The Formation of Petroleum - Research Paper Example

Petroleum is a naturally occurring liquid which possesses great energy. Mainly, they are found below the earth’s surface in oil reservoirs correlatedwith sedimentary rocks.  It is inferred that petroleum is originated from animal and plant debris. Further, the energy possesses by petroleum is due to the energy in animal, and plants.  Combination of hydrocarbons with varying quantity of sulfur, nitrogen and oxygen is the major constituent of petroleum. Further, trace amount of organometallic compound is also detected. The proportion of the petroleum constituent varies considerably from one reservoir to another. Petroleum finds extreme application in today’s world; it is used as the principal source of energy. Petroleum powered nearly all conveyances, further it is used to generate electricity, and in making of paints, soaps, plastics, inks, and medicines, etc. Beyond any shadow of doubt todays world in incomplete without petroleum. However, petroleum cannot be used directly as a fuel or chemical producer because of its highly complex nature and presence of poisonous or corrosive impurities. Therefore, it is processed and refined to separate amalgams into simpler fractions that can be used as fuels, lubricants, or chemical producers. Tremendous growth and research is observed in the field of Petroleum due to its wide application, complex formation, structure, and refinement processing (“Petroleum”). Fomation of Petroleum Petroleum is originated from the debris of animal and plant i.e. perpetuated organic material, that’s why it is also known as a fossil fuel. Sea floor (oceanic anoxic events), Oxygen-minimum zones, and anoxic silled basins are the areas where organic material can stockpile ("Petroleum Formation").  It is widely recognized because of low oxygen level organic material gets preserved i.e. prevents degradation. Kerogen (Tucker 262) a waxy substance is formed by the burial diagenesis of organic material. It believes high temperatures (50-80 oC) is enough for developing the sedimented rocks and initiate the production of alkanes and cyclo-alkanes.  Subsequently, petroleum is formed by hydrocarbon pyrolysis on intense temperature and pressure. Oil window is the area, where the probability of petroleum production is highest, ordinally the temperature of the oil window is around 75-120 oC, and it located at a depth of 2-3.5 Km. Once the petroleum is generated, it is shifted to reservoir rocks from where it is collected. Unfortunately, the time required between the rock depositions to oil window, i.e. maturation period is not sorted out yet. However, generally it takes million of years. Among several factors behind petroleum generation, it believes that the significant quantity of oil may generate if burial time is huge even temperature is lower than required. For example, Paleozoic basins give rise to significant oil at 50 degrees Celsius while 115 oC are required for oil production via the younger Mio-Pliocene basins at nearly the identical burial depth. In addition to, it is observed that Paleozoic source rocks developed during the Cretaceous times, due to large tectonic activity occurring (Tissot, and Welte 699). Composition of Petroleum Hydrocarbon, non-hydrocarbon (S, O, N, etc.), organometallic compounds and inorganic salts are the constituent of petroleum ("Petroleum composition"). Hydrocarbon: Principal constituent of petroleum is the hydrocarbon; closely all types of hydrocarbon are present in petroleum. Alkenes and alkyne are the only two hydrocarbons which are not present in petroleum. Following is the major classes of hydrocarbons present in petroleum. 1. Alkanes It is saturated hydrocarbon and also recognized as paraffins.  Generally, alkanes are symbolized by a formula CnH2n+2. It is present in a dissolved state within the petroleum. 2. Cycloparaffins It is saturated hydrocarbon and also known as napthenes, present in crude oil. However, its ratio is dependent on the type of petroleum. The lower members of naphthenes are cyclopentane, cyclohexane, and their mono-substituted compounds. They are normally present in the light and the heavy naphtha fractions. Heavier petroleum fractions such as kerosene and gas oil may contain two or more cyclohexane rings fused through two vicinal carbons. 3. Aromatic compounds Mononuclear aromatic compound such as benzene, xylene is found in crude oil but in varied amounts.  They serve essential elements in the form of petrochemical intermediates and gasoline components. Unfortunately, distillation of BTX aromatics from petroleum is not practicable because of there low concentrations. However, catalytic amending process can be employed for enhancing a naphtha fraction with these aromatics. It is found that larger fractions than naphtha are present of binuclear aromatic hydrocarbons. Furthermore, tri-nuclear and polynuclear aromatic hydrocarbons build major part of crude oil in conjunction with heterocyclic compounds.  Other constituents Along hydrocarbons, some non-hydrocarbons compounds are also occurred in the petroleum. Non-hydrocarbon compound includes sulfur, nitrogen, and oxygen. These impurities cause several problems, including pollution, poisonous, corrosion, etc. Trace amount of inorganic salts (salt of calcium and magnesium with carboxylic acids) and organometallic compounds (such as sodium, calcium, magnesium, iron, etc.) is present in petroleum. However, they are present in trace amount but removal of inorganic salts and metal is necessary before processing because of their harmfulness, i.e. poisonous, corrosion, etc. Processing petroleum Various processing methodologies are subjected to extract the intermediates of petroleum. These include a primary distillation step to separate the crude oil complex mixture into simpler fractions. Primarily, these intermediate are used as fuels, but it also finds application as secondary raw materials for obtaining olefins, diolefins, and aromatics for the production of petrochemicals.  Besides these, chemical composition of petroleum intermediates can be varied to form new products for improved quality. For example, reforming a naphtha fraction catalytically produces a reformate rich in aromatics. The major use of the reformate is to increase the gasoline pool due to its high octane rating. However, the reformate is also used to take out the aromatics for petrochemicals use. At this point, the production of intermediates for petrochemicals is not separable from the production of fuels. The intermediates of petroleum are separated by several separation techniques. These include physical separation techniques (atmospheric distillation, vacuum distillation, absorption, adsorption process, and solvent extraction, etc.)  and chemical conversion processes (viscosity breaking, fluid coking, delayed coking, and catalytic conversion process, etc.) (Sami, and Lewis 11) Fractional distillation is performed for refining petroleum since it is the fundamental process thus discussed. In this process, crude oil is heated beyond 400 C in a fractionating column. By this process, numbers of petroleum products are obtained at different temperatures and being condensed. It is observed more than 500 compounds are formed when fractional distillation is performed up to 200 C.  While performing distillation, petrochemicals, natural gas is the first to form (below 20 oC). Petroleum ether is formed between 20-60 oC. Ligroin, and naphtha is obtained when the temperature reached 60 – 120 oC.  Gasoline, kerosene, jet oil, gas oil, diesel is formed in the range of 120 – 400 oC. Twently percent of petrol is yielded through fractional distillation.  Therefore, additional quantities of petrol are obtained by cracking of higher boiling fractions.  It involves splitting the larger molecules of the less volatile fractions into smaller molecules of greater volatility by subjecting them to high temperatures and pressures in the presence of catalyst. Cracking not only yield petrol but also ethene, propene, butene, etc., which find application in making of drugs, detergents, plastics, fertilizers and synthetic rubber, etc.  Furthermore, cracking yields some important chemicals like ethanol, phenol and acetone, etc. Product derivates of Petroleum Product derviatives of petroleum include wide range of products, few of them are 1. Liquefied petroleum gas: It is flammable amalgamate of hydrocarbon, chiefly used as power source in vehicle and warming gadgets. 2. Alkenes: It is unsaturated hydrocarbon and byproduct of petroleum. Generally, it is converted into plastics. 3. Lubricants: It is a supplement, used to aid in the reduction of friction between two parts. 4. Aromatic petrochemicals: It is used as precursors in chemical production. 5. Other derivatives of petroleum includes, sulfuric acid, bulk tar, asphalt, petroleum coke, jet fuels, gasoline, petrol, disel etc References 1. Tucker, M.E. Sedimentary petrology - an introduction to the origin of sedimentary rocks. 3rd ed. Blackwell Science Ltd, 2001. 26. 2. Tissot, B., and D.N. Welte. Petroleum Formation and Occurence. 2nd ed. Springer Verlag, 1984. 699. 3. Sami, M., and F.H. Lewis. Chemistry of Petrochemical processes. 2nd ed. Gulf Publishing Company, 2000. 11. 4. "Fossile Preservation." Petroleum Formation. Columbia, n.d. Web. 21 May 2011. . 5. Petroleum n. pag. Web. 22 May 2011. . 6. Petroleum composition n. pag. Web. 22 May 2011. . Read More