生物质水热多相态转化为高级醇燃料的限域强化机制研究

Higher alcohol is the important alternative clean fuels for aviation, ship and vehicle. How to convert biomass to higher alcohol with low cost and high efficiency is the key problem. In this project, according to the properties (high oxygen content, hydrophilicity, heat sensitivity and complicated structure) of sugar (energy carrier molecule) derived from biomass hydrothermal decomposition, the ultra-stable and bi-functional two-dimension confined nano-carbon mass transfer channel is designed and prepared based on the strategy of molecule structure induced diffusion - selective structure transformation. The mechanism of confined enhancement on multiphase hydrothermal conversion of biomass to higher alcohol fuels is investigated. At the molecular scale, the diffusion transport and selective structure transformation of sugar（energy carrier molecule）to higher alcohol are enhanced by the same origin effect between wall of mass transfer channel and sugar, the effect of confinement and selective structure transformation of channel structure and size. At the macro scale, the adjustment of multiphase and heat transfer of self-rewetting fluid are investigated to prohibit local hot spot in the reactor, weaken the sorption of water molecule and enhance the diffusion of energy carrier molecule and desorption of higher alcohol in the two-dimension confined nano-carbon mass transfer channel. These works will promote the biomass conversion to higher alcohol with high selectivity and efficiency, which can provide the theory and technology support for large scale application of alternative clean fuels in the transportation area.

高级醇是航空、舰船及大型动力交通工具的重要清洁替代燃料，而如何实现生物质低成本高效转化为高级醇燃料成为急需解决的关键难点问题。本项目针对生物质水热解聚糖-载能分子含氧、亲水、热敏及构型复杂的特点，提出基于分子构型诱导扩散-择型转化的策略，构筑高水热稳定的功能化二维限域碳纳米传质通道，开展生物质水热转化为高级醇过程的传递-反应耦合限域强化机制研究。在分子尺度上，基于传质通道壁面与糖-载能分子的同源（糖源）效应、传质通道结构与尺度的限域与择型效应，强化糖-载能分子扩散输运传质、择型定向演变为高级醇。在宏尺度上，通过过程多相态调控和多孔催化颗粒表面自润湿沸腾传热，抑制反应器内局部高温热点、弱化二维限域碳纳米传质通道内水分子占位、强化载能分子传递输运和高级醇脱附，实现生物质高效定向转化为C5/C6高级醇，为促进航空、舰船及大型动力交通领域清洁替代燃料的规模化应用，提供理论与技术支撑。

高级醇是航空、舰船及大型动力交通工具的重要清洁替代燃料，实现生物质低成本高效转化为高级醇燃料具有重要应用意义。本项目针对生物质水热解聚糖-载能分子含氧、亲水、热敏及构型复杂的特点，开展了生物质水热转化为高级醇过程的传递-反应耦合限域强化机制研究。基于分子构型诱导扩散-择型转化的策略，设计构筑了高水热稳定的限域纳米传质通道的Mo/C基催化体系，强化糖-载能分子扩散输运传质、择型定向演变为高级醇，抑制高稳中间物形成，避免载能体分子深度脱氢，揭示了糖醇向高级醇分子定向演变机制。率先开发了生物乙醇载能体水热重构增碳合成高级醇燃料化学品技术路线，构筑催化剂LDHs/C二维两亲设计增强多相态间传递输运，高效移除反应器内局部高温热点，调控关键醛中间体分子在催化剂活性中心脱附，实现了高级醇的定向选择性调控。取得了生物质糖醇分子定向转化为C5/6高级醇选择性达72.9%、生物质乙醇水相偶联合成C4+高级醇收率49.3%等技术突破，形成了生物质高效定向转化为高级醇及柴油机应用的理论与技术基础。本项目已发表学术期刊论文18篇，申请发明专利16项，其中4项授权，培养了青年骨干人才3人，研究生6名。