The influence of organometallic additive in gasoline on the exhaust gas aftertreatment components

As a rule, metal containing additives are not used in fuel in the European Union. A limit of up to 6 mg of manganese per liter of gasoline was introduced in the revised Fuel Quality Directive in 2011. In this paper, the influence and risk of metal containing additives on the aging of exhaust system components over full useful life of 160,000 km is verified, using the example of an additive containing 6 mg of manganese per liter as a basis. The investigations were carried out on a certified roller dynamometer by means of two endurance tests with vehicles running on metal-free fuel and fuel containing metal. Both vehicles were equipped with a typical state-of-the-art downsizing gasoline engine with a Euro 5 application. Euro 5 reference fuel was used as the basis for gasoline. The exhaust emissions were analyzed at fixed intervals over the endurance run. In order to a better understanding of the NEDC emissions results, the characterization of the exhaust system was supported by measurements of the oxygen storage capacity (OSC), an endoscopy and a computed tomography of the catalytic converter. The results of the investigations are presented and discussed. It is shown that the increasingly strict emission limits require improved fuel grades. Using metal containing additives in fuel poses a risk to modern engines and highly efficient exhaust aftertreatment systems and therefore also to the environment.