【作者】 武立斌；

【导师】 杨正宇；

【作者基本信息】 中国科学院研究生院（理化技术研究所） ， 物理化学， 2009， 博士

【摘要】 生物质是一种含氧燃料,来源丰富,可再生,如果将其转化并应用在内燃机上,不仅可以减少汽车工业对石油的依赖,还可以减缓温室气体CO₂的排放,因此越来越多地受到人们的重视。生物质热解液体亦称生物油,是用传统热解过程产生的气体经冷凝得到的一种含氧量较高的液体,氧含量通常为35～45%,其中以水的形式存在的氧元素占很高比例,其它形式主要有羟醛类、羟酮类、糖类、羧酸和酚类等物质。这些物质的存在使得生物油在取代传统的化石类燃料受到了很大的限制,而且后续处理非常困难。本课题创新性地在不外加氢的条件下,利用直接脱氧液化工艺,将生物质转化为高热值的液体燃料。具体工作如下:在一定条件下,对四种类型共计十八种生物质进行直接脱氧液化,结果显示树叶样品所得油中烷烃和芳烃成分所占比例非常高,其中杨树叶和桦树叶油中烷烃和芳烃的总含量分别高达60.01%和57.86%,H/C摩尔比分别为1.79和1.89,O/C摩尔比分别为0.035和0.036,热值分别为45.47 MJ·kg⁹（-1）和46.03 MJ·kg^-1。这些数据显示所用树叶所得油已经与矿产石油非常相似。树皮样品所得油中碳氢化合物成分总含量有所降低,油的热值也有所降低,大体在40MJ·kg^-1左右,但是在树皮所得油中出现了大量的酚类物质,百分含量在40%左右。酚类是重要的化工产品,在工农业领域有着广泛的用途,因此树皮所得油通过精制,既可得到液体燃油又可得到酚类化学品。木屑所得油中富含酚类化学品而烷烃和芳烃等碳氢化合物成分含量非常少,酚类化学品的种类接近30种,且总含量高达60%。对青草进行了脱氧液化实验,虽然青草所得油的产率以及热值方面,都与树叶所得油相似,但不足之处是油中含有大量的含氮化合物,这对油的进一步精制中氮的去除增加了不少难度。在杨树叶、杨树皮和杨树木屑单独对比方面,杨树叶中表面活性剂提取物最多,杨树木屑中提取物最少;而木质素含量则正好相反,杨树木屑中木质素含量最多,杨树叶中木质素含量最少。在产物分布方面,杨树叶产油量最高,杨树木屑产油最低,杨树皮在两者之间。在产生气体的元素组成方面,杨树叶所产气体中含有较多的氧元素和较少的氢元素,而由杨树皮和杨树木屑所产生的气体中含有的氧元素逐步降低,氢元素逐步升高。气体中氧的增加可以使油中的氧含量降低。在所得油的成分方面,树叶所得油中含有非常多的烷烃和芳烃等碳氢化合物而含有少量的酚类物质,杨树木屑所得油中含有非常多的酚类物质而含有非常少的碳氢化合物,杨树皮居于两者之间。因此得出结论:原料中含有的表面活性剂提取物越多,则得到的油中烷烃和芳烃等碳氢化合物含量就越多;原料中含有的木质素越多,则所得油中酚类物质就越多。综上所述,林业生物质通过直接脱氧液化方法,不仅可以制取车用汽柴油,也可制取酚类化学品,其中树叶和青草通过脱氧液化后,所得油适合于精制为车用汽柴油,树皮和木屑通过脱氧液化后,所得油适合于精制成酚类化学品。更多还原

【Abstract】 Biomasses were renewable oxygen-containing fuel. If it was converted and applied in internal combustion engine, not only reduce the dependence of automobile industry on petroleum, but also slow down the emissions of CO₂ greenhouse gases. The pyrolysis liquids from biomass also called bio-oil were obtained through the traditional pyrolysis process. And the oxygen content in it was usually 35-45% which existed in the form of water and other forms such as aldehydes, ketones, sugars, carboxylic acids, phenols. The existence of these substances made it difficult for the bio-oil in place of the traditional fossil fuels. Our research group has developed an innovative technological route in which biomass can be converted into the carbon-hydrogen liquid fuel with high heating value by direct deoxy-liquefaction in the absence of hydrogen. The detailed studies were as follow:Under certain conditions, 18 kinds of samples were experimented. Results showed that oils from the leaves rich in alkanes and aromatics. The total content of alkanes and aromatics were up to 60.01% 57.86% for poplar leaves and birch leaves with H/C molar ratio 1.79 and 1.89, O/C molar ratio 0.035 and 0.036, and HHV 45.47 MJ·kg^-1and 46.03 MJ·kg^-1These data shows that the oil from leaves was very similar to petroleum. The hydrocarbon content in oil from bark were decreased and then the HHV about 40 MJ·kg^-1A large number of phenolics were found and the content was up to about 40%. The oil obtained from wood was rich in phenolics but poor in hydrocarbons. The kind of phenolics was about 30 species, and the total content of them were up to 60%. The oil obtained from grass was similar to that of leaves but the inadequacies of the oil was large amounts of nitrogen-containing compounds were found, which was difficult to refined.Among the poplar leaf, bark and wood, the poplar leaf rich in surfactant extract, while extracts in poplar wood was poor. On the contrary, lignin content was very high in poplar wood but poor in poplar leaves. As for product distribution, the oil yield of leaves was higher than that of poplar bark and poplar wood. In regard to the composition of gas product, gas from leaves contain more oxygen and less hydrogen element. For the gas from poplar bark and wood, the oxygen contained in gradually reducing and hydrogen elements in the progressive rise. The increase of oxygen content in gas can reduce the oxygen content in the oil. The oil from leaves contains a large number of hydrocarbons and contains small amounts of phenolics but oil from poplar wood contains a lot of phenolics and little hydrocarbons. The bark was moderate. Therefore we can conclude: more surfactant extract contained in raw materials more hydrocarbon content in oil.In summary, forestry biomass can not only be converted to gasoline and diesel, but also to phenolics by direct deoxy-liquefaction method. Leaves and grass were suitable converted to gasoline and diesel. Bark and wood were suitable converted to phenolics by direct deoxy-liquefaction.更多还原