Low-Temperature Thermal Decomposition of Sulfates to SO(2) for On-Line (34)S/(32)S Analysis

S Halas; J Szaran

doi:10.1021/ac9900174

Low-Temperature Thermal Decomposition of Sulfates to SO(2) for On-Line (34)S/(32)S Analysis

Anal Chem. 1999 Aug 1;71(15):3254-7. doi: 10.1021/ac9900174.

Authors

S Halas¹, J Szaran

Affiliation

¹ Mass Spectrometry Laboratory, Institute of Physics, Maria Curie-Sklodowska University, 20-031 Lublin, Poland.

PMID: 21662914
DOI: 10.1021/ac9900174

Abstract

We describe a fast, inexpensive, and safe method of direct SO(2) extraction from BaSO(4) for sulfur isotopic analysis by mass spectrometry. Only two reagents are used: (1) pure NaPO(3), which is mixed with BaSO(4) sample, and (2) Cu foil, from which reaction boats are manufactured. The extraction precedes in the Cu boat placed into a quartz tube connected to a vacuum line. The boat is heated to 650-700 °C while pure SO(2) produced is collected in a "cold finger". Reaction is complete in 7-10 min. We have proven by means of (18)O-enriched BaSO(4) specimens that the oxygen isotopic composition of the SO(2) is totally controlled by (18)O content in NaPO(3), when the weight ratio of the reagent to sample exceeds 6:1. The method described can be used for "on-line" SO(2) preparation for isotopic analysis.