Oligomerization and alkylation

A relatively sharp transition between oligomerization and alkylation activity has been measured with sulfuric acid at Hq values between — 8.0 and — 8.5 (109). If such low-acidity values occur in an alkylation reactor, oligomerization reactions become so predominant that the acid strength cannot be maintained and the plant is said to be in an acid runaway condition. 

Low temperature (100-250°C) conversion of olefins, notably oligomerization and alkylation, is made possible by involving cracking reactions to clean up the pore system [4] or to operate at very low olefin concentrations to prevent formation of deposits [5], respectively. Processing of olefins in the temperature range of say 300-500°C at high partial pressures of olefins is even more difficult. Skeletal isomerization of olefins and aromatisation of olefins are examples of desired reactions in this temperature range. 

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