Synthesis and characterization of novel phenolic derivatives with the glycerol ketal group as an efficient antioxidant for gasoline stabilization

Abstract

The development of antioxidants with phenol, hydroxyl, and ketal functional groups provides a creative approach to preventing the degradation of stored petroleum-derived products such as gasoline. The present study proposes a simple and efficient protocol for successful synthesis of improved phenolic derivatives in good yields. The novel antioxidants were characterized via nuclear magnetic resonance (¹H NMR, ¹³C NMR, and DEPT 135°), elemental analysis, thermogravimetry (TG), and derivative thermogravimetry (DTG). TG/DTG curves show that 2,6-di-t-butyl-4-(2-(4-(hydroxymethyl)-2-methyl-1,3-dioxolan-2-yl)ethyl)phenol possesses a higher thermal degradation temperature (298 °C) than 2,6-di-t-butyl-4-methylphenol (BHT). The novel phenolic derivative with the glycerol ketal group was submitted for accelerated oxidation and induction period tests. The synthesized additive gave the best performance at 10 ppm concentration, which increases the induction period to 185 min. In the accelerated oxidation test, the carbonyl and peroxide band areas declined with the addition of 1% antioxidant to gasoline. The results revealed a significant reduction in the formation of oxidation products in gasoline at low concentration of the proposed antioxidants.