On-line column preconcentration for the determination of cobalt in sea water by flow-injection chemiluminescence detection

• Published in: Analytical and bioanalytical chemistry Vol. 355; no. 5-6; pp. 676 - 679
• Main Authors: Hirata, S, Hashimoto, Y, Aihara, M, Mallika, G V
• Format: Journal Article
• Language: English
• Published: Germany 01.06.1996
• ISSN: 1618-2642; 1618-2650
• DOI: 10.1007/s0021663550676

A flow-injection method for the determination of dissolved cobalt(II) in sea water has been studied based on a combination of column preconcentration using 8-quinolinol immobilized on silica gel, fluoride containing metal alkoxide glass (8HQ-MAF) and chemiluminescence detection with a gallic acid-hydrogen peroxide system. Co(II) is selectively recovered from an acidified sample with 8-quinolinol immobilized on silica gel. After elution with dilute hydrochloric acid the resultant eluent is mixed with the reagent solutions, heated to 60 ( degrees )C and then introduced into the CL cell. The analysis time including the 2-min sample load was 8 min per sea water sample with a corresponding detection limit of 0.62 ng l(-1) (3sigma). The average standard deviation calculated for 10 replicate measurements of artificial sea water samples with a concentration of 10 ng l(-1) cobalt was +/-2.1%. The method has been tested with the standard reference sea waters NASS and CASS.