Additive compositions for LPG fuel

• US 5,782,936 A
• Filed: 04/23/1997
• Issued: 07/21/1998
• Est. Priority Date: 04/23/1997
• Status: Expired due to Term

• Current Assignee: Suburban Propane Company
• Original Assignee: Suburban Propane LP (Suburban Propane Partners LP)
• Inventors: Riley, Richard A.
• Primary Examiner(s): Howard, Jacqueline V.
• Assistant Examiner(s): Toomer, Cephia D.
• Application Number:
  US08/842,390
• Time in Patent Office: 454 Days
• Field of Search: 44/300, 44/450, 44/451, 44/443, 585/14, 510/413
• US Class Current: 44/300
• CPC Class Codes: C10L 3/12 Liquefied petroleum gas liquefying by pressure and cold treatment F25J

Abstract

Additives for LPG fuels which reduce fouling, thereby increasing fuel efficiency while reducing particulates and carbon monoxide emissions, are provided. The additive compositions are produced from commonly available low cost products and comprise about 97.3 to 99.4 volume percent of a petroleum hydrocarbon which is a mixture of middle petroleum distillates and petroleum naphtha, about 0.3 to 1.5 volume percent of methanol and 0.3 to 1.2 volume percent ethoxylated alkylphenol. Optional components, such as upper cylinder lubricants, odorants and antiwear agents, may also be included in the additive composition.

Claims

1. An additive composition for LPG fuel comprising:

(A) about 97.3 to 99.4 volume percent of a petroleum hydrocarbon composition having an initial boiling point of at least about 170°

C. and a final boiling point of not greater than about 300°

C., said petroleum hydrocarbon composition comprising a mixture of middle petroleum distillates and petroleum naphtha at a volume ratio of 2;

1 to 10;

1;

(B) about 0.3 to 1.5 volume percent of methanol; and

(C) about 0.3 to 1.2 volume percent of an ethoxylated alkylphenol.

2. The additive composition of claim 1 wherein the petroleum hydrocarbon composition is present in the additive composition in an amount of 97.8 to 98.5 volume percent.

3. The additive composition of claim 1 wherein the volume ratio of middle petroleum distillates to petroleum naphtha is in the range of 3:

1 to 7;

1.

4. The additive composition of claim 3 wherein the volume ratio of middle petroleum distillates to petroleum naphtha is in the range of 4:

1 to 5.5;

1.

5. The additive composition of claim 1 wherein the methanol is present in the additive composition in an amount of 0.5 to 1.25 volume percent.

6. The additive composition of claim 1 wherein the ethoxylated alkylphenol is present in the additive composition in an amount of 0.5 to 1.0 volume percent.

7. The additive composition of claim 1 wherein the ethoxylated alkylphenol is prepared by the condensation of 6 to 20 moles of ethylene oxide with the alkylphenol.

8. The additive composition of claim 7 wherein the ethoxylated alkylphenol comprises ethoxylated nonylphenol.

9. The additive composition of claim 7 wherein the ethoxylated alkylphenol comprises ethoxylated octylphenol.

10. The additive composition of claim 1 further comprising a thiol odorant.

11. The additive composition of claim 1 further comprising a zinc dialkyldithiophosphate anti-wear agent.

12. The additive composition of claim 1 further comprising an upper cylinder lubricant.

13. An LPG fuel composition containing 100 to 5000 ppm of an additive composition comprising:

(A) about 97.3 to 99.4 volume percent of a petroleum hydrocarbon composition having an initial boiling point of at least about 170°

C. and a final boiling point of not greater than about 300°

C., said petroleum hydrocarbon composition comprising a mixture of middle petroleum distillates and petroleum naphtha at a volume ratio of 2;

1 to 10;

1;

(B) about 0.3 to 1.5 volume percent of methanol; and

(C) about 0.3 to 1.2 volume percent of an ethoxylated alkylphenol.

14. The LPG fuel composition of claim 13 wherein the petroleum hydrocarbon composition is present in the additive composition in an amount of 97.8 to 98.5 volume percent.

15. The LPG fuel composition of claim 14 wherein the volume ratio of middle petroleum distillates to petroleum naphtha is in the range of 3:

1 to 7;

1.

16. The LPG fuel composition of claim 15 wherein the volume ratio of middle petroleum distillates to petroleum naphtha is in the range of 4:

1 to 5.5;

1.

17. The LPG fuel composition of claim 13 wherein the methanol is present in the additive composition in an amount of 0.5 to 1.25 volume percent.

18. The LPG fuel composition of claim 13 wherein the ethoxylated alkylphenol is present in the additive composition in an amount of 0.5 to 1.0 volume percent.

19. The LPG fuel composition of claim 13 wherein the ethoxylated alkylphenol is prepared by the condensation of 6 to 20 moles of ethylene oxide with the alkylphenol.

20. The LPG fuel composition of claim 19 wherein the ethoxylated alkylphenol comprises ethoxylated nonylphenol.

21. The LPG fuel composition of claim 19 wherein the ethoxylated alkylphenol comprises ethoxylated octylphenol.

22. The LPG fuel composition of claim 13 further comprising a thiol odorant.

23. The LPG fuel composition of claim 13 further comprising a zinc dialkyldithiophosphate anti-wear agent.

24. The LPG fuel composition of claim 13 further comprising an upper cylinder lubricant.