CBET: A two step chemocatalytic conversion of cellulosic biomass to hydrocarbon biofuels

我国经济的长期安全需要有一系列国内原料来生产燃料和化学品。生物质是一个很有前途的选择；然而，仍然需要可靠、可复制和经济的转换技术。该项目涉及支持转化技术的基础知识，该技术使用的资源仅针对燃料生产。该项目致力于将木质纤维素生物质直接转化为生物油，这种生物油有可能成为汽油和其他燃料的替代品。这些燃料将适用于目前的汽车内燃机和航空运输。该项目研究了一种新型催化剂，该催化剂具有三种功能，可以将纤维素、半纤维素和木质素的生物质结构分解成更小的化学实体，然后转化为燃料混合物。催化剂混合物是可回收的，并且易于从产品混合物中回收。潜在的节省是在一个更简单的两步工艺中获得的，催化剂的回收，以及从原料中获得更高的产品收率。由此产生的产品将是稳定的，并且具有高能量含量，可以混合到现有的燃料库存中。该项目的教育活动强调本科研究，并向高中生推广参与STEM职业。该项目的目标是研究一种节能可回收的两步催化过程，将生物质转化为下一代碳氢化合物生物燃料。这一目标将通过设计一种可回收催化剂来实现，该催化剂可以在单一反应器中在温和条件下从木质纤维素生物质中生产C5-C20范围的部分氧化的呋喃烯烃型生物原油。在第一步转化中，生物质中的纤维素和半纤维素在酸性离子液体催化下在较低温度下解聚成葡萄糖和木糖。在下一阶段，催化剂将单糖脱水成呋喃混合物，5-羟甲基糠醛和糠醛。在最后的反应步骤中，呋喃醛将在介质中与丙酮进行酸催化醛醇缩合。该复合产品将由C5-C20范围的化合物组成，这些化合物是由生物质衍生的呋喃和丙酮之间的交叉醛醇缩合产生的，以及丙酮自缩合产物。通过这种催化过程生产的生物原油是稳定的，由定义明确的稳定的呋喃烯烃和烯酮产品组成，然后使用既定的催化还原技术将其升级为碳氢化合物。

The long-term security of our economy requires a portfolio of domestic feedstocks to produce fuels and chemicals. Biomass is a promising choice; however, conversion technologies that are reliable, reproducible and economic are still needed. This project addresses fundamental knowledge supporting a conversion technology uses resources that are targeted solely for fuels production. This project addresses direct conversion of lignocellulosic biomass into a bio-oil that has the potential to be a drop-in replacement for gasoline and other fuels. These fuels would be applicable in current automotive internal combustion engines and for air transportation. The project researches a novel catalyst that serves three functions to break up the biomass structure of cellulose, hemicellulose, and lignin into smaller chemical entities that are converted into a fuel mixture. The catalyst mixture is recyclable and readily recovered from the product mixture. Potential savings are gained in a simpler 2-step process, recycling of catalyst, and higher yield of product from the feedstock. The resulting product would be stable and have high energy content to mix into existing fuel stockpiles. The project's educational activities stress undergraduate research and outreach to high school students for participation in STEM careers.The objective of the project is to research an energy efficient recyclable two step catalytic process for the transformation of biomass to next generation hydrocarbon biofuels. This goal will be achieved by the design of a recyclable catalyst that can produce C5-C20 range partially oxygenated furanic alkene type biocrude oil from lignocellulosic biomass in a single reactor operation under mild conditions. In the first conversion step, cellulose and hemicelluloses in the biomass undergoes an acidic ionic liquid catalyzed depolymerization to glucose and xylose at a relatively low temperature. In the next stage the catalyst will dehydrate the monosaccharides into a furan mixture, 5-hydroxymethylfurfural and furfural. In the final reaction step, the furan aldehydes will undergo acid catalyzed aldol condensation with acetone in the medium. The complex product will consist of C5-C20 range compounds resulting from cross aldol condensation between biomass derived furans and acetone, as well as acetone self-condensation products. The biocrude produced by this catalytic process is stable and composed of well-defined stable furanic alkene and enone products, which are then upgraded to hydrocarbons using established catalytic reduction technology.