Voltammetric determination of antioxidant 4,4´-methylenebis(2,6-di-tert-butylphenol) in lubricating oils using gold disc electrode

Abstract

The method of voltammetric determination of 4,4´ methylenebis(2,6-di-tert-butylphenol) antioxidant using linear sweep voltammetry with gold working electrode was developed. Different supporting electrolytes were studied for the development of this methodology. The supporting electrolyte 0.05 mol L-1 of H2SO4 containing ethanol with 6.6 % toluene was selected as the suitable medium to ensure the sufficient solubility of analyte. In this work, the electrochemical behavior of the mentioned antioxidant was investigated, and different voltammetric techniques were compared. The developed method was purposed for determination of antioxidant in base oil. It was found that this matrix makes impossible the voltammetric determination of antioxidant using working gold electrode. It is necessary to realize the sample pretreatment using extraction process. The model samples of used base oil were extracted using ethanol. The electroanalytical method developed has enabled the determination of antioxidants in model and real samples with satisfactory results and good prospects for practical analysis.