Process for the skeletal isomerisation of linear olefins with a pretreated molecular sieve and catalyst containing a pretreated sieve

摘要

A new process for the skeletal isomerisation of a charge contg. 4-20C linear olefin hydrocarbons, using a catalyst contg. a molecular sieve with a pore size of 0.4-0.8 nm is disclosed. This is pretreated by contacting with a 4-20C hydrocarbon, at a spatial velocity of 0.1-45 hr<-1> ,300-500 degrees C, and 0.1-1 MPa for 0.5-48 hrs., in order to deposit coke within the pores of the sieve. Also claimed is the prepared catalyst system. Pref. the catalyst is selected from the prods. ferrierite, the silico-alumino phosphates SAPO-31 and SAPO-11, &thetas; -1,EU-1, omega zeolite, mordenite, Nu-10, Nu-86 and Nu-87. This is contacted with a 4-20C hydrocarbon (esp. a 4-12C mono-olefin, mono-olefin, poly-olefin or alkane) at a VVH of 0.1-45 hr<-1>, 300-550 (esp. 400-535) degrees C., and 0.1-1 (esp. 0.1-0.5) MPa, in the absence of H2, for a period of 0.5-48 (esp. 0.5-24) hrs.. The hydrocarbon is diluted with an inert gas.