The thermolysis of K3CrO8 is characterized by autocatalytic-kinetics and the mean values of effective Arrhenius parameters are E = 69 ± 12 kJ mol−1, log A = 7 ± 2 s−1. Mass spectrometer, microscopic, X-ray diffraction and particularly ESR-sprectroscopic studies, as well as specific surface mea...

Ethyl bromide and aluminum powder were irradiated with ultrasound to form ethylaluminum sesquibromide, which was then treated with triethyl borate to give triethylborane in satisfactory yield and purity. In comparison to other existing methods, ultrasonic irradiation seems to be a simple and eff...

Siderite as a Fe(II)-bearing mineral often be naturally weathered and oxidized into goethite, which would decrease the surface chemical activity of the siderite. The chemical activity of siderite is improved by decomposing weathering-formed goethite at low temperature (350 °C). The activated na...

A cation exchange chromatography method employing sulfonated polysterene cation resin (DOWEX AG50-X8) was developed in order to separate rare-earth elements (REEs) from uranium-rich materials. The chemical separation scheme is designed to reduce matrix effects and consequently yield enhanced ion...

The stability of calcium silicate hydrate (C-S-H) gel doped with uranium to form calcium uranium silicate hydrate (C-U-S-H) gel was investigated in 2.5 M NaCl, 2.5 M NaCl/0.02 M Na2SO4, 2.5 M NaCl/0.02 M NaHCO3 or 0.02 M NaHCO3 solutions relevant to the geological disposal of radioactive waste. ...

Combined sorption of U(VI) and phosphate ions on red clay was studied in their concentration range 0.1–1 mM/dm3. The sorption of uranium and phosphate ions was investigated and compared on several clay forms: NaCl, T-clay, H-clay, HDTMA-clay and R-clay. The order of constant distributions was l...

The purpose of this study was to investigate the adsorption of uranium (VI) ions on the polypyrrole adsorbent. Polypyrrole was synthesized by a chemical method using polyethylene glycol, sodium dodecylbenzenesulfonate, and cetyltrimethylammonium bromide as the surfactant and iron (III) chloride ...

Recently, magnetically modified nanomaterials have gained a great interest in the field of wastewater remediation. In this regard, the present work introduces a facile microwave-assisted pathway for the preparation of magnetically modified hydroxyapatite nanoparticles (MNHA) and evaluates its ad...

We developed a novel solidification and stabilization process using a nanoscale zerovalent iron (NZVI)-cement system for reductive immobilization of hexavalent uranium (U(VI)) in a soil–cement matrix. The NZVI suspension without cement demonstrated high removal efficiency (100% in 2 h) and fast...

The effect of pH, contact time, temperature, ionic strength and initial U(VI) concentration on U(VI) sorption onto K-feldspar was investigated using batch techniques. The sorption kinetics was evaluated and the activation energy was obtained based on the rate constants at different temperature. ...

There is a need to develop highly efficient materials for capturing uranium from nuclear wastewater. Here, 5-methylbenzotriazole modified graphene oxide (MBTA-GO) was used to adsorb U(VI) from aqueous solution. By the trials of different conditions, we found that the removal of U(VI) from acidic...

Biological uranium (VI) reduction was investigated using a mixed-culture of U(VI) reducing bacteria isolated from tailing dumps at an abandoned uranium mine in Pharaborwa (Limpopo Province, South Africa). A fixed-film reactor was used in the investigation, whereby the reactor was operated in the...

This paper evaluates the feasibility of using niobium-based catalysts for the photodegradation of organic dyes. The metal oxides were prepared using niobium scraps and chips as precursors. The semiconductors were characterized by diffuse reflectance spectroscopy, scanning electron microscopy (SE...

γ-La2S3 nanoparticles were successfully prepared by thermal decomposition of lanthanum complex La(Et2S2CN)3·phen at low temperature. The obtained sample was characterized by the X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and element analysis. The decomposition mechanism...

Lanthanum sulfide thin films were prepared on glass substrates from aqueous medium using spray pyrolysis technique. The effect of preparative parameters such as substrate temperature and solution concentration on the films was studied. The lanthanum sulfide films were annealed in air at 300 °C ...

In this work, the electrochemical properties of rare earth lanthanum sulfide (La2S3) films obtained by chemical bath deposition method are investigated as an electrode material for supercapacitor application. The effect of air annealing on structural, surface morphological and wettability proper...

Solid electrolyte is the key point for developing all-solid-state lithium-ion battery with good recyclability and no safety problem. Here, a crystalline phase of lanthanum sulfide (La2S3) was incorporated into glassy sulfide-based solid electrolytes (Li2S–SiS2 or Li2S–P2S5) to form two composi...

Lead free niobium modified piezoelectric ceramics Bi0.5Na0.25K0.25NbxTi1-xO3 (BNKT) (x = 0.0, 0.015 and 0.025) compositions along with their structural and opto-electrical properties are investigated. At room temperature Rietveld refinement analysis on x-ray diffraction data revealed the evidenc...

Single crystals of Ba3Na0.32Nb6O12(Si2O7)2 were grown for the first time. The use of an alkali/alkaline earth eutectic flux facilitated the crystal growth. Ba3Na0.32Nb6O12(Si2O7)2, a mixed valent Nb(V)/Nb(IV) compound, crystallizes in the noncentrosymmetric hexagonal space group P-62m with a = 8...

Niobium barium phosphate glasses were prepared by melting different compositions of P2O5–Nb2O5–BaO–K2O in an induction furnace. Three routes of preparation were adopted: (a) the material was melted at 1300°C, cast in a stainless steel mould and cooled to room temperature with a rod placed in...