Salt effects on the surfactant-sensitized spectrophotometric determination of beryllium with Chrome Azurol S

Journal Article · Fri Jan 01 04:00:00 EST 1982 · Anal. Chem.; (United States)

DOI:https://doi.org/10.1021/ac00238a019· OSTI ID:6857404

Callahan, J H; Cook, K D

The effects of added electrolytes on the spectrophotometric determination of beryllium by absorbance of its complex with Chrome Azurol S (CAS) in the presence of aqueous hexadecyltrimethylammonium bromide (CTAB) were explored. The molar absorptivity increased with the addition of salt, in the order no salt < Na/sub 2/SO/sub 4/ < NaCl < NaBr less than or equal to NaNO/sub 3/. Variation of cation (Li/sup +/, Na/sup +/, K/sup +/, NH/sub 4//sup +/) of added chloride salts produced no effect lambda/sub max/ was red shifted 12-14 nm for all salts. The exact magnitude of this shift depended on beryllium concentration. Increasing the concentration of the added electrolyte resulted in increasing absorbances which leveled off at salt concentrations greater than 0.2 M. Thus, addition of salts at high concentrations swamped out their interferences and lowered the detection limit for the determination of beryllium by the surfactant-sensitized technique to 2.0 x 10/sup -7/ M. The results suggest that ion-exchange processes at the micellar surface may be involved in the mechanism of the salt effect.

• Research Organization: Univ. of Illinois, Urbana
• OSTI ID: 6857404
• Journal Information: Anal. Chem.; (United States), Journal Name: Anal. Chem.; (United States) Vol. 54:1; ISSN ANCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400104* -- Spectral Procedures-- (-1987)
ALKALI METAL COMPOUNDS
ALKALINE EARTH METALS
BERYLLIUM
BORIDES
BORON COMPOUNDS
CHLORIDES
CHLORINE COMPOUNDS
DATA
ELECTROLYTES
ELEMENTS
EXPERIMENTAL DATA
HALIDES
HALOGEN COMPOUNDS
INFORMATION
METALS
NITRATES
NITROGEN COMPOUNDS
NUMERICAL DATA
OXYGEN COMPOUNDS
SENSITIVITY
SODIUM BORIDES
SODIUM CHLORIDES
SODIUM COMPOUNDS
SODIUM NITRATES
SODIUM SULFATES
SPECTROPHOTOMETRY
SULFATES
SULFUR COMPOUNDS