Aminpentacyanoferrate as a carbon monoxide indicator

Carbon monoxide (CO) is a substance that can cause suffocation and death and one of its main sources is the emission of gases in the exhaust of motor vehicles, due to incomplete combustion. For this reason, several countries have important legislation on vehicular pollution. Several analytical techniques for determining CO are used; however, most of them are expensive or require qualified professionals. The purpose of this work was to use the aminpentacianoferrate complex in the development of a spectrophotometric methodology based on the exchange of ammonia ligand (NH3) by carbonyl (CO), with applicability in the rapid determination of carbon monoxide in vehicle emissions. The synthesized complex was characterized in terms of its structure and the analytical parameters were validated. The analytical curve was between 135 mg L-1 and 812 mg L-1, with R2 = 0.9965, with a repeatability of 4.6% and stability of the carbonylated complex of ± 1.0% in 15 minutes. This method was applied to samples of vehicle emission gas having low cost, being possible to use portable spectrophotometers of easy manipulation and access, for fast measurements.