Isolation and Identification of Paraffinic Hydrocarbons from Light Kerosene Obtained from Kuwait Oil

Abstract

Initial experiments in which ZnSe was sealed in Pyrex tubes with dry gaseous HC1 gave small quantities (<10% yield) of HvSe, H2, and Se after being heated as high as 773 K for 16 h. The rate was slow but catalysts might be found to speed the reaction which could also be driven under pressurized HC1 to shift the equilibrium. An experiment was also tried using HBr instead of HC1 with essentially identical results. ConclusionsConditions have been found under which ZnO, Se, and S02 react to produce ZnSe and ZnS04-The reaction proceeds rapidly to equilibrium at 773 K without detectable side reactions.Hydrolysis of ZnSe to give H2Se was found to go rapidly and quantitatively with dilute HC1 and slowly with dilute H2SC>4. Experiments also indicate concentrated HC1 will rapidly and completely hydrolyze ZnSe at ambient temperature using minimal quantities of water and HC1, and presently provides

Separation and Characterization of Paraffins and Naphthenes from FCC Feedstocks

“…For effecting complex formation, the presence of a polar compound (activator) such as water, aliphatic alcohol, or ketone expedites the complex formation (Weedman and Haddleston, 1955;Hess, 1954). Thiourea has been shown to form similar adducts with branched paraffins (Ijam and Al-Zaid, 1977) under a similar procedure. Molecular sieves (synthetic zeolites) can also be used for paraffin separation.…”

“…The available literature is limited, and this separation was applied only in some standard mixtures or in some light petroleum fraction (Altgelt and Gouw, 1979;Marsh and Smith, 1984;Nwadinique and Nwobobo, 1994). The two common approaches for isolating n-paraffins from other hydrocarbons are urea adduction (Ijam and Al-Zaid, 1977;Marquart et al, 1968;Nwadinique and Sunday, 1990) and adsorption in molecular sieves (Fitzerald et al, 1970;Mortimer and Luke, 1967;Washall et al, 1970). Urea crystallizes from solutions in a matrix where the n-paraffins, but not the branched or cyclic compounds, are included within urea's cylindrical pores.…”

“…For this process, various reaction temperatures have been used in the literature. Thus, some investigators use room temperature (Ijam and Al-Zaid, 1977;Nwadinique and Nwobobo, 1994) but others use higher temperatures (55-60 °C) in order to adduct heavier paraffins (Altgelt and Gouw, 1979). For the recovery of the lighter paraffins (C 11 -C 13 ), lower temperatures must be used (Marquart et al, 1968).…”