Aldol condensation of cyclopentanone is an attractive reaction for bio‐jet fuel production. KOH is an efficient homogeneous catalyst for aldol condensation but suffering the problem of separation. In this paper, a heterogeneous catalyst, diatomite stabilized KOH (KOH/diatomite) was prepared in a simple way (dry‐mixed impregnation process), and exhibited good activity (overall yield: 85.0 %) and reusability. To clarify the support effect of diatomite, KOH/SiO₂ catalyst was also prepared. According to characterizations of these two catalysts, we suggest that the excellent catalytic activity of KOH/diatomite can be attributed to the formation of K−O−Si bond. In addition, the impurity elements existed in diatomite (e. g. CaO, Na₂O, Al₂O₃) and higher BET surface areas may also benefit to this reaction. This study provides a new possibility for converting homogeneous catalyst (KOH) to heterogeneous catalyst (KOH/diatomite). In this way, KOH/diatomite performed excellent catalytic activity and exhibited stable reusability, which can avoid the problem of separation and pollution.

中文翻译：

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硅藻土稳定的KOH：高效的环戊酮自缩合异构催化剂

环戊酮的醛醇缩合反应对于生物喷气燃料的生产是有吸引力的反应。KOH是用于醛醇缩合的有效的均相催化剂，但是存在分离的问题。本文以一种简单的方法（干混浸渍法）制备了一种非均相催化剂，硅藻土稳定的KOH（KOH /硅藻土），并具有良好的活性（总收率：85.0％）和可重复使用性。为了阐明硅藻土的载体效果，还制备了KOH / SiO ₂催化剂。根据这两种催化剂的表征，我们认为KOH /硅藻土的优异催化活性可归因于K-O-Si键的形成。另外，在硅藻土中存在杂质元素（例如CaO，Na ₂ O，Al ₂ O ₃）和较高的BET表面积也可能有益于该反应。这项研究为将均相催化剂（KOH）转化为非均相催化剂（KOH /硅藻土）提供了新的可能性。以此方式，KOH /硅藻土表现出优异的催化活性并且表现出稳定的可重复使用性，这可以避免分离和污染的问题。