Technical Bulletin:Update Water Elimination in Diesel Fuel

Technical Bulletin: Update Water Elimination in Diesel Fuel

Peter M Guerra - VP Technology


Lately there has been an exceptional amount of discussion about the best way to eliminate water from diesel fuel bulk and vehicle tanks. Since fuel injection technology is changing, there are concerns about some of the more traditional ways of handling water in fuel systems.

Recently some vehicle manufacturers have even released bulletins discouraging the use of fuel additives that emulsify water in fuel. I wanted to clearify this matter and assure you and your customers, FPPF products can be used with all the latest fuel injection technologies. Further, FPPF products provide the best solution to water in diesel fuel and gasoline. This is so important, since water remains the number one problem in fuel today.


Basic Definitions / General Problem Solving 

First chemical mixtures like Diesel Fuel, Gasoline and other fuels are hygroscopic or they attract water in all forms. The opposite of hygroscopic is hydrophobic or water repelling chemicals. These chemicals cause water demulsification.

Since fuels, despite their nonpolar characteristics attract water, this poses a major problem for all fuel consumers.

To eliminate water, you can emulsify “or better” completely encapsulate the water and subsequently pass the water through the fuel system in a safe way. The water actually gets vaporized and is harmlessly expelled through the exhaust system. The size of the created molecules are so small they are nanoscale and don’t harm or effect even the newest common rail fuel systems.

The other theoretical method to remove water is by demulsifying it and subsequently mechanically removing it from the fuel tank.

Let me back up a bit and explain there are actually three forms of water in fuel. Dissolved, emulsified and heavy water.  Dissolved water can total up to one tenth of one percent in fuel and is not a major concern as compared to the other water forms. Emulsified water is water that is semi-bonded to the water through forced mechanical mixing, usually caused by  agitation. The last and most harmful form is free water. This collects in the bottom of tanks due to a higher specific gravity than the fuel and water’s natural tendency to bond with itself, rather than non-polar compounds and mixtures.


What a demulsifier does is change almost all water in a fuel tank to free water. Coincidentally, this is the most harmful form of water. It does this by separating and preventing the hydrogen polar bonding of water to the fuel.

Although most “demulsifying” agents do not work completely, they do contribute to increasing the amount of free water in a tank. (For a fuel additive to truly function as a “complete fuel demulsifier”, the treat ratio of additive to fuel would be economically prohibitive.) The theory behind the use of demulsifier additives is they facilitate the operation of water separators and water filters. This is true to some degree, but since they do not provide  complete demulsification, the end result is questionable. Further, water separators are still not present in most diesel vehicles on the road today. Next water separators must be maintained, serviced and replaced regularly. The overall effectiveness of these devices is questionable at best.

The worst situation occurs if one uses a demulsifier additive in a vehicle without a water separator.  This means all the water in the vehicle goes through the injectors in its most harmful form:     “FREE WATER”

The Details 

First water enters fuel in several ways, due to fuel hygroscopic properties. In addition to water already present after it leaves the refinery, moisture in the air and environment will enter the fuel. Further condensation, poor storage and fuel management techniques exacerbate the problem. This occurs with all types of (ULSD) diesel fuel including #2 Summer, #2 Winter, #1 Kero, Biodiesel and Biodiesel blends. Biodiesel fuel is inherently more hygroscopic than all Petro-diesel (regular #1 and #2) so even a blend of B5 can hold more water in all forms.

How do FPPF Fuel Power Based Products Solve the Problem? 

Fuel Power puts water in a safe form to be eliminated from your tank as you consume the fuel. It breaks up the water droplets and encapsulates the emulsified water on a molecular scale using surfactant and hydrogen polar bonding chemistry.

The individual water molecules first bond to Fuel Power which then bonds to the fuel itself. The chemical content of Fuel Power functions as a strong coupling agent (chemical industry class of compounds) to combine all three compounds together into a homogenous combustible mixture. The end result is the microscopic water molecules in the tank are now completely separated from each other and when passing through the fuel system they vaporize safely.

When used with a water separator, Fuel Power only further improves the desired result of water elimination. FPPF Fuel Power based products, when used in fuel containing water, provides 4 benefits:

  • It makes the water combustible so it is consumed.
  • It significantly lowers the freeze point of water to prevent ice formation.
  • The specific gravity of chemical bonded water/Fuel Power is significantly greater than the base of fuel enabling a proper functioning water separator to remove any remaining water not eliminated by the additive treatment. (Fuel Power will only remove a finite amount of water when extreme water quantities are present.
  • Fuel Power stabilizes the fuel.

General Advantages of Water Encapsulation Products: 

  • Eliminates free water
  • Reduces the possibility of injector damage from water
  • Reduces the possibility of bacterial growth in the fuel
  • Helps improve fuel mileage by eliminating the negative effects of water in the fuel and further acting as a combustion catalyst.

Demulsifier Use, The Final Conclusions 

Demulsifiers “in theory” separate all the water from the fuel and make it free water. Demulsifiers are a valid potential water removal solution if and only if, your water separator is functioning and well maintained. Since agitation and the amount of demulsifiers in fuel additives is not enough to guarantee that all water is removed in the separators, one must be cautious. One final important recommendation: Don’t use a demulsifier chemical in your fuel, unless you have a water separator or a physical way to periodically remove free water from your fuel tanks.


The fear of water contamination of diesel fuel and related fuels, remains the number one concern of fuel/fleet managers across the country. The vast majority of diesel additive products do nothing to change or eliminate water in fuel. The products that demulsify fuel should be used only in certain instances where mechanical water removal is practiced. Even when this is the case, demulsifiers could cause winter ice ups in fuel, as they are separating the water and causing potential ice formation.

Products that encapsulate the water are best. For on the road vehicle fuel tanks and any other application, where the fuel is subjected to mechanical vibration, or no mechanical method of water removal exists, demulsifiers are potentially very harmful.

The best fuel additive to eliminate water should provide the following features:

  • Water encapsulation by hydrogen polar bonding
  • Lubricity improvers since water does reduce fuel lubricity.
  • Anti-icing chemistry to prevent ice ups in the winter.
  • Fuel stabilizing to prevent the aging of fel caused by the presence of water.
  • Combustion catalyst to maximize complete ignition of the fuel mixture.
  • Injector cleaner to insure maintenance of a clean fuel system.

All of the aforementioned features are provided by FPPF Fuel Power and Fuel Power containing products. If you have any questions please contact us at: 1-800-735-3773, or find us on Facebook.