Diesel unsaturated hydrocarbons

The dominantly unsaturated nature of the upper smear zone was also distinct in that it had a substantially lower percentage (10%) of total volatile (gasoline-range) vs. total recoverable (diesel-range) hydrocarbons. In contrast, the lower smear zone contained 25% total volatile hydrocarbons. The difference was thought to be due to the dominantly saturated nature of the lower smear zone, which limited the amount of volatilization that could occur. However, the dramatic difference in TPH concentration was thought to be largely attributable to intrinsic bioremediation. 

Similar to petroleum-derived cracking the fractions from plastics pyrolysis can contain a significant concentration of unsaturated hydrocarbons (especially a-olefins) [9]. The mono- and diolefin content makes the diesel fuel prone to instability due to polymerization and the formation of deposits (i.e. gums). Since the plastic-derived diesel fuel has an appreciable olefins content it is important to subject it to a hydrogenation step (e.g. hydrogenation over PCI/AI2O3 at 300-320°C and 3 MPa H2) which lowers the bromine number from typical values of 22-28 g Br2/100 g to less than 0.5 g Br2/100 g [9]. 

Fuel oil 2 is characterized by hydrocarbon chain lengths in the Cn-C20 range, whereas diesel fuels predominantly contain a mixture of C10-C19 hydrocarbons (ATSDR 1995g). The composition consists of approximately 64% aliphatic hydrocarbons (straight chain alkanes and cycloalkanes), 1-2% unsaturated hydrocarbons (alkenes), and 35% aromatic hydrocarbons (including alkylbenzenes and 2-, 3-ring aromatics) (Air Force 1989). Fuel oil 2 contains less than 5% polycyclic aromatic hydrocarbons (IARC 1989b). The typical hydrocarbon composition of fuel oil 2 is presented in Table E-4.b (Appendix E). 

Snare M, Kubickovd I, Maki-Arvela P, Chichova D, Eranen K, Murzin DY. Catalytic deoxygenation of unsaturated renewable feedstocks for production of diesel fuel hydrocarbons. Fuel 2008 87 933. 

Much knowledge on the effect of poisons has been generated in connection to reformer-based PEMFC systems. Both for transport as well as for stationary applications, the presence of CO, CO2, NH3 has to be taken into account besides N2 and H2O [100]. For reformer-based systems that are operated dynamically, that is, including many cold starts and load variations, CO concentrations exceed the 10 ppm level frequently [104]. The effect of CO is studied most extensively. For unalloyed platinum electrodes, CO concentrations as low as 10 ppm lead to a performance loss of 100 mV [105] at 70°C. When reformer-based systems are fueled with logistic fuels, such as diesel and kerosene, other contaminants than CO and CO2 are present in the reformate. Especially aromatics and unsaturated hydrocarbons can poison the fuel cell anode fast and irreversibly, even in concentrations so low that they are hardly detectable with state-of-the-art analytics. 

Uses are the manufacture of - furan ( tetrahy-drofuran), - furfuryl alcohol, ->methylfuran and nitrofurans, which are intermediates for making antimicrobial reagents. It is also used as a selective solvent in the separation of saturated and unsaturated compounds in lubricating oils, gas oil and diesel fuels, as well as in extractive distillation of CVCs hydrocarbons for manufacturing S3mthetic rubbers. Other uses are as reactive solvent in corrosion-resistant - furfuryl alcohol resins and in high-carbon phenol resins (abrasive wheels and brake linings). Furfuryl acrylate is used as monomer in vinyl-polymerization. 

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