Hb Zhang

Forty years of applied catalysis research at Xiamen University and its interaction with fundamental catalysis research

Abstract This paper gives a concise, chronological review of 40 years of applied catalysis research done at Xiamen University, in acetylene and olefin conversion, nitrogen fixation, and in more detail CO hydrogenation to methanol and ethanol, oxidative coupling of methane, and oxidative dehydrogenation of light alkanes; some references of more recent work in other areas related to applied catalysis are also given.

Ag/La0.6Sr0.4MnO3/γ-Al2O3 catalysts for complete oxidation of methanol at low concentration

Ag-modified La 0.6 Sr 0.4 MnO 3 -based catalysts with the perovskite structure were prepared, and their activity for methanol complete oxidation was evaluated. The results showed that over a 6%Ag-modified 20% La 0.6 Sr 0.4 MnO 3 /γ-Al 2 o 3 catalyst, the T 50 and T 95 were as low as 395 and 413 K, respectively, and even at so low reaction temperature, the contents of the reaction intermediates HCHO and CO in the exit-gas were both under the detection limits. The origin of promoter action by Ag was discussed together with the results of spectroscopic characterization of the catalysts.

Dehydro-aromatization of CH4 over W-Mn(or Zn, Ga, Mo, Co)/HZSM-5(or MCM-22) catalysts*

Several promoted W/HZSM-5(or MCM-22)-based catalysts for DHAM reaction were developed.Over the W-Zn-Ga(or Mo-Co)/MCM-22 catalyst,70% selectivity of benzene (SBen) at 14∼17% conversion of methane (XCH4) could be achieved at 1073 K. XPS and NH3-TPD measurements demonstrated that heavy deposition of carbon was the main reason leading to deactivation of the catalyst. Reoxidation by air can regenerate the deactivated W-based catalyst effectively.

CHARACTERIZATION OF MOSX-K+/SIO2 CATALYSTS FOR SYNTHESIS OF MIXED ALCOHOLS FROM SYNGAS

Abstract Characteristic studies, by means of XRD, XPS, LRS, IR and TPD methods, of MoS x -K 4 /SiO 2 catalysts for mixed alcohols synthesis provide experimental evidence for formation of Mo-S-K surface phase and presence of disulfide species, (S-S) 2− , at the surface of the catalysts. One of the origins of the promoter action in shifting the selectivity from hydrocarbons to alcohols is likely that addition of the alkali salt led to a decrease in concentration of (S-S) 2− at the surface, which in turn would reduce the generation of the reactive hydrogen.