Preparing refractory oxides, silicates, and ceramic materials for analysis, by heating with acids in sealed tubes at elevated temperatures

Abstract

This paper describes t he preparation for analysis of a number of refrac tory oxides, ceramic materials, and m inera ls by decomposit ion wit h hydrochloric or bydriodic a.cid at t emperatures up to 300 0 C. All the oxides of the elements in the second, t hird, and fourth groups of the periodic syst em , with t he exception of silica, t itania, zirconia, a nd possibly hafnia, respond to the t reat ment. A number of silicate minerals, ordin arily difficult to prepa re for a nal ysis, are likewise successfully decomposed .

High-Precision, Simultaneous Analysis of Pt, Pd, and Rh in Catalytic Converter Samples by Carius Tube Dissolution and Inductively Coupled Plasma Atomic Emission Spectroscopy with Charge-Injection Device Detection

“…Table V illustrates the incomplete dissolution of matrix elements and Rh with 1 g of sample. Dissolution is incomplete because of increased concentrations of Ce, Ni, and Zr in the matrix, despite the fact that similar size samples of pure Ce and Zr oxides have been completely dissolved in aqua regia, 13 with results reproduced here for CeO 2 . Although the carius tube method had limited dissolution ability for the fresh converter sample, multiple 0.5 g samples can be dissolved and concentrated to the targeted Pt level.…”

“…Sam ples and standard were dissolved by using carius tube chlorination for dissolution of both matrix and noble m etals. 12,13,[16][17][18] Carius tubes were produced in-house by using CG-703-06 heavywalled glass tubing (Chemglass, Vineland, NJ), 29 cm in length, with 2.5 cm o.d. and 4 mm wall thickness.…”

“…12 Carius tubes have proven to be extremely effective for dissolving the wide variety of components found in catalytic converters, including noble m etals and oxides of Ce, Zr, and Ti. 13 When coupled with hydro uoric acid-perchloric acid treatment to remove silicon from the sample, carius tube chlorination can achieve complete dissolution of catalytic converter samples. This method was the primary dissolution method used by the National Institute of Standards and Technology (NIST) to certify catalytic converter standard reference materials (SR Ms) 2556 and 2557.…”

The determination of boron and lithium in nuclear materials by secondary ion mass spectrometry

“…This is somewhat surprising in the cases where the suspected molecule is known to be, chiral, for example, in the identification of drugs of abuse. A case in point is the fact that a legally permissible test for the natural or L isomer of cocaine is a microcrystalline test wherein recognition is made by microscopic examination (2). Since CD is a measure of the difference in absorption of left and right circularly polarized light, it is conceivable that the analytical potential of CD has not been developed because it was suspected that the same limitations inherent to absorption spectroscopy would exist;…”

The Determination of Sodium in Alumina. Part I. An Investigation of Suitable Fluxes for Dissolving Refractory High Purity Aluminas

“…In general, chemical methods for determining traces of alkalis in alumina have involved the following treatments: 1) acid extraction or leaching [5] 2) dissolution in acids at atmospheric pressure [6,7,9,10] 3) dissolution in acids under pressure [11,12] 4) sinters and fluxes. The most widely used method for the determination of soda in alumina is by acid extraction [5].…”