Molecular adsorbant

In recent years, the quest for an efficient and sustainable adsorbent material that can effectively remove harmful and hazardous dyes from industrial effluent has become more intense. The goal is to explore the capability of thermally modified nanocrystalline snail shells (TMNSS) as a new biosorbent for removing methylene blue (MB) dye from contaminated wastewater. TMNSS was employed in batch adsorption experiments to remove MB dye from its solutions, taking into account various adsorption parameters such as contact time, temperature, pH, adsorbent dosage, and initial concentration...

Metal-Organic Frameworks can be grafted with amines by coordination to metal vacancies to create amine-appended solid adsorbents, which are being considered as an alternative to using aqueous amine solutions for CO2 capture. In this study, we propose an alternative mechanism that does not rely on the use of neutral metal vacancies as binding sites but is enabled by the structural adaptability of heterobimetallic Ti2Ca2 clusters. The combination of hard (Ti+4) and soft (Ca2+) metal centers in the inorganic nodes of the framework enables MUV-10 to adapt its pore windows to the presence of triethylenetetramine molecules...

Silver (9 wt.%) was loaded on Co3 O4 -nanofiber using reduction and impregnation methods, respectively. Due to the stronger electronegativity of silver, the ratios of surface Co3+ /Co2+ on Ag/Co3 O4 were higher than on Co3 O4 , which further led to more adsorbed oxygen species as a result of the charge compensation. Moreover, the introducing of silver also obviously improved the reducibility of Co3 O4 . Hence the Ag/Co3 O4 showed better catalytic performance than Co3 O4 in benzene oxidation. Compared with the Ag/Co3 O4 synthesized via impregnation method, the one prepared using reduction method (named as AgCo-R) exhibited higher contents of surface Co3+ and adsorbed oxygen species, stronger reducibility, as well as more active surface lattice oxygen species...

To overcome the global water shortage, the treated wastewater is increasingly utilized in agricultural irrigation, and thus reducing freshwater consumption and increasing the water sustainability. Drip irrigation technology is the most appropriate irrigation method to utilize these water sources. However, its operating performance is negatively affected by calcium carbonate (CaCO3 ) scaling, which is one of the most dominant precipitations and also closely related to dissolved ions and the hydraulic characteristics inside irrigation systems...

The concurrent utilization of an adsorbent and absorbent for carbon dioxide (CO2 ) adsorption with synergistic effects presents a promising technique for CO2 capture. Here, 1-butyl-3-methylimidazole acetate ([Bmim][Ac]), with a high affinity for CO2 , and the molecular sieve SAPO-34 were selected. The impregnation method was used to composite the hybrid samples of [Bmim][Ac]/SAPO-34, and the pore structure and surface property of prepared samples were characterized. The quantity and kinetics of the sorbed CO2 for loaded samples were measured using thermogravimetric analysis...

Nanoparticle organic hybrid materials (NOHMs) have been proposed as excellent electrolytes for combined CO2 capture and electrochemical conversion due to their conductive nature and chemical tunability. However, CO2 capture behavior and transport properties of these electrolytes after CO2 capture have not yet been studied. Here, we use a variety of nuclear magnetic resonance (NMR) techniques to explore the carbon speciation and transport properties of branched polyethylenimine (PEI) and PEI-grafted silica nanoparticles (denoted as NOHM-I-PEI) after CO2 capture...

Shikimic acid (SA) is one of the most effective drugs against the A (H1N1) virus and has high medicinal value. Additionally, it has the ability to generate non-toxic herbicides and antimicrobial medications. The extraction from plants has proven to be the main route of production of SA with economic benefits and environmental efficiency. Therefore, it is necessary to perform purification of SA from these herbal medicines before quantifying it. In this study, researchers employed a boronate affinity-based controlled oriented surface imprinting technique to produce molecularly imprinted polymers (MIPs) as highly effective solid phase extraction (SPE) adsorbents for the isolation and purification of SA...

CONTEXT: To unravel the effects of the C vacancy, doping N type and number, the adsorption of HCHO and O2 was investigated on the graphene (Gr)-based supported Pt single atom by density functional theory calculations. The electronegativity of the vacancy and N-doped Gr was a crucial factor both for the anchoring for a Pt and the further adsorption of HCHO and O2 on the supported Pt. The electronegativity can be tuned by the C vacancy number (1V and 2V), the doping N type (graphitic-N, pyridinic-N and pyrrolic-N) and the doping pyridinic-N number (1N ~ 4N)...

Using knowledge from statistical thermodynamics and crystallography, we develop an image-image translation model, called SorbIIT, that uses three-dimensional grids of adsorbate-adsorbent interaction energies as input to predict the spatially resolved loading surface of nanoporous materials over a broad range of temperatures and pressures. SorbIIT consists of a closed-form differential model for loading-surface prediction and a U-Net to generate spatial differential distributions from the energy grids. SorbIIT is trained using the energy grids and adsorbate distributions (obtained from high-throughput simulations) of 50 synthesized and 70 hypothetical zeolites and applied for predicting the adsorption of carbon dioxide, hydrogen sulfide, n -butane, 2-methylpropane, krypton, and xenon in other zeolites from 256 to 400 K...

Due to the superior catalytic activity and efficient utilization of noble metals, nanocatalysts are extensively used in the modern industrial production of chemicals. The surface structures of these materials are significantly influenced by reactive adsorbates, leading to dynamic behavior under experimental conditions. The dynamic nature poses significant challenges in studying the  structure-activity relations of catalysts. Herein, we unveil an anomalous entropic effect on catalysis via surface pre-melting of nanoclusters through machine learning accelerated molecular dynamics and free energy calculation...

Three-dimensional sponge-architecture covalent organic frameworks (COFs)-aerogel was successfully designed and synthesized via a freeze-drying template approach, and utilized as an efficient sorbent in solid-phase extraction (SPE). A method for selective enrichment of pharmaceutical contaminants including tetracycline, chlortetracycline, methacycline and oxytetracycline in the environment and food samples was proposed by combining with high performance liquid chromatography (HPLC). To understand the adsorption mechanism, selectivity test and molecular dynamics (MD) simulated calculation were both carried out...

The global and local minimum configurations of single Hf atom doped Sn clusters are conducted via density function theory (DFT) combined with artificial bee colony algorithm (ABCluster). Furthermore, DFT method is also used to systematically investigate on their structural growth evolution, spectral and electronic information, thermochemical properties following the size of tin clusters doped Hf atom. Structurally, the ground-state geometries of neutral, anion and di-anion are discovered that, from n = 4, the number of Sn atoms in cluster, HfSnn 0/- /2- adsorb additional Sn atom on the prior architecture one by one until forming n = 17 for HfSnn -1 0/- , as well as forming n = 16 for HfSnn -1 2- ...

Heterogeneous catalytic systems with water as the solvent often have the disadvantage of cross-contamination, while concerns about the purification and workup of the aqueous phase after reactions are rare in the lab or industry. In this context, designing and developing the functional selective solid adsorbent and revealing the adsorption mechanism can provide a new strategy and guidelines for constructing supported heterogeneous catalysts to address these issues. Herein, we report the stable composite adsorbent (Fe/ATP@PPy: magnetic Fe3 O4 /attapulgite with the polypyrrole shell) that features an integrated multifunctional surface, which can effectively tune the selective adsorption processes for Cu2+ , Co2+ , and Ni2+ ions and nitrobenzene via the cooperative chemisorption/physisorption in an aqueous system...

n-C4H10 and iso-C4H10 are both important petrochemical raw materials. Considering the coexistence of the isomers in the production process, it is necessary to achieve their efficient separation through an economical way. However, to obtain high-purity n-C4H10 and iso-C4H10 in one-step separation process, developing iso-C4H10-exclusion adsorbents with high n-C4H10 adsorption capacity is crucial. Herein, we report a cage-like MOF (SIFSIX-Cu-TPA) with small windows and large cavities which can selectively allow smaller n-C4H10 enter the pore and accommodate a large amount of n-C4H10 simultaneously...

Halocarbons have important industrial applications, however they contribute to global warming and the fact that they can cause ozone depletion. Hence, the techniques that can capture and recover the used halocarbons with energy efficiency methods have recently received greater attention. In this contribution, we report the capture of dichlorodifluoromethane (R12), which has high global warming and ozone depletion potential, using covalent organic polymers (COPs). The defect-engineered COPs were synthesized and demonstrated outstanding sorption capacities, ~226 wt% of R12 combined with linear-shaped adsorption isotherms...

Drought is a global environmental problem, while the effect of drought-induced unsaturation on the fate of heavy metal ions is still poorly understood, particularly the lack of mechanistic information at the molecular level. This study used molecular dynamics simulations to investigate nanoscale interactions at the montmorillonite surface under different moisture conditions. Compared to the saturated condition, drought increased the amounts and strength of Cd2+ ions adsorbed on the montmorillonite (MMT) surface while decreased the diffusivity, which was especially obvious in extreme drought conditions (θv =21%-7%)...

Applying organic fertilizer is the main way to enhance soil fertility through the interfacial reaction between mineral and dissolved organic matter (DOM). However, the interfacial reaction between minerals and DOM may influence antimony(V) (Sb(V)) mobility in agricultural soils around antimony mines. In our study the ferrihydrite (Fh) was chosen as a representative mineral, to reveal the effect of its interaction with chicken manure organic fertilizer (CM-DOM) with Fh on Sb(V) migration. In this study, we investigated different organic matter molecular weights and C/Fe molar ratios...

A molecularly-imprinted electrochemiluminescence sensor was constructed for the determination of fenpropathrin (FPT) by molecular imprinting technology. In this sensing platform, the introduction of CdS@MWCNTs significantly enhanced the initial ECL signal of the luminol-O2 system. Specifically, MWCNTs was used as a carrier to adsorb more CdS, in which CdS acted as a co-reaction promoter for luminescence. Molecularly imprinted polymer (MIP) containing specific recognition sites of FPT was used as the material for selective recognition...

A porous geopolymer was synthesized using steel slag (accounting for 71.6 wt %) with the aim of effectively removing Cu2+ ions. The chemical composition and microstructure of this material were investigated using X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscope analysis, and BET method. The effects of H2 O2 doping, H2 O doping, and the curing temperature on the properties of this porous geopolymer were systematically investigated. Subsequently, the adsorption behavior of the porous geopolymer toward Cu2+ was explored through static adsorption experiments...

Borazine is a well-established precursor molecule for the growth of hexagonal boron nitride (h-BN) via chemical vapor deposition on metal substrates. To understand the formation of the h-BN/Rh(111) moiré from borazine on a molecular level, we investigated the low-temperature adsorption and thermally induced on-surface reaction of borazine on Rh(111) in situ using synchrotron radiation-based high-resolution x-ray photoelectron spectroscopy (XPS), temperature-programmed XPS, and near-edge x-ray absorption fine structure measurements...