Yu. A. Karpov

Determination of platinum and palladium in dead catalysts using inductively coupled plasma atomic emission spectrometry after sample digestion by high-temperature fusion

A technique for the determination of platinum and palladium in dead catalysts using ICP-AES after sample digestion by high-temperature fusion with potassium pyrosulfate is described. The technique is universal; it offers the possibility to analyze various brands of catalysts and their mixtures at a content of platinum and palladium of 0.1% to whole units of percent in a short time. The accuracy of results of determination of platinum and palladium is confirmed by comparison with the data of interlaboratory control. The relative standard deviation in the developed technique is 4–2.5% for the content of platinum and palladium of 0.1 to 0.5% and 2–1% for higher concentrations of these elements.

Determination of fluorine in inorganic substances (Overview)

This is a review of physical and chemical methods of determination of fluorine in inorganic substances which have been published in the last decade. Promising new indirect variants of molecular absorption spectrometry are presented, as well as widely applied methods of ion chromatography, potentiometry with fluoride selective electrode, and others.

Chemical preparation of samples of dead automobile catalyzers for subsequent determination of platinum, palladium, and rhodium using atomic emission spectrometry with inductively coupled plasma

Systematic studies of different methods for decomposition of samples of dead automobile catalyzers (ACs) on a ceramic base using mixtures of mineral acids and high-temperature alloying with the aim of subsequent determination of platinum, palladium, and rhodium using atomic emission spectrometry with inductively coupled plasma are presented. The behavior of matrix components of dead ACs under the conditions of sample decomposition is investigated. The effect of the results of determining platinum group metals is studied. The relative standard deviation of the results of the analysis performed according to the developed techniques is 11-9% at platinum, palladium, and rhodium concentrations ranging from 0.01 to 0.3%.

Direct atomic-absorption determination of platinum, palladium, and rhodium in dead ceramic-based autocatalysts

The data on the effect of different concentrations of components of dead automobile catalysts on determination of platinum, palladium, and rhodium using the method of ETAAS are obtained and systematized. The conditions for direct atomic-absorption determination of Pt, Pd, and Rh are optimized. The technique of atomic-absorption determination of PM in secondary raw and technogenic materials is developed (n × 10−4−n × 10−1 wt %, sr = 0.12–0.07).

Sorption-atomic-absorption determination of platinum, palladium, and rhodium in dead autocatalysts

The conditions for determination and group concentration of platinum metals (PMs) in the presence of matrix components using new S,N-containing complex-forming sorbents in solutions obtained after decomposition of decontaminated autocatalysts are proposed. The technique of atomic-absorption determination of PMs from a solution (n × 10−4−n × 10−2; sr = 0.15–0.07) and a solid phase (n × 10−5−n × 10−4; sr= 0.20–0.12) is developed.

Sorption recovery of platinum(II) and platinum(IV) chloro complexes with a heterochain sulfur-containing sorbent

The recovery of platinum(II) and platinum(IV) chloro complexes from hydrochloric acid and chloride solutions with a new heterochain S,N-containing sorbent, MITKhAT, was studied. The suggested mechanism of formation of platinum(II) mercapto-thio ether complexes in the course of sorption was confirmed by DFT calculations. The results of group and selective recovery of platinum metals with MITKhAT sorbent from simulated and real industrial solutions are reported.

Extraction of iridium(III) and iridium(IV) chloride complexes by a new sorbent containing sulfur and nitrogen

Sorption of iridium(III) and iridium(IV) chloride complexes from hydrochloric acid and chloride solutions by a sorbent MITKhAT containing sulfur and nitrogen is studied. Kinetic and sorption capacity of the sorbent depending on the composition of a solution and the oxidation state of iridium are determined. The most probable mechanism of sorption and the composition of an iridium complex formed are proposed.

Modern methods of autoclave sample preparation in chemical analysis of substances and materials

The importance of autoclave sample preparation in modern analytical control is shown. Spheres of application of resistive and microwave autoclave systems are distinguished. Resistive systems are recommended for multistage sample preparation including destruction, disintegration, concentrating, etc. A set of highly sensitive combined techniques is developed for analysis with autoclave sample preparation of high-purity substances: rare refractory, rare-earth, precious, and nonferrous metals; oxides and salts of these metals, alloys; semiconductor materials; glass and ceramics; mineral raw materials; objects of geochemistry and geology; ore-, coal-, and oil-refining industry; textile and light industry; objects of the environment, soils, foodstuffs, and agricultural production; sources for drugs and medical and cosmetic preparations.

Determination of selenium and cadmium dopants in nanocomposites based on zinc and indium oxides by high resolution continuous source electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry

An approach is proposed to the determination of selenium and cadmium dopants in new nanocomposites based on zinc and indium oxides. The approach is based on a combination of highly efficient high resolution continuous source electrothermal atomic absorption spectrometry (ETAAS) for the analysis of suspensions and inductively coupled plasma mass spectrometry for the analysis of solutions. A procedure is developed for the determination of Se and Cd dopants and matrix components based on Zn and In in nanocomposite solutions by inductively coupled plasma mass spectrometry. Stabilizing agents for the preparation of suspensions are studied for the ETAAS analysis of powders without their decomposition. The results of determination of CdSe dopants by high resolution ETAAS are validated by inductively coupled plasma mass spectrometry.

Decomposition of samples of used ceramic-based automotive catalytic converters in analytical autoclaves with resistive heating

Different ways of chemical sample preparation of used automotive catalytic converters (ACCs) in analytical autoclaves with resistive heating are studied for subsequent determination of platinum, palladium, and rhodium by AES-ICP. Conditions of autoclave decomposition of ACCs samples using binary mixtures of HCl-HNO3 and HCl-H2O2 that allow achieving quantitative extraction of platinum group metals into a solution without complete decomposition of the sample are determined. Universal methods of analysis of used ceramic-based automotive catalytic converters are developed. The relative standard deviation of the analysis results according to the developed techniques is 11-5% rel. at contents of platinum, palladium, and rhodium from 0.03% to 0.3%.