Phthalimide Ligand Coordination as a Critical “Key” for Constructing Chlorine–Platinum–Nitrogen Single-Site Catalysts for Effective Acetylene Hydrochlorination

Abstract

Owing to the low dispersion and deficiency of active species in Pt catalysts, Pt-complexes catalysts (Pt–L x /SAC–IPA) were synthesized using 2-propanol (IPA) solvent via ligand coordination strategy. The IPA, which exhibits a low boiling point and weak polarity, promotes the dispersion of Pt species. Further, the introduction of phthalimide ligand (L1) modulates the electronic properties of active metals, thereby constructing the single-site-dispersed Cl–Pt–N local structure bearing Pt­(II) (presumably the active center of the reaction). Concurrently, the enhanced adsorption and activation performances of the catalyst toward an HCl reactant, as well as its weakened performances toward a C2H2 reactant, improve its anticoking performance and lower the reaction energy barrier. Therefore, the most active Pt–L1/SAC–IPA catalyst achieves an outstanding performance comparable with that of the standard Au/activated carbon (AC)–aqua regia (AR) catalyst, and it is reasonable to conclude that the L1 ligand functioned as a critical “key” in the Pt-based catalytic acetylene hydrochlorination.

Progress in mercury-free catalysts for acetylene hydrochlorination

“…Zhang et al constructed a localized structure comprising a dispersed unit point of Cl-Pt-N, utilizing phthalimide (L1) as the ligand, which enhanced the adsorption and activation of the reactant HCl, improved the catalyst's coking resistance and reduced the reaction energy barrier. 62 This indicates that L1 ligand plays a pivotal role in the acetylene hydrochlorination reaction.…”

Advances in Single-Atom-Catalyzed Acetylene Hydrochlorination

“…Excitingly, introducing nitrogen-containing ligands can significantly enhance the catalytic performance and stability of platinum-based catalysts. Zhang et al 71 fabricated a more resilient Pt-L 1 /SAC-IPA catalyst by incorporating the phthalimide(L 1 ) ligand and utilizing 2propanol as the impregnation solvent. As depicted in Figure 6c, under identical reaction conditions (T = 473 K, total GHSV = 387 h −1 , and C 2 H 2 /HCl = 1:1.15), the Pt-L 1 /SAC-IPA catalyst demonstrated superior catalytic efficiency and remarkable stability.…”

“…(d,e) Pt 4 f XPS spectra of fresh and used Pt catalysts. Adapted with permission from ref . Copyright 2023 American Chemical Society.…”

Deep eutectic solvent boosted ruthenium catalysts for acetylene hydrochlorination

“…1 In recent years, numerous researchers have endeavoured to develop highly efficient and alternative catalysts to address this issue. These include precious metal catalysts such as Au, [2][3][4][5][6] Ru, [7][8][9][10] Pt, [11][12][13] and Pd, [14][15][16][17] as well as non-precious metal catalysts like Cu, [18][19][20][21][22] Sn, [23][24][25] and so on. While precious metal catalysts exhibit high activity, limited resources and exorbitant costs hinder their industrial application.…”