Determination of conjugated diolefins in cracked naphtha

Proton Nuclear Magnetic Resonance (1H-NMR) Methodology for Monolefin Analysis: Application to Aquaprocessing-Upgraded Bitumen

“…Olefin determination for cracked petroleum products has been the subject of a published review . Conjugated diolefins, those described by others as the most deleterious components, , were often determined in light petroleum products by the Diels–Alder type reaction with maleic anhydride as described by the time consuming UOP-326 standard, modified by others in order to improve the final titration of unreacted maleic anhydride . SFC with ultraviolet detection (UV) at a specific conjugated diolefin wavelength (240 nm) has been discussed, and the six most common methodologies for conjugated diene analysis have been reviewed …”

“…19 Conjugated diolefins, those described by others as the most deleterious components, 3,4 were often determined in light petroleum products by the Diels−Alder type reaction with maleic anhydride as described by the time consuming UOP-326 standard, 20 modified by others in order to improve the final titration of unreacted maleic anhydride. 21 SFC with ultraviolet detection (UV) at a specific conjugated diolefin wavelength (240 nm) has been discussed, 22 and the six most common methodologies for conjugated diene analysis have been reviewed. 4 When analysis of olefins and/or diolefins pertains to the whole oil, bitumen, or their upgraded products, most of the previously described methods do not apply for two important reasons: (1) sample isomerism is so complex that no resolution is achievable and (2) most GC methods fail because of low analyte volatility, and SFC has solubility issues with the CO 2 eluent.…”