Acetylene hydrochlorination over tin nitrogen based catalysts: effect of nitrogen carbondots as nitrogen precursor

Authors: YIBO WU, FUXIANG LI, QINGBIN LI, SONGTIAN LI, GANQING ZHAO, XUERONG SUN, PEISONG LIU, GUOXV HE, YONGJUN HAN, LIPING CHENG, SHIYING LUO

Abstract: The catalysts comprising the main active compounds of Sn-N_x were synthesized using trichlorophenylstannane ((C₆H₅)Cl₃Sn), nitrogen carbon-dots (NCDs), and activated carbon (AC) as starting materials, and the activity and stability of catalysts was evaluated in the acetylene hydrochlorination. According to the results on the physical and chemical properties of catalysts (TEM, XRD, BET, XPS and TG), it is concluded that NCDs@AC can increase (C₆H₅)Cl₃Sn dispersity, retard the coke deposition of (C₆H₅)Cl₃Sn/AC and lessen the loss of (C₄H₅)Cl₃Sn, thereby further promoting the stability of (C₆H₅)Cl₃Sn/AC. Based on the characterization results of C2H2- TPD and HCl adsorption experiments, we proposed that the existence of Sn-Nx can effectively strengthen the reactants adsorption of catalysts. By combing the FT-IR, C₂H₂-TPD and Rideal-Eley mechanism, the catalytic mechanism, in which C₂H₂ is firstly adsorbed on (C₆H₅)Cl₃Sn to form (C₆H₅)Cl₃Sn-C₂H₂ and then reacted with HCl to produce vinyl chloride, is proposed.

Keywords: Trichlorophenylstannane, nitrogen carbon-dots, vinyl chloride, acetylene hydrochlorination

Full Text: PDF