Exceptional Capture Research Articles

Great truths are always simple: A millimeter-sized macroscopic lanthanum-calcium dual crosslinked carboxymethyl chitosan aerogel bead as a promising adsorbent for scavenging oxytetracycline from wastewater

Given their increasing environmental and health harms, it is crucial to develop green and sustainable techniques for scavenging antibiotics represented by oxytetracycline (OTC) from wastewater. In the present work, a structurally simple lanthanum-calcium dual crosslinked carboxymethyl chitosan (CMCS-La3+-Ca2+) aerogel was innovatively synthesized for adsorptive removal of OTC. It was found that CMCS and La3+ sites collaboratively participated in OTC elimination, and OTC removal peaked over the wide pH range of 4–7. The process of OTC sorption was better described by the pseudo-second-order kinetic model and Redlich-Peterson model, and the saturated uptake amount toward OTC was up to 580.91 mg/g at 303 K, which was comparable to the bulk of previous records. The as-fabricated composite also exerted exceptional capture capacity toward OTC in consecutive adsorption-desorption runs and high-salinity wastewater. Amazingly, its packed column continuously ran for over 60 h with a dynamic uptake amount of 215.21 mg/g until the adsorption was saturated, illustrating its great potential in scale-up applications. Mechanism studies demonstrated that multifarious spatially-isolated reactive sites of CMCS-La3+-Ca2+ cooperatively involved in OTC capture via multi-mechanisms, such as n-π EDA interaction, H-bonding, La3+-complexation, and cation-π bonding. All the above superiorities endow it as a promising adsorbent for OTC-containing wastewater decontamination.

High catalytic nickel−platinum nanozyme enhancing colorimetric detection of Salmonella Typhimurium in milk

Colorimetric qualitative and sensitive quantitative detection of Salmonella Typhimurium (S. Typhimurium) holds significant importance for ensuring food safety and preventing foodborne illnesses. In the study, an ultra-high catalytic activity and biocompatible nickel-platinum nanoparticle (NiPt NP) nanozyme is successful synthesized to prepare a NLISA strategy for the detection of S. Typhimurium. The synthesized NiPt NPs exhibit high oxidase-like catalytic efficiency, with a Michaelis constant (Km) of 0.493 mM, similar to that of natural horseradish peroxidase (HRP). The maximal reaction velocity (Vmax) was determined to be 1.97 × 10-7 M·s-1 exhibiting a 1.97-fold higher than that of the HRP (1.0 × 10-7 M·s-1). Meanwhile, the antibody employed in this NiPt NPs-based NLISA exhibits exceptional capture efficacy, generating a stable immune complex with S. Typhimurium. The NiPt NPs-based NLISA demonstrates sensitivity, specificity, convenience, and cost-efficiency for the detection of S. Typhimurium. Under optimal conditions, this NiPt NPs-based NLISA demonstrates a quantitative range of 103∼106 cfu/mL with a detection limit as low as 103 cfu/mL. A single-blind experimental testing detects different concentrations of S. Typhimurium spiked skim milk, indicating the application potential of the proposed NLISA in real samples. In all, this research provides novel insights into the synthesis of nanozymes with excellent catalytic activity and their applications in S. Typhimurium biosensing.

Biomass waste-assisted micro(nano)plastics capture, utilization, and storage for sustainable water remediation

Micro(nano)plastics (MNPs) have become a significant environmental concern due to their widespread presence in the biosphere and potential harm to ecosystems and human health. Here, we propose for the first time a MNPs capture, utilization, and storage (PCUS) concept to achieve MNPs remediation from water while meeting economically productive upcycling and environmentally sustainable plastic waste management. A highly efficient capturing material derived from surface-modified woody biomass waste (M-Basswood) is developed to remove a broad spectrum of multidimensional and compositional MNPs from water. The M-Basswood delivered a high and stable capture efficiency of >99.1% at different pH or salinity levels. This exceptional capture performance is driven by multiscale interactions between M-Basswood and MNPs, involving physical trapping, strong electrostatic attractions, and triggered MNPs cluster-like aggregation sedimentation. Additionally, the invivo biodistribution of MNPs shows low ingestion and accumulation of MNPs in the mice organs. After MNPs remediation from water, the M-Basswood, together with captured MNPs, is further processed into a high-performance composite board product where MNPs serve as the glue for utilization and storage. Furthermore, the life cycle assessment (LCA) and techno-economic analysis (TEA) results demonstrate the environmental friendliness and economic viability of our proposed full-chain PCUS strategy, promising to drive positive change in plastic pollution and foster a circular economy.

Ultrafast Removal of Thorium and Uranium from Radioactive Waste and Groundwater Using Highly Efficient and Radiation-Resistant Functionalized Triptycene-Based Porous Organic Polymers.

Thorium (Th) and uranium (U) are important strategic resources in nuclear energy-based heavy industries such as energy and defense sectors that also generate significant radioactive waste in the process. The management of nuclear waste is therefore of paramount importance. Contamination of groundwater/surface water by Th/U is increasing at an alarming rate in certain geographical locations. This necessitates the development of strategic adsorbent materials with improved performance for capturing Th/U species from radioactive waste and groundwater. This report describes the design of a unique, robust, and radiation-resistant porous organic polymer (POP: TP-POP-SO3NH4), which demonstrates ultrafast removal of Th(IV) (<30 s)/U(VI) (<60 s) species present in simulated radioactive wastewater/groundwater samples. Thermal, chemical, and radiation stabilities of these POPs were studied in detail. The synthesized ammoniated POP revealed exceptional capture efficiency for trace-level Th (<4 ppb) and U (<3 ppb) metal ions through the cation-exchange mechanism. TP-POP-SO3NH4 shows a significant sorption capacity [Th (787 mg/g) and U (854 mg/g)] with an exceptionally high distribution coefficient (Kd) of 107 mL/g for Th. This work also demonstrates a facile protocol to convert a nonperforming POP, by simple chemical modifications, into a superfast adsorbent for efficient uptake/removal of U/Th.

Low-resistance and high-tolerance monolithic spiro-bifluorene-based conjugated microporous polymer for co-capture of PM and CO2 in waste gas

The utilization of solid adsorbents for the co-capture of harmful particulate matter (PM) and carbon dioxide (CO2) in industrial exhaust streams represents a crucial component within the emerging field of waste gas terminal treatment technologies. Extensive research has focused on particulate or powdered adsorbents rather than monolithic materials, whereas monolithic adsorbents exhibit superior advantages in practical industrial applications. Herein, a monolithic spiro-bifluorene-based conjugated micro-porous polymer (DS-CMPs) with hierarchical porous and functionalized hollow nanotube structures was proposed. The favorable characteristics exhibited by DS-CMPs encompass a highly delocalized π-π conjugated skeleton, permanent porosity, unique thermal and chemical stability, precisely defined chemical composition, and excellent water vapor tolerance. These inherent qualities guarantee that DS-CMPs employed for the co-capture of PM and CO2 from exhaust gases exhibit exceptional capture efficiency, low permeation resistance, favorable isosteric heat of adsorption (Qst), and recyclability. The reasons behind the high capture efficiency and low permeation resistance of monolithic DS-CMPs were analyzed through mechanistic exploration and Electrostatic Surface Potential (ESP) calculations. Moreover, the stability inherent in the framework structure and physicochemical properties of DS-CMPs can surmount the notable decline in the capturing capability of porous materials utilized within damp and elevated temperature surroundings. Following exposure to elevated humidity (RH = 86 ± 1 %) and high-temperature (500 ℃) conditions, DS-CMPs exhibited a remarkable capture efficiency exceeding 99.00 % for PM2.5. The self-assembly of monolithic DS-CMPs into a smooth array of nanotube bundles effectively reduces the friction between airflow and material, enhances airflow dispersion, and achieves a minimum permeability resistance of only 8 Pa. At a pressure of 1 bar and temperature of 273 K, the CO2 adsorption capacity of DS-CMPs amounts to 2.72 mmol/g. The high absorption capacity for CO2 is primarily attributed to the presence of a significant microporous/mesoporous ratio and notable surface charge differences. In contrast to powdered adsorbents plagued by sample elution and gas pressure drop issues, the monolithic DS-CMPs showcases good mechanical properties, rendering them readily applicable within industrial bed circulation systems to achieve the co-capture of PM and CO2.

Exceptional capture of methane at low pressure by an iron-based metal-organic framework.

The selective capture of methane (CH4) at low concentrations and its separation from N2 are extremely challenging owing to the weak host-guest interactions between CH4 molecules and any sorbent material. Here, we report the exceptional adsorption of CH4 at low pressure and the efficient separation of CH4/N2 by MFM-300(Fe). MFM-300(Fe) shows a very high uptake for CH4 of 0.85 mmol g-1 at 1 mbar and 298 K and a record CH4/N2 selectivity of 45 for porous solids, representing a new benchmark for CH4 capture and CH4/N2 separation. The excellent separation of CH4/N2 by MFM-300(Fe) has been confirmed by dynamic breakthrough experiments. In situ neutron powder diffraction, and solid-state nuclear magnetic resonance and diffuse reflectance infrared Fourier transform spectroscopies, coupled with modelling, reveal a unique and strong binding of CH4 molecules involving Fe-OH⋯CH4 and C⋯phenyl ring interactions within the pores of MFM-300(Fe), thus promoting the exceptional adsorption of CH4 at low pressure.

PH dependent separation of uranium by chelation chromatography using pyridine 2,6-dimethanol as a chelator: Single crystal X-ray structural confirmation of the chelated uranium complex

A very effective sorbent material which exhibits exceptional capture of hexavalent uranium from other actinides and lanthanides at μg g −1 level, features pyridine 2,6-dimethanol immobilized onto alumina. The maximum sorption capacity for dioxouranium(VI) was found as 1.96 mmol g −1 at pH 3.0. The adsorbed uranium complex was eluted completely by 0.05 mol L −1 (NH 4) 2CO 3 solution and the concentration of hexavalent dioxouranium ion was monitored spectrophotometrically using Arsenazo III. The structure of the chelated uranium complex has been confirmed by single crystal X-ray structure analysis and Fourier transform infrared red (FTIR) spectroscopy. Thermo gravimetric analysis/differential thermo gravimetric analysis (TGA/DTG) of the chelated uranium complex was performed. The method is reproducible with a relative standard deviation (RSD) of 1.2% ( N = 10) and the three sigma detection limits ( N = 15) 1.2 μg mL −1 respectively. A pre-concentration factor, almost 500, for uranium was achieved. Interferences from Th 4+, Mn 2+, Ni 2+ and Cu 2+ ions were masked with ethylene diamine tetra acetic acid (di-sodium salt) (Na 2EDTA) in the aqueous phase. The developed method has been tested for uranium recovery and estimation in some certified reference materials and environmental samples.