Off-line and on-line preconcentration of trace levels of beryllium using complexing agents with atomic spectrometric and fluorimetric detection

✍ Scribed by D.B.Do Nascimento; G. Schwedt

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 577 KB
• Volume: 283
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(93)85305-4

✦ Synopsis

Two methods were investigated for the determination of traces of beryllium. One was developed using polyethylene powder as an adsorbent for preconcentration of the stable complex formed between beryllium and Chrome Axurol S. After elution, the preeoncentrated metal was determined by graphite furnace atomic absorption spectrometry. With the analytical procedure developed for water analysis, detection limits of 0.8 fig l-', relative standard deviations of 254.1% and recoveries of 92-104% can be achieved for beryllium in tap water. In the other method, ion exchange was incorporated in a flow-injection system by using an ion-exchange micro&~ in the sample loop of a six-port valve. The effects of sampling time, eluent composition and concentration and sample acidity were investigated to develop a preconcentration procedure for the determination of beryllium in tap water using fluorimetric detection with morin reagent. The proposed method was characterized by a precision of about l.S%, a detection limit of 0.2 pg 1-l and recoveries of 95105%.