Sorbitol and xylitol were used as raw materials for the preparation of heavier hydrocarbons byreduction with hydriodic acid under mild reaction conditions. The generated liquid hydrocarbons were analyzed by gas chromatography-mass spectrometry ( GC-MS ) and Fourier transform infrared spectroscopy ( FT-IR ) .Their physicochemical properties were further characterized. The heavier hydrocarbons obtained from sorbitol mainly include C12 H16 , C12 H18 , C12 H20 , C12 H22 and C18 H26 , with a yield of 85. 1%. In contrast, that prepared from xylitol were mainly composed of C10 and C15 hydrocarbons with a yield of 62. 8%. When using a mixture of sorbitol/xylitol ( 50 :50 ) as feedstock, C11 hydrocarbons were also generated besides C10 , C12 , C15 and C18 hydrocarbons. The yield of total heavier hydrocarbons was 65. 4%. To get purer liquid hydrocarbons, the obtained raw product was treated with potassium hydroxide in an ethyl alcohol solution, followed by rotary evaporation and vacuum distillation, and a liquid hydrocarbon fuel contains less than 0. 2% of water and 1. 8% ~2. 1% of oxygen was generated. Its kinematic viscosity is 3. 15~ 3. 17 mm2/s, density 0. 83~ 0. 84 g/mL, and calorific value greater than 43 MJ/kg at room temperature. The umpolung of the C-I bond and the intermolecularC C coupling may result in the formation of heavier hydrocarbons from polyols.%在较温和的条件下,山梨醇和木糖醇被氢碘酸还原转化为高碳烃液体燃料。产物采用 GC-MS 和 FT-IR 进行定量分析与表征,并对高碳烃产品的理化性质进行了测定。结果表明,以山梨醇为原料制备的高碳烃产物主要是包括 C12 H16、C 18、C12 H20、C12 H22和 C18 H26在内的烷烃、烯烃和芳香烃等化合物,烃类的总产率可达85.1%。以木糖醇为原料的反应过程与山梨醇相似,但所得高碳烃是以 C10和 C15为主的烃类化合物,产率为62.8%。实验还以质量分数为50%的山梨醇和50%的木糖醇混合物为原料制备了高碳烃,结果发现,产物中除 C10、C12、C15和 C18烃外,还有一定量的 C11烃生成,高碳烃产率为65.4%。反应产物经碱化、旋转蒸发和减压蒸馏后分离得到纯度较高的高碳烃,其含水量低于0.2%,常温下运动黏度为3.15~3.17 mm2/ s,密度为0.830~0.840 g/ mL,含氧量为1.8%~2.1%,热值高于43 MJ/ kg。高碳烃的生成是由于多元醇被还原过程中 C-I 键的极性反转和分子间 C-C 键的偶联导致。12 H
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