Olefin/Paraffm Separation

Besides the well-established applications there are a number of emerging membrane gas separations. These are, for example, natural gas hydrocarbon dewpointing, olefin/paraffm separation and separation of hydrocarbon isomeres. These will be addressed in the following material section. The purpose of this chapter is to provide an overview of state-of-the-art and emerging materials for gas-separation membranes, to give some key features of integral asymmetric and composite membranes and finally to explain the influence of basic process parameters. 

Similar copolyimide was prepared using 3,7-diamino-2,8(6)-dimethyldibenzothiopheneS,5-dioxide (DDBT) instead of m-SED and its performance for olefin/paraffm separation was investigated [74]. Block copolymers of liquid crystalline polyamide and amorphous PI were prepared from a two-pot polycondensation reaetions [75]. Hydrocarbon (C-2 and C-3) separations in copolyimide dense membranes derived from 6FDA, DDA and 1,5-naphthalene diamine (NDA) was studied [76]. Gas transport properties of 6FDA, DDA and 3, 3 -diaminodiphenyl sulfone (DIDS) was reported [77]. 

This process, applied to the treatment of C4 cuts and more specifically to the manufacture of 1-butene, is one the many variants of adsorption technology on molecular sieves called Sorbex and developed by UOF, to separate paraffms (Molex). olefins (Olex)... 

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