AFC Series Diesel Fuel Additive is a Fuel Catalyst, Fuel Stabilizer
and Tank Cleaning Additive
-- A Technical Discussion --

The following begins a somewhat more technical discussion on the benefits of, and how AFC Series Diesel Fuel Additive, Catalyst, Fuel Stabilizer and Tank Cleaning Additives impact the diesel engine Combustion Process.  This article discussed how it handles Combustion Byproducts, Removes and Eliminates Combustion Deposits, Effects SOx, NOx, Low Sulfur Fuels, Fuels that contain Vanadium and Sulfur, and Pour Point & Cloud Point. You may wish to consider this optional information as it does provide a more in-depth view of the benefits of AFC.

How AFC Series Fuel Catalyst helps the Combustion Process

The AFC Series Fuel Catalyst interacts with the heavier, long chain, combustion resistant elements of the fuel, and existing carbon deposits. This interaction allows these deposits to break down and burn. The “molecular atomization” of the fuel, and the destruction and burning of the surface deposits produce the following positive effects on the combustion process:

  • Quicker, more complete combustion

  • Optimal use of available oxygen

  • Lower excess air requirements

  • Removal of existing deposits

  • Better heat transfer

  • Lower fuel consumption

  • Increased overall efficiency

How AFC Series Fuel Catalyst Effects Combustion Byproducts

AFC-705 enhances the combustion process, which leads to the following positive effects on combustion byproducts:

  • Inhibition of new deposit formation

  • Removal of old carbon deposits

  • Prevention of new deposit formation

  • Decreased fuel consumption

  • Decreased particulate, smoke and soot

  • Decreased NOx, SOx, CO, and VOC emissions

  • Decreased carbon content in the ash

  • Decreased fouling and corrosion due to decrease in V205 activity

  • Decreased cold-end corrosion due to decreased SO3 formation

These effects lead to a significant increase in energy output by burning a larger portion of the Carbon available in fuel, and an important reduction in corrosion due to much lower formation of SO3, which increases the amount of SO2, harmlessly captured in ash.

The Deposit Removal Mechanism

Combustion Deposits are mostly carbon and aromatic compounds in a highly combustion resistant state. These deposits are the source of many engine problems, such as higher than normal fuel consumption, excessive harmful exhaust, and costly maintenance. Fuel problems and incomplete combustion ultimately cause complete engine failure.

Deposit formation begins with spherical molecules called primary particles and branched aromatic chains, both of which are produced in the early stages of combustion. The chain branches consist of alkyl, alcohol, carbonyl and carboxyl compounds. The alkyls oxidize to alcohol, oxidizing to carbonyl, oxidizing to carboxyl. The oxidation process stops with the carboxyl compounds, which are acidic and highly combustion resistant with a high energy of activation.

The various branch compounds are attracted to the primary particles, which spin at extremely high velocities. When a branch becomes attached to a primary particle, the entire chain structure is quickly wrapped around the primary particle forming a secondary particle. These secondary particles agglomerate and form a tertiary particles. This can happen when several primary particles become attached to the same chain on different branches, and then simultaneously become secondary and tertiary particle, as they wrap up the chain.

Tertiary particles agglomerating on a surface will become further coated to form quaternary particle. The coated quaternary particles make up deposits. The chain structures coating the surface of deposits leave exposed branches. It is at these branches where AFC catalyst begins to break down and destroy the deposits as it modifies the surfaces.

The carboxyl branches are acidic, and attract the AFC catalyst oxide which is basic. When the two combine a process called dehydration occurs and a water molecule is produced. What remains is a compound with a low energy of activation, which readily breaks down at high temperatures, releasing a CO2 molecule and the catalyst oxide.

Upon releasing the CO2 and the catalyst oxide, the end of the chain re-oxidizes to an alkyl, alcohol or carbonyl compound and finally to a carboxyl compound. When the end of the chain reaches this state, the catalyst oxide once again combines with the carboxyl, and starts the break down cycle again. Over time, the deposits are removed by being converted to CO2 and water.

AFC inhibits the formation of new deposits in much the same way as it destroys existing deposits. It interacts with the ends of the aromatic chains and the attachment sites on the primary particles. This interaction keeps the primary particles from wrapping up full chains, by blocking or destroying the attachment sites, and/or breaking the chains.

This interference stops the deposit agglomeration process at the primary and/or secondary particle agglomeration state. This results in much lighter and smaller particles that don’t stick together and are more easily oxidized. The result of this interference is a lower mass of particulate emissions, and instead an increased energy output, and increased production of CO2 and water, which are the desirable end products of the combustion cycle.

Deposits are the major source of emissions. Eliminating deposits lowers the production of soot and smoke. The use of AFC enhances energy output and optimizes the production of CO2 and water during the entire combustion process, which significantly lowers the output of both regulated and unregulated emissions.

Eliminating Combustion Deposits

AFC Series technology is based on the catalytic effects of organo-metalics. The main active ingredients are synergistic, multi-functional combustion catalysts containing combustion surface modifiers and deposit surface modifiers. AFC can be used with any liquid hydrocarbon fuel such as gasoline, diesel, residual fuel and HFO.

In an AFC treated environment, the surfaces of the fuel particles and deposits are modified such that the catalyst lowers the energy of activation of the deposit surfaces. The modified surface deposits can then burn up at a much lower temperature.

A typical engine develops a temperature gradient ranging from 200 deg. C at the combustion chamber wall, to 1200 deg. C in the combustion center. Many of the fuel components require a higher temperature than 600 deg. C to combust. It is not possible to completely burn heavy fuel components in temperatures ranging from 200 deg. to 600 deg. C. Incomplete combustion forms the deposits, harmful emissions, and the consequential mechanical problems.

Combustion chamber deposit surfaces and fuel particles treated with AFC begin to combust at temperatures as low as 200 deg. C and then burn over the entire temperature range. This results in complete combustion and eventually in the total removal of all engine deposits, while at the same time preventing new deposit buildup. Complete combustion leads to better performance, lower fuel consumption, lower emissions (CO, SOx, NOx, HC’s and PM-10), lowering operating cost, maintenance and downtime.

The process of deposit removal begins immediately, and can take up to 600 hours or 4,000 miles. The actual time needed depends on operation, history, and age of the equipment. AFC treated fuel completely removes the deposits from fuel injectors, intake and exhaust valves, and other exposed combustion chamber parts of dirty engines, while preventing deposits in new engines.

In older engines the use of AFC treated fuel is even more pronounced than the new ones. The performance of new engines will not degrade and maintenance will remain at a minimum. A gasoline engine will not experience an octane requirement increase.

Fuel treated with AFC Combustion Catalyst burns completely so that new engines stay clean, and older, dirty engines become clean. AFC is the most cost effective way to conserve energy and protect the environment while enhancing performance and engine life.

The Effects of AFC Series on SOx

The treatment of carbon based fuels with AFC has a significant effect on trace sulfur combustion chemistry. In diesel engines, gasoline engines and open flame applications (boilers) the use of AFC treated fuel will significantly reduce sulfur oxide (SOx) emissions, and related sulfur acid corrosion problems.

AFC does not react with the sulfur in the fuel nor does AFC have any effect on the sulfur content of the fuel. AFC does not effect fuel specifications at recommended treatment levels. Fuel containing one percent sulfur prior to AFC treatment will still contain one percent sulfur after AFC treatment. However, the use of AFC will determine where the sulfur ends up and what its chemical state will be after combustion.

The combustion of sulfur in fuels invariably leads to the formation of sulfur dioxide S + O2 –>SO2 (1) and sometimes sulfur trioxide 2SO2 + O2 –>2SO3 (2). Sulfur trioxide formation is catalyzed by vanadium pentoxide (V5+ ). This is the most stable oxidation product of vanadium, when vanadium containing fuels are burned in air 4V + 5O2 –>2V2O5 (3). The catalytic effect is thought to relate to the reversible dissociation 2V2O5 –>2V2O4 + O2 (4) at temperatures between 700o -1125o C. The sulfur trioxide reacts with water vapor to form sulfuric acid SO3 + H2O –>H2SO4 (5) which is primarily responsible for acid corrosion problems in combustion equipment.

AFC affects the production of gaseous SOx emissions. It enhances the formation of CO2 during the combustion phase thus limiting the amount of SOx produced during the exhaust phase. The increased production of CO2 reduces the amount of excess O2 available for other reactions. The difference in the amount of CO2 produced during the combustion and the exhaust phases correlates to a temperature differential. This temperature differential results in lower exhaust temperatures and shorter heat transfer times.

Minerals contained in fuel are generally oxidized to metal oxides during the combustion process. When vanadium is oxidized to V5+ the production of sulfur trioxide increases due to reversible dissociation, and sulfuric acid is ultimately formed. The use of AFC inhibits the formation and reversible dissociation of V5+ during the exhaust phase by limiting the available O2, high temperatures, and time periods needed for these reactions to occur.

This greatly reduces the catalytic effect V5+ has on the formation of Sulfur trioxide and thus the formation of sulfuric acid. By reducing the catalytic effect of vanadium, AFC promotes the combination of SOx compounds with other minerals in the fuel such as Na and Ni. This leads to the formation of stable mineral salts and mixed mineral sulfates found in the clinker or fly ash.

In this manner, AFC decreases the gaseous sulfur emissions by increasing the particulate portion of the combustion residue products. AFC treated fuels will therefore show slightly higher sulfate content in the ash than untreated fuel.

The Effects of AFC on NOx

The formation of NOx takes when combustion temperatures reach above 2500 deg. F and pressures are the highest. This especially occurs when the engine is under high load or wide open throttle. NOx formation is influenced by available excess oxygen, time, and deposit buildup.

AFC significantly lowers the amount of NOx production in internal combustion engines and open flame boilers.

This reduction correlates with combustion deposit removal. Carbon deposit build up in the combustion chamber causes higher compression. This directly affects the factors responsible for the formation of NOx and supports a direct connection between NOx emissions and deposits. This connection is supported by the fact that clean engines using AFC treated fuel produce very low amounts of NOx. The process by which AFC inhibits the formation of NOx is a direct result of the process by which it removes existing and prevents the formation of new deposits, namely through the promotion of CO2 production.

AFC affects the three main factors enhancing the formation of NOx. Fuel has a finite amount of energy, which is released through the production of CO2. AFC promotes the formation of CO2 during the combustion phase. If more CO2 or energy is produced during the combustion phase then less is available to be released during the exhaust phase. The difference in the amount of energy released during the two phases correlates to a temperature differential. This temperature differential, its magnitude and cause are important for three reasons.

Lower exhaust temperature. If the temperature of the combustion phase rises due to increased CO2 production then the temperature of the exhaust phase will go down. This denies the nitrogen molecules the high temperatures needed to form NOx compounds. Lower temperatures slow down the production of NOx by requiring more time for the reactions to take place. The greater the amount energy released during the combustion phase and the associated lower exhaust gas temperature the lower the rate of NOx production will be.

Shorter heat transfer time. The greater the magnitude of the temperature difference, the shorter the heat transfer time becomes. Increase in heat transfer to the surrounding engine components during combustion will decrease exhaust temperature and time for the conversion of nitrogen to NOx compounds. The shorter the heat transfer time the lower the NOx emissions.

Oxygen depletion. Increasing the production of CO2 uses up more of the available oxygen. AFC promotes the production of CO2 during the combustion phase, lowering oxygen availability for NOx reactions during the exhaust phase. Less available oxygen results in lower NOX emissions.

The combination of lower exhaust temperatures, shorter heat transfer time, less available oxygen, and the complete removal of carbon deposits cause a very significant reduction of NOx emissions.

The Effects of AFC on Low Sulfur Fuels

The sulfur content of diesel fuel became a major concern due to its contribution to SOx emissions, especially SO3, which combined with water forms acid. This led to legislation requiring the removal of all but .05% of the sulfur in all diesel fuel used in over the road applications as of October 1, 1993. Regulations will lower allowable sulfur content even more.

Although sulfur itself does not contribute to the performance of a fuel, the fuel components removed together with the sulfur to produce a low sulfur fuel did. These other fuel components have a BTU value, and give the fuel its lubricating properties. The latter was important since many engine manufacturers used the fuel itself to lubricate the fuel pump and other engine parts that come in contact with the fuel. These same components also provide an important portion of the total energy content of the fuel.

Low sulfur fuels have a lower BTU value, a lower lubricity factor and present significant problems for fuel producers and users alike. In the refining process, considerable amounts of extra work are required to remove the sulfur. The process has resulted in extensive re-tooling of the refinery, which has translated into a significant cost increase for the end user. The result is a lower energy yielding fuel at a higher cost.

Cost increase is not the only problem the end user experiences. There was an immediate drop in fuel economy of about 3 to 7%, and a considerable loss of power resulting from the lower BTU value. Because of the reduced lubricating properties of the fuel vital engine parts would wear out more quickly. This could be noticeable in as little as one or two months. The reduction in lubricity has also contributed to a loss in usable power due to the increased friction the engine must overcome. Even a perfectly tuned engine would experience a noticeable drop in efficiency.

The traditional solution had been to add lubricity and anti-wear additive packages to the fuel. AFC contains a premium lubricity and anti-wear additive package correcting the friction and wear problems.

AFC increases fuel economy of engines, turbines and burners. Lower fuel consumption to obtain the same energy output, immediately translates into lower overall emissions.

AFC keeps the engine clean and free of deposits, which lowers maintenance and operating cost. The lubrication oil of engines using AFC stays significantly cleaner and last much longer. Regardless of the type of fuel used, AFC treated fuel will perform better than non-treated fuel. The results will always be immediately evident.

In all applications, AFC more than pays for itself. It saves money, and enhances your bottom line.

AFC in Fuels Containing Vanadium and Sulfur

Crude oils from Alberta, Canada and from Venezuela contain considerable amounts of dissolved vanadium oxides. Normal refinery practice does not provide for the removal of these vanadium oxides. In fact, a major source of commercial vanadium is derived from the fly ash from burning Canadian crude.

In an engine where there is no catalysis for the fuel combustion, unused oxygen can cause the vanadium (oxidation state of three) to be oxidized to vanadium pentoxide, V2O5. This V2O5 can be a problem in itself because it deposits as a hard coating on the surface on the combustion chamber walls. Under many circumstances it has to be manually chiseled off.

If an engine is already damaged by vanadium deposits (V2O5) it is unlikely that AFC can burn off these deposits. Whereas, if the deposits were carbon, adding AFC to the fuel will definitely burn off these carbon deposits.

In addition, the presence of V2O5 can catalyze the transformation of sulfur dioxide, SO2, to form sulfur trioxide, SO3. This is important because sulfur trioxide (SO3) and water gives the highly corrosive sulfuric acid.

Since water is one of the products of hydrocarbon combustion, much damage occurs to all metal parts of the combustion chamber and the exhaust system, resulting from the acid that is produced when vanadium is in the fuel.

The use of AFC results in the complete use of the oxygen present in combustion, leaving little or no oxygen to oxidize the mixed vanadium oxides to the V2O5. By using up all the available oxygen to burn the fuel completely, there is little or no oxygen left over to oxidize the SO2 to SO3 whether V2O5 is present or not.

In new engines and boilers, the use of AFC, will significantly diminish the formation and deposits of V2O5, and therefore prevent production of SO3 and the resultant acids. This clearly and significantly diminishes engine damage caused by acidic corrosion.

As a result, engine life and overhaul cycles will be dramatically extended, while engine maintenance, down time, and overall cost of operations will be significantly reduced. The cost of AFC is more than justified on the basis of its effect on preventing the oxidation of the vanadium oxides and sulfur which are very difficult to remove from fuels.

Pour Point and Cloud Point

The pour point is the lowest temperature at which a petroleum product will begin to flow. Pour point is measured at intervals of 5o F. This interval gives a range in which to account for error inherent in the measuring procedure. A sample with a pour point of 10.5o F and a sample with a pour point of 14.5o F would be labeled as having a pour point of 15o F. Even with the 4o difference they would be considered the same. However, a sample with a pour point of 15.5o F would be labeled as having a pour point of 20o F even though it is only 1o higher than the 14.5o F sample mentioned before. Due to experimental and operator error, sample variations of one interval are not considered significant. Since the measured values for the two samples are only one interval apart the difference is not significant.

The cloud point is the temperature at which wax crystals begin to form in a petroleum product as it is cooled. Cloud point is measured at intervals of 2o F. An example similar to the one used illustrating the pour point procedure applies here. Differences of one interval are not considered significant. Wax crystals depend on nucleation sites to initiate growth. The difference in the cloud points of the two samples is explained by the fact that any fuel additive will increase the number of nucleation sites, which initiate clouding. A change in temperature at which clouding starts to occur is therefore expected upon addition of any additive. The difference between the cloud point values for the two samples is not abnormal and is not significant.

AFC Series Fuel Catalyst — An Alternative Technology

An average reduction of five (5) to ten (10) percent in the consumption of petroleum based fuels by engines that have not historically and periodically been treated with a fuel system cleaner is realistic and a very significant reduction of emissions is possible. All we need to do is treat our fuel with AFC Series Fuel Catalyst 705 or 710.

AFC contains a multi component combustion catalyst, which promotes the removal of engine deposits especially those in the combustion chamber. While removing deposits, AFC treated fuel burns cleaner and more completely, thus eliminating the formation of new deposits. New engines stay clean and older engines become clean. Initially the use AFC treated fuel will often show reductions in fuel consumption far greater than the average five (5) to ten (10) percent. The reduction of emission will increase with the removal of the existing deposits.

In addition, the use of AFC treated fuel will significantly lower equipment operating and maintenance costs, while engine life can be more than doubled. There is less wear on the engine parts and engine oil stays cleaner much longer. When disassembling an engine, a simple wipe down with a shop cloth will show that the parts look as good as new, often with all the serial numbers clearly readable and machining marks still clearly visible.

AFC is extremely cost effective technology. This complete additive package improves fuel consumption and reduces emissions. It extends engine life, decontaminates and cleans the total fuel system, dissolves tank sludge, lowers operating and maintenance cost, while enhancing your bottom line. The AFC additive package perfectly complements the benefits afforded by the LG-X Series of Magnetic Fuel Conditioners.

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