US2244496A

US2244496A - Fuel for compression ignition engines

Info

Publication number: US2244496A
Application number: US211208A
Authority: US
Inventors: Ernest M Marks
Original assignee: Atlantic Refining Co
Current assignee: Atlantic Richfield Co
Priority date: 1938-06-01
Filing date: 1938-06-01
Publication date: 1941-06-03
Anticipated expiration: 1958-06-03

Description

Patented June 3, 1941 FUEL FOR COMPRESSION IGNITION EN GIN Ernest M. Marks, Lansdowne, Pa., assignor to The Atlantic Refining Company,

Philadelphia, Pa.,

a corporation of Pennsylvania No Drawing. Application June 1, 1938, Serial No. 211,208

2 Claims.

The present invention relates to improvements in compression ignition'fuels, and relates more.

particularly to the use of nitrosites and/or nitrosates as ignition accelerators for hydrocarbon fuels of the compression ignition type.

A principal object of this invention is the improvement of Diesel engine fuels, and particularly of fuels adapted for use in high-speed compression ignition engines, whereby there is obtained a reduction in the ignition temperature of the fuel oil and a reduction of the delay period between the injection and ignition of the fuel oil.

In accordance with this invention improved compression ignition fuels may be obtained by reacting olefine hydrocarbons or hydrocarbon mixtures containing olefines with an oxide of nitrogen, particularly nitrogen trioxide or nitrogen tetroxide, to form nitrosites or nitrosates, respectively, and thereafter adding the nitrosite or nitrosate to fuel oil in an amount suflicient to substantially increase the cetane number of the fuel oil. Or, fuel oil containing olefines may be treated directly with the aforesaid oxides of nitrogen, thereby producing from the unsaturated oil components, nitrosites or nitrosates which remain in solution in the fuel oil. Such treated fuel oil may be employed directly as a compression ignition fuel, or may be diluted to the desired extent with untreated fuel oil. In either case a fuel of improved cetane number is obtained, the increased cetane number being reflected in a lowering of the ignition temperature of the fuel oil and in a reduction in the delay period between injection and ignition of the fuel.

Among the hydrocarbons or hydrocarbon mixtures which may be employed in the preparation of nitrosites and/or nitrosates are included olefines, preferably such aspropylene, butylene, isobutylene, di i'sobutylene, tri isobutylene, amylene, di amylene, methyl pentene, methyl hexene, ethyl hexene, dimethyl octene, decene, dodecene, pinene, and the like. Various hydrocarbon mixtures containing olefines which may be utilized are kerosine, gas oils, and particularly cracked J1 recycle gas oils boiling substantially within the range of from about 400 F. to about 750 F. Unsaturated kerosine, gas oil or'higher boiling )i1 fractionsproduced bysolvent extraction with ;elective solvents suchas liquefied sulfur dioxide, ahenol, furfural, chlorex, aniline, ,nitrobenzene Jr cresylic acid m y likewise be suitably em- )loyed. 1

The following examples are illustrative of the 'esults which-may be obtained in the practice of he present invention. The cetane number of he fuel is employed herein as an index of the ualityof the fuel, and an improvement in the uel is expressed by an increase in the cetane lumber. a I

(1) 3540 parts by weight of a gas oil resulting over anhydrous (N203) generated by weight of AS203.

period being about 2 hours.

from the production of gasoline by cracking a high boiling petroleum oil and having a boiling range of 281 F. to 605 R, an Al P. I. gravity of 28.3, and an aniline number of 86 was treated with nitrogen. tetroxide (N02) generated by the action of 500 parts by weight of concentrated HN03 upon 150 parts by weight of NaN02. The treatment was carried on at a temperature of about 50 F., the reaction period being about 2 hours. The treated gas oil containing nitrosates resulting from the reaction of the N02 upon unsaturated components of the oil, was thoroughly washed with water to remove unreacted N02. The washed oil was then dried over anhydrous CaCl2 and tested for increase in cetane number. The cetane number of the untreated gas oil was found to be 28, whereas the cetane number of the treated gas oil containing nitrosates was found to be 42.

(2) 3200 parts by boiling range of 220 gravity of 34.8" was treated with nitrogen tetroxide (N02) generated by the action of 500 parts by weight of concentrated HNOs upon 150 parts by weight of NaN02. The treatment was carried on at a temperature of about 50 F., the reaction period being about 2 hours. The treated gas oil containing nitrosates resulting from the reaction of the N02 upon unsaturated components of the oil, was thoroughly washed with water to remove unreacted N02. The washed oil was thendried CaCl2 and tested for increase in cetane number. The cetane number of the untreated gas oil' was found to be 37, whereas the cetane number of the treated gas oil containing nitrosates was found to be 56.

(3) 450 parts by weight of the gas oil used in Example 1 was treated with nitrogen trioxide the action of 500 parts by weight of concentrated HNO; upon parts by The treatment was carried out of about 80 F., the reaction The treated .gas oil containing nitrosites resulting from. the reaction of the N203 upon unsaturatedycomponents of the oil was thoroughly washed with water to removeunreacted N202 and then dried over anhydrous CaCla, 5 parts by volume of the treated oil was admixed with parts by volume of gas oil having a. boiling range of 390 F. to 672 R, an A. P. I. gravity M302", and an aniline number of 157. The cetane number of the unblended gas oil was found to be 49, whereas the cetanc number of the blended fuel containing 5% of treated oil was found to be 55.

(4) 225 parts by weight of the gas oil used in Example 1 was diluted with 450 parts by weight of diethyl ether and treated with nitrogen tetroxide (N02) generated by the action 'oflhOO weight of gas oil having a F. to 614 R, an A. P. I.

at a. temperature and an aniline number of 124 parts by weight of concentrated HNO; upon 170 parts by weight of NaNO2. The treatment was carried out at a temperature of about 32 F., the reaction period being about 1 hours. The ether solution of the treated gas oil containing nitrosites resulting from the reaction of the N02 upon unsaturated components of the oil was thoroughly washed with water to remove unreacted N02, the solution then dried, and the ether removed by vaporization. 5 parts by volume of the treated oil was admixed with 95 parts by volume of gas oil having a boiling range of 390 F. to 672 R, an A. P. I. gravity of 302, and an aniline number of 157. The cetane number of the unblended gas oil was found to be 49, whereas the cetane number of the blended fuel containing 5% of treated oil was found to be 53.

(5) 225 parts by weight of gas oil having a boiling range of 220' F. to 614 R, an A. P. I. gravity of 34.8", and an aniline number of 124 was diluted with 450 parts by weight of diethyl ether and treated with nitrogen trioxide (N203) generated by the action of 500 parts by weight of concentrated HNOs upon 75 parts by weight of AS203. The treatment was carried out at a temperature of about 32 F., the reaction period being about 2 hours. The ether solution of the treated gas oil containing nitrosites resulting from the reaction of the N203 upon unsaturated components of the oil was thoroughly washed with water to remove unreacted N203, the solution then dried, and the ether removed by vaporization. 5 parts by volume of the treated oil was admixed with 95 parts by volume of gas oil having a boiling range of 390 F. to 672 F., an A. P. I. gravity of 30.2", and an aniline number of 157. The cetane number of the unblended gas oil was found to be 49. whereas the cetane number of the blended fuel containing 5% of treated oil was found to be 55.

(6) 225 parts by weight of gas oil used in Example 5 was diluted with 450 parts by weight of diethyl ether and treated with nitrogen tetroxide (N02) generated by the action of 500 parts by weight of concentrated HNOs upon 170 parts by weight of NaNO::. The treatment was carried out at a temperature of about 32 F., the reaction period being about 1 /2 hours. The ether solution of the treated gas oil containing nitrosites resulting from the reaction of the N02 upon unsaturated components of the oil was throughly washed with water to remove unreacted N02, the solution then dried, and the ether removed by vaporization. 5 parts by volume of the treated oil was admixed with 95 parts by volume of gas oil having a boiling range of 390 F. to 672 R, an A. P. I. gravity of 30.2", and an aniline number of 157. The cetane number of the unblended gas oil was found to be 49, whereas the cetane number of the blended fuel containing 5% of treated oil was found to be 53.

(7) 100 parts by weight of commercial diamylene having a boiling range of 302 F. to 338 F., and an A. P. I. gravity of 51.5 was diluted with 300 parts by weight of diethyl ether and treated with nitrogen trioxide (N203) generated by the action of 450 parts by weight of concentrated HNO3 upon 50 parts by weight of AS203. The treatment was carried out at a temperature of about 50 F.. the reaction period being about 2 hours. The ether solution of diamylene nitrosite resulting from the reaction of the N202 upon the diamylene was thoroughly washed with water to remove unreacted N203, the solution then dried, and the ether removed by vaporization. 3 parts by volume of the diamylene nitrosite was admixed with 97 parts by volume of a Diesel reference fuel consisting of 60% by volume of straight-run, parafiinic gas oil and 40% by volume of a-methyl naphthalene. The cetane number of the reference fuel was found to be 44, whereas the cetane number of the blended fuel containing 3% of diamylene nitrosite was found to be 54.

(8) 100 parts by weight of commercial diamylene used in Example 7 was diluted with 300 parts by weight of diethyl ether and treated with nitrogen tetroxide (N02) generated by the action of 400 parts by Weight of concentrated HNO3 upon parts by weight of NaNO2. The treatment was carried out at a temperature of about 50 F., the reaction period being about 2 hours. The ether solution of diamylene nitrosate resulting from the reaction of the N02 upon the diamylene was thoroughly washed with water to remove unreacted N02, the solution then dried, and the ether removed by vaporization. 3 parts by volume of the diamylene nitrosate was admixed with 97 parts by volume of 9. Diesel reference fuel consisting of 60% by volume of straight-run, parafiinic gas oil and 40% by volume of a-methyl naphthalene. The cetane number of the reference fuel was found to be 44, whereas the cetane number of the blended fuel containing 3% of diamylene nitrosate was found to be 55.

It will be seen, from the above examples, that a marked improvement in the cetane number of compression ignition fuels is obtained by the addition thereto or the formation therein of, nitrosites and/or nitrosates of unsaturated hydrocarbons.

Among the advantages which accrue from the use of nitrosites and/or-nitrosates as ignition accelerators in compression ignition fuels may be mentioned:

(1) Elimination of knocking and rough-running by decreasing the ignition lag.

(2) Easier starting due to the reduced spontaneous ignition temperatures of the blended fuel.

(3) Possibility of using inferior grade of fuel oil. By the addition of the accelerator, low grade fuels which at present are unsuitable for use in compression ignition engines, may be rendered equal or superior to high grade unblended fuels.

The above description and examples are to be taken as illustrative only and not as limiting the scope of'the invention. Any modification or variation therefrom which conforms to the spirit of the invention is intended to be included within the scope of the claims.

In the appended claims the term gasoline boiling range refers to a temperature range of the order of about 90 F. to 390 F.

. What I claim is:

1. A compression ignition fuel comprising fuel oil boiling above the gasoline boiling range and a compound from the group consisting of diamylene nitrosite and diamylene nitrosate, said compound being present in an amount sufficient to substantially increase the cetane number of the fuel oil.

2. A compression ignition fuel comprising fuel oil boiling from about 400 F. to about 750 F. and a compound from the group consisting of diamylene nitrosite and diamylene nitrosate, said compound being present in an amount suflicient to substantially increase the cetane number of the fuel oil.

ERNEST M. MARKS.