Competitive Adsorption Research Articles

Study on the mechanism of competitive adsorption on the surface of potassium carbonate during direct air capture process

Study on the mechanism of competitive adsorption on the surface of potassium carbonate during direct air capture process

Competitive adsorption and strain modulation induced by low electronegative elements to improve phosphate tolerance in HT-PEMFC.

Competitive adsorption and strain modulation induced by low electronegative elements to improve phosphate tolerance in HT-PEMFC.

Competitive adsorption and diffusion of methane and vapor-phase per- and polyfluoroalkyl substances in montmorillonite nano pores: Environmental implications.

Competitive adsorption and diffusion of methane and vapor-phase per- and polyfluoroalkyl substances in montmorillonite nano pores: Environmental implications.

Role of Cr(VI) in the efficient removal of Cd(II) from aqueous solutions using Fe3S4 in a Cd(II)/Cr(VI) binary system.

Role of Cr(VI) in the efficient removal of Cd(II) from aqueous solutions using Fe3S4 in a Cd(II)/Cr(VI) binary system.

Application of heterogeneous Fenton-like reaction with modified zeolite for removal of antibiotics, antibiotic-resistant bacteria, and antibiotic-resistant genes from swine farm wastewater.

Application of heterogeneous Fenton-like reaction with modified zeolite for removal of antibiotics, antibiotic-resistant bacteria, and antibiotic-resistant genes from swine farm wastewater.

In situ high-resolution insights into the dynamics of arsenic (As) species and heavy metals across the sediment-water interface in a deep karst reservoir.

In situ high-resolution insights into the dynamics of arsenic (As) species and heavy metals across the sediment-water interface in a deep karst reservoir.

Effect of partial replacement of crystalline fat with peanut oleosome and polyglycerol polyricinoleate on aerated emulsion.

Effect of partial replacement of crystalline fat with peanut oleosome and polyglycerol polyricinoleate on aerated emulsion.

Experimental study on the CH4/CO2 competitive adsorption behaviors of typical shale minerals in low pressure reservoirs

Experimental study on the CH4/CO2 competitive adsorption behaviors of typical shale minerals in low pressure reservoirs

Spectroscopically study of competitive adsorption of planer and non-planer reactive dyes over magnesium oxide nanoparticles sustainably fabricated through autoignition

Spectroscopically study of competitive adsorption of planer and non-planer reactive dyes over magnesium oxide nanoparticles sustainably fabricated through autoignition

Unraveling the promotion for SO2 and H2O resistance of transition metal-doped CeO2-TiO2 catalysts in NH3-SCR reaction: A DFT study.

Unraveling the promotion for SO2 and H2O resistance of transition metal-doped CeO2-TiO2 catalysts in NH3-SCR reaction: A DFT study.

Hydrothermal pretreatment of lignin-derived activated carbon for enhanced competitive adsorption of benzene and NO: Mechanistic insights from DFT simulations

Hydrothermal pretreatment of lignin-derived activated carbon for enhanced competitive adsorption of benzene and NO: Mechanistic insights from DFT simulations

The Regulation Mechanism of Oxygen Vacancies in Ruddlesden-Popper Perovskite Ln2NiO4 (Ln = La, Pr, Nd) Air Electrode for Reversible Protonic Solid Oxide Cells.

Reversible protonic solid oxide cells (R-PSOCs) are promising green energy storage devices for efficient hydrogen/electricity conversion. Due to the complex environment of the air electrode, the microscopic influence mechanism of oxygen vacancies in perovskites on oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is unclear. In this study, the layered Ruddlesden-Popper perovskite Ln2NiO4 (Ln = La, Pr, Nd) air electrodes are constructed to investigate the effect of oxygen vacancies on the water/oxygen coupling in dual mode. The Pr2NiO4+δ full cell exhibits the highest peak power density of 0.692 W cm-2 in fuel cell mode and a maximum current density of -1.2 A cm-2 in electrolysis cell mode at 700°C. The changes in electrochemical impedance spectroscopy show that Pr2NiO4+δ can absorb a small amount of interfacial water in SOFC mode to promote triple-conductivity. Meanwhile, it can have good electrolytic performance in an atmosphere of 10% H2O in the SOEC mode. The enriched oxygen vacancies of Pr₂NiO4+δ can provide a broad platform for both the ORR and OER, while the appropriate hydrophilicity can achieve a better balance state by the competitive adsorption of water/oxygen. These comprehensive characteristics make Pr2NiO4+δ suitable to be a potential Ruddlesden-Popper perovskite air electrode material for RSOCs.

RECYCLABLE Fe₃O₄–MgFe₂O₄ SORBENTS AND THEIR Fe/Mg RATIO OPTIMIZATION FOR WATER DECONTAMINATION

Our research aims to investigate a series of MgxFe3-xO4 (x = 0-1) nanomaterials in the context of their application in both treating arsenic-rich groundwater, where they act as magnetic nanosorbents, and in the treatment of water contaminated with organic pollutants, where they serve as agents in magnetic hyperthermia. Magnetization measurements as a function of magnetic field strength and temperature reveal that these materials exhibit a superparamagnetic (SPM) behavior, making them suitable for advanced water purification technologies. Magnetic hyperthermia is a process of induced heating of magnetic nanoparticles in an alternating magnetic field. One of the key aspects of this research was to examine how the substitution of Fe²⁺ with Mg²⁺ in the Fe₃O₄ structure (MgxFe3-xO4, x = 0-0.2) affects the hyperthermic properties of the samples, through the analysis of SLP (Specific Loss Power) and ILP (Intrinsic Loss Power) values. It was found that SLP values increase with frequency for all samples. The highest SLP at 728 kHz was observed for Mg₀.₂Fe₂.₈O₄ (818 W/g), whereas Fe₃O₄ at the same frequency exhibited 327 W/g. The Mg₀.₂Fe₂.₈O₄ sample has the highest ILP value at 728 kHz (1.404 nHm²/kg), making it the most efficient for hyperthermia applications. The excellent heating efficiency of MgxFe3-xO4 nanoparticles makes them suitable for applications in technologies for the degradation of organic contaminants based on magnetic hyperthermia. Preliminary results of testing MgxFe3-xO4 as sorbents for arsenic removal from groundwater indicate their significant potential and the need for further optimization of the chemical composition and microstructural properties of the nanoparticles. It has been shown that arsenic concentration in groundwater can be reduced from 102 ppb to 14 ppb within 30 minutes using a sorbent concentration of only 0.1 g/L. At the same time, the phosphorus concentration decreased from 381 ppb to 83 ppb, indicating competitive adsorption between phosphate and arsenate ions on the sorbent surface. This suggests that phosphate anions occupy similar adsorption sites as arsenate, which may influence the efficiency of arsenic removal in real groundwater systems with varying phosphate concentrations. Although the phosphorus concentration after treatment remains above the normal range for drinking water, further studies are required to enhance the selectivity and capacity of the material, ensuring both effective arsenic removal and the production of safe drinking water.

The Influence Mechanism of Dissolved Organic Matter on the Photocatalytic Oxidation of Pharmaceuticals and Personal Care Products

With the worsening global water pollution crisis, pharmaceuticals and personal care products (PPCPs) have been increasingly detected in aquatic environments. The effective removal of PPCPs remains challenging for conventional water treatment technologies, whereas photocatalytic technology has shown distinct promise. Dissolved organic matter (DOM), a ubiquitous component of aquatic ecosystems, exerts multifaceted effects on the photocatalytic oxidation of PPCPs. In this article, the influence of DOM on the performance of various photocatalysts in PPCP removal is systematically summarized and analyzed. This review highlights DOM’s role in altering the migration and transformation of PPCPs via processes including adsorption and complexation. The adsorption of PPCPs on photocatalysts is achieved by competitive adsorption or by providing more adsorption sites. DOM modifies the structural properties of photocatalysts through mechanisms such as ligand exchange, intermolecular forces, electrostatic forces, and hydrophobic interactions. DOM inhibits the formation of active species via light attenuation and shielding effects while simultaneously enhancing their generation through photosensitization and electron transfer facilitation. In this review, the interaction mechanism among DOM, PPCPs, and photocatalysts within the PPCP photocatalytic oxidation system is expounded on. These findings provide novel insights into optimizing photocatalytic reaction conditions and enhancing treatment efficiency, while providing a theoretical foundation for advancing efficient, eco-friendly PPCPs remediation technologies.

Effect of humic acid on the adsorption of selenium by lepidocrocite

Selenium (Se) mobility and bioavailability in natural environments are influenced by its adsorption at the aqueous interface of lepidocrocite (Lep), which is significantly affected by humic acid (HA), a common natural organic matter (NOM). This study investigated the mechanisms by which HA influences Se adsorption on Lep, aiming to understand how HA affects Se speciation, distribution, and mobility in natural environments. Batch experiments were conducted using synthetic Lep and HA under varying pH values (4-8) and HA concentrations (10-100 mg C/L). Interactions among HA, Lep, and Se were characterized using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Zeta potential and hydrodynamic diameter measurements were also performed to evaluate colloidal stability. HA significantly reduced Se adsorption on Lep by competing for adsorption sites, forming coordination bonds with Se, and altering Lep’s surface charge and hydrophobicity. At higher HA concentrations, dissolved and colloidal Se increased, while particulate Se decreased. Lower pH enhanced Se adsorption due to protonation, whereas higher pH promoted Se mobility. FTIR and SEM analyses confirmed HA’s role in modifying Lep’s surface properties and influencing Se adsorption behavior. HA plays a critical role in modulating Se adsorption on Lep through competitive adsorption, coordination interactions, and surface modification. These mechanisms influence Se speciation, distribution, and mobility, with implications for managing Se bioavailability in agricultural and environmental systems. This study provides insights into the geochemical cycling of Se and offers guidance for optimizing Se-rich agricultural practices.

Simultaneous adsorption of cadmium and arsenic by goethite-modified rice straw-derived biochar in water and soil: interactive ion effects and co-adsorption mechanism.

The coexistence of cadmium (Cd(II)) and arsenic (As(III)) has long been an environmental problem. Green and cost-effective biochar (BC) shows considerable potential for addressing environmental issues, including the concurrent elimination of cadmium (Cd(II)) and arsenic (As(III)) from water and soil after nano-sized goethite modification. However, the behavior of goethite-modified rice straw-derived biochar (GBC) during co-adsorption of Cd (II)) and As (III)) in the presence of competing ions and anoxic vs oxic environments is unclear yet. This experiment (GBC) was successfully synthesized to study co-adsorption and the effects of environmental factors on it. The adsorption kinetics and isotherms for the mixed adsorption of Cd(II) and As(III) onto GBC showed that the pseudo-2nd-order model (R2 Cd(II) = 0.998, R2 As(III) = 0.996) and the Langmuir model (R2 Cd(II) = 0.982, R2 As(III) = 0.997) were both correctly portrayed. The highest adsorption of As(III) was 87.38mg/g, and Cd(II) was 71.07mg/g in a single adsorption system, which is considerably more significant than the values of 68.6 and 48.38mg/g, correspondingly, in the co-adsorption system. The competitive adsorption of Cd(II) and As(III) on GBC was primarily driven by co-precipitation and ion exchange. Its efficacy in soil systems under aerobic and anaerobic situations remained undisturbed. At the same time, the anaerobic environment favors Cd adsorption, and the aerobic environment favors more As remediation in an aqueous system. The interactive ions Ca2+ and Mg2+ significantly enhanced the adsorption of As(III). On the other hand, phosphate and humic acid significantly promote Cd(II) adsorption. In summary, the different environmentalconditions revealed by this study help a deeper understanding of the behaviors of As and Cd by GBC.

A novel sulfonated polybenzothiazole-based adsorbent for simultaneous capture of organic dyes from aqueous solution

ABSTRACT In this study, we synthesized a novel sulfonated polybenzothiazole (sPBT) which permitted the development of a sodium alginate-based composite (SA-sPBT), and this composite demonstrated promising potential as an adsorbent for the simultaneous removal of Malachite Green (MG) and Neutral Red (NR) from aqueous solutions. Experimental results revealed that SA-sPBT exhibited excellent adsorption performance for MG and NR in both single and binary dye systems. The adsorption isotherms of MG and NR in single-dye systems were well described by the Langmuir model. Kinetic studies showed that both MG and NR adsorption aligned with pseudo-second-order and pseudo-first-order models, respectively. Thermodynamic analyses indicated that the adsorption processes for both dyes were endothermic, spontaneous and feasible. The statistical physics model revealed distinct adsorption behaviors: in single-component systems, NR was adsorbed predominantly via pure non-parallel orientations, while MG exhibited no pure non-parallel orientation at a single adsorption site on SA-sPBT. In the binary dye system, competitive adsorption was observed, with NR showing higher adsorption energy compared to MG, leading to its preferential attachment to adsorption sites. Mechanistic insights were further explored using FT-IR, XPS and DFT calculations, confirming the efficacy of the SA-sPBT composite for organic dye removal from wastewater.

TEMPO-Oxidized Spruce Galactoglucomannan-Biopolymer with Enhanced Antioxidant Activity and Selective Heavy-Metal Sorption.

This study examines galactoglucomannan, a well-studied biopolymer isolated from Siberian spruce (Picea obovata Ledeb). Due to its structure, abundant with hydroxyl groups, galactoglucomannan's properties, such as heavy-metal ion affinity, are considered to be mediocre. Nevertheless, there are various ways to enhance its functionality via oxidative TEMPO/NaBr/NaOCl processing. This work is concerned with the determination of the oxidation effect on the structure and performance properties, such as thermal decomposition behavior, antioxidant activity, and selective heavy-metal sorption. In the results, TEMPO-oxidized galactoglucomannan yields vary in the range of 78.3 ± 6.4 wt.%. The carboxylate group in the oxidized derivative represents up to 0.084 g/1 g of the sample. According to antioxidant activity tests, the oxidized galactoglucomannan exceeds the initial sample in terms of hydroxyl radical scavenging ability. The spectral characteristics of the initial and oxidized galactoglucomannan samples reveal the differences in absorption units (1725, 1610, and 1371 cm-1). The preservation of the polymeric structure was confirmed by the gel permeation chromatography analysis results. The heavy-metal ion capacity of galactoglucomannan is higher for the oxidized derivative, which demonstrated Cd2+, Fe2+, Cu2+, and Pb2+ adsorption values of 166.8 mg/g, 142.8 mg/g, 150.0 mg/g, and 199.2 mg/g, accordingly. The obtained result of the competitive heavy-metal ion adsorption of oxidized galactoglucomannan also exceeds its initial form, as characterized by its summary 143.1 mg/g capacity.

Calcium Alginate Aerogel-MIL160 Nanocomposites for CO2 Removal.

Using MOFs in powder form leads to mass transfer limitations and large pressure drops in packed bed adsorbers. Use of MOF/aerogel composites (called MOFACs) in bead form could overcome these challenges without compromising the MOF's adsorption performance, as observed with other shaping methods, such as the use of polymeric binders. In this study, Ca-alginate-aerogel-MIL-160(Al) MOFACs (AlgMIL160) were prepared via sol/gel-assisted direct mixing methods, followed by supercritical drying. The gas sorption, powder X-ray diffraction, FTIR, and scanning electron microscopy characterization results showed that the MOF was successfully incorporated into the aerogel, while the MOF structure was preserved. Adsorption measurements were carried out in both static single-component and dynamic binary gas mixture modes. Obtained isotherms were successfully fitted to the Langmuir model followed by ideal adsorbed solution theory (IAST). The single-component gas adsorption isotherms of CO2 on MOFACs with MIL-160(Al) loadings of 25, 50, and 75 wt % revealed a CO2 uptake of 0.43, 0.70, and 0.98 mmol/g at 150 mbar and 25 °C which were higher than that of pure MOF (1.23 mmol/g) based on the MOF loading in the composites, showing the synergistic effect of aerogel and MOF composites. Incorporation of MIL-160(Al) into the aerogel network which is comprised of 75% MIL-160(Al) and 25% Ca-alginate aerogel enhanced MIL-160(Al)'s CO2/N2 IAST selectivity from 53 to 70 at 25 °C and 1000 mbar. Both experimental and simulated CO2 adsorption isotherms showed good agreement. The dynamic adsorption performance of the MOFACs studied by using a binary mixture of 15% CO2/85% N2 was close to the single-component CO2 adsorption with slightly decreased uptake showing the competitive adsorptions between CO2 and N2 molecules. This novel nanocomposite with remarkable CO2 capture performance can be used in gas adsorbers without causing large pressure drops.

Competitive adsorption of Congo red by sawdust in the presence of reactive black 5 and the effect of ionic strength

ABSTRACT Industrial revolution has led to the release of contaminants into water bodies, with multiple pollutants often co-existing. This study investigates the competitive adsorption of Congo red and Reactive black 5 considering initial dye concentration, time, adsorbent dosage, solution pH and temperature. Furthermore, the effect of ionic strength (NaCl, BaCl2, Na2SO4, and CuSO4) on Congo red adsorption was also examined. The adsorbent was characterized using Fourier Transform Infrared Spectroscopy, Scanning Electron Microscope, and pH-point of zero charge. Result indicated that increasing initial dye concentration decreased the percentage removal of Congo red in both single and binary system, with the removal rate being lower in the binary system, suggesting competitive adsorption. Increasing adsorbent dosage and temperature led to increased percentage removal. The optimum pH of the adsorption process was noted at pH 5. BaCl2 and CuSO4 exhibited the most significant enhancing influence on Congo red adsorption. Equilibrium data was modelled using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models revealing a maximum monolayer adsorption capacity of 27.29 mg/g in the single system which reduces to 21.48 mg/g in the binary system indicating antagonistic effect of Reactive black 5 on Congo red adsorption. Thermodynamic studies revealed that the adsorption process was endothermic and spontaneous at higher temperature.