Adsorption Of La3 Research Articles

Selective recovery of La3+ from rare earth mine tailwater by titanium phosphate adsorbents with different crystal forms

Titanium phosphate (TiP) materials in different crystalline forms—amorphous TiP (am-TiP), scaly TiP (s-TiP), platy TiP (p-TiP) and alpha-type TiP (α-TiP) were synthesized by using titanium source of TiOSO4 and phosphorus source of H3PO4. The structures and properties of the four TiP materials and their adsorption selectivity for rare earth La3+ ions were studied. The results showed that the ion exchangeability of TiP was related to the phosphate groups in the structures. The -HPO4 groups dominated the phosphate groups of am- and p-TiP, while -H2PO4 and-HPO4 groups were the only phosphate groups of s- and α-TiP, respectively. La3+ ions were mainly adsorbed through ion exchange with H+ of P-OH groups of TiP. However, the adsorption was not only related to the cation exchange capacity, but also to the structure features of the materials. The adsorption capacity for La3+ was negatively correlated with the crystallinity of TiP, which decreased in the order of 102.25 (am-TiP) >56.08 (s-TiP) > 22.77 (p-TiP) > 6.79 mg⋅g−1 (α-TiP). The adsorption of La3+ by TiP was basically unaffected by the mono- and di-valent impurity ions except for the tri-valent ions, such as Al3+. Additionally, the semi-crystalline s-TiP had the best desorption and regeneration performance among the four TiP.

Adsorption properties of nanotube type halloysite clay mineral for La<sup>3+</sup> ions

This paper presents the results of research on the adsorption capacity of La3+ ions from aqueous solution of nanotube-type halloysite. The influence of operational conditions such as contact time, initial concentration of La3+, initial pH of solution, halloysite mass and temperature on the adsorption of La3+ had also been examined. The results show that the optimal efficiency and adsorption capacity of La3+ reached 90.19% and 3.76 mg/g in the suitable conditions: haloysite mass 0.6 g/50 mL solution, initial La3+ ion concentration 50 mg/L, pH 5.8, contact time 60 minutes at room temperature (25oC). The adsorption isotherm was studied based on both Langmuir and Freundlich models. The adsorption kinetics were studied by both pseudo-first-order and pseudo-second-order kinetic models. These results open up prospects for the application of haloysite clay minerals to remove and recover La in polluted water.

Fast and efficient adsorption of La3+ by magnetic Fe3O4-modified HA/NH2-MCM-48 composites

Co-mixing of HA with NH2-MCM-48 to form a precipitate by wet synthesis method using NH2-MCM-48 as a substrate. Then Fe3O4 nanoparticles were composited with HA/NH2-MCM-48 by alcohol-thermal method to form HA/Fe3O4@NH2-MCM-48 composites, and the composites were characterized. Firstly, the adsorption performance of HA/Fe3O4@NH2-MCM-48 was discussed by adsorption experiments with the control HA/NH2-MCM-48 and NH2-MCM-48 at different influencing factors on the adsorption of La3+. Moreover, the adsorption types and adsorption mechanisms were investigated by isothermal adsorption modeling, kinetic modeling and thermodynamic modeling. In the end, the reusability and stability of the composites was evaluated by cyclic adsorption–desorption experiments. After five repetitive cycle experiments, the composites were able to maintain 82.9 % of the first adsorption amount. The results show that HA/Fe3O4@NH2-MCM-48 has good adsorption performance and magnetic properties for lanthanide ions, which is favorable for recycling. After optimization experiments, the adsorption amount and adsorption rate of HA/Fe3O4@NH2-MCM-48 reached 243.43 mg/g and 81.23 %, and the adsorption equilibrium is reached quickly within 25 min.

Selective and efficient removal of lanthanum ion in aqueous solution by P-doped porous carbon

Adsorption and selective adsorption are effective means of separating rare earths (REs) from aqueous solutions and reducing heavy metal contamination. In this work, bagasse was used as carbon source and phytic acid as phosphorus source and activator, and a simple synthesis strategy was applied to prepare the effective adsorbent P-doped porous carbon (PC) of lanthanum ions (La3+). Doping of P was helpful to enhance the adsorption and selectivity of porous carbon to La3+. Compared with the samples without P-doping, the adsorption capacity of PC on La3+ was increased by >4 times, and the theoretical maximum adsorption capacity is as high as 342.2 mg g−1, which was greater than that of other reported carbon-based materials. In addition, the selective adsorption of PC on La3+ was as high as 96.07 % and 71.07 % not only in the multi-ion coexistence system of La3+, Ni2+, Zn2+, Co2+, Ca2+, and Na+, but also in the La3+/Na+ (1:50) coexistence system with very low La3+ content, respectively. The adsorption of La3+ on PC-800 is mainly chemisorption, where C-P-O, C/P=O and C-O-P groups are the main active sites for adsorption and improves the selectivity. This work can furnish some useful message on designing and synthesizing of carbon-based adsorbent, which has excellent adsorption selectivity in polyionic and low La3+ coexistence systems.

Adsorption of La3+ onto trifluoroacetic acid modified UiO-66-COOH: Adsorption mechanism and application

The application of metal organic frameworks (MOFs) for the recovery of low concentrations of rare-earth elements (REEs) has attracted increasing attention due to the precious value of REEs resources. In this study, UiO-66-COOH was modified by trifluoroacetic acid (TFA) to not only promote material crystallization and the pore structure verified by XRD and SEM characterization, but successfully enhance its adsorption capacity and achieve perfect selectivity for Lanthanum ion (La3+). The adsorption capacity for UiO-66-COOH-24TFA was increased by 58% compared to unmodified material. The adsorption mechanism and application were comprehensively investigated. By adsorption kinetics, isotherm and thermodynamic studies, it was found that the adsorption process mainly exhibited monolayer adsorption with spontaneous endothermic-chemisorption characteristics, and –COOH of the modified materials (UiO-66-COOH-24TFA) played an important role, which was confirmed by XPS. Moreover, UiO-66-COOH-24TFA was applied to REEs actual wastewater by successive six-stage adsorption process, where the overall recovery rate on La3+ reached 94.1% under the coexisting conditions of multiple ions. The application of this acid modified material in the field of the separation and recovery of REEs is of great promise.

Adsorption of rare earth La3+ by α- zirconium phosphate: An experimental and density functional theory study

The α-zirconium phosphate can act as a potential adsorbent for recycling rare earth ions in tailwater because of the abundant surface -POH groups and the layered structure. The adsorption behaviors and mechanism of rare earth La3+ on the material were studied through experimental and density functional theory (DFT) calculation methods. The experimental results show that the adsorption process conformed to pseudo-first-order kinetics and Langmuir isotherm model, with the maximum adsorption amount of 37.1 mg⋅g−1. La3+ was mainly adsorbed through ion exchange with the proton of surface -POH. The presence of impurity Al3+ had a great influence on the adsorption of La3+ on α-ZrP contrary to the case of NH4+. DFT calculations further proved that the oxygen of -ZrOP- and -POH acted as adsorption sites of α-ZrP, and the adsorption energies of La3+, Al3+ and NH4+ were −375.7, −2149.5 and −22.8 kJ⋅mol−1, respectively, in the order of Al3+ > La3+ > NH4+, consistent with the experimental results. The partial density of states (PDOS) suggested that the bonding peaks between La 4d and Os 2p orbitals occurred in the energy range of −9 to 0 eV.

Rare-earth ions as antibacterial agents for woven wool fabric.

Woven fabrics were bestowed with antibacterial property by the simple adsorption of rare-earth metal ions, and the underlying mechanism was investigated using electron spin resonance (ESR) spectroscopy. The adsorption of Ce3+ ions on wool, silk, and cotton fabrics resulted in significant inhibition of Staphylococcus aureus (a gram-positive bacterium), with maximum antibacterial activities (viable bacterial count compared to the reference) of 4.7, 5.8, and 5.2, respectively. Even after 50 wash cycles, the values remained at 3.9, 2.9, and 4.8, respectively. The adsorption of La3+ and Gd3+ ions on wool fabrics also resulted in antibacterial activities of 5.8 and 5.9, respectively. In addition, wool adsorbed with Ce3+ exhibits a satisfactory antibacterial activity of 6.2 against Escherichia coli (a gram-negative bacterium). Such bacterial inhibition is attributed to Fenton reactions between the adsorbed rare-earth ions and hydrogen peroxide (H2O2) produced during bacterial metabolism, as determined from the ESR spectra collected using the spin trap method in the presence of H2O2. The safety of cerium nitrate was also investigated, and no significant issues arose, indicating that it was a safe antibacterial agent. This facile method of imparting antibacterial properties to natural fabrics may be useful for preventing infections in humans.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11696-021-01999-9.

Study of Ions Exchanges during the Adsorption of La3+ Ions onto Montmorillonite K10

Study of Ions Exchanges during the Adsorption of La3+ Ions onto Montmorillonite K10

Molecular mechanism of charge inversion revealed by polar orientation of interfacial water molecules: A heterodyne-detected vibrational sum frequency generation study.

"Charge inversion" is a phenomenon in which multivalent counterions overcompensate for interfacial charges and invert the sign of the net charge near a surface. This phenomenon is believed to be relevant to biologically important processes such as DNA condensation, and hence it has attracted much attention. We investigated the polar orientation of interfacial water molecules at two different negatively charged interfaces in the absence and presence of La3+ using heterodyne-detected vibrational sum frequency generation spectroscopy, which can directly determine the up/down orientation of interfacial molecules. It was found that the orientations of water molecules at a bio-relevant phospholipid interface change from the hydrogen-up to the hydrogen-down with the addition of 10 µM La3+. This change of water orientation indicates that the net charge at the phospholipid interface is inverted by adsorption of La3+ to the phosphate headgroup. By contrast, at an alkylsulfate interface, the majority of the interfacial water molecules remain hydrogen-up orientated even in the presence of 25 mM La3+, indicating that the sulfate headgroup is still solvated by up-oriented water. The observed headgroup specificity suggests that charge inversion at the phospholipid interface originates primarily from the chemical interaction between the phosphate and La3+ ion.

Adsorption of La3+, Ce3+ from Aqueous Solutions by Bayberry Tannin Grafted Chitosan

Bayberry tannin grafted with chitosan (CS-BT) had been successfully prepared and their adsorption performance had been studied La3+, Ce3+ rare earth ions aqueous solutions. The as-prepared absorbents were characterized by Fourier transform infrared spectrometer and scanning electron microscopy. The result showed under optimal conditions [T=40°C; C=2.0 g/L; pH=3.0 (La3+), pH=4.0 (Ce3+);] that the saturation adsorption capacities of CS-BT to La3+, Ce3+ were 58.42 mg/g, 800.08 mg/g, respectively, when [T=30 °C; C=1.0 g/L; pH=4.0 (La3+, Ce3+);] the difference of adsorption quantity between La3+ and Ce3+ reach up to 101.5 mg/g by using the absorbent (CS-BT).The adsorbent exhibited better adsorption capacity to Ce3+ than that of La3+. The CS-BT had high adsorption rate and could achieve basic saturated adsorption in about 5 min. It was found that the adsorption kinetics was well described by the adsorption isotherms followed Freundlich (La3+, Ce3+) adsorption model and the pseudo-second order kinetic model. The research indicated CS-BT could be used as the cheaper and friendly absorbent in enrichment and separation of RE3+ in aqueous solution.

Ligand immobilized novel hybrid adsorbents for rare earth elements (REE) removal from waste water: Assessing the feasibility of using APTES functionalized silica in the hybridization process with chitosan

This experimental study was aimed at checking the potential of employing commercially available amino functionalized silica gels in synthesizing the ligand immobilized hybrid materials rather than the conventional method of utilizing Tetraethyl orthosilicate (TEOS) precursors for the removal of REE from the waste water. The parameters used for the optimization of the synthesis process included the influence of silanes (3-Aminopropyl triethoxysilane APTES/methyltrimethoxy silane MTM), types of ligands (1 – (2-Pyridylazo) 2-naphthol (PAN) and acetylacetone (Acac)), molecular weight and degree of deacetylation of chitosan. Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer Emmett and Teller (BET) and Zeta potential (ZP) analysis were employed to understand the surface characterization of the hybridized adsorbents. The adsorption of La3+, Sc3+ and Y3+ was investigated further in detail using the hybridized PAN adsorbent to understand the effect of initial solution pH, contact time, temperature and initial adsorbate concentration. Single/multi-component system was studied through batch adsorption tests to assess the affinity towards target REEs and the intra series adsorption behavior of light/heavy REEs was also inspected.

Adsorption of La3+ and Ce3+ by poly-γ-glutamic acid crosslinked with polyvinyl alcohol

With the exploitation of rare earth ore, more and more rare earth elements came into groundwater, caused waste of resources and toxicity to the organisms. This study aimed to find an efficient adsorption material to mitigate the above issue. Through doping polyvinyl alcohol with poly-γ-glutamic acid, an immobilised PSP gel particle was produced and had the adsorption rate of La3+ up to 97.10%. The factors including initial concentration of La3+ or Ce3+, adsorbent dosage, pH and temperature of the solution, which potentially affected the adsorption rate and were studied in batch mode. It was found that the optimum adsorption conditions were composed of 50 mg/L La3+/Ce3+ of initial concentration, 600 mg/L (dry mass) biomass for adsorption, pH 6, temperature 30 °C, 150 r/min rotational speed, and 1 h adsorption time. The selective adsorption of 15 different rare earth ions in mixed aqueous solutions were investigated. However, no significant selective differences were observed. Scanning electron microscopy showed that the morphological characteristic of the novel gel was its porous structure, while polyvinyl alcohol gel had a compact structure. Fourier transform infrared spectroscopy suggested that carboxyl groups in the poly-γ-glutamic acid might played a key role in the adsorption process. The adsorption mechanism forecasted to be cation exchange between –COOH and R3+. The adsorption kinetic and thermodynamic process for La3+ and Ce3+ was consistent with the pseudo-second-order equation and Langmuir adsorption isotherm model. It demonstrated that PSP gels particles were useful for removing REEs from wastewater.

Response surface methodology for the optimization of lanthanum removal from an aqueous solution using a Fe3O4/chitosan nanocomposite

In the present work, magnetite nanoparticles/chitosan composites (Fe3O4/CS) were prepared by a chemical precipitation method. We demonstrated the efficient removal of a rare earth metal, lanthanum (La3+), from an aqueous solution using the composite. The removal of La3+ was optimized by using response surface methodology. Analysis of variance and Fisher's F-test were used to determine the reaction parameters which affect the removal of La3+. Optimal conditions, including adsorbent dosage, pH, temperature, and contact time for the removal of La3+, were found to be 6.5 mg, pH 11, 40 °C, and 50 min, respectively. The adsorption capacity was 99.88%. The rate of La3+ adsorption was significantly affected by the solution pH and adsorbent amount. An adsorption isotherm was fitted well by the Freundlich model with a linear regression correlation value of 0.9975. The adsorption of La3+ using the composite followed pseudo second-order kinetics. Thermodynamic studies have revealed that the negative values of Gibbs free energy confirmed the spontaneous and feasible nature of adsorption.

The adhesiveness of the cell surface with regard to its electric and steric structure

Abstract For a biophysical interpretation of the primary step of the cell-cell interaction electrostatic, dispersion and steric forces have to be taken into consideration. To determine the share of these three interaction terms the adhesiveness of erythrocytes and tissue cells was investigated by two independent absolute methods and the electrostatic interaction was estimated by a theoretical model. Modifying the structure of the cell surface (adsorption of La3+ ions, neuraminidase treatment, changing the ionic strength and pH of the suspension medium) and measuring both the stability ratio and the electrophoretic mobility it was shown that the formation of aggregates of erythrocytes is not only determined by the electrical potential but also essentially by the steric structure of the cell surface.