Flow injection sequential speciation of free and total potassium in fortified w...

• Author(s): Rangel, António O. S. S. ; Tóth, Ildikó V.
• Date: 1996
• Persistent ID: http://hdl.handle.net/10400.14/6091
• Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
• Subject(s): Flow injection; Potassium speciation; Wine; Potentiometry; Flame emission spectrometry
• Document Type: Article
• Language: English

Description

A flow injection system for the potassium speciation in fortified wines, using two detectors placed in series, is described. The free, or ionized form, is monitored in a tubular-shaped potassium ion-selective electrode, and the total potassium content in a flame emission spectrometer used as end-of-line detector. Potassium determinations can be carried out in a linear range from 300 to 2000 mg 1-1, with a sampling-rate of 60 samples per hour. The results obtained were comparable to the conventional procedures using the same detection systems, and the precision was good (relative standard deviations below 3.1%o for free potassium and 3.8% for total potassium).