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采用程序升温催化反应技术、程序升温吸脱附技术、原位红外光谱技术研究了Pd、Pt组分及CO对Pd(Pt)/Al_2O_3催化剂氢氧反应活性的影响.结果表明,原料气中无CO存在时,单铂催化剂对氢氧反应的活性高于Pd-Pt双金属催化剂,有CO存在时,Pd-Pt催化剂反而优于单铂催化剂;CO使Pd-(Pt)/Al_2O_3催化剂活性降低的主原因是由于CO与H_2之间的竞争吸附,CO占据了H_2吸附的部分活性位,以及催化剂表面上被吸附的CO与O_2和被吸附的H_2与O_2之间的竞争反应所致;当氧含量低于化学计量时,CO歧化反应所导致的积炭在单铂催化剂表面上比在Pd-Pt催化剂上严重.
The effects of Pd, Pt components and CO on the reaction of hydrogen and oxygen of Pd (Pt) / Al 2 O 3 catalyst were studied by using temperature-programmed catalytic reaction, programmed temperature-programmed desorption and desorption and in situ FTIR spectroscopy. In the presence of CO, the activity of the single-platinum catalyst for hydrogen and oxygen reactions is higher than that of the Pd-Pt bimetallic catalyst, but Pd-Pt catalyst is better than the single-platinum catalyst in the presence of CO. CO reduces the activity of the Pd- (Pt) / Al 2 O 3 catalyst Is mainly due to the competitive adsorption between CO and H 2. CO occupies some active sites of H 2 adsorption and the competitive reaction between adsorbed CO and O 2 and adsorbed H 2 and O 2 on the catalyst surface. When When the oxygen content is less than the stoichiometric amount, the carbon deposition caused by the CO disproportionation reaction is severe on the surface of a single platinum catalyst than on a Pd-Pt catalyst.