US2984552A

US2984552A - Leaded gasoline containing phosphorus

Info

Publication number: US2984552A
Application number: US697318A
Authority: US
Inventors: Everett N Case
Original assignee: Sinclair Refining Co
Current assignee: Sinclair Refining Co
Priority date: 1957-11-19
Filing date: 1957-11-19
Publication date: 1961-05-16
Anticipated expiration: 1978-05-16
Also published as: DE1081272B; GB866414A

Description

United States Patent 2,984,552 LEADED GASOLINE CONTAINER} PHOSPHORUS Everett N. Case, Homewood, 11L, assignor to Sinclair Refining Company, New York, N.Y., a corporation of Maine No Drawing. Filed Nov. 19, 1957, Ser. No. 697,318 2 Claims. (Cl. 44-69) My invention relates to improved gasoline which is of high octane number and which contains tetraethyl lead as an anti-knocking agent.

By and large, modern gasolines for use in spark-ignited internal combustion engines have an octane number of at least 85 RON, that is, as determined by the Research Method, and they contain tetraethyl lead, generally within the range from 0.5 to 3.0 cc. per gallon, or even as much as approximately 4.5 cc. per gallon, as a knock-suppressing agent. Tetraethyl lead is the most widely used antiknock agent, and is very effective for this purpose, but it sutfers from the defect that it causes lead-containing deposits in the cylinders. These deposits have a tendency to cause preignition; that is, the deposits are hot and cause the mixture in the cylinder to burn before combustion is initiated at the proper time by the spark plug. Preignition can be controlled, as the art is aware, by the addition of phosphorus additives to leaded gasoline. However, the phosphorus additive must be properly chosen or otherwise when the engine is put into service and operated, the octane requirement increase .encountered as the engine cylinders build up deposits will be greater than that which takes place when no phosphorus additive is used.

In accordance with my invention, yellow phosphorus (sometimes known as white phosphorus or alpha-white phosphorus) is incorporated into leaded gasoline with the result that preignition is suppressed and the octane requirement increase as the engine is used is less than that encountered with the base fuel, that is, the gasoline not containing any phosphorus additive. The yellow phosphorus is incorporated into the gasoline generally in the amount of from 0.1 to 2 theory, and preferably in the amount of from 0.2 to 0.6 theory, 1.0 theory meaning that for each three gram atoms of lead present in the tetraethyl lead there are present two gram atoms of yellow phosphorus. One theory is based upon the premise that the phosphorus and the lead in the tetraethyl lead react in the combustion zone to form lead orthophosphate, Pb (PO Stated somewhat differently, for each three gram moles of tetraethyl lead present in the gasoline, there is also generally present from 0.2 to 4 gram atoms of yellow phosphorus and preferably from 0.4 to 1.2 gram atoms of yellow phosphorus.

Example ASTM distillation of the gasoline was as follows:

F. Initial boiling point 115 percent 210 50 percent 324 90 percent 357 End poin 421 fiice Into a portion of the base gasoline there was dissolved 0.3 theory of yellow phosphorus, this amount being 0.0936 gram of yellow phosphorus per gallon of base gasoline. When the base gasoline and the base gasoline containing the yellow phosphorus were subjected to comparative tests in a spark-ignited single cylinder combustion engine, it was found that the gasoline containing the yellow phosphorus showed a ping count per hour of 157 and that the base gasoline showed a ping count per hour of 333.

A second sample of base fuel was obtained, this particular sample being composed of a mixture of alkylate, heavy reformate from straight run naphtha, light fluid cracked gasoline and butane. This particular gasoline contained 3 cc. per gallon of tetraethyl lead together with the usual scavengers, had an API gravity of 53.6, an octane number by the Research Method of 101.4 and an octane number by the Motor Method of 91.4. The ASTM boiling range of the second base gasoline was as follows:

F. Initial boiling point 5 percent 118 50 percent 264 90 percent 319 End point 381 Into a portion of the second base gasoline there was dissolved yellow phosphorus in the amount of 0.3 theory. The second base gasoline and a portion thereof containing the yellow phosphorus were then tested in a 1957 model automobile engine for octane requirement increase, with the results shown in the table below:

Engine octane requirement 1. Gasoline containing from 0.5 to 4.5 cc. per gallon of tetraethyl lead and also containing yellow phosphorus in the amount of from 0.1 to 2 theory.

2. Gasoline containing from 0.5 to 4.5 cc. per gallon of tetraethyl lead and also containing yellow phosphorus in the amount of 0.2 to 0.6 theory.

References Cited in the file of this patent UNITED STATES PATENTS 1,913,970 Albers June 13, 1933 2,405,560 Campbell Aug. 13, 1946 2,563,101 Colwell et a1 Aug. 7, 1951 2,794,717 Gilbert June 4, 1957 2,797,153 Bereslavsky June 25, 1957 FOREIGN PATENTS 709,653 Great Britain June 2, 1954 1,094,828 France May 24, 1955 1,123,123 France Sept. 18, 1956 OTHER REFERENCES Petroleum Refining With Chemicals," by Kalichevsky et aL, Elsevier Publishing Co., 1956, p. 491.

Claims

1. GASOLINE CONTAINING FROM 0.5 TO 4.5 CC. PER GALLON OF TETRAETHYL LEAD AND ALSO CONTAINING YELLOW PHOSPHORUS IN THE AMOUNT OF FROM 0.1 TO 2 THEORY.