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The experimental data reported in this paper suggest that titanium(IV) oxyhydroxyphosphate-based ion-exchange materials are potentially attractive for extraction of heavy metal cations from solutions. We have studied the time-dependent ion exchange activity of titanium phosphates for Zn2+, Co2+, and Ni2+ cations in relation to the liquid : solid ratio, temperature, and equilibrium pH of the cation exchange process. The results demonstrate that the selectivity of an ion exchanger for metal cations is determined by the ionic radii of the metals. Conditions for effective use of titanium phosphate materials for extraction of Zn2+, Co2+, and Ni2+ cations from solutions (liquid : solid ratio, temperature, and pH) have been optimized experimentally. [ABSTRACT FROM AUTHOR]

The results reported in this paper suggest that titanium(IV) oxyhydroxyphosphates can be used for sorption extraction of valuable metal cations from solutions, followed by desorption and concentration of the metal cations and simultaneous regeneration of the titanium phosphate material for further use. Conditions for effective desorption processes (desorbing agent concentration and desorption time) have been studied and optimized. The sorption/desorption process effectiveness in the case of multistep use of the sorbent has been shown to decline as a result of steric hindrances associated with its dehydration. As the sorption properties of the sorbent degrade, it can be used for extraction of trace amounts of highly toxic metal cations and then buried. [ABSTRACT FROM AUTHOR]

This paper demonstrates the feasibility of using titanium(IV) oxyhydroxyphosphate-based materials for sorption extraction of heavy metal cations from solutions. We have determined Pb2+ and Cd2+ sorption characteristics of ion exchangers, examined the kinetics of Pb2+ and Cd2+ sorption on the titanium phosphate materials, and assessed the effect of ionic radius on the affinity of the sorption matrices for metal cations. Conditions for effective use of the ion exchange materials for extracting Pb2+ and Cd2+ cations from solutions (liquid : solid ratio and pH) have been optimized experimentally. [ABSTRACT FROM AUTHOR]

Sorbents based on titanium(IV) compounds have been shown to be potentially attractive for quantitative removal of antimony(III) anions from liquid radioactive waste with complex chemical composition. Evidence is presented that titanium(IV) oxyhydroxyphosphates have enhanced affinity for antimony(III) cations. Selectivity of sorption matrices increases with increasing solution acidity and with an increase in the concentration of hydrogen phosphate groups in the composition of the material. Having enhanced affinity for negatively charged antimony(III) ions, titanium(IV) oxyhydroxides are potentially attractive for extraction of anionic species. [ABSTRACT FROM AUTHOR]

It has been demonstrated that titanyl hydrogen phosphate-based sorption materials can be effectively used for the extraction of cesium and strontium radionuclides from liquid radioactive waste similar in chemical composition to seawater. We have optimized conditions (pH, liquid : solid ratio, and temperature) for the coextraction of cesium and strontium cations. The titanium(IV) cesium or strontium double phosphate formed after heat treatment of the spent sorbent ensures proper immobilization of the radionuclides. [ABSTRACT FROM AUTHOR]

The stability of the LiCoPO4 electrode material in contact with a NASICON-type lithium ion conducting solid electrolyte having the composition Li1.5Al0.5Ge1.5(PO4)3 (LAGP) and a wide range of electrochemical stability has been studied for the first time. We have found the optimal temperature at which there is no reaction between the starting components of the composites and they retain their chemical and thermal stability. Cosintering a mechanical mixture of synthesized single-phase LiCoPO4 and LAGP powders with a submicron particle size at 750°C, we have obtained a stable LiCoPO4/LAGP two-phase composite whose room-temperature electrical conductivity is three orders of magnitude higher than that of the lithium cobalt double phosphate. Composites based on LiCoPO4 and the LAGP ionic conductor can be regarded as promising cathode materials for all-solid-state lithium ion batteries. [ABSTRACT FROM AUTHOR]

We have proposed compositions of titanyl hydrogen phosphate-based sorption materials modified with zirconium(IV) cations and containing both cation and anion exchange functional centers, represented by НРО and OH– groups, respectively. The synthesized materials were tested in sorption of antimony(III) cations and anions from high-salt solutions. Increasing the concentration of functional groups in ion exchange matrices has been shown to increase their affinity for antimony(III) ions. Such compositions can be regarded as promising ion exchange materials for efficient extraction of antimony radionuclides from multicomponent high-salt liquid radioactive waste. [ABSTRACT FROM AUTHOR]

We have studied the hydrolytic stability of titanyl hydrogen phosphates in relation to their composition, the synthesis procedure, and the nature and concentration of the electrolyte. The chemical stability of these compounds can be improved by increasing the electrolyte concentration and decreasing the degree of hydration of metal cations in solution and also by modifying their composition with metal cations differing in acid-base properties from titanium(IV). We have found conditions that maximize the hydrolytic stability of the titanyl hydrogen phosphates. [ABSTRACT FROM AUTHOR]