III International Conference

PP-II-65and 99.995 % mass.) were saturated with solutions of H 2 PtCl 6 or PdCl 2 in order to obtain0.5 % mas. of metal in the sample composition. The catalysts samples were dried at 393 Kand were reduced with hydrogen (mixture 10 % H 2 in Ar) during 1 h at 673 K. For the jointintroduction of Pt(Pd) and Cs + catalysts were saturated with solution of CsJO 3 accounting on0.05 % mass. Cs + in the catalyst. These samples were dried at 393 K and reduced in a streamof hydrogen-argon mixture (10 % H 2 ) during 1 h at 673 K. To compare the catalysts withstandards, Pt(Pd)/γ-Al 2 O 3 with 0.5 % mass. of metals were prepared. Treatment withhydrogen of these catalysts was conducted for the standards just as for Pt(Pd)/MoO 3 andPt(Pd)/WO 3 . Composition, specific surface (S) and temperature of achieving certain degree ofthe conversion (T 20% , T 40% , T 100% ), are listed in a table.Table. Temperatures of certain conversion degree of H 2 , CO and CH 4 (%) in K on thecatalysts of oxidation.SampleT 20% T 40% T 80% T 10% T 30% T 100% T 10% T 20% T 35%H 2 oxidation CO oxidation CH 4 oxidation0.5%Pt/Al 2 O 3 298 307 330 460 478 486 755 768 8000.5%Pd/Al 2 O 3 310 318 336 448 470 478 750 770 785WO 3 475 556 - 660 768 - - - -MoO 3 526 610 - 715 805 - - - -0.05%Cs + /WO 3 408 450 550 628 685 - - - -0.05%Cs + /MoO 3 486 550 - 625 738 - - - -0.5%Pt/WO 3 273 286 302 362 410 432 615 640 6980.5%Pd/WO 3 273 293 310 383 425 442 623 642 6700.5%Pt/MoO 3 273 286 302 390 450 463 630 658 693*0.5%Pd/MoO 3 273 292 310 400 442 455 634 645 680*0.5%Pt⋅0.05%Cs + /WO 3 273* 283 294 350 400 4200.5%Pd⋅0.05%Cs + /WO 3 - 273 288 360 418 4300.5%Pt⋅0.05%Cs + /MoO 3 273 280 290 390 442 4480.5%Pd⋅0.05%Cs + /MoO 3 273* 283 297 388 435 442* Note: temperature was determined for 30% conversion.In the reactions of gas-phase oxidization for reaction mixtures (1% Н 2 (CO, CH 4 ) and20 % O 2 in inert gas (Ar, He)) it is observed that introduction of Pt(Pd) in TO 3 (T = Mo, W)results in increasing of S in 5-6 times, addition of Cs + to these catalytic systems results in thefurther S increase. The trioxides posses low activity in oxidization of H 2 and CO, but inmethane complete oxidation they are quite inactive. Hence after reduction with H 2 , thecatalytic activity of systems containing Pt(Pd) in these reactions increases considerably ascompared to Pt(Pd)/γ-Al 2 O 3 . For the reaction of CO oxidation considerable extent oftemperature region of low-active state of catalyst with X