Complex Metal Halides and Mounted Superacids

Metal halides complexed with certain compounds exhibit superacidic character as evidenced by conversion of saturated hydrocarbons at room temperature or below. Among these materials are AICI3 complexed with other halides or sulfates, and SbFs mounted on metal oxides. 

Aluminum chloride, when combined with proper cocatalyst, shows high catalytic activity at low temperatures for acid catalyzed reactions such as alkanes cracking and skeletal isomerization. Hydrogen chloride is the most common cocatalyst. 

Some attempts have been made to prepare solid superacids by combining AlCb with solid cocatalysts. A complex of AICI3 with crosslinked polystyrene sulfonic acid was prepared and its catalystic activity examined in alkanes reactions. nie catalyst showed activity to catalyze cracking and isomerization of hexane at 353 K. 

A solid superacid is prepared from AICI3 and CuCh. A mixture of AICI3 and CuCh is kneaded under nitrogen atmosphere. The resulting material catalyzes pen- 

By combining AICI3 with different metal chlorides, solid superacids are also prepared. The catalytic activities of the superacids for pentane conversion are summarized in Table 3.43. The most active catalyst is obtained by a combination of AICI3 and TiCls 1/3 AICI3. 

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