Petroleum, Naphtha and Anti-Knock Agents

• Finely divided solids when suspended in a moving gas or liquid behave like a fluid.
• Catalysts in this form are used for catalytic cracking.
• Petroleum is a highly complex mixture of paraffinic, cycloparaffinic (naphthenic), and aromatic compounds.
• Petroleum contains traces of N, O, and a low percentage of S and is obtained from underground sources.
• Naphtha is a refined petroleum product.
• 90% of naphtha distills below 240°C, and 10% distills below 175°C.
• Naphtha is obtained by cracking petroleum and is mainly used as thinners for paints and varnishes.
• Flash point represents the lowest temperature.
• Flash point is the lowest temperature at which the vapor of a volatile liquid or solid gets ignited by a small flame, for example, the flash point of kerosene is 90°F.
• Anti-knock agents increase the octane number.
• Anti-knock agents are organometallic compounds that increase the octane number of gasoline when added in low percentage.
• TEL (tetraethyl lead) is a common anti-knock agent and can increase the octane number over 100%.
• Octane Number and Cetane Number details can be found on text page 396.
• Aviation gasoline is a variety of gasoline with a high octane number, generally around 100, and high volatility, used for aircraft.
• The main components of aviation gasoline are isoparaffins and some TEL.
• Straight run gasoline is gasoline obtained by direct distillation of petroleum without using other conversion processes like cracking.
• Straight run gasoline's octane number is low.
• LPG (Liquefied Petroleum Gas) is obtained from 'Wet Natural gas' from underground by washing it with gas oil and fractionating the useful fraction.
• LNG (Liquefied Natural Gas) is simply liquefied natural gas.
• Reforming details can be found on text page 395.
• The difference between gross and net calorific values can be found on text page 378.

Basic Reactions / Conversion Processes for Petrochemical Industry

• Petroleum offers a fertile field both for gasoline and for petrochemicals.
• Cracking: C7H15-C15H30-C7H15 heated becomes C7H16 + C6H12=CH2 + C14H28 = CH2, resulting in gasoline and antiknock gasoline.