Thiosulfate adsorption on 304 and 316 stainless steels: An electrochemical, radiochemical and surface analysis approach

Conference · Tue Oct 01 04:00:00 EDT 1996

OSTI ID:369983

Thomas, A E; Kolics, A; Wieckowski, A ^[1]

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1. Univ. of Illinois, Urbana, IL (United States)

Thiosulfate adsorption on 304 and 316 stainless steels in mu neutral (pH {approximately}5.6) sodium perchlorate solution using radiochemical and electrochemical techniques as well as AES and YPS spectroscopies will be discussed. Thiosulfate adsorption occurs over a broad electrode potential range (-1.7 V to 1.2 V). In a Perchlorate environment, thiosulfate accumulation on 304 stainless steel was observed to be irreversible and is attributed to thiosulfate accumulation in the passive film, as indicated by AES and XPS data. Addition of chloride ions has little effect on thiosulfate surface concentration on 304 stainless steel below 10{sup -3} M suggesting that thiosulfate adsorbed more strongly than chloride. Above this concentration, thiosulfate is either increasingly desorbed (at -0.6 V) or accumulated (at -1.7 V) on 304 stainless steel. Contrarily, on 316 stainless steel, thiosulfate adsorption versus varying bulk chloride concentration initially increased with increasing bulk chloride concentration, reached a maximum at 10{sup -4}-10{sup -5} M Cl{sup -}, and decreased when more chloride was added. The contrasting adsorption behavior of thiosulfate on 304 and 3l6 stainless steel is due to the different molybdenum content (304, 0.75% Mo; 316, 2.5% Mo) of the two steels.

• OSTI ID: 369983
• Report Number(s): CONF-960376--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ADSORPTION
METALLURGICAL EFFECTS
MOLYBDENUM
STAINLESS STEEL-304
STAINLESS STEEL-316
SURFACE PROPERTIES
THIOSULFATES