Natural sources of hydrocarbons chemistry briefly. Abstract: Natural sources of hydrocarbons. Environmental impact

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Lesson objectives:

• Educational:
• Develop students' cognitive activity.
• To familiarize students with natural sources of hydrocarbons: oil, natural gas, coal, their composition and processing methods.
• To study the main deposits of these resources globally and in Russia.
• Show their significance in the national economy.

Consider environmental protection issues.

• Educational:

Cultivating interest in studying the topic, instilling speech culture in chemistry lessons.

• Educational:

Develop attention, observation, listening skills and drawing conclusions.

• Pedagogical methods and techniques:
• Perceptual approach.
• Gnostic approach.

Cybernetic approach. Equipment:

Interactive whiteboard, multimedia, electronic textbooks of MarSTU, Internet, collections “Oil and the main products of its processing”, “Coal and the most important products of its processing”.

During the classes

I. Organizational moment.

I introduce the purpose and objectives of this lesson.

II. Main part.

The most important natural sources of hydrocarbons are: oil, coal, natural and associated petroleum gases. Oil – “black gold”

(I introduce students to the origin of oil, main reserves, production, composition of oil, physical properties, and refined products).

During the rectification process, oil is divided into the following fractions: I am showing samples of fractions from the collection

• (demonstration accompanied by explanation). Distillation gases
• – a mixture of low-molecular hydrocarbons, mainly propane and butane, with a boiling temperature of up to 40 ° C, Gasoline fraction (gasoline) – HC composition C 5 H 12 to C 11 H 24 (boiling point 40-200°C, with a finer separation of this fraction one gets gas oil (petroleum ether, 40 - 70°C) and petrol
• (70 - 120°C), Naphtha fraction
• – HC composition from C 8 H 18 to C 14 H 30 (boil temperature 150 - 250°C), Kerosene fraction
• – HC composition from C 12 H 26 to C 18 H 38 (boil temperature 180 - 300°C), Diesel fuel

– HC composition from C 13 H 28 to C 19 H 36 (boil temperature 200 - 350°C) Residue from oil refining – fuel oil – contains hydrocarbons with the number of carbon atoms from 18 to 50. Distillation under reduced pressure from fuel oil produces solar oil (C 18 H 28 – C 25 H 52), lubricating oils (C 28 H 58 – C 38 H 78), petrolatum And paraffin – low-melting mixtures of solid hydrocarbons. Solid residue from fuel oil distillation - and products of its processing - bitumen petrolatum asphalt used for making road surfaces.

The products obtained as a result of oil rectification are subjected to chemical processing. One of them is cracking.

Cracking is the thermal decomposition of petroleum products, which leads to the formation of hydrocarbons with a smaller number of carbon atoms in the molecule. (I use the MarSTU electronic textbook, which talks about the types of cracking).

Students compare thermal and catalytic cracking. (Slide No. 16)

Thermal cracking.

The breakdown of hydrocarbon molecules occurs at a higher temperature (470-5500 C). The process proceeds slowly, hydrocarbons with an unbranched chain of carbon atoms are formed. Gasoline obtained as a result of thermal cracking, along with saturated hydrocarbons, contains a lot unsaturated hydrocarbons. Therefore, this gasoline has greater detonation resistance than straight distilled gasoline. Thermally cracked gasoline contains many unsaturated hydrocarbons, which easily oxidize and polymerize. Therefore, this gasoline is less stable during storage. When it burns, various parts of the engine can become clogged.

Catalytic cracking.

The splitting of hydrocarbon molecules occurs in the presence of catalysts and at a lower temperature (450-5000 C). The main focus is on gasoline. They are trying to get more of it and definitely best quality. Catalytic cracking appeared precisely as a result of long-term, stubborn struggle oil workers for improving the quality of gasoline. Compared to thermal cracking, the process proceeds much faster, and not only the splitting of hydrocarbon molecules occurs, but also their isomerization, i.e. hydrocarbons with a branched chain of carbon atoms are formed. Catalytically cracked gasoline is even more resistant to detonation than thermally cracked gasoline.

Coal. (I introduce students to the origins coal, main reserves, production, physical properties, processed products).

Origin: (I use the electronic textbook of MarSTU, where they talk about the origin of coal).

Main reserves: (slide number 18) On the map I show students the largest coal deposits in Russia in terms of production volume - these are the Tunguska, Kuznetsk, and Pechora basins.

Production:(I use the MarSTU electronic textbook, where they talk about coal mining).

• Coke gas– which includes H 2, CH 4, CO, CO 2, impurities of NH 3, N 2 and other gases,
• Coal tar– contains several hundred different organic substances, including benzene and its homologues, phenol and aromatic alcohols, naphthalene and various heterocyclic compounds,
• Nadsmolnaya, or ammonia water– contains dissolved ammonia, as well as phenol, hydrogen sulfide and other substances,
• Coke– solid coking residue, almost pure carbon.

Natural and petroleum associated gases. (I introduce students to the main reserves, production, composition, processed products).

III. Generalization.

In the summary part of the lesson, I created a test using the Turning Point program. The students armed themselves with remote controls. When a question appears on the screen, by pressing the appropriate button, they select the correct answer.

1. The main components of natural gas are:

• Ethane;
• Propane;
• Methane;
• Butane.

2. Which fraction of petroleum distillation contains from 4 to 9 carbon atoms per molecule?

• Naphtha;
• Gas oil;
• Petrol;
• Kerosene.

3. What is the purpose of cracking heavy petroleum products?

• Methane production;
• Obtaining gasoline fractions with high detonation resistance;
• Synthesis gas production;
• Hydrogen production.

4. Which process is not related to oil refining?

• Coking;
• Fractional distillation;
• Catalytic cracking;
• Thermal cracking.

5. Which of the following events is the most dangerous for aquatic ecosystems?

• Violation of oil pipeline tightness;
• Oil spill as a result of a tanker accident;
• Violation of technology during deep oil production on land;
• Transportation of coal by sea.

6. From methane, which forms natural gas, we obtain:

• Synthesis gas;
• Ethylene;
• Acetylene;
• Butadiene.

7. What features distinguish catalytic cracking gasoline from straight distilled gasoline?

• Presence of alkenes;
• Presence of alkynes;
• The presence of hydrocarbons with a branched chain of carbon atoms;
• High detonation resistance.

The test result is immediately visible on the screen.

Homework:§ 10, ex.1 – 8

Literature:

1. L.Yu. Alikberova “Entertaining chemistry”. – M.: “AST-Press”, 1999.
2. O.S. Gabrielyan, I.G. Ostroumov “Handbook for chemistry teachers, grade 10.” – M.: “Blik and K,” 2001.
3. O.S. Gabrielyan, F.N. Maskaev, S.Yu. Ponomarev, V.I. Terenin “Chemistry 10th grade.” – M.: “Drofa”, 2003.

Origin of fossil fuels.

In addition to the fact that all living organisms are composed of organic substances, the main sources of organic compounds are: oil, coal, natural and associated petroleum gases.

Oil, coal and natural gas are sources of hydrocarbons.

These natural resources are used:

· As a fuel (source of energy and heat) – this is conventional combustion;

· In the form of raw materials for further processing – this is organic synthesis.

Theories of the origin of organic substances:

1- Theory organic origin.

According to this theory, the deposits were formed from the remains of extinct plant and animal organisms, which turned into a mixture of hydrocarbons in the thickness of the earth's crust under the influence of bacteria, high pressure and temperature.

2- Theory of mineral (volcanic) origin of oil.

According to this theory, oil, coal and natural gas were formed during the primary stage of the formation of planet Earth. In this case, the metals combined with carbon to form carbides. As a result of the reaction of carbides with water vapor in the depths of the planet, gaseous hydrocarbons were formed, in particular methane and acetylene. And under the influence of heat, radiation and catalysts, other compounds contained in oil were formed from them. In the upper layers of the lithosphere, liquid oil components evaporated, the liquid thickened, turned into asphalt and then into coal.

This theory was first expressed by D.I. Mendeleev, and then in the 20th century, the French scientist P. Sabatier simulated the described process in the laboratory and obtained a mixture of hydrocarbons similar to oil.

Main component natural gas is methane. It also contains ethane, propane, butane. The higher the molecular weight of the hydrocarbon, the less of it is contained in natural gas.

Application: When natural gas burns, it releases a lot of heat, so it serves as an energy-efficient and cheap fuel in industry. Natural gas It is also a source of raw materials for the chemical industry: the production of acetylene, ethylene, hydrogen, soot, various plastics, acetic acid, dyes, medicines and other products.

Associated petroleum gases are found in nature above oil or dissolved in it under pressure. Previously, associated petroleum gases were not used; they were burned. Currently, they are captured and used as fuel and valuable chemical raw materials. Associated gases contain less methane than natural gas, but they contain significantly more of its homologues. Associated petroleum gases are separated to a narrower composition.

For example: gas gasoline - a mixture of pentane, hexane and other hydrocarbons is added to gasoline to improve engine starting; propane-butane fraction in the form of liquefied gas is used as fuel; dry gas - similar in composition to natural gas - is used to produce acetylene, hydrogen, and also as fuel. Sometimes associated petroleum gases are subjected to more thorough separation and individual hydrocarbons are extracted from them, from which unsaturated hydrocarbons are then obtained.

One of the most common types of fuel and raw material for organic synthesis remains coal. What types of coal are there, where does coal come from and what products is it used to produce - these are the main questions that we will consider in today’s lesson. As a source chemical substances Coal began to be used earlier than oil and natural gas.

Coal is not an individual substance. Its composition includes: free carbon (up to 10%), organic substances containing, in addition to carbon and hydrogen, oxygen, sulfur, nitrogen, minerals that remain in the form of slag when burning coal.

Coal is a solid combustible mineral of organic origin. According to the biogenic hypothesis, it was formed from dead plants as a result of the vital activity of microorganisms in the Carboniferous period Paleozoic era(about 300 million years ago). Coal is cheaper than oil, it is more evenly distributed in earth's crust, its natural reserves far exceed oil reserves and, according to scientists, will not be exhausted for another century.

The formation of coal from plant residues (coalification) occurs in several stages: peat – brown coal – hard coal – anthracite.

The process of carbonification consists of a gradual increase in the relative content of carbon in organic matter as a result of its depletion in oxygen and hydrogen. Peat formation and brown coal occurs as a result of biochemical decomposition of plant residues without access to oxygen. The transition of brown coal to stone occurs under the influence of elevated temperatures and pressures associated with mountain-forming and volcanic processes.

Remember: distillation (distillation) is a method of separating a mixture of volatile liquids by gradual evaporation followed by condensation.

Oil. Oil distillation

Many of the organic substances you deal with in Everyday life,—plastics, paints, detergents, medicines, varnishes, solvents—are synthesized from hydrocarbons. There are three main sources of hydrocarbons in nature - oil, natural gas and coal.

Oil is one of the most important mineral resources. It is impossible to imagine our life without oil and its products. It’s not for nothing that oil-rich countries play important role in the global economy.

Oil is a dark, oily liquid found in the earth's crust (Fig. 29.1). It is a homogeneous mixture of several hundred substances - mainly saturated hydrocarbons with the number of carbon atoms in the molecule from 1 to 40.

To process this mixture, both physical and chemical methods are used. First, oil is separated into simple mixtures - fractions - by distillation (distillation or rectification), based on the fact that various substances in the oil boil at different temperatures(Table 12). Distillation occurs in a distillation column under significant heating (Fig. 29.2). Factions with the most high temperatures boilings that decompose at high temperatures are distilled under reduced pressure.

Table 12. Oil distillation fractions

Ukraine is quite rich in oil reserves. The main fields are concentrated in three oil and gas regions: eastern (Sumy, Poltava, Chernihiv and Kharkov regions), western (Lviv and Ivano-Frankivsk regions) and southern (Black Sea region, shelves of the Azov and Black Seas). Oil reserves in Ukraine are estimated at about 2 billion tons, but a significant part of them is concentrated at great depths (5-7 km). Annual oil production in Ukraine is about 2 million tons with a demand of 16 million tons, so, unfortunately, Ukraine is still forced to import significant volumes of oil.

Chemical refining of petroleum products

Some petroleum distillation products can be used immediately, without further processing, such as gasoline and kerosene, but they make up only 20-30% of oil. In addition, after distillation, gasoline is of low quality (with a low octane number, i.e., when compressed in the engine, it explodes rather than burns). An engine running on such fuel makes a characteristic knocking noise and quickly fails. To improve the quality of gasoline and increase its yield, oil is subjected to chemical processing.

One of the most important methods of chemical oil refining is cracking (from the English to crack - to split, break, since during cracking the carbon chains are broken) (Fig. 29.3). When heated to 500 °C without air access in the presence of special catalysts, long alkane molecules are split into smaller ones. When cracking saturated hydrocarbons, a mixture of light saturated and unsaturated hydrocarbons is formed, for example:

Thanks to this process, the yield of gasoline and kerosene increases. This type of gasoline is sometimes called cracked gasoline.

One of the characteristics that determines the quality of gasoline is the octane number, which indicates the possibility of detonation (explosion) of the fuel-air mixture in the engine. The higher the octane number, the lower the likelihood of detonation, and therefore the higher the quality of gasoline. Heptane is unsuitable as a motor fuel; it is more likely to detonate, while isooctane (2,2,4-trimethylpentane) has the opposite properties - it almost does not detonate in the engine. These two substances became the basis for the scale for determining the quality of gasoline - the octane number scale. On this scale, heptane received a value of 0, and isooctane - 100. According to this scale, gasoline with an octane rating of 95 has the same knocking properties as a mixture of 95% isooctane and 5% heptane.

Oil refining occurs at special enterprises - oil refineries. There they carry out both rectification of crude oil and chemical processing of the resulting petroleum products. There are six oil refineries in Ukraine: in Odessa, Kremenchug, Kherson, Lisichansk, Nadvornyansk and Drohobych. The total capacity of all Ukrainian oil refining enterprises exceeds 52 million tons per year.

Natural gas

The second most important source of hydrocarbons is natural gas, the main component of which is methane (93-99%). Natural gas is used primarily as an efficient fuel. When it burns, neither ash nor poisonous substances are formed. carbon monoxide, therefore natural gas is considered an environmentally friendly fuel.

A large number of natural gas is used by the chemical industry. Processing of natural gas is reduced mainly to the production of unsaturated hydrocarbons and synthesis gas. Ethylene and acetylene are formed by the elimination of hydrogen from lower alkanes:

Synthesis gas - a mixture of carbon(II) oxide and hydrogen - is produced by heating methane with water steam:

From this mixture, using different catalysts, oxygen-containing compounds are synthesized - methyl alcohol, acetic acid, etc.

When passed over a cobalt catalyst, the synthesis gas is converted into a mixture of alkanes, which is synthetic gasoline:

Coal

Another source of hydrocarbons is coal. In the chemical industry it is processed by coking - heating to 1000 ° C without air access (Fig. 29.5, p. 170). In this case, coke and coal tar are formed, the mass of which is only a few percent of the mass of coal. Coke is used as a reducing agent in metallurgy (for example, to obtain iron from its oxides).

Coal tar contains several hundred organic compounds, mainly aromatic hydrocarbons which are obtained from it by distillation.

Coal is also used as a fuel, but this creates large ecological problems. Firstly, coal contains non-flammable impurities, which turn into slag during fuel combustion; secondly, coal contains small amounts of Sulfur and Nitrogen compounds, the combustion of which produces oxides that pollute the atmosphere. Ukraine ranks one of the first in the world in terms of coal reserves. On an area equal to 0.4% of the world's territory, Ukraine contains about 5% of the world's reserves of energy raw materials, 95% of which is coal (about 54 billion tons). In 2015, coal production amounted to 40 million tons, which is almost half as much as in 2011. Today there are 300 coal mines in Ukraine, and 40% of them produce coking coal (which can be processed into coke). Production is concentrated mainly in the Donetsk, Lugansk, Dnepropetrovsk and Volyn regions.

Linguistic task

In Greek, pyro means "fire" and lysis means "decomposition." Why do you think the terms “cracking” and “pyrolysis” are often used interchangeably?

Key idea

The main sources of hydrocarbons for industry are oil, coal and natural gas. For more effective use, these natural resources must be processed to isolate individual substances or mixtures.

Control questions

334. Name the main natural sources of hydrocarbons.

335. What is the physical method of separating oil into fractions based on?

336. What fractions is oil divided into during distillation? Describe their use. Which petroleum product is the most valuable for modern society?

337. How do the most important petroleum products differ by chemical composition?

338. Using information from this and previous paragraphs, describe the use of natural gas in the chemical industry.

339. What are the main products produced by coking coal?

340. Why is coal heated during processing without air access?

341. Why is natural gas better than coal as a fuel?

342. What substances and materials are produced by processing coal and natural gas?

Assignments for mastering the material

343. In the process of cracking the hydrocarbon C 20 H 42, two products are formed with the same number of Carbon atoms in the molecules. Write an equation for the reaction.

344. What is the fundamental difference between oil cracking and rectification?

345. Why do you think that during direct distillation of oil it is not possible to process more than 20% of it into gasoline?

346. Analyze fig. 29.2 and describe how petroleum distillation occurs.

347. Write down equations for the reactions of producing ethylene and acetylene from natural gas components.

348. One of the components of gasoline is the hydrocarbon C 8 H 18. Write an equation for the reaction of its production from carbon(I) oxide and hydrogen.

349. When gasoline burns completely, carbon dioxide and water are formed in the engine. Write an equation for the combustion reaction of gasoline, assuming that it consists of hydrocarbons of the composition C 8 H 18.

350. Car exhaust gases contain toxic substances: carbon(N) oxide and nitrogen(N) oxide. Explain why chemical reactions they were formed.

351. How many times will the volume of the fuel-air mixture, consisting of 40 ml of octane vapor and 3 liters of air, increase when ignited? When making calculations, assume that the air contains 20% oxygen (by volume).

352. Gasoline sold in warm climates consists of hydrocarbons with a higher molecular weight than gasoline sold in cold climates. Guess why oil refiners do this.

353*. Oil contains so many valuable organic substances that D.I. Mendeleev said: “Burning oil in a furnace is almost the same as burning with banknotes.” How do you understand this statement? Suggest ways rational use natural sources of hydrocarbons.

354*. In additional sources, find information about materials and substances whose raw materials are oil, natural gas or coal. Can they be made without using natural sources of hydrocarbons? Is it possible for humanity to stop using these materials? Justify your answer.

355*. Using the knowledge gained in geography lessons in grades 8 and 9, describe the current and promising basins and areas of coal, oil, and natural gas production in Ukraine. Are the locations of processing plants for these hydrocarbon sources coordinated with their deposits?

This is textbook material

The most important sources of hydrocarbons are natural and associated petroleum gases, oil, and coal.

By reserves natural gas The first place in the world belongs to our country. Natural gas contains hydrocarbons with low molecular weight. It has the following approximate composition (by volume): 80–98% methane, 2–3% of its closest homologues - ethane, propane, butane and a small amount of impurities - hydrogen sulfide H 2 S, nitrogen N 2, noble gases, carbon monoxide (IV ) CO 2 and water vapor H 2 O . The composition of gas is specific to each field. There is the following pattern: the higher the relative molecular weight of the hydrocarbon, the less it is contained in natural gas.

Natural gas is widely used as a cheap fuel with a high calorific value (up to 54,400 kJ is released when 1 m 3 is burned). This is one of the best types of fuel for domestic and industrial needs. In addition, natural gas serves as a valuable raw material for the chemical industry: the production of acetylene, ethylene, hydrogen, soot, various plastics, acetic acid, dyes, medicines and other products.

Associated petroleum gases are in deposits together with oil: they are dissolved in it and are located above the oil, forming a gas “cap”. When extracting oil to the surface, gases due to sharp fall pressures are separated from it. Previously, associated gases were not used and were flared during oil production. Currently, they are captured and used as fuel and valuable chemical raw materials. Associated gases contain less methane than natural gas, but more ethane, propane, butane and higher hydrocarbons. In addition, they contain basically the same impurities as in natural gas: H 2 S, N 2, noble gases, H 2 O vapors, CO 2 . Individual hydrocarbons (ethane, propane, butane, etc.) are extracted from associated gases; their processing makes it possible to obtain unsaturated hydrocarbons by dehydrogenation - propylene, butylene, butadiene, from which rubbers and plastics are then synthesized. A mixture of propane and butane (liquefied gas) is used as household fuel. Gas gasoline (a mixture of pentane and hexane) is used as an additive to gasoline for better ignition of the fuel when starting the engine. The oxidation of hydrocarbons produces organic acids, alcohols and other products.

Oil– an oily, flammable liquid of dark brown or almost black color with a characteristic odor. It is lighter than water (= 0.73–0.97 g/cm3) and is practically insoluble in water. In terms of composition, oil is a complex mixture of hydrocarbons of different molecular weights, so it does not have a specific boiling point.

Oil consists mainly of liquid hydrocarbons (solid and gaseous hydrocarbons are dissolved in them). Typically these are alkanes (mostly of normal structure), cycloalkanes and arenes, the ratio of which in oils from different fields varies widely. Ural oil contains more arenes. In addition to hydrocarbons, oil contains oxygen, sulfur and nitrogenous organic compounds.

Crude oil is not usually used. To obtain technically valuable products from oil, it is subjected to processing.

Primary processing oil consists of its distillation. Distillation is carried out at oil refineries after separation of associated gases. When distilling oil, light petroleum products are obtained:

gasoline ( t boil = 40–200 °C) contains hydrocarbons C 5 – C 11,

naphtha ( t boil = 150–250 °C) contains hydrocarbons C 8 – C 14,

kerosene ( t boil = 180–300 °C) contains hydrocarbons C 12 – C 18,

gas oil ( t kip > 275 °C),

and the remainder is a viscous black liquid - fuel oil.

The fuel oil is subjected to further processing. It is distilled under reduced pressure (to prevent decomposition) and lubricating oils are isolated: spindle, machine, cylinder, etc. Vaseline and paraffin are isolated from fuel oil of some types of oil. The remainder of the fuel oil after distillation - tar - after partial oxidation is used to produce asphalt. The main disadvantage of oil distillation is the low yield of gasoline (no more than 20%).

Petroleum distillation products have various uses.

Petrol It is used in large quantities as aviation and automobile fuel. It usually consists of hydrocarbons containing an average of 5 to 9 C atoms in their molecules. Naphtha It is used as fuel for tractors, and also as a solvent in the paint and varnish industry. Large quantities it is processed into gasoline. Kerosene It is used as fuel for tractors, jet aircraft and rockets, as well as for domestic needs. Solar oil – – HC composition C 5 H 12 to C 11 H 24 (boiling point 40-200°C, with a finer separation of this fraction one gets– used as motor fuel, and (C 18 H 28 – C 25 H 52),– for lubrication of mechanisms. Petrolatum used in medicine. It consists of a mixture of liquid and solid hydrocarbons. Paraffin used for the production of higher carboxylic acids, for impregnating wood in the production of matches and pencils, for making candles, shoe polish, etc. It consists of a mixture of solid hydrocarbons. Fuel oil In addition to processing into lubricating oils and gasoline, it is used as boiler liquid fuel.

At secondary processing methods oil, the structure of the hydrocarbons included in its composition changes. Among these methods great importance has cracking of petroleum hydrocarbons, carried out to increase the yield of gasoline (up to 65–70%).

Cracking– the process of splitting hydrocarbons contained in oil, which results in the formation of hydrocarbons with a smaller number of C atoms in the molecule. There are two main types of cracking: thermal and catalytic.

Thermal cracking is carried out by heating the feedstock (fuel oil, etc.) at a temperature of 470–550 °C and a pressure of 2–6 MPa. At the same time, hydrocarbon molecules with a large number C atoms are split into molecules with a smaller number of atoms of both saturated and unsaturated hydrocarbons. For example:

(radical mechanism),

This method is used to produce mainly motor gasoline. Its yield from oil reaches 70%. Thermal cracking was discovered by Russian engineer V.G. Shukhov in 1891.

Catalytic cracking carried out in the presence of catalysts (usually aluminosilicates) at 450–500 °C and atmospheric pressure. This method produces aviation gasoline with a yield of up to 80%. This type of cracking mainly affects kerosene and gas oil fractions of oil. During catalytic cracking, along with splitting reactions, isomerization reactions occur. As a result of the latter, saturated hydrocarbons with a branched carbon skeleton of molecules are formed, which improves the quality of gasoline:

Catalytic cracking gasoline has a higher quality. The process of obtaining it proceeds much faster, with less thermal energy consumption. In addition, catalytic cracking produces relatively many branched-chain hydrocarbons (isocompounds), which are of great value for organic synthesis.

At t= 700 °C and above pyrolysis occurs.

Pyrolysis– decomposition of organic substances without air access at high temperatures. In the pyrolysis of oil, the main reaction products are unsaturated gaseous hydrocarbons (ethylene, acetylene) and aromatic hydrocarbons - benzene, toluene, etc. Since oil pyrolysis is one of the most important ways to obtain aromatic hydrocarbons, this process is often called oil aromatization.

Aromatization– transformation of alkanes and cycloalkanes into arenes. When heavy fractions of petroleum products are heated in the presence of a catalyst (Pt or Mo), hydrocarbons containing 6–8 C atoms per molecule are converted into aromatic hydrocarbons. These processes occur during reforming (gasoline upgrading).

Reforming- This is the aromatization of gasoline, carried out as a result of heating them in the presence of a catalyst, for example Pt. Under these conditions, alkanes and cycloalkanes are converted into aromatic hydrocarbons, as a result of which the octane number of gasoline also increases significantly. Aromatization is used to obtain individual aromatic hydrocarbons (benzene, toluene) from gasoline fractions of oil.

IN last years Petroleum hydrocarbons are widely used as a source of chemical raw materials. Different ways from them we obtain substances necessary for the production of plastics, synthetic textile fibers, synthetic rubber, alcohols, acids, synthetic detergents, explosives, pesticides, synthetic fats, etc.

Coal Just like natural gas and oil, it is a source of energy and valuable chemical raw materials.

The main method of processing coal is coking(dry distillation). When coking (heating to 1000 °C - 1200 °C without air access), various products are obtained: coke, coal tar, tar water and coke oven gas (diagram).

Scheme

Coke is used as a reducing agent in the production of cast iron in metallurgical plants.

Coal tar serves as a source of aromatic hydrocarbons. It is subjected to rectification distillation and benzene, toluene, xylene, naphthalene, as well as phenols, nitrogen-containing compounds, etc. are obtained. Pitch is a thick black mass remaining after distillation of the resin, used for the preparation of electrodes and roofing felt.

Ammonia, ammonium sulfate, phenol, etc. are obtained from tar water.

Coke oven gas is used to heat coke ovens (about 18,000 kJ are released when 1 m 3 is burned), but it is mainly subjected to chemical processing. Thus, hydrogen is isolated from it for the synthesis of ammonia, which is then used to produce nitrogen fertilizers, as well as methane, benzene, toluene, ammonium sulfate, and ethylene.

Disputes about the shape of the Earth do not diminish the importance of its contents. The most important resource has always been groundwater. They provide a priority need human body. However, without fossil fuels, which are the main supplier of energy for human civilization, human life seems completely different.

Fuel is a source of energy

Among all the fossils hidden in the depths of the Earth, fuel belongs to the combustible (or sedimentary) type.

The base is hydrocarbon, so one of the effects of the combustion reaction is the release of energy, which can easily be used to improve the comfort of human life. Over the past decade, about 90% of all energy used on Earth has been produced using fossil fuels. This fact gives us a lot to think about, given that the riches of the planet’s interior are non-renewable energy sources and are depleted over time.

Fuel types

Oil shale

Oil

Aerosols

Suspensions

Stone, anthracite, graphite

Sapropel

Shale gas

Tar sands

Emulsions

Ore gas

Liquid rocket fuel

Marsh gas

Manufactured using the Fischer-Tropsch process

Methane hydrate

Compressed gas

Solid fuel gasification products

The suppliers of all fossil fuels are oil, coal and natural gas.

Brief use as fuel

The raw materials for the production of energy resources are oil, coal, oil shale, natural gas, gas hydrates, and peat.

Oil- a liquid related to combustible (sedimentary) fossils. Consists of hydrocarbons and other chemical elements. The color of the liquid, depending on the composition, varies between light brown, dark brown and black. Compositions of yellow-green and colorless color are rarely found. The presence of nitrogen, sulfur and oxygen-containing elements in oil determines its color and smell.

Coal- name of Latin origin. Carbō is the international name for carbon. The composition contains bitumen masses and plant remains. It is an organic compound that has undergone slow decomposition under the influence of external factors(geological and biological).

Oil shale, like coal, are a representative of the group of solid combustible fossils, or caustobiolites (which is literally translated from Greek language sounds like “flammable life stone”). During dry distillation (under the influence high temperatures) forms resins similar in their chemical composition to oil. The composition of shales is dominated by mineral substances (calcide, dolomite, quartz, pyrite, etc.), but there are also organic substances (kerogen), which are found only in rocks High Quality reach 50% of the total composition.

Natural gas- a gaseous substance formed during the decomposition of organic substances. In the bowels of the Earth there are three types of accumulation of mixtures of gases: individual accumulations, gas caps of oil fields and as part of oil or water. At optimal climatic conditions the substance is only in the gaseous state. It may be found in the bowels of the earth in the form of crystals (natural gas hydrates).

Gas hydrates- crystalline formations formed from water and gas under certain conditions. They belong to the group of compounds of variable composition.

Peat- loose rock used as fuel, thermal insulation material, fertilizer. It is a gas-bearing mineral and is used as fuel in many regions.

Origin

Everything, that modern man extracts from the bowels of the earth and is a non-renewable natural resource. It took millions of years and special geological conditions for their appearance. Large amounts of fossil fuels were formed in the Mesozoic.

Oil- according to the biogenic theory of its origin, formation lasted for hundreds of millions of years from organic substances of sedimentary rocks.

Coal- is formed when decaying plant material is replenished faster than its decomposition occurs. Swamps are a suitable place for such a process. Standing water protects the layer of plant mass from complete destruction by bacteria due to its low oxygen content. Coal is divided into humic (comes from the remains of wood, leaves, stems) and sapropelite (formed mainly from algae).

The raw material for the formation of coal can be called peat. If it is immersed under layers of sediment, water and gases are lost under compression and coal is formed.

Oil shale- the organic component is formed using biochemical transformations of the simplest algae. It is divided into two types: thalloalginite (contains algae with intact cellular structure) and colloalginite (algae with loss of cellular structure).

Natural gas- according to the same theory of the biogenic origin of fossils, natural gas is formed at higher pressure and temperature readings than oil, which is proven by the deeper occurrence of deposits. They are formed from the same natural material(remains of living organisms).

Gas hydrates- these are formations whose appearance requires special thermobaric conditions. Therefore, they are formed mainly on sea bottom sediments and frozen rocks. They can also form on the walls of pipes during gas production, and therefore the fossil is heated to a temperature above hydrate formation.

Peat- formed in swamp conditions from incompletely decomposed organic plant remains. Deposited on the soil surface.

Production

Coal and natural gas differ not only in the way they rise to the surface. Gas deposits are located deeper than others - from one to several kilometers deep. The substance is located in the pores of reservoirs (a layer containing natural gas). The force that forces the substance to rise upward is the pressure difference in the underground formations and the collection system. Extraction occurs using wells, which they try to distribute evenly throughout the entire field. Fuel extraction thus avoids gas flows between sites and untimely watering of deposits.

Oil and gas production technologies have some similarities. Types of oil production are distinguished by methods of raising the substance to the surface:

• fountain (a technology similar to gas, based on the difference in pressure underground and in the liquid delivery system);
• gas lift;
• using an electric centrifugal pump;
• with installation of an electric screw pump;
• rod pumps (sometimes connected to a ground pump).

The extraction method depends on the depth of the substance. There are a huge number of options for bringing oil to the surface.

The method of developing a coal deposit also depends on the characteristics of the occurrence of coal in the ground. Open-pit mining is carried out when the fossil is found at a level of one hundred meters from the surface. A mixed type of mining is often carried out: first open method, then underground (using faces). Coal deposits are rich in other resources of consumer importance: these are valuable metals, methane, rare metals, and groundwater.

Shale deposits are developed either by mining (considered to be ineffective) or by in situ mining, which involves heating the rock underground. Due to the complexity of the technology, production is carried out in very limited quantities.

Peat is extracted by draining swamps. Due to the appearance of oxygen, aerobic microorganisms are activated, decomposing its organic matter, which leads to the release carbon dioxide with great speed. Peat is the cheapest type of fuel; its extraction is carried out constantly in compliance with certain rules.

Recoverable reserves

One of the assessments of society's well-being is based on fuel consumption per capita: the higher the consumption, the more comfortable people live. This fact (and not only) forces humanity to increase the volume of fuel production, affecting pricing. The price of oil today is determined by such an economic term as “netback”. This term implies a price that includes the weighted average cost of petroleum products (produced from the purchased substance) and delivery of raw materials to the enterprise.

Trading exchanges sell oil at CIF prices, which literally translates to “cost, insurance and freight.” From this we can conclude that the price of oil today based on transaction quotes includes the price of raw materials and transportation costs for its delivery.

Consumption rate

Taking into account the increasing rates of consumption natural resources It is difficult to give an unambiguous assessment of fuel availability for a long period. Given the current dynamics, oil production in 2018 will amount to 3 billion tons, which will lead to the depletion of world reserves by 80% by 2030. The supply of black gold is projected to be within 55 - 50 years. Natural gas could be exhausted within 60 years at current consumption rates.

There are much more coal reserves on Earth than oil and gas. However, over the last decade its production has increased, and if the pace does not slow down, then out of the planned 420 years (existing forecasts) the reserves will be depleted in 200.

Environmental impact

Increased use of fossil fuels leads to increased emissions of carbon dioxide (CO2) into the atmosphere, harmful influence on the climate of the planet which has been confirmed by international environmental organizations. If CO2 emissions are not reduced, an environmental catastrophe is inevitable, the beginning of which can be observed by contemporaries. According to preliminary estimates, from 60% to 80% of all fossil fuel reserves must remain untouched to stabilize the situation on Earth. However, this is not the only one by-effect use of fossil fuels. The extraction, transportation, and processing at refineries themselves contribute to environmental pollution with much more toxic substances. An example is the accident in the Gulf of Mexico, which led to the suspension of the Gulf Stream.

Limitations and Alternatives

Mining fossil fuels is a profitable business for companies whose main limitation is the depletion of natural reserves. People usually forget to mention that the voids created by human activity in the bowels of the earth contribute to the disappearance of fresh water on the surface and its penetration into deeper layers. The disappearance of drinking water on Earth cannot be justified by any benefits of fossil fuel extraction. And it will happen if humanity does not rationalize its stay on the planet.

Five years ago, motorcycles and cars with new generation engines (fuel-free) appeared in China. But they were released in strictly limited quantities (for a certain circle of people), and the technology became classified. This only speaks of the short-sightedness of human greed, because if you can “make money” from oil and gas, no one will stop the oil magnates from doing it.

Conclusion

Along with well-known alternative (renewable) energy sources, there are less expensive, but classified technologies. Nevertheless, their use must inevitably enter into a person’s life, otherwise the future will not be as long and cloudless as “businessmen” imagine it to be.