High Adsorption Rate Research Articles

Amino-Functionalized Metal-Organic Frameworks Featuring Ultra-Strong Ethane Nano-Traps for Efficient C2H6/C2H4 Separation.

Developing high-performance porous materials to separate ethane from ethylene is an important but challenging task in the chemical industry, given their similar sizes and physicochemical properties. Herein, a new type of ultra-strong C2H6 nano-trap, CuIn(3-ain)4 is presented, which utilizes multiple guest-host interactions to efficiently capture C2H6 molecules and separate mixtures of C2H6 and C2H4. The ultra-strong C2H6 nano-trap exhibits the high C2H6 (2.38mmolg-1) uptake at 6.25kPa and 298K and demonstrates a remarkable selectivity of 3.42 for C2H6/C2H4 (10:90). Additionally, equimolar C2H6/C2H4 exhibited a superior high separation potential ∆Q (2286mmolL-1) at 298K. Kinetic adsorption tests demonstrated that CuIn(3-ain)4 has a high adsorption rate for C2H6, establishing it as a new benchmark material for the capture of C2H6 and the separation of C2H6/C2H4. Notably, this exceptional performance is maintained even at a higher temperature of 333K, a phenomenon not observed before. Theoretical simulations and single-crystal X-ray diffraction provide critical insights into how selective adsorption properties can be tuned by manipulating pore dimensions and geometry. The excellent separation performance of CuIn(3-ain)4 has been confirmed through breakthrough experiments for C2H6/C2H4 gas mixtures.

Efficient adsorption of flavonoids on amino-functionalized ZIF-8/chitosan aerogels

Covalent organic structures (MOFs), known for their exceptional properties in separation and purification, have garnered significant attention. However, applying MOF-based adsorbents in complex flavonoid separation scenarios remains challenging. In this study, we successfully synthesized adsorbent materials capable of efficiently adsorbing flavonoids using a vacuum freeze-drying method. The materials were derived from a cross-linked chitosan aerogel functionalized with amino-substituted zeolite imidazolium ester skeleton (ZIF-8). The ZIF-8-NH2, synthesized via in situ substitution of 2-aminobenzimidazole within the ZIF-8 framework, exhibits a smaller pore size than mono ligand ZIF-8. Due to its synergistic interaction with chitosan's biocompatibility and porous structure, the aerogel material (ZIF-8-NH2/CS) exhibited outstanding adsorption capacities (183.37 mg/g, 226.34 mg/g, and 187.16 mg/g) in standard solutions (T = 318 K, rpm = 200) of luteolin, quercetin, and rutin, along with high adsorption rates (71.3 ± 2.3 %, 72.4 ± 1.4 %, and 70.7 ± 3.5 %). And showed rapid adsorption in the first 60 min. After 5 cycles, the adsorption capacity of ZIF-8-NH2/CS aerogel remained at 80.5 % of the adsorption capacity of the initial cycle, and therefore, ZIF-8-NH2/CS aerogel has a good potential for reusability. Additionally, the adsorption process adhered to pseudo-first-order and pseudo-second-order kinetic models, alongside Langmuir and Freundlich isothermal adsorption models. This study introduces novel ideas and methods for the extraction and separation of flavonoids. Furthermore, the developed ZIF-8-NH2/CS aerogels with amino functionality hold promise for diverse applications in separating and purifying bioactive substances.

Investigation of the biological removal of nickel and copper ions from aqueous solutions using mixed microalgae

AbstractThe use of mixed microalgae offers an effective solution for the management of contamination risks in cultivation while enhancing economic viability. In this study, mixed microalgae were used for the first time for the removal of copper (Cu) and nickel (Ni) from aqueous solutions. The characteristics of the adsorbents were examined thoroughly, and the adsorption process was assessed using isotherms, kinetics, and thermodynamics. Particle size, concentration, contact time, temperature, and pH were among the variables assessed. The findings demonstrated that, at an initial concentration of 100 mg L–1 and a pH of 6, the maximum adsorption of Cu with a particle size of 1 mm (90.20%) took place in 60 min. The highest adsorption rate (78.25%) was found for Ni. Microalgae performed best over 180 min at room temperature and at pH values that promoted metal dissolution. The removal percentages of wet and dried microalgae were comparable, and the wet adsorbent was more economical. It was feasible to remove both metals at the same time. Up to three cycles of adsorbent reuse were possible, with sodium hydroxide treatment offering superior removal to hydrochloric acid. Thermodynamic analysis demonstrated that this process, which results in a disordered state, is exothermic and spontaneous.

The fate of Cd in Soils with Various Particle Sizes: Characteristics, Speciation Distribution and Influencing Factors.

This study investigated the distribution of Cd in soil water-stable aggregate particles of varying sizes, revealing that smaller particles have higher total Cd content as well as different forms of Cd content, with the clay particle showing a greater tendency to accumulate Cd. However, the proportion of high activity Cd is lower in clay particles, posing a lower environmental risk of Cd transformation compared to silt particles. Adsorption experiments indicated that the clay particle exhibits the strongest adsorption capacity and highest adsorption rate. Additionally, correlation and principal component analyses identified Fe-Mn oxides and organic matter as the primary influencing factors on Cd distribution characteristics, with pH playing a secondary role. These findings provide valuable insights for the remediation of heavy metal-contaminated soil.

Graphene aerogel with double pore structure for marine oil spill emergency response

Due to its high porosity, large specific surface area, and strong photothermal conversion performance, graphene aerogel has unique advantages in the field of pollution treatment, especially in the field of recovering highly viscous oils. However, for the treatment of highly viscous oils, the high adsorption capacity and high adsorption rate of graphene aerogel often cannot be combined, which is one of the important reasons limiting its development in this field. A double-step templating strategy for graphene aerogels preparation was used in this work, i.e., Pickering emulsion soft templating and unidirectional freeze casting. Specifically, the dense Pickering emulsion droplets can be stabilized in a short period of time, so that they can be cured quickly. After that, graphene aerogels (DGA-0.8-25) with dual pore structure were prepared by unidirectional freeze casting technology to further form aligned pores based on the pores formed by the Pickering emulsion droplet soft template. The dense presence of Pickering emulsion droplets gives DGA-0.8-25 an ultra-high porosity (96.8 %), which can adsorb 184.53 times its own mass of crude oil. Due to the unidirectional pore structure, the adsorption rate of DGA-0.8-25 on crude oil is as high as 8.39 g·g−1·min−1, which realizes dual improvement of the adsorption capacity and rate of graphene aerogel on crude oil and shows a good application prospect in the treatment of high viscosity crude oil. In addition, DGA-0.8-25 has unique advantages in the field of oil–water separation, with a separation efficiency of 99.04 % for water-in-oil emulsions and 97.63 % for oil-in-water emulsions. When repeated used in photothermal adsorption of highly viscous oil, DGA-0.8-25 can still maintain more than 90.61 % of its initial adsorption capacity after ten cycles of use-regeneration. Because of its unique advantages such as high efficiency and low cost, DGA shows promising in its future large-scale use.

Effects of cyanotoxins on nitrogen transformation in aquaculture systems with microplastics coexposure: Adsorption behavior, bacterial communities and functional genes

Microcystin-LR (MC-LR) and microplastics (MPs) have attracted increasing attention as important new pollutants in freshwater fishery environments. However, there are few reports on the effects of long-term combined MC-LR and MPs pollution on nitrogen transformation and microbial communities in aquaculture ponds, and the resulting risks have yet to be determined. Therefore, in this study, traditional refractory MPs (polystyrene, PS), biodegradable MPs (polylactic acid, PLA) and MC-LR, which are common in freshwater fishery environments in China, were selected as pollutants to construct a microcosm that simulates freshwater aquaculture ponds. MC-LR coexposure to PS and PLA was tested to reveal the effects of these pollutants on nitrogen transformation and microbial communities in aquaculture ponds, as well as to elucidate the potential risks posed by traditional refractory MPs and biodegradable MPs to freshwater aquaculture ecosystems. The results revealed that the MPs had a relatively high adsorption rate for MC-LR and that PS presented a relatively high adsorption capacity, whereas PLA presented a relatively high desorption capacity. Single or combined MPs and MC-LR pollution disrupted the normal nitrogen cycle in the aquaculture system, causing an overall loss of nitrogen in the water, and denitrification and nitrogen fixation in the water were inhibited to a certain extent through the inhibition of nitrogen cycle-related functional genes, with the PS + MC-LR group having the greatest inhibitory effect. In addition, compared with single-pollutant exposure, combined exposure to MC-LR and MPs had a greater effect on the microbial community composition. Analysis of the integrated biomarker response (IBR) index revealed that the risk of combined exposure to MC-LR and PS was greater than that of single exposure, so this phenomenon merits further attention.

Graphene oxide-polydopamine loaded uniform fibrous membranes via robust multi-channel microfluidic-electrospinning method

The rapid development of modern industries has caused serious water pollution such as dyes wastewater, which brings environmental problems and threatens human health. Thus, methods allowing efficient dyes removal from wastewater are substantially desirable. In this work, we fabricated graphene oxide-polydopamine (GO-PDA) by microfluidics, which enables rapid synthesis of products with excellent uniformity due to the precise control of reaction conditions. In addition, the GO-PDA/ thermoplastic polyurethane (GO-PDA/TPU) composite fibrous membrane was prepared in a high-efficiency manner by microfluidic electrospinning with a four-channel chip. Interestingly, GO-PDA not only improves the mechanical strength and hydrophilicity of the composite fibrous membrane, but also endows the membrane with efficient dye adsorption and separation capacity both for single and mixed dyes. It has been proved that the GO-PDA/TPU composite fibrous membrane exhibits selectivity towards cationic dyes, where the removal efficiency is up to 99 wt%. Moreover, the fibrous membrane could be utilized in a continuous and cyclic manner, which still maintains a high adsorption rate (>95 wt%) after 5 recycling, illustrating outstanding durability and reusability. This work proposes an efficient GO-PDA/TPU composite fibrous membrane towards selective adsorption of cationic dyes, which is of great significance in wastewater purification.

Preparation, Characterization, and Adsorption Performance of H2TiO3 Lithium Ion Sieves with Homogeneous Nanoparticles: Kinetics, Thermodynamics, and Mechanism Analysis

AbstractLi2TiO3 precursor with layered structure is successfully prepared by template‐free method using anatase TiO2 and Li2CO3, followed by the treatment of dilute hydrochloric acid, which leads to obtaining H2TiO3 lithium ion sieve nanoparticles with uniform dispersion and small size. The adsorption performance and mechanism of the H2TiO3 are being studied. The experimental results show that the H2TiO3 lithium ion sieve has a large BET specific surface area (19.10 m2 g−1) and good thermal stability. At the same time, it also has a high adsorption rate and adsorption capacity (55.13 mg g−1) towards Li+ in solution due to its high dispersibility and uniformity of particle size, which can expose more adsorption sites in LiCl solution. The adsorption capacity of the H2TiO3 lithium ion sieve can reach 46.63 mg g−1, which achieves 84.58% of the equilibrium adsorption capacity. The equilibrium adsorption parameters follow the Langmuir model perfectly, demonstrating that Li+ undergoes monolayer adsorption. The results of thermodynamic and kinetic analysis show that the adsorption behavior of H2TiO3 is spontaneous and conforms to the pseudo‐second‐order kinetic model, indicating the adsorption process is controlled by chemosorption. In addition, after five adsorption/desorption cycles, the H2TiO3 lithium ion sieve still shows a high adsorption capacity of 46.15 mg g−1, and the dissolution loss of titanium is only 0.14%, which shows that the cycle stability is excellent. XPS and zeta potential analyses illustrate that the adsorption mechanism of Li+ on the H2TiO3 is an ion exchange reaction between Li+ and H+, combined with the electrostatic attraction of the adsorbent surface. Additionally, the adsorption performance of H2TiO3 lithium ion sieve in West Taijinaier Salt Lake brine was tested, and the adsorbent material proves itself is a perspective candidate for lithium extraction from aqueous lithium resources.

Efficient removal of ammonia–nitrogen in wastewater by zeolite molecular sieves prepared from coal fly ash

Zeolite molecular sieves are potential adsorbents for wastewater treatment, characterized by high efficiency, simple process, easy regeneration, and low treatment cost. In this study, zeolite A molecular sieves were prepared using coal fly ash (CFA), which is an effective method for the utilization of CFA. The results showed that the CFA-based zeolite molecular sieves synthesized under optimized conditions exhibited excellent adsorption and removal rates (> 40%) for ammonia–nitrogen in wastewater of different concentrations and properties. The analysis of adsorption kinetics revealed that the adsorption process followed pseudo-second-order kinetics model, indicating that the adsorption of ammonia–nitrogen on zeolite is primarily controlled by chemisorption rather than physisorption. The adsorption process can be divided into two stages, with a higher adsorption rate and a smaller diffusion boundary layer thickness in the first stage, and a lower adsorption rate and an increased diffusion boundary layer thickness in the second stage. This indicates that as the adsorption proceeds, the internal diffusion resistance within the particles gradually increases, leading to a decrease in the adsorption rate until reaching equilibrium, where both the diffusion and adsorption become stable. The adsorption isotherms of ammonia–nitrogen on zeolite A conformed to the assumptions of the Langmuir model, suggesting that the adsorption mechanism primarily involves uniform monolayer adsorption on the surface without intermolecular interactions.

High-performance removal of methylene blue dye using porous lignin extracted from sugarcane bagasse by deep eutectic solvent

This study evaluated the ability of triethyl benzyl ammonium chloride/lactic acid deep eutectic solvent extracted lignin (TEBAC/LA-DES-L) to adsorb methylene blue (MB) without additional functional group modification. The structure and morphology of TEBAC/LA-DES-L were characterized using SEM, BET, FT-IR, and TGA techniques. Various factors influencing MB adsorption, such as extraction temperature, solution pH, adsorbent dose, initial MB concentration, adsorption time, and reaction temperature, were investigated. The Redlich-Peterson isotherm displayed a good fit for the experimental data, with a maximum adsorption capacity of 85.16 mg/g. Kinetic analysis suggested that the adsorption process followed the pseudo-second-order model, with adsorption occurring in <100 min on DES-L-4 h. The mechanism of MB adsorption on DES-L-4 h was attributed to electrostatic attraction, hydrophobic interactions, and hydrogen bonding forces. Overall, DES-L-4 h demonstrated high adsorption capacity and rapid adsorption rate, making it a promising adsorbent for effectively removing cationic dyes from wastewater.

Highly efficient malachite green adsorption by bacterial cellulose and bacterial cellulose/locust bean gum composite

In this study, bacterial cellulose (BC) and BC/locust bean gum (LBG) composite produced from banana hydrolysate were both used as the adsorbent for various organic dyes adsorption especially for malachite green (MG) adsorption for the first time. The BC/LBG(2%) composite exhibited significantly enhanced swelling rate and textural characteristics while maintained the basic structure of BC as depicted by XRD, FT-IR, and NMR, providing a foundation for its application as an excellent adsorbent. The composite exhibited a high adsorption rate and adsorption capacity for MG (exceeding 95 % and 2000 mg/g), and had a good selectivity for MG adsorption in the solution containing crystal violet (CV), rhodamine B (RB), and methyl orange (MO). The MG adsorption process conformed to multiple models including Langmuir and pseudo-first-order models. And the adsorption mechanism mainly comprised chemical adsorption (hydrogen bonding and electrostatic interactions) and physical adsorption. The reusability of BC/LBG(2%) composite was attractive for industrial application that the MG adsorption rate reduced merely a little (still higher than 88 %) after the 5th regeneration process. Overall, considering its adsorption capacity, selectivity, and reusability, BC/LBG(2%) composite prepared by in-situ fermentation with LBG addition was a competent adsorbent for MG adsorption and MG containing wastewater treatment.

Porous sodium alginate/cellulose nanofiber composite hydrogel microspheres for heavy metal removal in wastewater

High adsorption capacity, high adsorption rate and reusable adsorbents are urgent needed for removing heavy metals from wastewater. In this study, porous sodium alginate/cellulose nanofiber (SA/CNF) composite hydrogel microspheres were prepared by combining sodium alginate with cellulose nanofibers by microfluidics technology and adding polyethylene glycol (PEG) as pore making agent. The SA/CNF composite hydrogel microspheres could efficiently adsorb heavy metals (Pb2+, Cu2+ and Cd2+) in wastewater. The influencing factors of adsorption process, including pH, temperature, initial concentration, coexisting ions and aquatic environments, were systematically discussed. The adsorption process was more consistent with Langmuir isotherm model and pseudo-second-order model in batch system, indicating the adsorption process was mainly chemical adsorption. The adsorption capacity to Pb2+ obtained by Langmuir model was as high as 544.66 mg/g at 20 °C. Fixed-bed column adsorption experiments demonstrated the excellent performance of the as-prepared SA/CNF microspheres for treatment of the flowing wastewater in a column system. Overall, a highly practical adsorption process based on hydrogel adsorbents was developed for the removal of heavy metals from actual wastewater.

Removal of PFOA from water by activated carbon adsorption: Influence of pore structure

Activated carbon (AC) adsorption is a practical process for the removal of perfluorooctanoic acid (PFOA) in aquatic environments, but the relationship between its pore structure and adsorption performance is not well understood. In this study, the KOH-activated carbons (KACs) with different tailored pore structures were prepared, and presented a 2.61-fold higher adsorption capacity and a 2.21-fold higher adsorption rate than the raw AC. An in situ characterization method and a modified adsorption model were introduced to investigate the impact of pore size, which demonstrated that the ultra-micropores (<1.2 nm) and small mesopores (2.0–3.0 nm) contributed significantly to the adsorption of PFOA, with the highest mean contribution factor (k) of 0.45 and the second highest of 0.39, respectively. Molecular dynamics simulations revealed that PFOA molecules tend to attach to the pore walls at various pore sizes. The adsorption of PFOA in the ultra-micropores was dominated by enhanced interactions due to the overlapping potentials of the bilateral pore walls (maximum of −567.32 Kcal·mol−1) and hydrophobic interactions. PFOA micelles or hemi-micelles could be formed in the small mesopores, allowing them to function as both the molecule transportation channels and strong adsorption sites. This study would guide the development of activated carbon tailored for the selective adsorption of PFOA from water.

Biomimetic mineralization synthesis of tricobalt tetraoxide/nitrogen doped carbon skeleton for enhanced capacitive deionization

Developing novel capacitive deionization (CDI) electrode materials with high salt adsorption capacity and adsorption rate is essential for desalination applications, however, encountering significant challenges. Herein, a facile and energy economical biomimetic mineralization method is proposed to construct the tricobalt tetraoxide/nitrogen doped carbon (Co3O4/NC) heterostructure. Benefiting from the mild biomimetic mineralization process, small Co3O4 nanoparticles grow uniformly on interconnected multi-branched NC skeleton. The as-obtained Co3O4/NC heterostructure exhibits a salt adsorption capacity of 44.5 mg g−1, adsorption rate of 7.9 mg g−1 min−1, and 91.3 % of capacity retention after 60 cycles at 1.2 V in 500 mg L−1 salt solution. These performances overwhelm the bare Co3O4 (24.6 mg g−1, 3.5 mg g−1 min−1, 65.7 %), indicating superior desalination performances of the Co3O4/NC heterostructure. This study gives an insight into the biomimetic mineralization method and provides one promising candidate of CDI electrode.

Prebiotic stachyose inhibits PRDX5 activity and castration-resistant prostate cancer development

Stachyose (STA) is a prebiotic with poor oral bioavailability. In this study, we developed stachyose caproate (C6-STA), as a novel STA derivative, to demonstrate its high adsorption rate via oral administration. Pharmacokinetic analysis reveals that after absorption, the STA derived from C6-STA reaches its highest peak in the blood, liver, and kidney at 20 min, 30 min, and 12–24 h, with approximate levels of 1200 μg/mL, 0.14 μg/mL, and 0.2–0.3 μg/mL, respectively. In addition, the accumulation of STA in prostate tissues of mice with castration-resistant prostate cancer (CRPC) (1.75 μg/mg) is 10-fold higher than that in normal prostate tissues (0.14 μg/mg). The analysis also reveals that C6-STA has t1/2 of 12.8 h and Tmax of 0.25 h, indicating that it has the potential to be used as a promising drug in clinical practice. The toxicological evaluation shows no obvious side effects of C6-STA in mice administered with a 0.2 g/kg intragastric dose. Pharmacodynamic analysis and mechanism investigation of C6-STA show its ability to inhibit peroxiredoxin 5 (PRDX5) enzyme activity, disrupt PRDX5-nuclear factor erythroid 2-related factor 2 (NRF2) interaction, and decrease NAD(P)H quinone dehydrogenase 1 (NQO1) levels. NQO1 decrease further causes the accumulation of quinone radicals, which ultimately leads to the apoptosis of LNCaP cell-derived drug-tolerant persister (DTP) cells and slows CRPC progression. Our study discovered the anti-tumor activity of stachyose and shows that prebiotics have biological functions in vivo besides in the gut. Further investigation of C6-STA, especially in CRPC patients, is warranted.

Electron-rich COFs with a bis-triphenylamine structure as the main chain: Ultrafast and ultrahigh iodine capture

The construction of ideal adsorbents for the capture of radioiodine usually requires high adsorption capacity and high adsorption rate. However, this is still a challenging problem. The advantages of COFs based on their good crystallinity, pore order, and structural diversity make COFs ideal adsorbents. Here, we developed three novel electron-rich COFs based on the triphenylamine, which have good chemical, thermal, and radiation-resistant stability and are suitable for the harsh environment of radioactive iodine therapy. Upon the introduction of heteroatom N/S, TAPD-PDB and TAPD-TDB exhibited amazing adsorption capacities (75 °C: 7.88 g g−1 and 6.98 g g−1, 25 °C: 4.46 g g−1 and 3.62 g g−1), while the adsorption rates, K80%, are significantly increased to 5.34 g g−1h−1 and 4.22 g g−1h−1, which is higher than most of the reported iodine adsorbents. It was surprising that COFs also have excellent adsorption properties for iodine in cyclohexane solution up to 1260 mg L−1. FT-IR, XPS, Raman and electrostatic potential calculations indicate that the ultrafast and ultrahigh iodine uptake of COFs can be attributed to the interplay of their rich electronic structure, efficient adsorption sites, helical conformation and charge transfer. This study shows the efficient and ultrafast removal of iodine from nuclear wastewater and nuclear exhaust gas by electron-rich COFs.

Surface functionalization of oil palm empty fruit bunch (OPEFB)-derived cellulose as a carboxyl platform for metal cations and dyes removal from aquatic media

The abundant oil palm empty fruit bunch (OPEFB) as by-product of palm oil milling processes exhibits a potential as an alternative cellulose feedstock for bio-adsorbent. This study aimed to produce a highly carboxylated bio-adsorbent for direct industrial application from OPEFB-based cellulose via mercerization and followed by esterification with succinic anhydride (SA) to enhance its adsorptive capability towards hazardous heavy metal and dyes ions. The modification using SA provides the carbon backbone platform for carboxyl group attachment for the contaminants. The results showed that the carboxylated cellulose had a high carboxyl content (4.39 mmol/g). Carboxylated cellulose had a higher binding capacity for adsorbates, with removal rates of 94.7%, 97.85%, 40.9%, and 90.15% for dye, Pb2+, Cu2+, and Cd2+ cations, respectively, at pH 6, 4 hours reaction time, and at room temperature. In comparison, unmodified cellulose removed only 47%, 23.1%, 2.9%, and 7.5% for dye, Pb2+, Cu2+, and Cd2+ cations, respectively. The adsorption kinetics study revealed that the adsorption process followed the pseudo-second-order model. The adsorption isotherm of these two metal cations follows the model of Langmuir very well, while Cu2+ follows the Freundlich model. Our method produces bio-adsorbents with high carboxyl content and adsorption rate in a short reaction time using OPEFB as a green precursor material that is easily scalable for industrial use.

Fabrication of magnetic ferroferric oxide-based composite for efficiently removing and recycling ciprofloxacin

The extensive use of antibiotics and recklessly discarding have caused serious water pollution. Its controlling and remedying become an urgent problem. With the goal of removing ciprofloxacin hydrochloride (HCIP), a magnetic adsorbent of Fe3O4@Mg(OH)2 was prepared via a facile approach in this work. The structure and morphology were systematically characterized by XRD, SEM, FT-IR and XPS. It is found hexagonal Mg(OH)2 flakes are evenly coating on the surface of Fe3O4. This structured morphology offers Fe3O4@Mg(OH)2 high specify surface area. The composite shows excellent removal performance. It achieves almost 99 % HCIP elimination within 1.5 h. The influence of the dosage of adsorbents, pH and interfering ions and reusability were fully studied. It is shown that the composite can be used in neutral condition and has long serve life. The cost effective synthesis, simple operation, high adsorption rate and long serve life make Fe3O4@Mg(OH)2 wide application for water treatment in a large scale.

Constructing 2D Polyphenols-Based Crosslinked Networks for Ultrafast and Selective Uranium Extraction from Seawater.

The role of tannins (TA), a well-known abundant and ecologically friendly chelating ligand, in metal capture has long been studied. Different kinds of TA-containing adsorbents are synthesized for uranium capture, while most adsorbents suffer from unfavorable adsorption kinetics. Herein, the design and preparation of a TA-containing 2D crosslinked network adsorbent (TANP) is reported. The ≈1.8-nanometer-thick TANP films curl up into micrometer-scale pores, which contribute to fast mass transfer and full exposure of active sites. The coordination environment of uranyl (UO2 2+) ions is explored by integrated analysis of U L3-edge XANES and EXAFS. Density functional theory calculations indicate the energetically favorable UO2 2+ binding. Consequently, TANP with excellent adsorption kinetics presents a high uranium capture capacity (14.62mg-Ug-Ads-1) and a high adsorption rate (0.97mgg-1day-1) together with excellent selectivity and biofouling resistance. Life cycle assessment and cost analysis demonstrate that TANP has tremendous potential for application in industrial-scale uranium extraction from seawater.

A Review of Life Cycle Assessment of Nanomaterials-Based Adsorbent for Environmental Remediation

&lt;p&gt;Nanomaterials, known for their exceptional physicochemical properties, are used in electronics, skincare, catalysts, agriculture, and water treatment. Their small size and large surface area enable high adsorption capacities and rapid adsorption rates, effectively removing organic and inorganic pollutants from water. Designed as composites, nanomaterials enhance adsorption capacity, improve mechanical strength, and provide support matrices for retaining nanoparticles. Nanoadsorbents are particularly effective in removing toxic metals from wastewater and drinking water, targeting low concentrations of metals like arsenic, cadmium, lead, and mercury, crucial given stringent discharge regulations. However, the widespread use of nanomaterials poses potential health and environmental risks, as their production involves significant energy and material inputs, generating pollutants. Most research focuses on functionalities without considering life cycle environmental impacts. Life cycle assessment (LCA) is a comprehensive tool for evaluating these impacts, assessing products from cradle to grave, including raw material extraction, processing, manufacturing, distribution, use, maintenance, and disposal or recycling. LCA, based on the ISO 14040 series, includes four phases: goal and scope definition, life cycle inventory, life cycle impact assessment, and life cycle interpretation. This study categorizes existing research based on the four LCA phases, aiming to highlight current practices, challenges, and progress. The findings provide insights and recommendations for future research to ensure the sustainable development of nanomaterials.&lt;/p&gt;