Portal de Periódicos da CAPES

Artigo Acesso aberto Produção Nacional Revisado por pares

BIBTEX RIS

Sistema automático para determinação seqüencial de cianeto livre e total empregando eletrodo tubular íon-seletivo de membrana homogênea

2000; Brazilian Chemical Society; Volume: 23; Issue: 1 Linguagem: Inglês

10.1590/s0100-40422000000100006

1678-7064

Maria Angélica Bonadiman Marin, Reinaldo Carvalho da Silva, Arilson Lehmkuhl, José Bento Borba da Silva, Edgard Moreira Ganzarolli, Roldão Roosevelt Urzêdo de Queiróz,

Electrochemical Analysis and Applications

HOMOGENEOUS MEMBRANE TUBULAR ION-SELECTIVE ELECTRODE.This study presents an automated system for potentiometric determination of free and total cyanide which employs a homogeneous membrane tubular ion-selective electrode.After the electrode is assembled, it is connected to a system composed of 3 three-way solenoid valves, sample line, carrier line, acid stream, and gas diffusion chamber.A Turbo Pascal ® computer program, developed specifically for this task, automatically performs all the steps involved in data acquisition and processing.The proposed analytical procedure offers operational simplicity, since detection is performed by a tubular electrode, whose assembly is fast and easy.The system has shown reproducibility (r.s.d.< 0.5%, n=6) and high speed (30 readings/hour); it is efficient for determination of free and total cyanide in waste waters of starch processing plants.The detection limit was 1.2x10 -5 and 1.5x10 -5 mol L -1 , for determination of free and total cyanide, respectively.The linear response range was between 1.2x10 -5 and 1.0x10 -2 mol L -1 for free cyanide and between 1.5x10 -5 and 1.0x10 -2 for total cyanide.