Diatomite Stabilized KOH: An Efficient Heterogeneous Catalyst for Cyclopentanone Self‐condensation

Abstract 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/SiO 2 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, Na 2 O, Al 2 O 3 ) 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.