Alkanes. Aliphatic hydrocarbons - what are they? Limit hydrocarbons c12 c19 maximum permissible concentration
4.4.1 Impact of the facility on atmospheric air and characteristics of sources of pollutant emissions during operation
The main sources of pollutants are:
Reservoir Park
a) Liquid motor fuel
Draining into the tanks is carried out by gravity when the tanker engine is turned on. The release of pollutants occurs during fuel storage and drainage. The following pollutants are released: pentylenes (amylenes are a mixture of isomers), benzene, xylene, a mixture of saturated hydrocarbons C1-C5 and C6-C10, toluene, ethylbenzene, hydrogen sulfide, saturated hydrocarbons C12-C19. When the tanks are filled, fuel is not released to the fuel dispenser. Only one tank is filled at a time. Organized source of emissions - using a breathing valve of the tank;
The release of pollutants occurs during fuel storage and injection. The following pollutants are released: a mixture of saturated hydrocarbons C1-C5, methyl mercaptan. When the tanks are filled, fuel is not released to the fuel dispenser. Only one tank is filled at a time. An organized source of emissions is the reservoir's discharge plug.
Fuel - dispensers
a) Liquid motor fuel
Release of pollutants when pouring fuel into car tanks. The following pollutants are released: pentylenes (amylenes - a mixture of isomers), benzene, xylene, a mixture of saturated hydrocarbons C1-C5, C6-C10 and C12-C19, toluene, ethylbenzene, hydrogen sulfide. The source of unorganized emissions is the car tank;
b) Gaseous motor fuel (LPG)
The release of pollutants occurs when fuel is pumped into car cylinders (disconnecting the clamp, releasing it from the hose). The following pollutants are released: a mixture of saturated hydrocarbons C1-C5, methyl mercaptans (odorant). The source of unorganized emissions is the car cylinder.
LMC tank truck platform
Delivery of petroleum products to gas stations is carried out by fuel trucks, once every two days. The release of pollutants occurs as a result of the combustion of diesel fuel during operation of the tanker engine. The following pollutants are released: nitrogen oxide (III), nitrogen dioxide, sulfur dioxide (sulfur dioxide), kerosene, black carbon (soot), carbon monoxide. Area emission of pollutants.
Gas fuel tank truck site
Delivery of LPG to gas stations is carried out by tanker truck, once every two days. The release of pollutants occurs as a result of the combustion of diesel fuel during operation of the tanker engine (nitrogen is pumped through a sealed system). The following pollutants are released: nitrogen oxide (III), nitrogen dioxide, sulfur dioxide (sulfur dioxide), kerosene, black carbon (soot), carbon monoxide. Area emission of pollutants.
Parking for cars and trucks
The release of pollutants occurs during the operation of a car engine. The following are released into the atmosphere: gasoline, nitrogen dioxide, kerosene, carbon monoxide, sulfur dioxide, soot.
Storm water collection tank
A mixture of limiting C1-C5 hydrocarbons contained in wastewater is released into the atmosphere. The source of release is organized - the breathing valve of the tank.
The values of the maximum permissible concentration (MPC) in the atmospheric air of populated areas and the hazard class of harmful substances during operation are presented in Table 7.
Table 7 – Concentrations and hazard class of harmful substances
|
Substance |
Criterion used |
Criterion value, mg/m3 |
Hazard Class |
Total substance release |
|
Nitrogen dioxide | ||||
|
Nitric oxide | ||||
|
Sulfur dioxide | ||||
|
Hydrogen sulfide | ||||
|
Carbon monoxide | ||||
|
Pentylenes (amylenes, mixture of isomers) | ||||
Continuation of table 7
|
Methylbenzene | ||||
|
Ethylbenzene | ||||
|
Menthathiol | ||||
|
Gasoline (low sulfur petroleum) | ||||
|
Alkanes C12-C19, saturated hydrocarbons C12-C19 | ||||
|
Mixture of saturated hydrocarbons C1-C5 | ||||
|
Mixture of saturated hydrocarbons C6-C10 | ||||
|
Total substances | ||||
|
including solid | ||||
|
liquid/gaseous |
Based on the data given in Table 6, the following conclusions can be drawn. Background indicators of atmospheric air pollution do not interfere with the operation of gas stations. During operation, 2.5128671 tons/year of pollutants of 18 types from 2 to 4 hazard classes are expected to be released into the atmosphere .
page 1
page 2
page 3
page 4
page 5
page 6
page 7
page 8
page 9
page 10
page 11
page 12
page 13
page 14
page 15
page 16
page 17
FEDERAL ENVIRONMENTAL SERVICE,
TECHNOLOGICAL AND NUCLEAR SUPERVISION
RESEARCH INSTITUTE
AIR PROTECTION
(Research Institute Atmosphere)
PUBLIC CORPORATION
SARATOV OIL REFINERY
MEASUREMENT PROCEDURE
MASS CONCENTRATION OF THE AMOUNT OF SOLID HYDROCARBONS
C 12 - C 19 IN THE ATMOSPHERIC AIR OF THE SANITARY PROTECTION ZONE,
WORK AREA AIR AND INDUSTRIAL EMISSIONS
GAS CHROMATOGRAPHIC METHOD
PND F 13.1:2:3.59-07
MVI is certified by the Federal State Unitary Enterprise “VNIIM im. DI. Mendeleev"
Certificate No. 242/150-2005 dated November 14, 2005
Saint Petersburg
This document establishes a methodology for measuring (MVI) the mass concentration of the sum of saturated hydrocarbons C 12 - C 19 using a universal disposable sampler in the atmospheric air of the sanitary protection zone, the air of the working area and industrial emissions from production associated with the production, storage and transportation of petroleum products.
The range of measurements of the mass concentration of the sum of hydrocarbons C 12 - C 19 is from 0.80 to 10.0 - 10 3 mg/m 3.
The main characteristics of hydrocarbons C 12 - C 19 are given in Table 1.
Table 1
|
substance |
molar mass, g/mol |
T kip, °C |
|||
|
tridecane |
|||||
|
tetradecane |
|||||
|
pentadecane |
|||||
|
hexadecane |
|||||
|
heptadecane |
|||||
|
octadecane |
|||||
|
nonadecane |
1 Characteristics of measurement error
Expanded measurement uncertainty (with coverage factor k = 2):
U= 0.25 × X, Where X- mass concentration of the sum of saturated hydrocarbons C 12 - C 19, mg/m 3.
Note - The specified uncertainty corresponds to the relative error limits of ±25% with confidence probability P = 0.95.
2 Measurement method
Measurement of the mass concentration of the sum of hydrocarbons C 12 - C 19 is performed by gas chromatography. The substances to be determined are concentrated in a sampler with a carbon fiber sorbent of the “Carbon” type, desorbed with chloroform, and the resulting extract is analyzed on a chromatograph with a flame ionization detector. Quantitative analysis is carried out by absolute calibration using hexadecane. Identification of analytes is carried out by retention times.
3 Measuring instruments, auxiliary devices, reagents and materials
Laboratory gas chromatograph with flame ionization detector (minimum detectable amount of propane 2 ´ 10 -11 g/s);
Metal chromatographic column with a length of 2 m and an internal diameter of 3 mm;
Microsyringe “Gazochrom-101”, TU 65-2152-76 or MSh-1M, TU 6-2000 5E2.833.105;
Microsyringe MSh-10, TU 6-2000 5E2.833.106;
Laboratory scales VLR-200t, 2nd accuracy class, GOST 24104-2001;
Membrane meteorological barometer, GOST 23696-79;
Thermometer TL-2, TU 25-0221.003-88;
Aspirator PU-1Em, TU 4215-000-11696625-2003;
Volumetric diaphragm gas meter SGK - 1.6, State Register No. 17493-98;
All-glass syringes with a capacity of 100 cm 3, TU 64-1-1279-75;
Vacuum water jet pump, GOST 50-2 -79E;
Stopwatch, class-3, division value 0.2 sec, GOST 10696-75;
Sorption samplers with fibrous carbon sorbent (FCS) type “Carbon”, TU 1910-012-32847229-97;
Semi-vacuum rubber tube, type 1, GOST 5496-77;
Water bath, TU 1910-012-32847229-97;
Pipettes 2-1-2-10, 2-1-2-5, 4-2-2-2, 4-2-2-1, 4-2-2-0.1, GOST 29227-91;
Ampoule for biological research with a capacity of 1 - 5 cm 3, GOST 19803-86 or vials with a hole in the lid and a pierced Teflon gasket, volume 2, 4, 8 ml (NPAC "Ekolan", Moscow);
Nitrogen gas, high purity, TU 301-07-25-89;
Air for powering industrial devices and automation equipment, class 0 (or 1) according to GOST 14433-88;
Hydrogen gas, high purity, TU 301-07-27-90;
Nozzle: N-AW chromato (or inerton) fraction 0.20 - 0.25 mm, liquid-impregnated silicone 30 (SE-30), 5% by weight of the carrier (Czech Republic);
Hexadecane, TU 2631-007-45579693-2001;
Chloroform, chemically pure, TU 2631-001-29483781-2004;
Hardware and software complex "Polychrome" for receiving and processing chromatographic information or measuring magnifying glass, GOST 25706-83;
Measuring ruler, metal, with a division value of 1 mm, GOST 427-75.
NOTE
1. It is allowed to use other measuring instruments with an accuracy class not lower than those specified in the list, and other equipment with similar characteristics.
2. All measuring instruments must be verified in accordance with regulatory and technical documentation.
3. The reagents used must have passports or certificates confirming their suitability.
4 Safety requirements
When performing measurements of the mass concentration of the sum of hydrocarbons C 12 - C 19, it is necessary to comply with the safety requirements:
Safe work on a gas chromatograph, set out in the “Occupational Safety Instructions for the Operation of All Types of Chromatographs” and in the “Basic Safety Rules for Work in Chemical Laboratories”;
Safety precautions when working with chemical reagents in accordance with GOST 12.1.018 -86 and GOST 12.1.007-76 SSBT;
Electrical safety when working with electrical installations in accordance with GOST 12.1.019-79 SSBT;
When working with gases in pressure cylinders, the “Rules for the Design and Safe Operation of Pressure Vessels” approved by Gosgortekhnadzor must be observed;
The room must meet the requirements in accordance with GOST 12.1.004-91 and be provided with fire extinguishing means in accordance with GOST 12.4.009-83;
Organization of occupational safety training for workers should be carried out in accordance with the requirements of GOST 12.0.004-90.
5 Operator qualification requirements
Persons who have a higher or secondary specialized chemical education or experience working on any chromatograph and in a chemical laboratory, who have undergone appropriate instruction, have mastered the method during training and have met the operational control standards when performing error control procedures are allowed to perform measurements and process the results.
6 Measurement conditions
When sampling, the following conditions must be met:
Gas temperature from 10 to 80 °C;
Atmospheric pressure 84.0 - 106.7 kPa (630 - 800 mm Hg);
Relative humidity 30 - 95%
When performing measurements in the laboratory in accordance with GOST 15150-69, the following conditions must be met:
Air temperature 25 ± 10 °C;
Atmospheric pressure from 97.3 to 104.7 kPa (from 730 to 780 mm Hg);
Air humidity no more than 80% at a temperature of +25 °C;
Mains voltage 220 ± 10 V;
AC frequency 50±1Hz
Conditions for performing measurements on a chromatograph:
|
column length, m |
|
|
internal diameter of the column, mm |
|
|
programming the temperature of the column thermostat, C/min |
|
|
column thermostat temperature, °C |
|
|
evaporator temperature, °C |
|
|
carrier gas consumption, cm 3 /min |
|
|
hydrogen consumption, cm 3 /min |
|
|
air flow, cm 3 /min |
|
|
volume of injected sample, mm 3 |
|
|
chart tape speed, cm/min (for manual processing) |
|
|
ratio of the peak height of the target substance to noise is not less than |
Optimal conditions for performing measurements on a chromatograph are selected, under which the separation coefficient of the peaks of normal hydrocarbons C 11 and C 12 is is at least 1.5.
The separation coefficient (R) is calculated using the formula:
Where: ΔL- distance between peak peaks in the chromatogram, min;
b 1, b 2- width of peaks at mid-height, min.
The approximate values for the retention times of hydrocarbons under the above conditions for performing measurements on a chromatograph are:
|
Substance |
|
7 Preparing to take measurements
7.1 Preparation of the chromatograph
The chromatograph is prepared for operation in accordance with the operating instructions for the device.
The chromatographic column is washed using a water-jet pump sequentially with water, ethyl alcohol, acetone, dried in a stream of air and filled with a ready-made packing: N-AW chromato with applied liquid phase silicone 30 (SE-30), 5% by weight of the carrier.
The filled column is installed in the chromatograph thermostat and, without connecting to the detector, is conditioned in a flow of carrier gas, increasing the temperature from 60 to 250 °C at a rate of 2 °C per minute. The column is kept in isothermal mode at the final temperature for two hours. The column is then cooled to room temperature and connected to the detector.
7.2 Solvent preparation
Chloroform, used in measurements as a solvent for the desorption of hydrocarbons from the sorbent, is checked for the absence of impurities that coincide in retention times with hydrocarbons C 12 - C 19. If such impurities are present, take a new batch of chloroform and test it. The operating scale of low currents of the chromatograph must correspond to the maximum sensitivity of the device.
7.3 Chromatograph calibration
The chromatograph is calibrated against hexadecane using the absolute calibration method using a series of calibration solutions.
7.3.1 Preparation of calibration solutions
To prepare a calibration solution with the maximum concentration of hexadecane (solution No. 1), 100 to 150 mg of hexadecane is added to a pre-weighed volumetric flask with a capacity of 50 cm 3 with a ground-in stopper and weighed again. The weighing results are recorded to the fourth decimal place. Then pour about 25 - 30 cm 3 of chloroform into the flask, mix, and bring the contents of the flask to the mark with chloroform. The mass concentration of hexadecane in calibration source solution No. 1 (C and, mg/cm 3) is calculated using the formula:
Where: m- mass of hexadecane sample, mg;
V- flask capacity, cm 3.
The solution can be stored in the refrigerator for no more than 3 days.
From the prepared calibration initial solution No. 1 with a mass concentration of hexadecane 2 - 3 mg/cm3, the remaining 4 samples for calibration (CG) are prepared by volumetric dilution. To do this, the volumes of initial solution No. 1 specified in accordance with Table 2 are added with pipettes of appropriate capacity into four 10 cm 3 volumetric flasks with ground-in stoppers and adjusted to the mark with chloroform.
Table 2.
The procedure for preparing samples for calibration (CG)
|
Volume of the initial solution of hexadecane in chloroform, cm 3 |
|||||
|
Mass concentration of hexadecane in the calibration solution, mg/cm3 |
from 2.0 to 3.0 |
from 1.0 to 1.5 |
from 0.5 to 0.75 |
from 0.1 to 0.15 |
from 0.01 to 0.015 |
Mass concentration of hexadecane in the i-th sample for calibration, With or,i, mg/cm 3, found by the formula:
Where: C and- mass concentration of hexadecane in initial solution No. 1, mg/cm 3 ;
V and i- volume of the initial calibration solution No. 1, taken to prepare the i-th sample for calibration, cm 3;
10 - flask capacity, cm 3;
i- index indicating the exhaust gas number.
Calibration solutions are used immediately after their preparation.
7.3.2 Determination of the calibration factor
Using a microsyringe, washed 8-10 times with the analyzed calibration solution, a 1 mm3 sample is taken and introduced into the chromatograph evaporator. The sample should be taken very carefully and ensure that there are no air bubbles in it. Each injection is repeated 3 times, obtaining three chromatograms of each sample for calibration. Analyze 5 calibration solutions. An example of a chromatogram is shown in Fig. 1.
The chromatograms are processed using the Polychrome program.
For each calibration point (calibration solution), calculate the average value of the hexadecane peak area (mV×s):
Where: q- dosage number;
n- number of dosages ( n = 3).
The peak area values obtained with three dosages are considered acceptable if they satisfy the condition:
Where Si,max- maximum value of the peak area at the i-th calibration point, mV×s,
S i , min- minimum value of the peak area of the i-th calibration point, mV×s,
r s- standard, % (permissible relative discrepancy between three peak area values at P = 0.95),
r s = 10 %.
Calculate the calibration coefficient TOi, mg/cm 3 mV×s, for hexadecane at the i-th calibration point s according to the formula:
Where: C i- mass concentration of hexadecane in the i-th sample for calibration (OG), mg/cm 3 (according to Table 1);
Calculate the average calibration factor for hexadecane TO, mg/cm 3 mV×s, according to the formula:
The values of calibration coefficients obtained for five calibration points are considered acceptable if the following conditions are met:
1) if the inequality is satisfied:
Where TOi, max- maximum calibration coefficient of the i-th exhaust gas;
К i, min- minimum calibration coefficient of the i-th exhaust gas;
r to- standard, % (permissible relative discrepancy of five calibration coefficients at P = 0.95);
r to= 10 %
2) if there is no monotonic increase or decrease in calibration coefficients (from the 1st to the 5th calibration point).
Calibration must be carried out when a new batch of reagents is received, the sorbent in the chromatographic column or other elements of the chromatographic system is replaced, as well as when the results of monitoring the calibration coefficient according to clause 10.1 are negative.
8 Taking measurements
8.1 Sampling
Sampling of atmospheric air in the sanitary protection zone is carried out in accordance with the requirements of RD 52.04.186-89 “Guidelines for the control of air pollution”.
Air sampling in the working area is carried out in accordance with the requirements of GOST 12.1.005-88 (General sanitary and hygienic requirements for air in the working area). Sampling is carried out within 15 minutes. During this period, three consecutive samples are taken.
The sampling time for industrial emissions in accordance with the requirements of GOST 17.2.3.02-78 should be 20 minutes. At specially equipped points of the gas duct, one or several samples are taken sequentially (depending on the sampling time, up to three samples can be taken). For small sample volumes, the time interval between the start of the first sample and the end of the last sample should also be 20 minutes. Each sample is analyzed in accordance with this procedure. The results obtained are averaged.
Samples are taken into a disposable sampler with a fibrous carbon sorbent at an aspiration rate of 0.2 - 0.3 dm 3 /min. The sample volume is selected taking into account the expected concentration of hydrocarbons in the analyzed air from 0.2 dm 3 to 90 dm 3 (see Table 3).
Approximate values of the volume of gas sample taken depending on the expected concentration of C 12 - C 19 hydrocarbons in emissions are presented in Table 3.
Table 3
|
Approximate ranges of concentration of the amount of hydrocarbons C 12 - C 19, mg/m 3 |
||
To take samples of industrial emissions, one end of the sampler is connected end-to-end with a rubber hose to a metal (or glass) tube with a diameter of 4 - 6 mm, which is inserted into the center of the flue. The other end of the sampler is connected to an aspirator (Fig. 2 of the Appendix) or, for manual sampling, to a glass medical syringe with a capacity of 100 cm 3 and a gas sample is taken.
During the sampling process, temperature, atmospheric pressure and vacuum at the inlet of the sampling device are measured.
After collecting gas samples, the samplers are placed in test tubes with ground stoppers, labeled and delivered to the laboratory. Samples can be stored in the refrigerator for 7 days. In each batch of samples taken, at least two samplers are left without samples to control the background of the sorbent.
Calculate the volume of the sampled gas emissions ( Vt) in dm 3:
Vt = W × τ (9)
Where τ - sampling time, min.,
W- volumetric gas flow rate during sampling, dm 3 /min.
The selected sample volume is brought to normal conditions (0 °C, 101.3 kPa) for industrial emissions and atmospheric air in the sanitary protection zone (formula 10") or standard conditions (20 °C, 101.3 kPa) for air in the working area ( formula 10"):
Where V 0- volume of gas selected for analysis and reduced to normal (standard) conditions dm 3;
R- atmospheric pressure, kPa;
ΔР- vacuum (-), pressure (+) in the gas duct, kPa;
t- gas temperature at the inlet of the sampling device, °C.
8.2 Sample preparation and analysis
To extract hydrocarbons, the sorbent is transferred from the tube into an ampoule with a wide neck of 1 - 5 cm 3 (or into a vial). Then 1 cm 3 of chloroform is added there, the ampoule is closed with a silicone rubber stopper and by gentle shaking the sorbent is completely wetted, which then sinks and becomes compacted at the bottom of the ampoule. The duration of desorption sufficient for quantitative determination is 1.5 hours. The resulting extract is analyzed. To do this, use a 1 mm 3 microsyringe, washed 8-10 times with the extract, take 1 mm 3 of the extract and inject it into the chromatograph evaporator in accordance with the conditions of clause 6. When filling the microsyringe, it is necessary to ensure that there are no air bubbles in the portions of the extract. The input is carried out at least twice, recording the peak areas, which, in terms of retention time, are in the range of peak retention times from dodecane to nonadecane (C 12 - C 19).
If the relative retention times of hydrocarbons C 11 - C 12 specified in clause 6 change by more than 30%, it is necessary to re-prepare the chromatographic column in accordance with clause 7.1.
The chromatogram of the sample extract is shown in Fig. 3 Applications.
9 Processing of measurement results
9.1 Calculate the total area of the hydrocarbon peaks C 12 - C 19 for the first injection of the extract sample S 1 Σ, mV×s,
where - are the areas of individual peaks of hydrocarbons C 12 - C 19 at the first injection of the extract sample, mV×s.
Similarly, calculate the total area of the hydrocarbon peaks C 12 - C 19 for the second injection of the extract sample S 2 Σ, mV×s.
Calculate the average value of the total area of hydrocarbon peaks C 12 - C 19 S Σ, mB×s.
The values of the total peak areas obtained with two inputs are considered acceptable if they satisfy the condition:
Where d- standard corresponding to probability 0.95, d= 12% at P = 0.95.
Note - If, when condition (12) is regularly met, there is a one-time excess of the standard d, then proceed in accordance with the recommendations of clause 5.2 of GOST R ISO 5725-6-2002: obtain 2 additional chromatograms of the extract, calculate a new average value of the total area of hydrocarbon peaks (C 12 - C 19) using four chromatograms and checking the acceptability of four parallel determinations with the standardd 1 = 16 %.
9.2. Mass of the sum of hydrocarbons C 12 - C 19 M, mg, taken by the sampler, is calculated using the formula:
M = K × S ∑ × v e (13),
Where v e- extract volume, cm3.
9.3. Mass concentration of the total hydrocarbons C 12 - C 19 in the sample X, mg/m3, calculated using the formula:
Where V 0- volume of air sample taken for analysis, reduced to normal (standard) conditions (according to formulas 10), dm 3.
10. Monitoring the accuracy of measurement results
10.1. Control of the calibration coefficient
10.1.1 The calibration coefficient is monitored periodically. The recommended frequency of monitoring is at least once a quarter. With more frequent monitoring, it is recommended to register the results on Shewhart cards in accordance with clause 6.2.4.1 GOST R ISO 5725-6-2002.
10.1.2 The control is carried out using a control solution, which is prepared and analyzed in the same way as the calibration solution number 3 in accordance with clause 7.3.
The result is considered satisfactory provided
Where λ counter- standard for control of the calibration coefficient, %.
λ counter= 7% at P = 0.95.
If this condition is not met, operations are carried out to establish a new calibration coefficient in accordance with clause 7.3.
10.2 Verification of the correctness of measurement results
Control is carried out by analyzing a model mixture prepared on a thermal diffusion generator equipped with microflow sources of dodecane (No. 06.04.017) * or tridecane (No. 06.04.034) * IBYAL. 419319.013 TU-95. The mass concentration of the analytes in the mixture must be in the MVI range and set with a relative error of no more than ± 8%.
* MI 2590-2004 “GSI Reference materials. Catalog 2004-2005"
Carrying out measurements and processing their results are carried out in accordance with paragraphs. 8, 9 methods. The mass concentration of the target substance in the control mixture is measured twice.
The control results are considered positive if the following conditions are met:
X z, X- specified and measured value of the mass concentration of the substance in the control mixture;
N= 20% at P = 0.95:
11. Registration of measurement results
The measurement result is written in the form: ( X±U) mg/m3, where U = 0.25×X, mg/m3.
If, when monitoring the content of the total hydrocarbons C 12 - C 19, several samples are taken and analyzed, then the resulting mass concentration values are averaged.
Application
Rice. 1 Chromatogram of a model mixture of hydrocarbons in chloroform:
1 - chloroform; 2 - C 13 H 28; 3 - C 14 H 30; 4 - C 15 H 32; 5 - C 16 H 34.
Rice. 2 Sampling installation diagram
1 - gas flue, 2- sampling probe, 3 - sorption tube, 4 - pressure gauge, 5 - thermometer, 6 - gas meter, 7 - aspirator.
Rice. 3. Chromatogram of the sample extract, hydrocarbons C 12 - C 19, taken from the fuel oil storage facility at 50 ° C (ΣC c 12 - c 19 = 26.7 mg/m 3)
Hydrocarbons in whose molecules the atoms are connected by single bonds and which correspond to the general formula C n H 2 n +2.
In alkane molecules, all carbon atoms are in a state of sp 3 hybridization. This means that all four hybrid orbitals of the carbon atom are identical in shape, energy and are directed to the corners of an equilateral triangular pyramid - a tetrahedron. The angles between the orbitals are 109° 28′.
Almost free rotation is possible around a single carbon-carbon bond, and alkane molecules can take on a wide variety of shapes with angles at the carbon atoms close to tetrahedral (109° 28′), for example, in the molecule n-pentane.
It is especially worth recalling the bonds in alkane molecules. All bonds in the molecules of saturated hydrocarbons are single. The overlap occurs along the axis,
connecting the nuclei of atoms, i.e. these are σ bonds. Carbon-carbon bonds are non-polar and poorly polarizable. The length of the C-C bond in alkanes is 0.154 nm (1.54 10 - 10 m). C-H bonds are somewhat shorter. The electron density is slightly shifted towards the more electronegative carbon atom, i.e. the C-H bond is weakly polar.
The absence of polar bonds in the molecules of saturated hydrocarbons leads to the fact that they are poorly soluble in water and do not interact with charged particles (ions). The most characteristic reactions for alkanes are those involving free radicals.
Homologous series of methane
Homologues- substances that are similar in structure and properties and differ by one or more CH 2 groups.
Isomerism and nomenclature
Alkanes are characterized by so-called structural isomerism. Structural isomers differ from each other in the structure of the carbon skeleton. The simplest alkane, which is characterized by structural isomers, is butane. 
Basics of nomenclature
1. Selection of the main circuit. The formation of the name of a hydrocarbon begins with the definition of the main chain - the longest chain of carbon atoms in the molecule, which is, as it were, its basis.
2. Numbering of atoms of the main chain. The atoms of the main chain are assigned numbers. The numbering of the atoms of the main chain begins from the end to which the substituent is closest (structures A, B). If the substituents are located at an equal distance from the end of the chain, then numbering starts from the end at which there are more of them (structure B). If different substituents are located at equal distances from the ends of the chain, then numbering begins from the end to which the senior one is closest (structure D). The seniority of hydrocarbon substituents is determined by the order in which the letter with which their name begins appears in the alphabet: methyl (-CH 3), then ethyl (-CH 2 -CH 3), propyl (-CH 2 -CH 2 -CH 3 ) etc.
Please note that the name of the substituent is formed by replacing the suffix -an with the suffix - silt in the name of the corresponding alkane.
3. Formation of the name. At the beginning of the name, numbers are indicated - the numbers of the carbon atoms at which the substituents are located. If there are several substituents at a given atom, then the corresponding number in the name is repeated twice separated by a comma (2,2-). After the number, the number of substituents is indicated with a hyphen ( di- two, three- three, tetra- four, penta- five) and the name of the substituent (methyl, ethyl, propyl). Then, without spaces or hyphens, the name of the main chain. The main chain is called a hydrocarbon - a member of the homologous series of methane ( methane CH 4, ethane C 2 H 6, propane C 3 H 8, C 4 H 10, pentane C 5 H 12, hexane C 6 H 14, heptane C 7 H 16, octane C 8 H 18, nonan S 9 H 20, dean C 10 H 22).
Physical properties of alkanes
The first four representatives of the homologous series of methane are gases. The simplest of them is methane - a colorless, tasteless and odorless gas (the smell of “gas”, when you smell it, you need to call 04, is determined by the smell of mercaptans - sulfur-containing compounds specially added to methane used in household and industrial gas appliances so that people , located next to them, could detect the leak by smell).
Hydrocarbons of composition from C 4 H 12 to C 15 H 32 are liquids; heavier hydrocarbons are solids. The boiling and melting points of alkanes gradually increase with increasing carbon chain length. All hydrocarbons are poorly soluble in water; liquid hydrocarbons are common organic solvents.
Chemical properties of alkanes
Substitution reactions.
The most characteristic reactions for alkanes are free radical substitution reactions, during which a hydrogen atom is replaced by a halogen atom or some group. Let us present the equations of characteristic reactions halogenation: 
In case of excess halogen, chlorination can go further, up to the complete replacement of all hydrogen atoms with chlorine: 
The resulting substances are widely used as solvents and starting materials in organic syntheses.
Dehydrogenation reaction(hydrogen abstraction).
When alkanes are passed over a catalyst (Pt, Ni, Al 2 0 3, Cr 2 0 3) at high temperatures (400-600 ° C), a hydrogen molecule is eliminated and an alkene is formed:
Reactions accompanied by the destruction of the carbon chain.
All saturated hydrocarbons burn to form carbon dioxide and water. Gaseous hydrocarbons mixed with air in certain proportions can explode.
1. Combustion of saturated hydrocarbons is a free radical exothermic reaction, which is very important when using alkanes as fuel:
In general, the combustion reaction of alkanes can be written as follows:
2. Thermal splitting of hydrocarbons.
The process occurs via a free radical mechanism. An increase in temperature leads to homolytic cleavage of the carbon-carbon bond and the formation of free radicals.
These radicals interact with each other, exchanging a hydrogen atom, to form an alkane molecule and an alkene molecule:
Thermal decomposition reactions underlie the industrial process of hydrocarbon cracking. This process is the most important stage of oil refining.
3. Pyrolysis. When methane is heated to a temperature of 1000 °C, methane pyrolysis begins - decomposition into simple substances: 
When heated to a temperature of 1500 °C, the formation of acetylene is possible:
4. Isomerization. When linear hydrocarbons are heated with an isomerization catalyst (aluminum chloride), substances with a branched carbon skeleton are formed: 
5. Aromatization. Alkanes with six or more carbon atoms in the chain cyclize in the presence of a catalyst to form benzene and its derivatives: 
Alkanes enter into reactions that proceed according to the free radical mechanism, since all carbon atoms in alkane molecules are in a state of sp 3 hybridization. The molecules of these substances are built using covalent nonpolar C-C (carbon-carbon) bonds and weakly polar C-H (carbon-hydrogen) bonds. They do not contain areas with increased or decreased electron density, or easily polarizable bonds, i.e., such bonds in which the electron density can shift under the influence of external factors (electrostatic fields of ions). Consequently, alkanes will not react with charged particles, since the bonds in alkane molecules are not broken by the heterolytic mechanism. 
In accordance with Article 4 1 of the Federal Law "On Environmental Protection", approve the attached list of pollutants in respect of which state regulatory measures in the field of environmental protection are applied.
Chairman of the Government
Russian Federation
D.Medvedev
List of pollutants subject to state regulation in the field of environmental protection
I. For atmospheric air
1. Nitrogen dioxide
2. Nitrogen oxide
3. Nitric acid
4. Ammonia
5. Ammonium nitrate (ammonium nitrate)
6. Barium and its salts (in terms of barium)
7. Benzopyrene
8. Boric acid (orthoboric acid)
9. Vanadium five oxide
10. PM10 suspended particles
11. Suspended particles PM2.5
12. Suspended solids
13. Hydrogen bromide (hydrobromide)
14. Arsenic hydrogen (arsine)
15. Hydrogen phosphorous (phosphine)
16. Hydrogen cyanide
17. Sulfur hexafluoride
18. Dialuminum trioxide (in terms of aluminum)
19. Dioxins (polychlorinated dibenzo-p-dioxins and dibenzofurans) in terms of 2,3,7,8-tetrachlorodibenzo-1,4-dioxin
20. Diethylmercury (in terms of mercury)
21. Iron trichloride (in terms of iron)
22. Solid fuel ash
23. TPP fuel oil ash (in terms of vanadium)
24. Cadmium and its compounds
25. Sodium carbonate (disodium carbonate)
26. Terephthalic acid
27. Cobalt and its compounds (cobalt oxide, cobalt salts in terms of cobalt)
28. Nickel, nickel oxide (in terms of nickel)
29. Nickel soluble salts (in terms of nickel)
30. Magnesium oxide
31. Manganese and its compounds
32. Copper, copper oxide, copper sulfate, copper chloride (in terms of copper)
33. Methane
34. Methyl mercaptan, ethyl mercaptan
35. Arsenic and its compounds, except arsenic hydrogen
36. Ozone
37. Inorganic dust with a silicon content of less than 20, 20-70, and also more than 70 percent
38. Mercury and its compounds, except diethylmercury
39. Lead and its compounds, except tetraethyl lead, calculated as lead
40. Hydrogen sulfide
41. Carbon disulfide
42. Sulfuric acid
43. Sulfur dioxide
44. Tellurium dioxide
45. Tetraethyl lead
46. Carbon oxide
47. Phosgene
48. Phosphoric anhydride (diphosphorus pentoxide)
49. Gaseous fluorides (hydrofluoride, silicon tetrafluoride) (in terms of fluorine)
50. Solid fluorides
51. Hydrogen fluoride, soluble fluorides
52. Chlorine
53. Hydrogen chloride
54. Chloroprene
55. Chrome (Cr 6+)
Volatile organic compounds (VOCs) (except methane)
Saturated hydrocarbons
56. Saturated hydrocarbons C1-C-5 (excluding methane)
57. Saturated hydrocarbons C6-C10
58. Saturated hydrocarbons C12-C-19
59. Cyclohexane
Unsaturated hydrocarbons
60. Amylenes (mixture of isomers)
61. Butylene
62. 1,3-butadiene (divinyl)
63. Heptene
64. Propylene
65. Ethylene
Aromatic hydrocarbons
66. Alpha methylstyrene
67. Benzene
68. Dimethylbenzene (xylene) (mixture of meta-, ortho- and para isomers)
69. Isopropylbenzene (cumene)
70. Methylbenzene (toluene)
71. Furniture solvent (AMP-3) (toluene control)
72. 1,3,5-Trimethylbenzene (mesitylene)
73. Phenol
74. Ethylbenzene (styrene)
Aromatic polycyclic hydrocarbons
75. Naphthalene
Halogenated hydrocarbons
76. Bromobenzene
77. 1-Bromoheptane (heptyl bromide)
78. 1-Bromodecane (decyl bromide)
79. 1-Bromo-3-methylbutane (isoamyl bromide)
80. 1-Bromo-2-methylpropane (isobutyl bromide)
81. 1-Bromopentane (amyl bromide)
82. 1-Bromopropane (propyl bromide)
83. 2-Bromopropane (isopropyl bromide)
84. Dichloroethane
85. Dichlorofluoromethane (freon 21)
86. Difluorochloromethane (freon 22)
87. 1,2-Dichloropropane
88. Methylene chloride
89. Carbon tetrachloride
90. Tetrachlorethylene (perchlorethylene)
91. Tetrafluoroethylene
92. Trichloromethane (chloroform)
93. Trichlorethylene
94. Tribromomethane (bromoform)
95. Carbon tetrachloride
96. Chlorobenzene
97. Chloroethane (ethyl chloride)
98. Epichlorohydrin
Alcohols and phenols
99. Hydroxymethylbenzene (cresol, mixture of isomers: ortho-, meta-, para-)
100. Amyl alcohol
101. Butyl alcohol
102. Isobutyl alcohol
103. Isooctyl alcohol
104. Isopropyl alcohol
105. Methyl alcohol
106. Propyl alcohol
107. Ethyl alcohol
108. Cyclohexanol
Ethers
109. Terephthalic acid dimethyl ester
110. Dinyl (mixture of 25 percent diphenyl and 75 percent diphenyl oxide)
111. Diethyl ether
112. Methylal (dimethoxymethane)
113. Ethylene glycol monoisobutyl ether (butyl cellosolve)
Esters (except phosphoric acid esters)
114. Butyl acrylate (butyl ester of acrylic acid)
115. Butyl acetate
116. Vinyl acetate
117. Methyl acrylate (methylprop-2enoate)
118. Methyl acetate
119. Ethyl acetate
Aldehydes
120. Acrolein
121. Oily aldehyde
122. Acetaldehyde
123. Formaldehyde
Ketones
124. Acetone
125. Acetophenone (methyl phenyl ketone)
126. Methyl ethyl ketone
127. Wood alcohol solvent grade A (acetone ester) (acetone control)
128. Wood alcohol solvent grade E (ether-acetone) (acetone control)
129. Cyclohexanone
Organic acids
130. Maleic anhydride (vapor, aerosol)
131. Acetic anhydride
132. Phthalic anhydride
133. Dimethylformamide
134. Epsilon-caprolactam (hexahydro-2H-azepin-2-one)
135. Acrylic acid (prop-2-enoic acid)
136. Valeric acid
137. Nylon acid
138. Butyric acid
139. Propionic acid
140. Acetic acid
141. Terephthalic acid
142. Formic acid
Organic oxides and peroxides
143. Isopropylbenzene hydroperoxide (cumene hydroperoxide)
144. Propylene oxide
145. Ethylene oxide
146. Dimethyl sulfide
Amines
147. Aniline
148. Dimethylamine
149. Triethylamine
Nitro compounds
150. Nitrobenzene
Other nitrogen-containing
151. Acrylonitrile
152. N, N1-Dimethylacetamide
153. Toluene diisocyanate
Technical mixtures
154. Gasoline (petroleum, low sulfur in terms of carbon)
155. Shale gasoline (in terms of carbon)
156. Kerosene
157. Mineral oil
158. Turpentine
159. Solvent naphtha
160. White spirit
Radioactive isotopes in elemental form and as compounds
161. Americium (Am) - 241
162. Argon (Ar) - 41
163. Barium (Ba) - 140
164. Hydrogen (H) - 3
165. Gallium (Ga) - 67
166. Europium (Eu) - 152
167. Europium (Eu) - 154
168. Europium (Eu) - 155
169. Iron (Fe) - 55
170. Iron (Fe) - 59
171. Gold (Au) - 198
172. Indium (In) - 111
173. Iridium (Ir) - 192
174. Iodine (I) - 123
175. Iodine (I) - 129
176. Iodine (I) - 131
177. Iodine (I) - 132
178. Iodine (I) - 133
179. Iodine (I) - 135
180. Potassium (K) - 42
181. Calcium (Ca) - 45
182. Calcium (Ca) - 47
183. Cobalt (Co) - 57
184. Cobalt (Co) - 58
185. Cobalt (Co) - 60
186. Krypton (Kr) - 85
187. Krypton (Kr) - 85m
188. Krypton (Kr) - 87
189. Krypton (Kr) - 88
190. Krypton (Kr) - 89
191. Xenon (Xe) - 127
192. Xenon (Xe) - 133
193. Xenon (Xe) - 133m
194. Xenon (Xe) - 135
195. Xenon (Xe) - 135m
196. Xenon (Xe) - 137
197. Xenon (Xe) - 138
198. Curium (Cm) - 242
199. Curium (Cm) - 243
200. Curium (Cm) - 244
201. Lanthanum (La) - 140
202. Manganese (Mn) - 54
203. Molybdenum (Mo) - 99
204. Sodium (Na) - 22
205. Sodium (Na) - 24
206. Neptunium (Np) - 237
207. Nickel (Ni) - 63
208. Niobium (Nb) - 95
209. Plutonium (Pu) - 238
210. Plutonium (Pu) - 239
211. Plutonium (Pu) - 240
212. Plutonium (Pu) - 241
213. Polonium (Po) - 210
214. Praseodymium (Pr) - 144
215. Promethium (Pm) - 147
216. Radium (Ra) - 226
217. Radon (Rn) - 222
218. Mercury (Hg) - 197
219. Ruthenium (Ru) - 103
220. Ruthenium (Ru) - 106
221. Lead (Pb) - 210
222. Selenium (Se) - 75
223. Sulfur (S) - 35
224. Silver (Ag) - 110m
225. Strontium (Sr) - 89
226. Strontium (Sr) - 90
227. Antimony (Sb) - 122
228. Antimony (Sb) - 124
229. Antimony (Sb) - 125
230. Thallium (Tl) - 201
231. Tellurium (Te) - 123m
232. Technetium (Tc) - 99
233. Technetium (Tc) - 99m
234. Thorium (Th) - 230
235. Thorium (Th) - 231
236. Thorium (Th) - 232
237. Thorium (Th) - 234
238. Carbon (C) - 14
239. Uranium (U) - 232
240. Uranium (U) - 233
241. Uranium (U) - 234
242. Uranium (U) - 235
243. Uranium (U) - 236
244. Uranium (U) - 238
245. Phosphorus (P) - 32
246. Chlorine (Cl) - 36
247. Chrome (Cr) - 51
248. Cesium (Cs) - 134
249. Cesium (Cs) - 137
250. Cerium (Ce) - 141
251. Cerium (Ce) - 144
252. Zinc (Zn) - 65
253. Zirconium (Zr) - 95
254. Erbium (Er) - 169
II. For water bodies
1. Acrylonitrile (acrylic acid nitrile)
2. Aluminum
3. Alkylbenzylpyridinium chloride
4. Alkylsulfonates
5. Ammonium ion
6. Ammonia
7. Aniline (aminobenzene, phenylamine)
8. AOX (absorbable organohalogen compounds)
9. Sodium acetate
10. Acetaldehyde
11. Acetone (dimethylketone, propanone)
12. Acetonitrile
13. Barium
14. Beryllium
15. Benzopyrene
16. Benzene and its homologues
17. Bor
18. Boric acid
19. Bromodichloromethane
20. Bromide anion
21. Butanol
22. Butyl acetate
23. Butyl methacrylate
24. Vanadium
25. Vinyl acetate
26. Vinyl chloride
27. Bismuth
28. Tungsten
29. Hexane
30. Hydrazine hydrate
31. Glycerin (propane-1,2,3-triol)
32. Dibromochloromethane
33. 1,2-Dichloroethane
34. 1,4-Dihydroxybenzene (hydroquinone)
35. 2,6-Dimethylaniline
36. Dimethylamine (N-methylmethanamine)
37. Dimethyl mercaptan (dimethyl sulfide)
38. 2,4-Dinitrophenol
39. Dimethylformamide
40. o-Dimethyl phthalate (dimethylbenzene-1,2-dicarbonate)
41. 1,2-Dichloropropane
42. Cis-1,3-dichloropropene
43. Trans-1,3-dichloropropene
44. 2,4-Dichlorophenol (hydroxydichlorobenzene)
45. Dodecylbenzene
46. Dichloromethane (methylene chloride)
47. Iron
48. Cadmium
49. Potassium
50. Calcium
51. Caprolactam (hexahydro-2H-azepin-2-one)
52. Urea (urea)
53. Cobalt
54. Silicon (silicates)
55. o-Cresol (2-methylphenol)
56. p-Cresol (4-methylphenol)
57. Xylene (o-xylene, m-xylene, p-xylene)
58. Lignin sulfonic acids
59. Lignosulfonates
60. Lithium
61. Magnesium
62. Manganese
63. Copper
64. Methanol (methyl alcohol)
65. Methyl acrylate (methylprop-2-enoate, acrylic acid methyl ester)
66. Methanethiol (methyl mercaptan)
67. Methyl acetate
68. Metol (1-hydroxy-4-(methylamino)benzene)
69. Molybdenum
70. Monoethanolamine
71. Arsenic and its compounds
72. Sodium
73. Naphthalene
74. Petroleum products (petroleum)
75. Nickel
76. Nitrate anion
77. Nitrite anion
78. Nitrobenzene
79. Tin and its compounds
80. 1,1,2,2,3-pentachloropropane
81. Pentachlorophenol
82. Pyridine
83. Polyacrylamide
84. Propanol
85. Rodanide ion
86. Rubidium
87. Mercury and its compounds
88. Lead
89. Selenium
90. Silver
91. Carbon disulfide
92. ASPA (anionic synthetic surfactants)
93. SCSAS (cationic synthetic surfactants)
94. Non-ionic surfactants (non-ionic synthetic surfactants)
95. Turpentine
96. Styrene (ethenylbenzene, vinylbenzene)
97. Strontium
98. Sulfate anion (sulfates)
99. Sulfides
100. Sulfite anion
101. Antimony
102. Thallium
103. Tellurium
104. 1,1,1,2-tetrachloroethane
105. Tetrachlorethylene (perchlorethylene)
106. Carbon tetrachloride (carbon tetrachloride)
107. Tetraethyl lead
108. Thiocarbamide (thiourea)
109. Thiosulfates
110. Titan
111. Toluene
112. Trilon-B (ethylenediaminetetraacetic acid disodium salt)
113. Triethylamine
114. Trichlorobenzene (sum of isomers)
115. 1,2,3-trichloropropane
116. 2,4,6-Trichlorophenol
117. Trichlorethylene
118. Acetic acid
119. Phenol, hydroxybenzene
120. Formaldehyde (methanal, formic aldehyde)
121. Phosphates (phosphorus)
122. Fluoride anion
123. Furfural
124. Free, dissolved chlorine and organochlorine compounds
125. Chlorate anion
126. Chlorobenzene
127. Chloroform (trichloromethane)
128. Chlorophenols
129. Chloride anion (chlorides)
130. Chromium trivalent
131. Hexavalent chromium
132. Cesium
133. Cyanide anion
134. Cyclohexanol
135. Zinc
136. Zirconium
137. Ethanol
138. Ethyl acetate
139. Ethylbenzene
140. Ethylene glycol (glycol, ethanediol-1,2)
Persistent organic pollutants
141. Aldrin (1,2,3,4,10,10-hexachloro-1,4,4a, 5,8,8a-hexahydro-1,4-endoexo-5,8-dimethanonaphthalene)
142. Atrazine (6-chloro-N-ethyl-N"-(1-methylethyl)-1,3,5-triazine-2,4-diamine)
143. Hexachlorobenzene
144. Hexachlorocyclohexane (alpha, beta, gamma isomers)
145. 2,4-D (2,4-dichlorophenoxyacetic acid and derivatives)
146. Dieldrin (1,2,3,4,10,10-hexachloro-exo-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-1,4-endo, exo-5,8-dimethanonaphthalene)
147. Dioxins
148. Captan (3a, 4, 7, 7a-tetrahydro-2-[(trichloromethyl)thio]-1n-isoindole-1, 3 (2n)-dione)
149. Karbofos (diethyl (dimethoxyphosphinothionyl)thiobutanedione)
150. 4,4"-DDT (p,p"-DDT, 4,4"-dichlorodiphenyltrichloromethylethane)
151. 4,4"-DDD (p,p"-DDD, 4,4"-dichlorodiphenyldichloroethane)
152. Prometrin (2,4-Bis(isopropylamino)-6-methylthio-sim-triazine)
153. Simazine (6-chloro-N, N"-diethyl-1,3,5-triazines-2,4-diamine)
154. Polychlorinated biphenyls (PCB 28, PCB 52, PCB 74, PCB 99, PCB 101, PCB 105, PCB 110, PCB 153, PCB 170)
155. Trifluralin (2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)aniline)
156. THAN (sodium trichloroacetate, TCA)
157. Fosalone (O,O-diethyl-(S-2,3-dihydro-6-chloro-2-oxobenzoxazol-3-ylmethyl)-dithiophosphate)
Microorganisms
158. Causative agents of infectious diseases
159. Viable cysts of pathogenic intestinal protozoa
160. Viable helminth eggs
161. Coli-phages
162. Common coliform bacteria
163. Thermotolerant coliform bacteria
Other pollutants
164. BOD 5
165. BOD full.
166. Suspended solids
167. Dry residue
168. COD
169. Americium (Am) - 241
170. Barium (Ba) - 140
171. Hydrogen (H) - 3
172. Gallium (Ga) - 67
173. Europium (Eu) - 152
174. Europium (Eu) - 154
175. Europium (Eu) - 155
176. Iron (Fe) - 55
177. Iron (Fe) - 59
178. Gold (Au) - 198
179. Indium (In) - 111
180. Iridium (Ir) - 192
181. Iodine (I) - 123
182. Iodine (I) - 129
183. Iodine (I) - 131
184. Iodine (I) - 132
185. Iodine (I) - 133
186. Iodine (I) - 135
187. Potassium (K) - 42
188. Calcium (Ca) - 45
189. Calcium (Ca) - 47
190. Cobalt (Co) - 57
191. Cobalt (Co) - 58
192. Cobalt (Co) - 60
193. Curium (Cm) - 242
194. Curium (Cm) - 243
195. Curium (Cm) - 244
196. Lanthanum (La) - 140
197. Manganese (Mn) - 54
198. Molybdenum (Mo) - 99
199. Sodium (Na) - 22
200. Sodium (Na) - 24
201. Neptunium (Np) - 237
202. Nickel (Ni) - 63
203. Niobium (Nb) - 95
204. Plutonium (Pu) - 238
205. Plutonium (Pu) - 239
206. Plutonium (Pu) - 240
207. Plutonium (Pu) - 241
208. Polonium (Po) - 210
209. Praseodymium (Pr) - 144
210. Promethium (Pm) - 147
211. Radium (Ra) - 226
212. Radon (Rn) - 222
213. Mercury (Hg) - 197
214. Ruthenium (Ru) - 103
215. Ruthenium (Ru) - 106
216. Lead (Pb) - 210
217. Selenium (Se) - 75
218. Sulfur (S) - 35
219. Silver (Ag) - 110m
220. Strontium (Sr) - 89
221. Strontium (Sr) - 90
222. Antimony (Sb) - 122
223. Antimony (Sb) - 124
224. Antimony (Sb) - 125
225. Thallium (Tl) - 201
226. Tellurium (Te) - 123m
227. Technetium (Tc) - 99
228. Technetium (Tc) - 99 m
229. Thorium (Th) - 230
230. Thorium (Th) - 231
231. Thorium (Th) - 232
232. Thorium (Th) - 234
233. Carbon (C) - 14
234. Uranium (U) - 232
235. Uranium (U) - 233
236. Uranium (U) - 234
237. Uranium (U) - 235
238. Uranium (U) - 236
239. Uranium (U) - 238
240. Phosphorus (P) - 32
241. Chlorine (Cl) - 36
242. Chrome (Cr) - 51
243. Cesium (Cs) - 134
244. Cesium (Cs) - 137
245. Cerium (Ce) - 141
246. Cerium (Ce) - 144
247. Zinc (Zn) - 65
248. Zirconium (Zr) - 95
249. Erbium (Er) - 169
III. For soils
1. Benzopyrene
2. Gasoline
3. Benzene
4. Vanadium
5. Hexachlorobenzene (HCB)
6. Glyphosate
7. Dicamba
8. Dimethylbenzenes (1,2-dimethylbenzene, 1,3-dimethylbenzene, 1,4-dimethylbenzene)
9. 1,1-di-(4-chlorophenyl) - 2,2,2-trichloroethane (DDT) and metabolites DDE, DDD
10. 2,2"-Dichlorodiethyl sulfide (mustard gas)
11. 2,4-D and derivatives (2,4-dichlorophenoxyacetic acid and its derivatives)
12. Cadmium
13. Cobalt
14. Malathion (karbofos)
15. Manganese
16. Copper
17. Methanal
18. Methylbenzene
19. (1-methylethenyl)benzene
20. (1-methylethyl)benzene
21. MSRA
22. Arsenic
23. Petroleum products
24. Nickel
25. Nitrates (by NO3)
26. Nitrites (by NO2)
27. O-(1,2,2-trimethylpropyl) methyl fluorophosphonate (soman)
28. O-(sarin)
29. O-Isobutyl-beta-p-diethylaminoethanethiol ester of methylphosphonic acid
30. Ammonium perchlorate
31. Parathion-methyl (metaphos)
32. Prometrin
33. PCB N 28 (2,4,4"-trichlorobiphenyl)
34. PCB N 52 (2,2",5,5"-tetrachlorobiphenyl)
35. PCB N 101 (2,2",4,5,5"-pentachlorobiphenyl)
36. PCB N 118 (2,3,4,4,5-pentachlorobiphenyl)
37. PCB N 138 (2,2I,3,4,4I,5-hexachlorobiphenyl)
38. PCB N 153 (2,2,4,4",5>5"-hexachlorobiphenyl)
39. PCB N 180 (2,2",3,4,4",5,5"-heptachlorobiphenyl)
40. PHC (toxaphene)
41. Inorganic mercury and organic mercury
42. Lead
43. Sulfuric acid (according to S)
44. Hydrogen sulfide (by S)
45. Sum of polyaromatic hydrocarbons
46. Antimony
47. Phenols
48. Phosphates (by P2O5)
49. Fluorine
50. Furan-2-carbaldehyde
51. 2-Chlorovinyldichloroarsine (lewisite)
52. Potassium chloride (by K2O)
53. Chlorobenzenes
54. Chlorophenols
55. Chromium trivalent
56. Chromium hexavalent
57. Zinc
58. Ethanal
59. Ethylbenzene
Radioactive isotopes in elemental form and as compounds
60. Plutonium (Pu) - 239
61. Plutonium (Pu) - 240
62. Strontium (Sr) - 90
63. Cesium (Cs) - 137
Molecules that contain only a single bond. These include alkanes and cycloparaffins; their features will be discussed in our material.
General formula of alkanes
Representatives of this class are characterized by the general formula SpH2n+2. Paraffins include all compounds that have an open chain, where the atoms are connected to each other by simple bonds. Due to the fact that under normal conditions aliphatic hydrocarbons are low-active compounds, they received their name “paraffins”. Let's find out some structural features of representatives of this class, the nature of the bonds in molecules, and areas of application.
Brief characteristics of methane
Methane can be mentioned as the simplest representative of this class. It is he who begins the aliphatic series of hydrocarbons. Let's identify its distinctive features.
Methane is, under normal conditions, a gaseous substance that is odorless and colorless. This compound is formed in nature during the decomposition of animals and plant organisms without the presence of atmospheric oxygen. For example, it was found in natural gas, so it is currently used in large quantities as a fuel in production and at home.
What chemical bond do these hydrocarbons have? Aliphatic, saturated organic compounds are covalent polar molecules.
The methane molecule has a tetrahedral molecule shape, the type of hybridization of carbon atoms in it is sp3, which corresponds to a bond angle of 109 degrees 28 minutes. It is for this reason that aliphatic hydrocarbons are chemically inactive compounds.
Features of methane homologues
In addition to methane, natural gas and oil contain other hydrocarbons that have a similar structure to it. The first four representatives of the homologous series of paraffins are in a gaseous aggregate state and have insignificant solubility in water.
As the value increases, an increase in the boiling and melting temperatures of CxHy is observed. There is a certain CH2 difference between individual representatives of the series, which is called a homological difference. It is a direct confirmation that the compound belongs to this organic series.
All aliphatic hydrocarbons are substances that are highly soluble in organic solvents.
Series isomerism
Representatives of a number of paraffins are characterized by isomerism of the carbon skeleton. It is explained by the possibility of spatial rotation of the carbon atom around chemical bonds. For example, for a compound with the composition C4H10, you can take a hydrocarbon with a straight carbon skeleton - butane. The structural isomer will be 2-methylpropane, which has a branched structure.
Among the typical chemical properties characteristic of paraffins, it should be noted that the saturation of bonds explains the complexity of the reaction and its radical mechanism. In order to obtain halogen derivatives of aliphatic hydrocarbons, it is necessary to carry out a halogenation reaction that occurs in the presence of UV radiation. The chain nature of this interaction is observed in all representatives of this series. The resulting products are called halogen derivatives. They are widely used in the chemical industry as organic solvents.
In addition, all aliphatic and aromatic hydrocarbons burn in the presence of oxygen, producing water and carbon dioxide. Depending on the percentage of carbon in the molecule, different amounts of heat are released. Regardless of the class of organic compounds, all combustion processes are exothermic reactions and are used in everyday life and industry.
Methane dehydrogenation (elimination of hydrogen) also has practical applications. As a result of this process, acetylene is formed, which is a valuable chemical raw material.
and chlorinated alkanes
Dichloromethane, chloroform, tetrachloromethane are excellent liquids. Chloroform and iodoform are used in modern medicine. The decomposition of methane is one of the industrial methods for producing soot necessary for the production of printing ink. Methane is considered the main source of hydrogen gas in the chemical industry, which is used for the production of ammonia, as well as for the synthesis of numerous organic substances.
Unsaturated hydrocarbons
Unsaturated aliphatic hydrocarbons are representatives of the ethylene and acetylene series. Let's analyze their main properties and applications. Alkenes are characterized by the presence of a double bond, so the general formula of the series is SpH2n.
Considering the unsaturated nature of these substances, it can be noted that they undergo hydrogenation, halogenation, hydration, and hydrohalogenation. In addition, representatives of the ethylene series are capable of polymerization. It is this feature that makes representatives of this class in demand in modern chemical production. Polyethylene and polypropylene are substances that form the basis of the polymer industry.
Acetylene is the first representative of a series with the general formula SpN2n-2. Among the distinctive features of these compounds is the presence of a triple bond. Its presence explains the reactions of the compound with halogens, water, hydrogen halides, and hydrogen. If the triple bond in such compounds is located in the first position, then alkynes are characterized by a qualitative substitution reaction with a complex silver salt. It is this ability that is a qualitative reaction to alkyne and is used to detect it in a mixture with an alkene and an alkane.
Aromatic hydrocarbons are cyclic unsaturated compounds and are therefore not considered aliphatic compounds.
Conclusion
Despite the differences in quantitative composition that exist between representatives of saturated and unsaturated aliphatic compounds, they are similar in quality, containing carbon and hydrogen in their molecules. Differences in the quantitative composition (different general formulas) between representatives of saturated and unsaturated CxHy explain the difference in the reaction mechanisms for obtaining various products.
That is why representatives of all classes of such compounds enter into combustion reactions, forming carbon dioxide, water, releasing a certain amount of thermal energy, which makes them in demand as fuel in everyday life and industry.
