Petroleum or crude oil is a naturally occurring, toxic, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights, and other organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling. It is refined and separated, most easily by boiling point, into a large number of consumer products, from gasoline and kerosene to asphalt and chemicals used to make plastics and pharmaceuticals.
Fluid catalytic cracking (FCC) is the most important conversion process used in petroleum refineries. It is widely used to convert the high-boiling hydrocarbon fractions of...
HydrodesulfurizationLast Updated on 2013-12-15 23:43:02Hydrodesulfurization (HDS) or Hydrotreating is a catalytic chemical process widely used to remove sulfur compounds from refined petroleum products such as gasoline or petrol, jet fuel, diesel fuel, and fuel oils. One purpose for removing the sulfur is to reduce the sulfur dioxide emissions resulting from using those fuels in automotive vehicles, aircraft, railroad locomotives, ships, or oil burning power plants, residential and industrial furnaces, and other forms of fuel combustion.
Another important reason for removing sulfur from the intermediate product naphtha streams within a petroleum refinery is that sulfur, even in extremely low concentrations, poisons the noble metal catalysts platinum and rhenium in the catalytic reforming units that are subsequently used to upgrade the of the naphtha streams.
Hydrogenation of the sulfur compounds results in the formation of undesirable,... More »
Danish StraitsLast Updated on 2013-05-28 00:00:00
The Danish Straits are the three sea channels between Denmark and Sweden connecting the Baltic Sea to the North Sea through the Kattegat and Skagerrak. The three chief sea passages are:
Storebælt (Great Belt); and,
Lillebælt (Little Belt).
Oresund is the eastern-most of the Danish Straits, separating the Danish island of Zealand (Sjaelland in Danish) from the Swedish mainland.
Denmark and Sweden were linked in prehistoric times—until 7000 years ago when rising sea levels accompanying the end of the Ice Age severed the dry-land connection between the two.
At its narrowest, between Helsingor'/Elsinor (Demark) and Helsingborg (Sweden), the Oresund is approximately 2.5 miles (4 kilometres). A ferry connects the two sides, but the construction of a tunnel is... More »
Strait of MalaccaLast Updated on 2013-05-16 00:00:00
The Strait of Malacca, located between Indonesia, Malaysia, and Singapore, links the Indian Ocean to the South China Sea and Persian Gulf. The length of the strait is about 800 kilometres. At its narrowest point in the Phillips Channel of the Singapore Strait, Malacca is only approximately 1.7 miles wide, creating a natural bottleneck, as well as potential for collisions, piracy, grounding, or water pollution, particularly for oil spills.
The International Hydrographic Organization defines the limits of the Strait of Malacca as shown by the dashed lines on the map below. However, for practical purposes, many include the Singapore Strait as part of Malacca.
Base map source: Demis
Importance for Oil Transportation
Malacca is the shortest sea route between Persian Gulf suppliers and the Asian markets—notably China, Japan, South Korea, and the... More »
Vapor pressureLast Updated on 2012-04-24 00:00:00
Vapor pressure (also referred to as the equilibrium vapor pressure), is the pressure of a vapor in equilibrium with its liquid or solid phase. At any given temperature of a specific substance, there is a pressure at which the vapor phase of that specific substance is in thermodynamic equilibrium with its liquid or solid phases — i.e., when the rates at which molecules escape from and return into the vaporizing liquid or solid are equal. This is the vapor pressure of the specific substance at that temperature.
The vapor pressure of a substance increases with increasing temperature.
Volatility of liquids
The vapor pressure is an indication of a liquid's evaporation rate. It relates to the tendency of molecules and atoms to escape from a liquid or a solid. Any substance with a significant vapor pressure at temperatures of about 20 to 25 °C (68 to 77... More »
International Union of Pure and Applied ChemistryLast Updated on 2012-04-08 00:00:00
The International Union of Pure and Applied Chemistry (IUPAC) is a non-governmental scientific organization serving to advance all aspects of the chemical sciences and to contribute to the international application of chemistry by scientists, engineers and others. It is an association of organizations, called "National Adhering Organizations", which represent the chemists of different member countries. As of July 2009, there were 54 "National Adhering Organizations" plus some other countries that are linked to IUPAC as "Associate National Adhering Organizations".
The U. S. National Academy of Sciences is the U.S. National Committee for the International Union of Pure and Applied Chemistry (i.e., the IUPAC's National Adhering Organization for the United States.
The international headquarters office of the IUPAC is located in Zurich,... More »
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