Constructing efficient PtCu active species via surface Si-OH-modulation for enhanced propane dehydrogenation

Surface hydroxyl modulation on S-1 enables the rational design of PtCu catalyst. • Surface OH modulates particle surface density and promotes PtCu interaction. • The optimal 0.5Pt2Cu/S-1–950 demonstrated an approving PDH activity. Propane dehydrogenation (PDH) is a promising approach for propylene production. However, Pt-based catalysts suffer from severe coke deposition and metal sintering at high temperature, thus leading to a rapid deactivation and low propylene yield. Herein, a surface hydroxyl (OH) strategy is developed to modulate the dispersion and configuration of PtCu active sites on silicalite-1 (S-1). The precise regulation of OH density effectively optimizes the particle density of PtCu species. The properly introduced surface OH provides suitable sites to anchor the PtCu active sites with an enhanced catalytic activity and stability. The optimal 0.5Pt2Cu/S-1–950 catalyst achieves an initial propane conversion of 63.4%, propylene space–time yield of 0.60 g g cat. -1 h −1 , and exceptional long-term stability. Moreover, the catalyst also exhibits low coke formation rate with a total coke content of only 1.5 wt% after 6 h of reaction, thereby avoiding the coverage of active sites. The surface Si-OH-modulation offers an effective strategy for constructing high-efficiency Pt-based catalysts with an improved durability for propane dehydrogenation. Download: Download high-res image (111KB) Download: Download full-size image