A　coulometric　detector　based　on　carbon　felt　as　working　electrode　has　been　designed.　Ascorbic　acid,　hydroquinone,　gallic　acid　and　sulfur　dioxide　were　used　as　electroactive　compounds　to　determine　the　electrochemical　characteristics　of　this　detector.　Phe　coulometric　conversion　efficiency,　selectivity,　linear　response　range,　detection　limit　and　mass　transfer　coefficient　were　investigated　in　order　to　use　the　detector　as　a　cleanup　device　in　a　flow　injection　system　with　dual-detector.　This　system　has　been　used　for　determination　of　sulfur　dioxide　in　wine,　and　the　results　are　compared　to　those　from　the　aspiration-oxidation　method.　(C)　2000　Elsevier　Science　B.V.　All　rights　reserved.