Aniline was chosen as an atmospheric pollutant which might be
monitored using an electrochemical sensor. The effect of pH and
of different organic solvents on electrode poisoning was
investigated for the analysis of aniline by voltammetry and it
was concluded that it was not possible to prevent poisoning of
the electrode by the reaction products. The analysis of aniline
by flow injection analysis (fia) with DC (constant potential)
and pulsed (double pulse) amperometric detection also suffered
from electrode poisoning and the latter had a relatively high
Secondary and tertiary substituted anilines with similar
volatilities to aniline at room temperature were examined as
suitable alternatives to aniline using voltammetry.
Dimethyl-p-toluidine poisoned the electrode to a small extent
when analysed by voltammetry. Detection of this compound by fia
with pulsed amperometric detection showed improved electrode
stability but was not judged suitable for long term monitoring
of atmospheric samples of the amine.
A satisfactory method for monitoring aniline on line was
developed using fia with triple pulse amperometric detection
(PAD). The PAD waveform was optimised with respect to a low
detection limit and a degree of selectivity towards possible
atmospheric interferents for the detection of aniline in dilute
aqueous acid at a platinum electrode.
A wall jet cell was designed for the analysis of aniline vapour
in air which was continuously trapped in dilute acid and
periodically injected into a fia system. The cell was not
affected by small gas bubbles and was reasonably portable [continued]...
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.