We report on the aldol condensation of furfural and cyclopentanone in aqueous and biphasic mediums as a promising step for producing sustainable aviation fuel. Key parameters, including catalyst concentration, reactant concentration, temperature, and solvent, were found to significantly influence conversion and product selectivity. Alkaline conditions were essential for aldol coupling, with significant conversion observed at pH 12 and higher. The activation energies for the formation of the dimeric and trimeric aldol adducts were similar at 74 and 76 kJ/mol, respectively. Biphasic conditions were employed to prevent product precipitation, leading to reactor and equipment fouling. For biphasic conditions, the extraction of the reactants and dimeric intermediates to the organic phase affected rate and selectivity, resulting in the dilemma. Good product extraction leads to inevitable reactant extraction. Based on these findings, an integrated biphasic process design was proposed, utilizing process-owned solvents to optimize the separation and recycling of aqueous streams and improve the overall process efficiency.

中文翻译：

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糠醛和环戊酮的水相和双相偶联用于合成生物喷气燃料前驱体


我们报道了糠醛和环戊酮在水性和双相介质中的羟醛缩合，这是生产可持续航空燃料的一个有前途的步骤。研究发现，催化剂浓度、反应物浓度、温度和溶剂等关键参数对转化率和产物选择性有显著影响。碱性条件对于羟醛偶联至关重要，在 pH 值 12 或更高时观察到显著的转化率。形成二聚体和三聚体羟醛加合物的活化能相似，分别为 74 和 76 kJ/mol。采用双相条件来防止产品沉淀，从而导致反应器和设备结垢。对于双相条件，反应物和二聚体中间体对有机相的萃取影响速率和选择性，导致两难境地。良好的产物萃取会导致不可避免的反应物萃取。基于这些发现，提出了一种集成的双相工艺设计，利用工艺拥有的溶剂来优化水流的分离和回收，并提高整体工艺效率。