title: On-line column preconcentration for the determination of cobalt in sea water by flow-injection chemiluminescence detection.
abstract: 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.
authors.affiliation: Chugoku National Industrial Research Institute, 2-2-2 Hiro-suehiro Kure, 737-01, Hiroshima, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Hirata
authors.forename: Y
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: M
authors.initials: M
authors.lastname: Aihara
authors.forename: G V
authors.initials: GV
authors.lastname: Mallika