hydrogel film (β-CD/Ch/PVA) has been developed for the effective adsorption of congo red (CR) and tartrazine dyes (TG). The Fourier-transform infrared spectroscopic (FTIR) analysis confirmed the presence of –OH, –NH2 functional groups in hydrogel film. The rough surface morphology was obtained through Field emission scanning electron microscopic (FESEM) analysis. Brunauer-Emmett-Teller (BET) method gave the surface area of hydrogel, which is 17.34 m2/g with pore diameter of 4.12 nm, indicating its mesoporous nature. Adsorption parameters like contact time, temperature, pH, initial concentration of dyes, and dosage of hydrogel have been optimized by batch adsorption studies and the Box-Behknen Design Model. In batch experiments, the hydrogel film effectiveness was confirmed, achieving high removal efficiencies of 95.38 % and 96.3 % for CR and TG dyes at pH 7 and 6, respectively. The adsorption process followed the pseudo-second-order kinetics and Langmuir model at room temperature for both dyes, and the maximum adsorption capacity was found to be 366.34 mg/g, 1436.04 mg/g for CR and TG dyes, respectively. The thermodynamic study revealed that the adsorption of dyes was spontaneous and endothermic in nature. The electrostatic interactions and hydrogen bonding between the hydrogel and dye molecules were responsible for the adsorption. This hydrogel film can be reused for 5 consecutive adsorption–desorption cycles for both dyes, maintaining upto 85 % in removal efficiency. Hence, the synthesized β-cyclodextrin incorporated chitosan polyvinyl alcohol composite hydrogel film holds great potential for the remediation of wastewater effluents and addressing environmental issues.

Floatable expanded perlite-loaded Z-scheme n-C3N5/Ag2CO3 core-shell structure with C-defects for enhanced adsorption and photodegradation of microcystin-LR: Insights into performance and mechanism

Efficient in-situ treatment of high concentrations microcystin-LR in surface waters is especially challenging. Herein, spherical floatable Z-scheme core-shell photocatalyst EP@n-C3N5/Ag2CO3 (EP@CNAC) with carbon defects was constructed using expanded perlite (EP) as floating carrier for efficient adsorption and degradation of microcystin-LR. The carbon defect sites and electron density distribution of C3N5 were investigated by DFT calculation. Benefited from synergistic effects of morphology and defect engineering, Z-scheme heterojunction, and floatability, the carrier migration kinetics and solar spectral responsiveness of EP@CNAC-3 were significantly enhanced, and 97 % of microcystin-LR was degraded within 16 min. The LC-MS, Fukui index, and electrostatic potential of microcystin-LR revealed that Adda side chain was cleaved by electrophilic attack of 1O2, while ring-opening reaction and decarboxylation were caused by nucleophilic attack of •O2- and strong oxidative properties of h+, respectively. These findings are expected to bring new insights into design of innovative floating photocatalysts and in-situ remediation mechanism of microcystin-LR.

Design of Mixed-Metal MOF-74-MgNi for Water Adsorption-Driven Solar Thermal Energy Storage and Heat Transformation Applications.

Adsorption solar thermal energy storage and heat transformation are ecologically benign and energy-efficient technologies. Efficient adsorbents are the key to this technology. In this paper, two metal ions, Mg2+ and Ni2+, were introduced into the metal-organic framework MOF-74. The synthesis conditions were adjusted to obtain MOF-74 with a high water adsorption capacity and stability. The results show that MOF-74-MgNi-2 has the maximum water adsorption capacity. At a low moisture pressure P/P0 = 0.1, its water adsorption capacity is 0.44 g/g, 0.12 g/g, and 0.10 g/g greater than that of MOF-74-Mg and MOF-74-Ni, respectively. Its saturated water adsorption capacity at P/P0 = 0.9 is as high as 0.62 g/g, which is 1.3 times that of MOF-74-Ni and 1.1 times that of MOF-74-Mg, respectively. Its superior water adsorption capacity is explained by the combination of experiment and molecular simulation, which takes into account the pore structure and electrostatic potential energy distribution. Its thermal breakdown temperature is greater than 250 °C. Its water adsorption capacity decreases by only 9.0% in the 10th cycle. Under conventional refrigeration conditions, its refrigeration coefficient and working capacity are 0.75 and 0.43 cm3/cm3, respectively, which are greater than those of the majority of the regularly used adsorbents. In addition, it satisfies the primary technological goals of adsorption-based thermal batteries with a heat storage capacity of up to 1394 kJ/kg. The mixed-metal method is shown to be useful in the design of high-performance MOF-74 for solar thermal energy storage and heat transformation.

Alginate-Based Hydrogel Bead Reinforced with Montmorillonite Clay and Bacterial Cellulose-Activated Carbon as an Effective Adsorbent for Removing Dye from Aqueous Solution.

According to environmental concerns related to water pollution, this study aims to develop a novel hydrogel bead as a biocompatible and efficient adsorbent by integrating bacterial cellulose-activated carbon (BCAC) and montmorillonite (MT) in alginate hydrogel (ALG). The ionotropic gelation method was applied to the fabrication of BCAC/MT/ALG hydrogel beads. The BCAC/MT/ALG hydrogel bead exhibited significantly higher tensile strength, Young's modulus, and thermal stability, with ~1.4 times higher adsorption uptake of methylene blue (MB) from aqueous solution as compared to the pristine ALG bead. The textural properties, including specific surface area and porosity, were beneficial to accommodate the size of cationic MB as the target molecule. This resulted in a remarkable MB adsorption uptake of 678.2 mg/g at pH 7 and 30 °C. The adsorption isotherm showed the best fit for the nonlinear Redlich-Peterson isotherm model. Experimental adsorption data were well-described by the pseudo-second order kinetic model, with R2 values reaching 0.997. In addition, the adsorbent bead demonstrated easy regeneration with high reusability with approximately 75% of MB removal after being used for six cycles. Therefore, BCAC/MT/ALG bead represents an eco-friendly, cost-effective, and highly efficient adsorbent for MB removal from water and could potentially be used for removal of a wide range of cationic dye pollutants from wastewater.

Enhanced sonophoto-catalytic and adsorption capabilities of Fe3O4@MC/MWCNT-CuO/Ag for petrochemical organic pollutants degradation from industrial process streams

To address the problem of petrochemical organic pollutants in water, specifically monoethylene glycol (MEG) present in industrial process streams, in this research, we synthesized and evaluated a multifunctional nanocomposite, Fe3O4@MC/MWCNT-CuO/Ag. The nanocomposite was produced by combining magnetic Fe3O4 nanoparticles, methylcellulose (MC), multi-walled carbon nanotubes (MWCNTs), and CuO/Ag nanoparticles by an integrated synthesis process. A consistent dispersion of nanoparticles, with diameters ranging from 30-40 nm, was discovered by FESEM analysis, showing effective integration without aggregation. Effective synthesis was demonstrated by well-doped and evenly dispersed CuO and Ag nanoparticles. Functional groups that improve electrostatic interactions with contaminants hence enhancing catalytic performance and adsorption efficiency, were validated by FTIR analysis. XRD indicated an unchanged crystal structure with an average crystallite size of 8.67 nm. The anticipated elemental composition was verified by EDS & mapping. A VSM study revealed magnetic characteristics (9.33 emu/g) that simplify nanocomposite separation and reuse. TGA proved thermal stability to be up to 600 °C. A BET study showed a highly specific surface area of 67.661 m2/g, enhancing adsorption. According to DRS and PL studies, the bandgap was lowered by 1.31 eV, which led to better optical absorption. The nanocomposite exhibited notable MEG removal efficiency, with 72 % in adsorption, 65 % in photocatalysis, and 56 % in sonocatalysis. This makes it a promising alternative for the remediation of organic pollutants in water treatment.

Advanced biopolymer-based Ti/Si-terephthalate hybrid materials for sustainable and efficient adsorption of the tetracycline antibiotic

This study involves the synthesis of an organic-inorganic hybrid material consisting of Ti/Si-terephthalate (Ti-TPA-Si) in a 1:1:1 ratio using sol-gel method and its reaction with cellulose and chitosan (Ti-TPA-Si-C and Ti-TPA-Si-CS). Characterization techniques such as XRD, FTIR, SEM, EDS, XPS, BET, TGA, and DTA were used. The incorporation of biopolymers (cellulose and chitosan) into the Ti/Si-terephthalate structure improved the morphology and textural properties of the hybrid materials, leading to increased adsorption capacity and sustainability. Adsorption experiments reveal that Ti-TPA-Si, Ti-TPA-Si-C, and Ti-TPA-Si-CS hybrid materials exhibit a high affinity towards tetracycline, achieving remarkable adsorption efficiencies of 88.27, 89.60, and 88.98 %, respectively. Isotherm studies indicate that the adsorption process follows both Langmuir (R2 = 0.971, 0.990, and 0.994) and Dubinin-Radushkevich (R2 = 0.922, 0.965, and 0.949) isotherm models. According to the Langmuir model, the maximum adsorption capacity (qm) of Ti-TPA-Si, Ti-TPA-Si-C, and Ti-TPA-Si-CS adsorbents was found to be 24.10, 33.56, and 26.59 mg/g, respectively. Kinetic studies indicate that the adsorption process follows both pseudo-second-order (R2 = 0.998, 0.984, and 0.989) and intra-particle diffusion (R2 = 0.995, 0.994, and 0.988) models. Thermodynamic studies reveal that adsorption processes are spontaneous and endothermic in nature. Reusability studies demonstrate their potential for repeated use without significant loss in performance.