A porphyrin derivative from cardanol as a diesel fluorescent marker

A novel porphyrin fluorescent marker from a naturally occurring substance, cardanol, is presented. Synthetic routes were investigated to obtain an aldehyde precursor derived from cardanol and the target porphyrin; the conditions for porphyrin formation, choice of acid and reaction time were optimized. The resulting meso-tetrakis(2-methoxy-4-pentadecylphenyl)porphyrin exhibits high solubility in diesel fuel and its strong fluorescence was observed as two characteristic signals; the porphyrin marker was stable in diesel for at least 3 months. The physical properties of the diesel were unaffected by the presence of the porphyrinic marker at a concentration of 2 ppm.