Abstract: The preparation of peroxodisulfated zirconia(PSZ) solid strong acid catalysts is introduced. It showed more active than sulfated zirconia (SZ) for n-butane isomerization at ambient temperature. Peroxodisulfate is the first type of nonhalide found to be more efficient than sulfate which so far has been found the best one promoted zirconia. The optimum calcination temperature is 600 ℃, which is 50 ℃ lower than that of SZ. The conversion of n-butane over PSZ was 50.4% during 20 h and at 35 ℃, and 36.7% over SZ under the same condition. According to X-Ray differential, TEM, BET and chemical analysis, it can be concluded that the formation of superacids over PSZ is similar to that over SZ. It is worth to point out the particle sizes of PSZ calcined between 500 ℃ and 800 ℃ are in the range of nanometers, and the optimum PSZ has both tetragonal and limited monoclinic zirconia.

Key words: S₂O₈^2-/ZrO₂, Solid superacid, n-Butane isomerization