Diesel plastics-derived

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]. 

STORAGE STABILITY OF PLASTIC-DERIVED DIESEL FUEL... 

Diesel fuel made from the thermal cracking of plastics is more susceptible to oxidation and polymerization than refinery-made diesel fuels. This is because plastic-derived diesel fuels generally have terminal unsaturation (i.e. double bonds) at the ends of the diesel chains as a result of the P-scission chain cleavage. Over time free radicals that form in the plastic-derived diesel fuels during storage cause the diesel chains with double bonds (a-olefins) to polymerize resulting in a sludgy sediment also known as gum . 

The halogen-free plastic-derived oil obtained dnring the pilot plant studies was tested in diesel power generation engines in a 1 3 mixtnre with commercial fuel oils (kerosene) and the test was snccessfnl. 

The fuels that are derived from petroleum supply more than half of the world s total supply of energy. Gasoline, kerosene, and diesel oil provide fuel for automobiles, tractors, tmcks, aircraft, and ships. Fuel oil and natural gas are used to heat homes and commercial buildings, as well as to generate electricity. Petroleum products are the basic materials used for the manufacture of synthetic fibers for clothing and in plastics, paints, fertilizers, insecticides, soaps, and synthetic rubber. The uses of petroleum as a source of raw material in manufacturing are central to the functioning of modem industry. 

However, it is still qnestionable as to how far plastics pyrolysis can yield prodnct fractions, according to cnrrent specifications withont extensive post-pyrolysis purification. At Sapporo University, good olefin yields were obtained in the thermal cracking of oil, derived from the local plastics-to-oil plant. The Niigata oil is locally used in a diesel engine and not for sale ... 

Although direct liquefaction of waste plastic looked promising, problems associated with impurities (paper, aluminum, etc.) and chlorine derived from PVC caused operational difficulties. Consequently, it currently appears that the first step of any feedstock recycling process for waste plastics or tires should be pyrolysis, which allows much easier separation of solid impurities and chlorine. Research on pyrolysis of post-consumer plastic has been carried out by Kaminsky and co-workers [17, 18], Conrad Industries [19, 20], and Shah et al. [21]. Shah et al. [21] conducted pyrolysis experiments on relatively dirty post-consumer waste plastic obtained from the DSD. The pyrolysis oils were then subjected to hydroprocessing to convert them into high-quality transportation fuels (gasoline, kerosene, diesel). 

Oils and fats are also used for non-food purposes, such as the production of motor fuels, in oleochemistry and cosmetics. For these purposes, common edible oils and fats of lower quality are used. Some oils are obtained specifically for technological purposes, such as castor oil or tung oil. A typical example of the use of oils as fuel for diesel engines is the production of fatty acid methyl esters, especially from rapeseed oil. Oleochemicals from oils and fats manufacturing include fatty acids, fatty alcohols and other derivatives for the production of surfactants and subsequently detergents, paints, plastics, adhesives, building materials and many other products. 

Biodiesel can be used in its pure form (BlOO) or blended with petroleum diesel (a common blend is known as B20, a mixture of 80% petroleum diesel and 20% biodiesel). Biodiesel is not raw vegetable oil, but rather is a product derived from the oil. Biodiesel has a slightly lower fuel value than petroleum diesel, but has greater lubricity than current low sulfur diesel fuel. Biodiesel also has a higher flash point, and will gel at low temperatures of about -10 °C, making use in cold weather conditions difficult. Biodiesel is compatible with most parts in commercial diesel engine systems, and thus could almost be used as a drop-in replacement in trucks, buses, boats, and construction equipment. However, the difficulties associated with low-temperature operation and the potential degradation of plastic parts in the fuel system have made the B20 blend the typical fuel associated with biodiesel use. 

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