Flow-injection spectrophotometric determination of gold using 5-(4-sulphophenylazo)-8-aminoquinoline

摘要

Gold (0-75#mu#g ml~(-1)) was determined spectrophotometrically at 605 nm in a flow injection (FI) system based on the reaction of gold (III) and 5-(4-Sulphophenylazo)-8-aminoquinoline (SPA) in the presence of cetyltrimethylammonium, bromide (CTAB). The carrier stream was 1% (w/v) disodium ethylenediaminetetraacetate and the reagent streams were 2.0*10~(-4)M SPA and 0.6% (w/v) sodium hydroxide solution. The sample solution was mixecd with 0.2% (w/v) CTAB solution prior to injection. The various chemical and physical variables were optimised and a study of interfering ions was carried out. The relative slandard deviation for the determination of 5 #mu#g ml~(-1) gold was 0.9% (n=10) and the limit of detection (blank signal plus three times the standard deviation of the blank) was 1.1#mu#g ml~(-1),both based on injection volumes of 60#mu#l.The method has been successfully applied to the determination of gold in ores and anode slimes.