PETROLEUM

PETROLEUM

Petroleum, from Latin petrus - rock and oleum - oil, also dubbed as the black gold, is a thick liquid, dark brown or greenish flammable, which is located in the upper layer of the few areas in the earth's crust. Petroleum is composed of a complex mixture of different hydrocarbons, the majority of the alkane series, but vary in appearance, composition, and purity. Petroleum is a mixture of different types of hydrocarbons.

Composition of Petroleum
Have a mixture of petroleum hydrocarbons as 50-98% by weight, the remainder consisting of organic substances containing sulfur, oxygen, and nitrogen, and inorganic compounds such as vanadium, nickel, sodium, iron, aluminum, calcium, and magnesium. In general, the composition of petroleum consists of carbon (C) 84-87%, Hydrogen (H) 11-14%, Sulfur (S) 0-3% Nitrogen (N) 0-1%, Oxygen (O) 0 - 2%.
Based on the content of compounds, petroleum hydrocarbons can be divided into groups and non-hydrocarbon and metal compounds.

1. Hydrocarbons
Group major hydrocarbons are paraffins, olefins, naften, and aromatic.
1.1. Paraffin
is a group of straight-chain saturated hydrocarbons (alkanes), CnH2n +2. Examples are methane (CH4), ethane (C2H6), n-butane (C4H10), isobutane (2-methyl propane, C4H10), isopentane (2-methylbutane, C5H12), and isooctane (2,2,4-trimethyl pentane, C8H18). The number of compounds belonging to the compound isoparaffins far more than the compounds belonging to n-paraffin. However, in the crude oil, isoparaffins compound levels are usually smaller than the n-paraffin.
1.2. Olefin
Olefin is a group of unsaturated hydrocarbons, CnH2n. For example, ethylene (C2H4), propene (C3H6), and butene (C4H8).
1.3. Naften
Naften are saturated hydrocarbons that form a ring structure with molecular formula CnH2n. These compounds are commonly found naften group is a compound ring structure composed of 5 or 6 carbon atoms. Examples are cyclopentane (C5H10), methylcyclopentane (C6H12) and cyclohexane (C6H12). Generally, in the crude petroleum, naftena a hydrocarbon group which has the second highest level after n-paraffin. CnH2n -6 has a ring of 6 (six).
only present in small amounts, but it is necessary in gasoline because:
- Has anti-knock high prices
- Good storage stability
- And other uses as fuels (fuels).
1.4. Aromatic
Aromatic hydrocarbons are unsaturated cored carbon atoms that form a benzene ring (C6H6). For example, benzene (C6H6), metilbenzen (C7H8), and naphthalene (C10H8). Oil from Sumatra and Kalimantan Aromat generally have relatively large levels.
In general, an alkane hydrocarbon most but sometimes (referred to as crude napthenic) containing cycloalkanes as the largest component, while the aromatic component is always the least.
Refinery / distillation (refining) is the process of changing crude oil into products that can be sold (marketeble product) through a combination of physical and chemical processes. Products resulting from the refining / refining, among others:
1. Light destilates is the component with the smallest molecular weight. Here are a few pieces:
• Gasoline

Gasoline (United States) or motor spirit (UK) or gasoline (Indonesia) has the lowest boiling point and is a key product in the distillation is used as a propellant motors (45% of the crude oil processed to produce gasoline).
• Naphta

Naphta is a material that has a boiling point between gasoline and kerosene. Some naphta used as: - Solvent rubber - starting materials ethylene - the military used as a jet fuel known as JP-4. - Solvent dry cleaning (washing)

• kerosine

Kerosene has the highest boiling point and is usually used as:
- Kerosene
- Fuel for water jet plane
Intermediate destilates a gas oil or diesel fuel use as a transportation fuel heavy trucks, trains, small commercial boats, farm equipment and others.
Heavy destilates is a high molecular weight component. This fraction is usually converted into lubricating oil (lubricant oils), oil with high specific gravity of the fuel, candles and cracking stock.
Residues including asphalt, residual fuel oil and petrolatum. Residues that do not have a large percentage.


2. Non Hydrocarbon
In addition to compounds composed of carbon atoms and hydrogen, found in petroleum are also non-hydrocarbon compounds such as sulfur, nitrogen, oxygen, vanadium, nickel and sodium bound hydrocarbon chain or ring. These elements are generally undesirable in products of petroleum refining, so its presence will greatly affect the processing steps performed on the oil.

2.1. Sulfur
Sulfur present in the form of hydrogen sulfide (H2S), sulfur-free (S), mercaptans (R-SH, with R = alkyl group), sulfides (RS-R '), disulfides (RSS-R') and tiofen (cyclic sulfide) . Sulfur compounds are not desirable because:
a. cause odor and corrosive nature of the product processing.
b. reduce the effectiveness of these substances in the product bubuhan processing.
c. poison cracking catalysts.
d. causes of air pollution (the burning of fossil fuels, the sulfur compound is oxidized to corrosive substances that harm the environment, namely SO2 and SO3).
2.2. Nitrogen
The compounds of nitrogen divided into substances that are like 3-metilpiridin bases (C6H7N) and quinoline (C9H7N) and substances that are not base such as pyrrole (C4H5N), indole (C8H7N) and carbazole (C12H9N). The compounds of nitrogen can disrupt the smooth catalytic processing if it gets carried over into the product, adversely affect the odor, color stability, and aging properties of the product.
2.3. Oxygen
Oxygen is usually tied to the carboxylate groups in naphthenic acids (2,2,6-trimetilsikloheksankarboksilat, C10H18O2) and fatty acids (alkanoic), phenolic hydroxyl group and ketone group. Oxygen compounds does not cause serious problems such as sulfur compounds and nitrogen compounds in catalytic processes.

3. Metal compounds
Oil typically contains 0.001 to 0.05% by weight of metal. Metal content is usually highest vanadium, nickel and sodium. These metals are dissolved in a salt water suspended in oil or in the form organometal compound soluble in oil. Vanadium and nickel are toxic catalysts for petroleum processing and can cause problems if carried over into prduk processing.