%0 Journal Article
%T Evaluation study of an ion selective field effect transistor electrode for measuring quality parameters of fuel ethanol
%A Gonzaga
%A Fabiano B.
%A Sobral
%A Sidney P.
%A Ribeiro
%A Carla M.
%A Gon£¿alves
%A Mary A.
%J Journal of the Brazilian Chemical Society
%D 2013
%I Sociedade Brasileira de Qu¨ªmica, SBQ
%R 10.1590/S0103-50532013000100008
%X an ion selective field effect transistor (isfet) electrode was evaluated for measuring ph and acid number (an) of fuel ethanol and compared to two glass electrodes with different reference filling solutions: kcl aqueous solution (glass-kcl electrode) and licl ethanolic solution (glass-licl electrode). ph was determined at different measurement times and an was determined using automatic potentiometric titration. for ph, the glass-kcl electrode showed the best precision and stability, with an average repeatability about four times better when compared to the isfet electrode for the measurement time of 30 s (as indicated in the astm d6423 standard). for an, the glass-kcl and glass-licl electrodes showed similar repeatabilities, which were about three times better than that of the isfet electrode. in addition, the results from a recovery study demonstrated better accuracy of the glass-licl electrode, with a recovery value of 100.1%.
%K isfet electrode
%K glass electrode
%K fuel ethanol
%K acid number
%K ph.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0103-50532013000100008&lng=en&nrm=iso&tlng=en