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Solid superacid catalyst is a newly developed catalytic materials, including SO 4 2 - / M x O y type the S 2 O 8 the 2 - / the M x O y -type solid superacid catalyst has high catalytic activity, selectivity, and preparation method is simple, and does not pollute the environment, non-corrosive, reusable outstanding advantages, especially in the petrochemical industry, the petroleum refining industry has broad application prospects, and thus become one of the focus in recent years, the field of catalysis. 2 - the SO 4 / ZrO 2 -type catalysts based on introduction of precious metals the Pd and adopt the WO 3 as the first two component preparation of Pd-SO 4 2 - / ZrO the 2 - WO 3 -type solid superacid catalyst using FT-IR, XPS, TG-DTA, XRD, ICP, TPR, SEM, BET, NH 3 -TPD characterization means the catalyst was characterized. N-pentane isomerizes probe reaction to study the W content of Pd content catalyst activation degree of isomerization performance. The results showed that: ZrO 2 crystallization temperature of the amount of W can be improved to inhibit SO 4 decomposition of 2 - , increase the ratio of surface area of ??the carrier , to increase the acid strength of the catalyst and the acid content; Pd enables significantly lower the reduction temperature of the catalyst, enhance the hydrogen spillover effect of carrier surface. When the WO 3 content (mass fraction, W), 13.0% the Pd mass fraction of 0.05%, the activation temperature of 300 ° C, the palladium-SO 4 2 - / ZrO the 2 -WO 3 solid superacid catalytic activity of the best. When the super acid catalyst at a reaction pressure of 2.0MPa, and the temperature was 260 ° C, airspeed for 1.0H-1, hydrogen to hydrocarbon ratio of 4.0, under the process conditions catalytic isomerization reaction of n-pentane, iso-pentane, yield in 80h can be stabilized at the above 35.0%, the selectivity is always more than 95.3%. S 2 O 8 2 - / ZrO 2 -type catalyst based study, through the introduction of precious metals Pd and the Al 2 O 3 prepared as the second component of the Pd-S 2 O 8 2 - / the ZrO 2 -Al 2 O 3 -type solid super acid catalyst and the preparation process of the solid superacid n-pentane isomerization. Experiment, n-pentane as raw materials, in 10mL continuous flow fixed-bed high-pressure microreactor - chromatography combined unit on catalyst evaluation. By means of FT-IR, XPS, TG-DTA, XRD, TPR, SEM, BET, NH 3 -TPD characterized investigated the Al 2 O content, Pd content, calcination temperature, and other preparation conditions on the Catalyst Performance, while initially explored the factors and regeneration of the catalyst deactivation. The results show that: the Al can be improved ZrO 2 the crystallization temperature, inhibit the decomposition of the sulfate to increase the ratio of surface area of ??the catalyst, to improve the reduction of the catalyst performance, to increase the acid strength of the catalyst and the acid content. When Al 2 O 3 mass fraction of 2.5%, the Pd mass fraction of 0.05%, the calcination temperature of 650 ° C, the activation temperature of 300 ℃, Pd-S2O82? / ZrO sub > 2 -Al 2 O 3 isomerization catalyst showed the highest activity. This catalyst at 230 ° C, 2.0MPa, hydrogen to hydrocarbon ratio is 4.0 and the WHSV 1.0h-1, under the process conditions catalytic n-pentane isomerization reaction of n-pentane conversion rates of up to 67.87%, the yield can be achieved 64.3%.
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