Antioxidant potential of sulfenimides in waste walnut oil biodiesel: kinetic stability, phosphomolybdenum activity, and reducing power capacity
Yazarlar (6)
Öğr. Gör. Nalan Türköz Karakullukçu Ondokuz Mayıs Üniversitesi, Türkiye
Doç. Dr. Hasan Yakan Ondokuz Mayıs Üniversitesi, Türkiye
Öğr. Gör. Volkan Murat Yılmaz Bartin Üniversitesi, Türkiye
Prof. Dr. Halit MUĞLU Kastamonu Üniversitesi, Türkiye
Semiha Yenigün
Ondokuz Mayis Üniversitesi, Türkiye
Halil Kütük Ondokuz Mayis Üniversitesi, Türkiye
Makale Türü Açık Erişim Özgün Makale (SSCI, AHCI, SCI, SCI-Exp dergilerinde yayınlanan tam makale)
Dergi Adı Turkish Journal of Chemistry
Dergi ISSN 1300-0527 Wos Dergi Scopus Dergi
Dergi Tarandığı Indeksler SCI-Expanded
Makale Dili İngilizce Basım Tarihi 01-2026
Cilt / Sayı / Sayfa 50 / 1 / 21–37 DOI 10.55730/1300-0527.3777
Makale Linki https://doi.org/10.55730/1300-0527.3777
Özet
This study investigated the influence of synthetic sulfenimides on biodiesel–diesel fuel blends. Three previously synthesized sulfenimide derivatives were structurally characterized using spectroscopic techniques. We evaluated their antioxidant properties through phosphomolybdenum activity and reducing power capacity assays. The tested fuel samples were designated as D100, B10D90, B10D90_AA (ascorbic acid), B10D90_3, B10D90_2, and B10D90_1. The effect of adding 2000 ppm of the additive was measured using an Oxifast instrument following the ASTM D7545 standard, and the results were compared to those of the chemical antioxidant ascorbic acid. Inhibition time values were derived from the oxidation stability results. The starting temperatures for crystallization (Tc) of the mixtures were found using differential scanning calorimetry (DSC), and the measured temperatures were –7.24, –7.64, –7.89, –8.06, –8.39, and –8.52 °C. FT-IR spectra exhibited characteristic absorption bands associated with antioxidant functional groups, which means the sulfenimide compounds were successfully added. The addition of sulfenimides improved the oxidative stability of biodiesel blends. Furthermore, we conducted thermogravimetric analysis (TGA) at multiple heating rates to investigate the thermal decomposition kinetics of the sulfenimides. The activation energies for compounds 1, 2, and 3 were calculated using the Kissinger– Akahira–Sunose (KAS) method and were found to be 125.28, 111.34, and 88.11 kJ mol ¹, respectively.
Anahtar Kelimeler
antioxidant | biodiesel | inhibitory effect | kinetic study | Sulfenimides