Oxidation of petroleum asphaltenes by potassium iodide (KI) is described. Oxidation under mild conditions is shown to be accompanied by iodination of the asphaltene aromatic core. The inducing reaction is the oxidation of sulfide sulfur atoms in the asphaltenes with reduction of iodate anion to molecular iodine; the coupled reaction, electrophilic substitution. X-ray photoelectron spectroscopy detected an increase in the mass fraction of oxygen as compared with the initial sample and formation of C–I bonds. IR spectroscopy found that oxidation of the asphaltenes is accompanied by the formation of carboxyl and sulfoxide groups. Raman spectroscopy revealed a decrease in the size of the oxidized asphaltene molecules as compared to the native asphaltenes. X-ray powder diffraction analysis showed a decrease in the interplanar spacing of the asphaltene oxidation product that was due to ordering and a denser arrangement of the aliphatic fragments.

中文翻译：

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石油沥青的氧化与碘化相结合

描述了用碘化钾 (KI) 氧化石油沥青质。显示温和条件下的氧化伴随着沥青质芳香核的碘化。诱导反应是沥青质中的硫化物硫原子氧化，碘酸盐阴离子还原为分子碘；偶联反应，亲电取代。X 射线光电子能谱检测到与初始样品相比氧的质量分数增加并形成 C-I 键。红外光谱发现沥青质的氧化伴随着羧基和亚砜基团的形成。拉曼光谱显示与天然沥青质相比，氧化沥青质分子的尺寸减小。