Petroleum solvents (nefrases) are used in various industries for the dissolution and extraction of organic compounds. The main volume of solvents is used for the needs of the rubber, paint, and wood chemical industries, as well as for washing and degreasing metal surfaces.
Petroleum solvents include various fractions of oil obtained as a result of distillation. Nephras are divided into solvents with a low boiling point (gasoline), which boil at a temperature up to 150 °C (they are marked with the B index), and high (kerosene) solvents that boil at a temperature above 150 °C (they are marked with an index K). Depending on the hydrocarbon composition of the solvent, raw materials and production technology, petroleum solvents are divided into the following groups:
P – paraffinic, more than 50% (mass fraction) of normal paraffinic hydrocarbons;
And – isoparaffin containing more than 50% (mass fraction) of isoparaffin hydrocarbons;
H – naphthenic, containing more than 50% (mass fraction) of naphthenic hydrocarbons;
A – aromatic, containing more than 50% (mass fraction) of aromatic hydrocarbons;
C – mixed, containing no more than 50% (mass fraction) of hydrocarbons of each of the groups
According to the content of aromatic hydrocarbons (% by mass), groups P, I, H and C are divided into subgroups:
0 – less than 0.1;
1 – 0.1-0.5;
2 – 0.5-2.5;
3 – 2.5-5.0;
4 – 5-25;
5 – 25-50.
Marking of petroleum solvents (nefras) includes group designation, subgroup number, lower and upper boiling limits of the product. For example, paraffin oil solvent containing 2.5-5.0% aromatics. hydrocarbons and boils in the range of 30-80 ° C, denoted: nefras-PZ-30/80.
The table shows the designations and names of some petroleum solvents.
Names of petroleum solvents
Marking
Gasoline-solvent for the rubber industry Nefras S2-80/120
Nefras C3-80/120
Solvent for technical purposes Nefras S-50/170
Gasoline-solvent for the paint industry (white spirit) Nefras S4-155/200
Solvent petroleum Nefras A-130/150
Heavy petroleum solvent Nefras A-120/200
Nefras C3-70/95 straight-run extraction gasoline
gasoline extraction Nefras S2-70/85
Gasoline-solvent for the forestry industry Nefras S3-105/130
Petroleum ether fraction Nefras P4-30/80
Heptane solvent Nefras C3-94/99
Nefras C4-150/200 white spirit substitute
Hexane solvent Nefras P1-65/75
Nefras P1-63/75
Nefras P1-65/70
Technological solvent for the “Alfol” Nefras H2-220/300 process
Solvent for household insecticides Nefras I2-190/320
Petroleum aromatic solvent Nefras A-150/330