PIB as a fuel additive

[SVOboy]

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=
PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=5906665.WKU.&OS
=PN/5906665&RS=PN/5906665

"Without being limited to any particular theory of operation, the effectiveness of the present invention is believed to be related to a suppression in the formation of sub-50-micron diameter droplets as the fuel is sprayed. In addition, based on the present understanding of the invention, the additive of the present invention increases the momentary, or extensional, viscosity of the fuel droplets under conditions such as those encountered in engine fuel and combustion systems. Other physical properties of the fuel are also believed to be affected, including the surface tension and relative rigidity of the fuel droplets. A standard research octane number test showed an increase in octane number with a low concentration of high molecular weight polyisobutylene.

The modification of the physical properties of the fuel by adding high molecular weight polyisobutylene controls the rate at which fuel components vaporize. Fuel droplet size is more uniform. The polymeric additive of the present invention suppresses formation of very small droplets.

The momentary viscosity of spray droplets of fuel containing a low concentration of a very high molecular weight viscoelastic polymer is greatly increased over that of neat fuel. The changes in the fuel made by the additive, in particular, the physical properties of the fuel, result in reduced vaporization of the fuel during the intake stroke of the engine, and thereby increases the volumetric efficiency of 4- and 2-cycle ignition engines. A momentary increase of the viscosity of a fuel droplet also retards the fractional distillation of smaller fuel molecules, making the final fuel air mixture more homogeneous.

The extended polymer molecules can only relax by a thermal mechanism, over a millisecond duration period, which increases with molecular weight. This second transient effect of the high molecular weight polymer is especially significant where induction, vaporization, and combustion events are changing quickly with time, e.g., heavy load, rapid acceleration, and combinations of loading and acceleration. Very small concentrations of the additive are required.

The concentration of polymer in the fuel typically is 1 to 20 ppm. At these low concentrations, it is unlikely that the polymer could be involved in the process of combustion in a strict chemical, as distinguished from a purely physical-chemical, sense. It is known, however, that the polyisobutylene preferably used in this fuel additive is the most pure commercial grade of polyisobutylene available today. When heated in a vacuum at 200.degree. C., the cold trap fills with pure, water-white isobutylene. The residue shows no evidence of charring; rather, the process resembles the sublimation of carbon dioxide. Although this may account for the non-fouling action of this particular polymer additive composition (the ideal drag reducer for product pipeline flow improvement), it is difficult to see how this property could improve combustion on its own.

The additive also prevents drying of injectors (when used with a light carrier distillate), and reduces flow resistance in the entire fuel system (drag reduction). It may also serve to lubricate parts in the fuel system, but these potential benefits are believed to be secondary to volumetric efficiency and combustion effects. "

"Sixteen grams of ultra high molecular weight polyisobutylene, coated with polyethylene wax (designated as Oppanol.RTM. B246 by the supplier BASF) was cut into approximately 1/8" pieces. The pieces were cut from the center of each PIB pellet to reduce the amount of polyethylene wax that would be carried into the initial solutions. The pieces of polymer were added to 800 grams of isooctane. The container containing the polymer and the solvent was stirred with a flat blade for 24 hours. The resulting solution (hereafter referred to as PIB stock solution) contained 2% polyisobutylene (Oppanol.RTM. B246). 800 grams of the PIB stock solution was then combined with 800 grams of Exxon 100 Solvent Neutral Oil to form a final additive blend of 50% PIB stock solution, and 50% Solvent Neutral Oil. The additive mix was then put into 2 ounce containers. The additive was added to the fuel tank of a 1980 Nissan 280ZX prior to filling the fuel tank at a service station. It was added at the rate of 2 ounces to 10 gallons of fuel. Gasoline was then added to the tank to promote mixing. The Nissan 280ZX showed immediate improved performance in both acceleration and engine smoothness and gave gasoline mileage improvement. "

"EXAMPLE 4

The same PIB base stock solution used in Example 3 was used in a Ford Cosworth racing car. The amount of fuel needed for the race was calculated and was added to the vehicle's fuel tank. The additive was added to the fuel tank at a rate of 2 ounces per 10 gallons of fuel. The vehicle ran the race at its maximum speed. At the end of the race the fuel tank was drained and 21/2 gallons of fuel were removed. The driver estimated an improvement in fuel consumption of more than 20%.

EXAMPLE 5

The same PIB base stock solution used in Example 3 was used in the tow truck that transported the race car in example #4. The fuel mileage was calculated on the original trip to the race track. Additive was added to the tow truck at a rate of 2 ounces per 10 gallons of fuel. On the return trip an increase in fuel mileage of more than 25% was recorded. "

Interesting stuff, I think this is the next big acetone in terms of fuel additives.

[SVOboy]

<a href=http://www.exxonmobilchemical.com/Public_Files/Butyl/Butyl_Polymers/Worldwide/Technical_Guide_Vistanex_PIB.pdf target=_blank>More links to exxon</a>

[diamondlarry]

I have some interesting results on my PIB tests. I only had 223.125 miles on the tank but thought I would top it off anyway. the reason for the three decimal places is that my speedo is off 5%(on the low side) so when I added 5% to my 212.5 on the odometer, it came to 223.125. I used 5.442 gallons for an mpg figure of 41.0 mpg. This is only a 5% increase so far, but it looks promising. I do know that we are now being "treated" to the wonderful winter blend in our area so it may take a little longer to get accurate results.

[diamondlarry]

I have some more results to report on my PIB testing. I went for a 40 mile trip today(40.48 corrected, 38.55 odometer). The route consisted of mostly highway and about 8-9 miles of rural county roads. My speed was 55 on the highway and 50 on the county portion. I used a total of .790 gallons for the trip for 51.24 mpg. I made a total of 6 stops during the trip. Since I was trying to check the calibration of my Scanguage, the little coasting I did was with the engine running while in neutral. The next time I make the run I'll do my coasting with the engine off. I believe I could get this figure to closer to 55 mpg by shutting off the engine while coasting. By the way, the above mileage figures were obtained by the refill and divide the mileage by gallons method.
Larry

[SVOboy]

Cool cool, what is that compared to your baseline mileage? After your next result start a thread in the experiments section about it, or I could, if you wish, but you'll know more, of course, keep it up, I'm waiting for my acetone results still.

[SVOboy]

<a href=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=5906665.WKU.&OS=PN/5906665&RS=PN/5906665>Patent info</a>

Very interesting indeed, this test is high up on my list, hopefully larry's results prove quite good.

[Matt Timion]

any more developments Larry? if you had to choose between PIB and acetone, which would you choose?

[diamondlarry]

With it being around the time of "winter blend" gas, it may take awhile to tell how well the PIB is working. If I had to make a choice right now I would probably choose the PIB. But, like I said, that could change with further testing of winter gas. For now, the reason I would choose PIB is cost. I paid $7.25/quart + shipping for my Torco 2-stroke oil. I used 6.5 ounces in a gallon of gas and use 1 ounce of that mixture/gallon of gas. At this rate it will take a LONG time to use up the oil.
PS: I forgot to say that I recently added some acetone and Coleman's fuel to my tank to test how PIB and those other things work together. Might be interesting.

[diamondlarry]

I was just made aware of an error in my calculations for using Torco oil. I will do some further checking to make sure I haven't messed up again but here is what I think the new amounts should be. 1.25 ounces of Torco oil in one gallon of gas then 1 ounce of that mixture/gallon of gas added to the fuel tank. This makes it even more economical than before. This means that one quart of oil will treat 3276.8 gallons of gas. This mixture results in a ppm count of around 25ppm.

[rh77]

After replacing the thermostat, PIB may be my next experiment. Any updates on the progress? I hear that John Deere makes an additive that contains good level of PIB...

RH77