Abstract Ketonization of biomass-derived oxygenates provides an efficient way for bio-oil upgrading. However, little information on the ketonization of oxygen-rich sugars has been reported, leaving the deep deoxygenation of biomass an unsolved challenge. To address the problem, this paper investigated the catalytic pyrolysis of xylose over nano-CeO2 using an analytical pyrolyzer. Results showed that upon the addition of CeO2, multi-functional oxygenated compounds from xylose pyrolysis were majorly reformed to mono-functional ketonic products, resulting in a 5-fold increase in peak area of ketones. Among them, acetone and 2-butanone presented the highest selectivity of 51% with the CeO2 to xylose ratio of 10:1 at the temperature of 600 °C. Meanwhile, the short-chain oxygenates, i.e. C2-C3 aldehydes and alcohols, had been converted into C3-C5 ketones, indicating an outstanding ability of chain-increasing over CeO2. Both the catalyst dosage and the pyrolysis temperature play a vital role during the ketonization process. The reaction mechanism was proposed according to the experimental results, in which three major reaction pathways were analyzed. This study demonstrates that ketonization of biomass-derived sugars is a promising method for oxygen removal and carbon chain increase, thus improving the bio-oil quality.

中文翻译：

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木糖在 CeO2 上的酮化以生产单功能酮

摘要 生物质衍生的含氧化合物的酮化为生物油升级提供了一种有效的方法。然而，关于富氧糖的酮化的报道很少，这使得生物质的深度脱氧成为一个悬而未决的挑战。为了解决这个问题，本文研究了使用分析热解器在纳米 CeO2 上催化热解木糖。结果表明，加入 CeO2 后，木糖热解的多功能含氧化合物主要转化为单功能酮产物，导致酮峰面积增加 5 倍。其中，丙酮和 2-丁酮在 600 °C 的温度下表现出最高的选择性，为 51%，CeO2 与木糖的比例为 10:1。同时，短链含氧化合物，即 C2-C3 醛和醇，已转化为 C3-C5 酮，表明与 CeO2 相比具有出色的增链能力。在酮化过程中，催化剂用量和热解温度都起着至关重要的作用。根据实验结果提出了反应机理，分析了三种主要的反应途径。该研究表明，生物质衍生糖的酮化是一种有前景的脱氧和碳链增加方法，从而提高生物油质量。