还原态铁氧化物对重质生物油的提质改性

以生物质热解获得的重质生物油作为研究对象，将铁氧化物负载到硅氧纤维上制备了复合铁基载氧体，以其还原态对重质生物油进行脱氧改性，反应条件为温度350 ℃、压力1.48 MPa。通过比较部分脱氧反应前后的重质生物油及载氧体组成和结构的变化，发现重质生物油组分中的氧元素被部分转移至载氧体中，重质生物油中氧元素质量分数由29.83%降低至26.12%，还原态载氧体(Fe₃O₄/FeO)被氧化为Fe₃O₄；计算得到重质生物油的有效氢/碳摩尔比由0.67增加至0.80，增加近18.44%，其热值增加至27.6 MJ/kg；组分中繁杂的有机组分大多缩合为羧酸和酚类，酮、醛类物质大幅度降低，碳氢化合物明显增多；继而添加乙醇进行催化酯化反应，则重质生物油中主要组分变为脂类和酚类，油品质有了明显改善。而复合于硅氧纤维的铁载氧体，再还原后结构稳定，可用于油品部分脱氧的多次循环。

Improvement and Modification of Heavy Bio-oil by Reduced Iron Oxide

The heavy bio-oil obtained by biomass pyrolysis was taken as the research object, and iron oxide was loaded to silica fiber to prepare composite iron based oxygen carrier to deoxidize and modify the heavy bio-oil at its reduced state under the reaction conditions of 350 ℃ and 1.48 MPa. By comparing the changes in the composition and structure of the heavy bio-oil and oxygen carrier before and after partial deoxidation, it was found that the oxygen element in the heavy bio-oil was partially transferred to the oxygen carrier, the mass fraction of oxygen element in the oil decreased from 29.83% to 26.12%, and the reduced oxygen carrier (Fe₃O₄/FeO) was oxidized to Fe₃O₄; the effective hydrogen/carbon molar ratio of the heavy bio-oil obtained by calculation increased from 0.67 to 0.80 by nearly 18.44%, and its calorific value increased to 27.6 MJ/kg; most of the complex organic components in the composition were condensed into carboxylic acids and phenols, ketones and aldehydes decreased obviously, while hydrocarbons increased significantly; ethanol was later added for catalytic esterification, as a result of which lipids and phenols became the main components in the heavy bio-oil, and the oil quality was obviously improved. In addition, the oxygen carrier compound with silica fiber has stable structure after reduction and can be used for multi-cycle partial deoxidation of the oil.