Antioxidative efficiency of novel β-naphthol derivatives in storage assays of cracked naphtha

The types of hydrocarbons found in gasoline have great influence on the formation of gum (nonvolatile, insoluble, adhesive resin that forms sediments within fuel systems of an engine). In this study, the synthetic compound β-naphthol has been used in order to generate novel antioxidative substances: AO1 [6-N-ethyl,N-ethylamino)β-naphthol], AO2 [6-N-ethyl,N-diethylamino)-β-naphthol] and AO3 [mixture of amino-β-naphthol and 1,6-di-amino-β-naphthol]. The derived compounds were subjected to accelerated oxidative stability assays [potential gum (PG) and induction period (IP)] and to storage assays [washed gum (WG) and ASTM color] during six months with cracked naphtha provided by the petroleum refinery RPBC (Presidente Bernardes Refinery, in Cubatão, Brazil). During the PG and IP assays, the experimental amine mixture AO3 and the commercial product known as PDE were highlighted as good oxidation inhibitors, yielding average values of 39.15 mg/100 ml and 637 min, respectively. After the storage period, a better antioxidant behavior was observed for the experimental compound AO2, which provided an average WG value of 6.1 mg/100 ml.