Note: Descriptions are shown in the official language in which they were submitted.
21~31~
A Solid Fu~l Additive and M~thod
FiQld o~ th~ InvQntion
This invention relates to a solid fuel additives and to
a method of making a solid fuel additive.
Background of th~ Invention
Many fuel treatment additives have been developed in
recent years; some of which for example modify diesel and
gasoline fuels to prevent freezing, improve efficiency or
power and environmental characteristics. Usually, such
additives are mixed with the fuel in a ratio of approximately
one part per thousand or less, perhaps as little as one part
in ten thousand. For example, additives made by Parrish
Chemical Company of Provo, Utah, and distributed under the
trade namés E~RROX and FPC-l are catalytic agents which, in
concentrations of as little as one part in 5, 000, improve
combustion efficiency and reduce particulate carbon exhaust
emissions. While higher concentrations are tolerable, little
benefit is gained. Since all such additives are relatively
expensive, It is desirable to maintain a mixture
concentration scarcely greater than the effect~ve minimum.
In the most basic method of application, the fuel
treatment is dispen3ed manually by measuring out an
appropriate quantity of additive for the desired
concentration and pouring it into the tank. Of course,
evaporation and spillage that often occurs when manually
dispensing the fuel treatment into the tank of a vehicle, can
be hazardous to the environment, the vehicle, and more
particularly the user.
In United States Patent 5,331, 994 issued July 7, 1994
in the name of Brian W. Petersen et al. an apparatus is
~1431~
disclosed for automatically metering appropriate quantities
of an additive to a working supply of diesel fuel which is
replenished in unpredictable amounts at random intervals, so
as to maintain an accurately controlled additive
5 concentration in the diesel fuel. Although this apparatus
appears to provide its intended function, it is costly way of
introducing fuel additive into the average motorist' s
vehicle. The speclfication of the patent is directed
primarily to use of the apparatus with diesel trucks.
Several years ago, a commercially available product
referred to as "Gasoline Green Beans" were sold in the United
States and in Canada as a gas additive in the form of a wax
tablet that was said to melt when added to a tank of
15 gasoline. The beans were a homogeneous mixture of a
particular fuel additive and paraffin wax. The additive
would have been added to the wax while the wax was in a
substantially liquid state and then mixed to form the
homogeneous mixture. The mixture still in liquid form would
20 be poured into pill or bean shaped forms and allowed to cool.
Once cooled the bean shaped forms were bLister packed and
sold to the public. The product suffered from a variety of
problems. Firstly, the wax beans melted while still in thelr
packaging when left in a car on a warm day and secondly, the
25 wax beans very often did not melt quickly or did not
completely melt when added to fueI in cold weather, thus not
dlspensing the entire additive and increasing the chances of
plugging fuel intake lines located within the tank.
Other similar related products have been described in
U.S. patents 4,515,740 and 4,639,255 entitLed "Method of
Forming Solid Form Fuel Additives", and "Solid Form Additives
and Method of Forming Same", respectively, both issued in
the name of Schuette~ber et al. Both of these patents relate
to the use of paraffin' s with additives and hence would
D
experience the same problems and shortcomings of the wax
beans discussed above.
5 ~tatA ~ of thc Invt~ntion
The invention seeks to overcome or minlmize the above
problems .
In accordance with one aspect of the lnvention, there is
provided, a method of making a solid fuel addltlve comprlslng
the steps of provlding a solid and substantially porous
structural agent of a predetermined size and shape, the
porous structural agent being compatible with, and being
lS soluble and dispersible withln fuels used for internal
combustion engines; providing a liquid fuel additive;
sub~ecting the substantially porous structural agent to the
liquld fuel additlve such that a predetermined amount of the
fuel addltlve is absorbed by the porous structural agent;
20 and meltlng an outer layer of the structural agent
sufficiently to alter the porosity of the outer layer from
being substantially porous to being substantlally non-porous
thereby sealing the outer surface of the structural agent to
prevent evaporatlon or c-ontamlnation of the fuel addltlve
25 withln the structural agent.
Provlding a solid and substantially porous structu~al
agent enables a manufacturer to significantly reduce costs by
utlllzing a simple, efflcient and lnexpenslve method of .
30 absorption to unlte the liquid addltive with the structural
agent. The step of melting an outer layer of the solid and
substantlally porous structural agent to alter t~e poroslty
of the outer layer from belng porous to substantially non-
porous, provides a simple yet effective seal which greatly
35 reduces manufacturing costs and time. Separate coating
21~3~40
products are not requlred to be on inventory and the time
consuming step of applying a coating agent is not required.
Conveniently the step of sub~ecting the substantially
S porous structural agent to the liquid fuel additive includes
immerslng the structural agent in a bath containing the
liquid additive for a period of time sufficient for the
structural agent to absorb a predetermined amount of the
liquid fuel additive.
Advantageously the method includes the step of
separately heating the solid structural agent and the liquid
fuel additive to a temperature within the range of 70-llO F
and preferably to wlthin the range of 85-95 F, prior to
lS immersing the structural agent in a bath containing the
liquid additive. Heating the structural agent and the liquid
additive has the advantageous commercial benefit of
shortening the required absorption time.
Preferably the structural agent is Naphthalene as it is
readily available and gasoline additives for automobile
engines which include naphthalene in their constituents have
been registered at the Amerlcan Environmental Protection
Agency .
Preferably the step of melting an outer layer of the
structural agent includes the step of submersing the solid
structural agent with absorbed fuel additive into a liquid
bath, preferably one of water heated to a temperature within
a range of 1~0-160 F for a duration of less than about 30
seconds to sufficiently melt just the outer layer
In accordance with a further aspect of the invention,
there is provided a solid fuel additive compatible with, and
being soluble and dispersible within fuels used for internal
combustion engines, said solid fuel additive comprising a
4~
.
solid structural agent of a predetermined size and shape, the
solid structural agent having a substantlally porous lnternal
reglon and containing a fuel additive within pores of the
porous internal region and the solid structural agent having
5 a melted substantially non porous outer layer to prevent
evaporatlon or ~ ntAm~ nAtlon of the fuel additive within the
solid structural agent.
Preferably the structural agent ls Naphthalene as
10 it ls readlly available and gasoline addltlves for automoblle
englnes which include naphthalene in their constituents have
been registered at the American Environmental Protection
Agency .
Det~ilQd De~cription
A solid structural agent for carrying a particular fuel
additive is desirable over the relatively soft and heat
20 sensitive structural agents used in the prior art.
It is known that certaLn chemical products will not
alter or affect fuels in any negative way when introduced in
small quantities. Such chemical products as Naphthalene and
25 Durine for example are known to be compatible with today' s
engines and will not for example cause engines to fail
current emissions standards. In fact, gasoline additives
for automobile engines which include naphthalene in their
constituents have been registered at the American
30 Environmental Protection Agency EPA.
Additives which are known to be compatible with the
solid structural agents described herein are generally either
Mineral Spirit based or Petroleum Distillate based. Examples
35 of such additives are manufactured and sold under trade names
such as MotoMaster 1~9, Bardahl ~), and STP ~19. Additives sold
~,1431~
under these trade names are designed to clean carburetors,
clean fuel in~ectors, reduce engine knock, clean upper
cylinder regions o~ engines etc. All of these additives are
sold in liquid form and it is believed by the applicant that
for marketing reasons these products are typically sold in
bottles of which only a very small portion of the total
volume is the actual active ingredient or additive. A
concentrated form of the additive or only the `active
ingredlent' portion is really therefore all that is actually
required. A convenient and safe carrier of this active
portion is nee~ed. Considering that many of the more
expenslve additives are added in very small amounts in any
one dose, a 1. 6 gram naphthalene pellet for example will
absorb typically about one third its volume of a liquld
additive.
A solid and substantially porous structural agent is
formed into pellets having a mass of around 1. 6 grams . The
structural agent must be compatible with, soluble and
~0 dispersible within fuels used for internal combustion engines
such as for example Naphthalene or Durene. Naphthalene
pellets may be special ordered and p~rchased from chemical
manufacturers such as `Recho Chem' in Montreal, Canada. A
liquid additive such as that descrlbed in U . S . patent
3, 976, 438, and issued to Eugene Bay on August 24, 1976 is
then brought into contact with the structural agent so as to
be absorbed by the structural agent. Any of a number of
methods for achieving this may be used. For example, an eye
dropper arrangement may be used to place the additive, drop
by drop onto the surface of a pellet so as to enable the
structural agent pellet to absorb the additive. ~he amount of
additive absorbed can be controlled by the number of drops
applied to the surface of the pellet or by the physical size
of the pellet itself, as a pellet will only absorb an amount
up to a predetermined saturation level. A naphthalene pellet
for example when saturated will have absorbed about one third
~31
~,
it' s volume of the additive. A more efficient method is to
immerse the pellets in a container of the additive until the
pellets have absorbed the fuel additive and reached either a
saturation level or have absorbed a predetermined amount.
S This method has the advantage of requLrlng a very simple
apparatus and would be preferred commercially over the eye
dropper method. Preferably though, the pellets and liquid
additive may be warmed before being brought into contact with
each other to increase the rate of absorption of the additive
10 by the pellets. Warm air for example may be used to warm the
pellets and the additive or preferably in the case of
Naphthalene pellets, they may be immersed in water heated to
a predetermined temperature to elevate the pellet temperature
as it is known that Naphthalene does not react with water or
15 absorb it. It has been found that heating the pellets and
the liquid additive to temperatures between 70-ll0 F
provides absorption times acceptable for commercial
operations with temperatures between 85-95 F providing the
most optimum results. Naphthalene pellets having a mass of
20 1. 6 grams heated to 90 F and immersed in an additive (having
mineral spirit or petroleum distillate base) also heated to
90 F will reach an absorption saturation level in
approximately 15-30 minutes. Once the pellets have
absorbed a predetermlned amount of the additive or reached a
25 saturation level, the pellets are substantially ready for use
within a vehicle. Preferably, an added step of melting an
outer layer of the structural agent or pellet sufficiently to
alter the porosity of the outer layer from being
substantially porous to being substantially non-porous
30 effectively seals the outer surface of the structural agent
(pellet) to prevent evaporation or contamination of the fuel
additive within the structural agent (pellet). Further
heating the outer surface of the pellet to melt the outer
layer may be achieved using hot air but preferably the solid
35 structural agent with absorbed fuel additive is submersed
into a heated bath of water for a duration sufficient to melt
~431~0
.
just the outer layer. For example a Naphthalene pellet
submersed in a bath o~ water within a range of 1~0-160 F for
about 30 seconds i9 sufficient to melt and seal the outer
layer .
Melting an outer layer of a substantially porous
structural agent to form a non-porous outer layer which then
can function effectively as a seaL greatly reduces
manufacturing costs. Separate coating products are not
10 requ~red to be on inventory and the time consuming step of
applying a coating agent is not requlred.
For safety reasons it should be noted that an open flame
should not be u3ed to melt the outer surface of the
15 structural agent or to heat the liquid additive as certain
additives and structural agents may be flammable. The flash
point of the liquid additive should be known to the user and
if it is low then the method described herein which does not
heat the liquid additive prior to being brought into contact
20 with the structural agent should be used.
