Concentration Of CeCl3 Research Articles

CeCl3 concentration effects on cyclic voltammogram overlap in LiCl-KCl eutectic molten salt

In the present study, cyclic voltammetry was performed to investigate CeCl3 in a LiCl-KCl eutectic molten salt at various concentrations. The results indicate that the overlap degree of cyclic voltammograms at different cycles deteriorates with the increasing CeCl3 concentration in the molten salt. This phenomenon was attributed to higher concentrations of CeCl3, which led to a non-uniform film on the electrode surface. This was evidenced by material characterization of the working electrode after cyclic voltammetry (CV) testing and the simulated cyclic voltammograms of a reversible electrochemical reaction. This study will provide new insights that enhance our understanding of the electrochemistry of the CeCl3-LiCl-KCl system and offer valuable reference for other soluble-insoluble electrochemical systems.

Phosphate adsorption characteristics of CeO2-loaded, Eucommia ulmoides leaf residue biochar

In this study, a Ce-loading biochar (Ce-BC) was synthesized by the optimal modification method of pre-pyrolysis impregnation, a pyrolysis temperature at 600 °C, and a CeCl3 concentration of 1.00 mol L−1 for efficient adsorption phosphorus (P) from wastewater. The results revealed that Ce-BC could achieve a maximum P removal rate of 100% under specific conditions: an adsorbent concentration of 2.00 g L−1, an initial solution pH of 3.00, an adsorption temperature of 25 °C, and an initial P concentration of 20.00 mg L−1. The adsorption process followed the quasi-secondary kinetic model, suggesting the Ce-BC was particularly effective in acidic environments. Meanwhile, Ce-BC has a strong resistance to anion interference and good cycling performance (the P adsorption capacity of Ce-BC was 59.77% of its initial value after four cycles). Field emission scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) indicated that Ce-BC contained a porous structure and rich functional groups (hydroxyl and carboxyl), and compounds of CeO2 and MgCeO3 were formed. The Ce loading favored the exchange with P through ligands, inner-sphere complexation, ion exchange, and electrostatic interaction to form inner-sphere complex-cerium P (CePO4), and the surface complex of Ce-O-P replaced O-H. In addition, the Ce-BC adsorption columns substantially affected P removal in actual wastewater. Overall, Ce-BC is a promising material for the treating P-containing acidic wastewater.

Synthesis of lactide from alkyl lactates catalyzed by lanthanide salts

Cerium salt exhibited a highest catalytic activity in the conversion of ethyl and isopropyl oligolactates into lactide. A maximum yield of the target product was reached at the concentration of CeCl3·7H2O ranging from 1 to 4 mol% relative to the lactide units in ethyl and isopropyl oligolactates. A gradual reduction of the pressure from 50 to 5 Torr along with the temperature increase from 180 to 230 °C during depolymerization resulted in the product containing up to 94% lactide.

Differential interaction of cerium chloride with bovine liver catalase: A computational and biophysical study

In this study, Cerium chloride-induced conformational changes of Bovine Liver Catalase (BLC) has been investigated by molecular docking and further supported by various biophysical techniques. The temporal change of catalytic activity of BLC has also been studied in presence of Ce(III) with different buffer solution in vitro at 25 °C. The differential binding of Ce(III) to BLC observed by simulation study was well supported by the differential regulation of BLC activity in different buffers. After 1 h of incubation with CeCl3, the reduction in activity of BLC was maximum in MOPS, HEPES and Tris buffer, whereas no change in activity was noticed in phosphate buffer. Isothermal Titration Calorimetric (ITC) study also supports the differential binding of Ce(III) to BLC in different buffers. Ce(III)-induced conformational transition in BLC was followed as a function of concentration. Nevertheless, with 24 h incubation of CeCl3 the activity of BLC was highest with higher molar concentration of CeCl3 suggesting the conformational stability of BLC in presence of Ce(III). The compromised activity of BLC in response to Ce(III) is due to the induced conformational change and the degree of change in secondary conformation of BLC was maximum in MOPS, HEPES and Tris and least in phosphate buffer. Therefore, the reduced activity of BLC is controlled by the direct interaction of Ce(III) in the active site of BLC in Tris buffer or indirect interaction of Ce(III) in the non-active site of BLC in MOPS and HEPES buffer.

Simulation of Process and Reactor Structure Optimization for CeO2 Preparation from Jet-Flow Pyrolysis

The pyrolysis reactions within a self-made jet pyrolysis reactor were simulated using FLUENT software. The effects of process parameters and reactor structural parameters on the pyrolysis reaction efficiency were studied. Within certain ranges, the CeO2 yield can be improved by reducing the inlet fuel flow rate or by increasing the CeCl3 concentration. To ensure two-phase mixing homogeneity and reaction efficiency inside the reactor, the optimized value of the diameter ratio of the drainage pipe to the throat mouth is 10/5, the angle between the drainage pipe and the throat mouth is 90°, and the drainage pipe diameter is 10 mm.

High Temperature Corrosion of 12Kh18N10T Steel in Molten Lithium and Potassium Chlorides with a Cerium Trichloride Addition

The high temperature corrosion of the 12Kh18N10T steel in molten lithium and potassium chlorides with a cerium trichloride addition is studied at 773 K. The CeCl3 concentration is varied from 0.2 to 5 mol %. Cerium is used as an analog of plutonium. The electrolyte composition is close to the compositions of the real electrolytes used for processing of nitride spent nuclear fuel. The main research method is gravimetry, with holding a steel sample in a melt for 1–24 h. In addition, atomic adsorption and electron-probe microanalysis are used.

Potentiometric Measurement of Activity of Rare Earth Chlorides (La, Gd, Ce, Nd) in LiCl-KCl Eutectic Salt

In this paper, the thermodynamic activity of two lanthanide chlorides (CeCl3 and NdCl3) in molten LiCl-KCl eutectic salt measured using open circuit potentiometry has been reported. Activity coefficient of CeCl3 was found to be strongly dependent on the concentration of CeCl3 in a concentration window of up to 4.66 mol % CeCl3. The activity coefficient of NdCl3 could not be measured due to the uncertainty in NdCl3/NdCl2 molar ratio in the salt, however the thermodynamic activity was measured relative to a 5 mol% Ag∣AgCl reference electrode.The concurrent analysis of data presented in this paper along with previously published activity data for LaCl3 and GdCl3 demonstrates that the departure from ideal solution behavior shown by the rare earths chlorides correlates with ionic size of underlying rare earth element. The smaller the ionic size of the species under consideration, the greater its departure from ideal solution behavior. Further, using the activity data of all four rare earth chlorides, an ionic size dependent correlation was developed. Using this empirical correlation, it is possible to calculate the activity of all species from La(Z = 57) to Gd (Z = 64) for a concentration of up to 2.5 mol% rare earth chloride in LiCl-KCl molten salt at 773 K.

Cerium Chloride Application Promotes Wound Healing and Cell Proliferation in Human Foreskin Fibroblasts.

This study investigated the effect of cerium chloride (CeCl3) on cell migration and gene expression of human foreskin fibroblasts (HFF). HFF were exposed to three different CeCl3 solutions (1%, 5% and 10%, w/v %) for three different time durations (1, 5 and 10 min). 72 h after exposure to CeCl3, cell viability was assessed by MTT test. A scratch-wounded assay determined the cell migration and the width of the wound, measured at 24 h. Gene expression patterns for cyclins B1, D1 and E1 were analyzed by RT-PCR (p < 0.05, t-test). The viability proliferation increased at 1- and 5-min exposures for all CeCl3 concentrations, in contrast to no treatment (p < 0.05 at 24 h). No influence of CeCl3 was found after 10 min. The scratch assay showed increased cell migration up to 60% at 1 and 5 min after 24 h at 5% and 10%. Cyclin B1, D1 and E1 all showed upregulation, confirming an increase in cell proliferation. This study demonstrates that exposure time and concentration of CeCl3 may have a positive effect on fibroblast viability and migration. Application of CeCl3 may be beneficial as a cell-stimulating agent leading to therapeutic tissue fibrosis or more resistant tissue around teeth, when warranted, during different periodontal therapies.

Cyclic Voltammetry on CeCl3 in LiCl-KCl Eutectic Using W and Bi Coated Electrode

This paper presents experimental results of cyclic voltammetry on CeCl3 in LiCl-KCl using tungsten electrode and Bi coated electrode respectively at 703K. Using tungsten electrode at low concentration of CeCl3, the redox reaction has been shown to be reversible. Diffusion coefficient and apparent standard potential of Ce(III) in LiCl-KCl were 0.42×10-5 (cm2/s) and -3.153 (V vs. Cl2/Cl−) under 50mV/s. In order to obtain Bi coated electrode, cyclic voltammetry was carried out on eutectic salt including BiCl3. The redox reaction of Ce on Bi coated electrode has been shown to be reversible and apparent standard potential on Bi coated electrode moved 782mV compared with tungsten cathode.

Electrochemical Properties and Analyses of CeCl3 in LiCl-KCl Eutectic Salt

Thermodynamic and electrochemical properties of cerium in LiCl-KCl eutectic salt have been measured and studied at different concentrations (0.5 – 4 wt%) and temperatures (698 K – 798 K) via both cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques as a part of developing a fundamental understanding and methodology in materials detection and accountability for pyroprocessing technology. CV experiments were performed to determine the diffusion coefficient and apparent standard potential of CeCl3 on the tungsten working electrode. The diffusion coefficient was calculated by using Delahay equation, and raging from 0.48 × 10−5 to 1.01 × 10−5 cm2 s−1. Results reveal that the calculated diffusion coefficient of CeCl3 in the salt follows the Arrhenius temperature relationship and it is weakly affected by the changes in concentration of CeCl3. The apparent standard potentials were calculated from peak potentials showing linear relationship with temperature. Exchange current density values of Ce3+/Ce couple in the salt were obtained from EIS experiments, ranging from 0.0076 A cm−2 to 0.18 A cm−2. The results indicate that these values follow Arrhenius temperature dependence and increase when CeCl3 concentration increases.

Study on purification and application of novel precipitant for ceria-based polishing powder

Novel precipitant prepared through carbonation with MgCl2 wastewater generated from rare earth extraction separation process and low-price dolomite as raw materials was studied in this paper. The purification methods of novel precipitant by adding appropriate oxidizing agent were studied. It was found that optimal purification result could be achieved with sodium hypochlorite as iron removal reagent and the iron removal rate could reach up to 90% when the adding amount was 0.1 vol.%. During the preparation, the particle size and distribution of ceria-based polishing powder were affected obviously by the parameters such as concentration, reaction temperature and feeding rate. The results showed that ceria-based polishing powder with D50=2.5–3.5 μm and the particle size distribution of 0.65–0.75 μm could be prepared when the concentration of CeCl3 was 0.6 mol/L, the reaction temperature was maintained at 50 °C and the feeding speed was controlled at 25 ml/min. Compared with commercial powder, the self-made polishing powder had roughly the same cutting amount, but the surface finish of polished glass was better than that of commercial polishing powder.

Corrosion Inhibition of Aluminium Anode by CeCl&lt;sub&gt;3&lt;/sub&gt; in Simulated Seawater

Corrosion of aluminium anode in the seawater will reduce the life of the aluminum-air cell. It has been recognized that addition of inhibitor into the seawater electrolyte is an effective method that may prevent the corrosion of aluminium anode.The corrosion inhibition behavior of aluminium anode after addition of CeCl3 with different concentrations in simulated seawater has been investigated in this paper. EIS results showed that there was a significant increase of corrosion resistance when the concentration of CeCl3 reached 500mg·L-1 in simulated seawater, compared to the case without inhibitor. Potentiodynamic polarization curves showed that CeCl3 was a cathodic inhibitor in simulated seawater. SEM and XPS confirmed that the cerium oxide/hydroxide were formed at micro-cathodic areas of aluminum surface,which decreased the corrosion rate of aluminium anode.

Effects of cathodic electrodeposition parameters of cerium oxide film on the corrosion resistance of the 2024 Al alloy

AbstractCerium oxide thin films obtained by cathodic electrodeposition on 2024 aluminium alloy have been studied. The coatings, obtained with electrochemical deposition, offer an effective corrosion protection and require a lower deposition time when compared to chemical conversion coatings. The coatings were obtained at room temperature by deposition from CeCl3/H2O2 aqueous solutions and the influence of several parameters (CeCl3 concentration, H2O2 concentration, deposition time, current intensity) on the corrosion resistance was studied. The composition, morphology and microstructure of the films have been characterized by SEM, XPS and AFM. The corrosion resistance was investigated through potentiodynamic tests in 3% NaCl solution.

Study of sol–gel process for preparing cerium nano-oxide films on AA7020-T6 Al alloy

A design of experiment technique, the Taguchi method, has been used to optimise a coating process in order to decrease the corrosion rate and increase the passivity of the coated samples by controlling the coating process’s factors. Potentiodynamic polarisation measurements were carried out to determine the corrosion rate and passivity of the coated samples. The optimised coating parameters for corrosion rate are one molar ratio for acid citric/CeCl3, 300°C for heat treatment temperature, 0·02 mol for CeCl3 concentration and 0 min for time of boiling. The optimised coating parameters for passive region are two molar ratio for acid citric/CeCl3, 300°C for heat treatment temperature, 0·001 mol for CeCl3 concentration and 60 min for time of boiling. The results showed that the acid citric/CeCl3 is the most significant factor affecting the corrosion rate while the time of boiling affects significantly on the passive region of the coatings.

Violet–blue luminescence from hafnium oxide layers doped with CeCl3 prepared by the spray pyrolysis process

AbstractHfO2:CeCl3 coatings were deposited by the spray pyrolysis method employing hafnium dichloride oxide and CeCl3 dissolved in deionized water (18 MΩ/cm). The room temperature photoluminescence characteristics of the HfO2:CeCl3 films were studied as a function of the deposition parameters such as doping concentrations and substrate temperature. The presence of two different Ce3+ centres in HfO2 is detected from photoluminescence measurements. A reduction of the luminescence intensity is observed with an increase of both the CeCl3 concentration and the deposition temperature. X‐ray diffraction measurements of these films showed that the crystalline structure depends on the substrate temperature. For substrate temperatures less than 350 °C the deposited films are almost amorphous, while substrate temperatures higher than 400 °C produce diffraction peaks corresponding to the monoclinic phase of HfO2. The chemical composition of the films as determined by energy dispersive spectroscopy is also reported. Furthermore, the surface morphology characteristics of the coatings, as a function of the deposition temperature, are also presented. (© 2007 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)

塩化セリウムを用いた凝集沈殿法によるほう素含有排水の処理に関する検討

The efficiency of removing boron from industrial wastewater by coagulation sedimentation with the coagulant cerium chloride (CeCl3) was determined. The optimum processing conditions were investigated in a batch processing experiment conducted by supplying 100 mg ·l-1 boron to a reactor. The optimum processing conditions were a pH of about 10, cerium addition to give a Ce/B molar ratio (molarity of Ce/molarity of B ) of 2 or more, and a processing time in the range of 5-30 minutes. The removal efficiency for boron decreased when sulphate ions were coexisted at a concentration of about six times or more of boron concentration. However, it was improved by performing coagulation sedimentation using calcium chloride (CaCl2) and by increasing CeCl3 concentration. When the effect of processing was examined using actual industrial wastewater under the determined optimum processing conditions, the removal efficiency for boron was in the range of 87-92%. When a field processing experiment was conducted by setting up small batch experiment equipment next to the wastewater treatment equipment, the removal efficiency for boron was 93%. This was about 58% higher than that of actual wastewater treatment equipment. Moreover, fluorine and SS (suspended solid) were successfully removed in addition to boron.

Use of the cerium chloride technique and energy dispersive X-ray microanalysis in plant peroxisome identification

Glycolate oxidase activity is demonstrated cytochemically with the CeCl3 technique in leaf peroxisomes ofNicotiana tabacum, Glycine max, Psychotria punctata and in unspecialized peroxisomes ofYucca torreyi roots. Reaction product deposition occurs throughout peroxisomal matrices, whereas nucleoid inclusion bodies, occurring in all four species, are cytochemically unreactive. We observed reactive and nonreactive microbodies within individual cells in these four plants despite prolonged incubation times and increased CeCl3 concentration. These results may reflect differences in glycolate oxidase content or peroxisomal differentiation within individual cells of a given tissue. We demonstrate substrate-independent cerium deposits in cell walls, cytoplasmic hoop-shaped structures and chloroplast thylakoids at extended incubation times or increased CeCl3 concentration, perhaps indicating the presence of endogenous H2O2. Elemental spectral analysis of electron-dense deposits with energy dispersive X-ray microanalysis using a STEM detects peaks generated from the L-series of cerium. SEM X-ray mapping for the Lα1 peak of cerium verifies peroxisomal localization of reaction product in thin sections.