Solvent, Petroleum

Solvent, Petroleum 

any individual or mixed liquid hydrocarbon obtained from petroleum and used as a solvent in commercial production and laboratory research.

Petroleum solvents readily dissolve all petroleum fractions, vegetable oils and fats, and organic compounds of sulfur, oxygen, and nitrogen. The solvent action increases with the solvent’s aromatic-hydrocarbon content. All petroleum solvents poorly dissolve water (hundredths of a percent). Aromatic solvents poorly dissolve solid paraffins, while liquid propane poorly dissolves asphaltic resinous substances. Petroleum solvents (benzene, toluene, and xylene) exhibit low toxicity and are explosive.

Liquid propane is used to deasphalt tar. Pentane, hexane, heptane, and octane are used in laboratory work. Benzene, toluene, and commercial xylene are used in the manufacture of plastics, resins, varnishes, dyes, and mastics. Gasoline is a solvent used by the rubber industry in the preparation of rubber cement, special quick-drying oil varnishes, and dyes. Petroleum spirits are utilized in the paint and varnish industry and in the preparation of drying oils to dissolve oil enamels, bituminous varnishes, and electrical insulating varnishes.

Extraction gasoline removes oils from seeds and oil cakes, fat from bones, and nicotine from Indian tobacco leaves. Gasoline is used in the manufacture of artificial leather: it is also used to chemically clean fabrics, rinse parts during repair work, and remove anticorrosive coatings.

The basic characteristics of petroleum solvents are listed in Table 1.

Table 1. Basic characteristics of petroleum solvents*
	Density at 20°C(g/cm3)	Fractional composition		Sulfur content (percent)
		Start of boiling (°C)	End of boiling (°C)
*Solvents should not contain hydrogen sulfide, mercaptans, acids, alkalies, water, or mechanical impurities. Aromatic hydrocarbon content in petroleum ether grades 40–70 and 70–100 should not exceed 3%, in extraction gasoline it should not exceed 4%, and in petroleum spirit it should not exceed 16%. Petroleum toluene should contain at least 95% sulfonating compounds †10% is boiled off at temperatures no lower than those given * *95% is boiled off at temperatures no higher than those given
Petroleum benzene...........	≤0.875–0.88	≥79–79.6	≤80.4–80.6	≤0.0002
Petroleum toluene.............	≤0.856–0.866	≥109	≤111.2	–
Commercial xylene..............	≤0.86–0.866	≥136.5	≤141.5	–
Petroleum ether
Grades 40–70.................	≤0.65	≥36†	≤70**	none
Grades 70–100.............	≤0.695	≥70†	≤100**	none
Gasoline-solvent in rubber industry
BR-1 (Galosha).............	≤0.730	≥80	≤120	–
BR-2............	≤0.730	≥80	≤120	≤0.025
Petroleum spirit............	≤0.795	≥165	≤200	≤0.025
Extraction gasoline............	≤0.725	≥70	≤95	≤0.025
Gasoline for commercial andtechnical use.................	–	≥45	≤170	≤0.025

REFERENCES

Tovarnye nefteprodukty, ikh svoistva i primenenie: Spravochnik. Edited by N. G. Puchkov. Moscow, 1971.
Nefteprodukty. Moscow, 1970.
Papok, K. K., and N. A. Ragozin. Tekhnicheskii slovar’-spravochnik po toplivu i maslam, 3rd ed. Moscow, 1963.