Fuel System for Improved Fuel Efficiency Utilizing Glycols in a Spark Ignition Engine

Abstract

A fuel system for improved fuel efficiency which can be contained in a single fuel source, such as a fuel tank of a vehicle, having a gasoline phase comprises gasoline or gasohol; and an anti-knock phase comprising a glycol anti-knock subagent, water and one or more of a second anti-knock subagent selected from the group of methanol, ethanol and mixtures thereof; such that the anti-knock agent phase is substantially immiscible with the gasoline phase.

1 . A fuel system comprising:
 (a) gasoline phase comprises gasoline or gasohol; and   (b) an anti-knock phase comprising an anti-knock agent comprising a glycol anti-knock subagent, water and one or more of a second anti-knock subagent selected from the group of methanol, ethanol and mixtures thereof;   
     wherein the anti-knock agent phase is substantially immiscible with the gasoline phase. 
   
   
       2 . The system of  claim 1  wherein the glycol anti-knock subagent is selected such that the ratio of oxygen atoms present in the molecule and carbon atoms present in the molecule is from 0.4 to 1.0. 
   
   
       3 . The system of  claim 1  wherein the glycol anti-knock subagent is selected from the group consisting of glycerol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, isobutylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, C 5  diols and mixtures thereof. 
   
   
       4 . The system of  claim 1  wherein the glycol anti-knock subagent is selected from glycerol, 1,2-propylene glycol, 1,3-propylene glycol and mixtures thereof. 
   
   
       5 . The system of  claim 1  wherein the anti-knock subagent comprises less than 40% by volume of glycol anti-knock agent by volume of the anti-knock agent, preferably comprising from about 5% by volume to about 40% by volume of glycol anti-knock agent by volume of the anti-knock agent. 
   
   
       6 . The system of  claim 1  wherein the second anti-knock subagent is selected as water comprising at least 10% by volume of the anti-knock agent, preferably from about 10% by volume to about 40% by volume of the anti-knock agent. 
   
   
       7 . The system of  claim 1  wherein the second anti-knock subagent is selected as ethanol. 
   
   
       8 . The system of  claim 1  wherein the anti-knock agent comprises glycerol, water and ethanol, preferably water comprising at least 10% by volume of the anti-knock agent, preferably water comprising from about 10% by volume to about 40% by volume of the anti-knock agent. 
   
   
       9 . The system of  claim 1  wherein the anti-knock agent comprises 1,2-propylene glycol, 1,3-propylene glycol and mixtures thereof, water and ethanol, preferably water comprising at least 10% by volume of the anti-knock agent, preferably water comprising from about 10% by volume to about 40% by volume of the anti-knock agent. 
   
   
       10 . The system of  claim 1  wherein the anti-knock agent comprises glycerol, 1,2-propylene glycol, and mixtures thereof, water and ethanol. 
   
   
       11 . The system of  claim 1  wherein the glycol anti-knock subagent is selected from glycols of natural origin, preferably glycols derived from hydrolysis of fats and oils, made by fermentation of carbohydrates to give a naturally derived glycol or by partial hydrogenation of glycols of natural origin. 
   
   
       12 . The system of  claim 1  wherein the glycol anti-knock subagent is selected from glycol of petrochemical origin, preferably by the oxidation and hydration of olefins to give a petrochemical glycol. 
   
   
       13 . The system of  claim 1  wherein the anti-knock agent phase is dispensed into the single fuel source independently of the gasoline phase. 
   
   
       14 . The system of  claim 1  wherein the anti-knock agent phase and the gasoline phase are dispensed into a single fuel source in a vehicle at the same time. 
   
   
       15 . The system of  claim 1  wherein the anti-knock agent phase is injected into an engine cylinder independent of the gasoline phase. 
   
   
       16 . The system of  claim 1  wherein the anti-knock agent phase is injected into an engine cylinder after injection of the gasoline phase into an engine cylinder. 
   
   
       17 . The system of  claim 1  wherein the anti-knock agent is injected into an engine cylinder at about 280 to about 330 degrees crank angle.