Metal-fuel additives

In this chapter the performance of plalinum/base metal fuel additive-filter systems is discussed with studies on a pilot engine as a basis. It will be compared to the performance of cerium, iron, and copper base metal additives, the latter two also in combination with platinum. The background of the difference in performance of the platinum/base metal combinations is discussed with results from flow-reactor experiments as a basis. 

The NOx that is present in diesel exhaust gas, can be an advantage in the oxidation of soot. Several studies report an important increase of catalytic soot combustion by addition of NO to the gas phase [2, 7], Probably an oxidation cycle with NO as an intermediate for oxygen transfer plays an important role. This cycle can be catalysed at one or more stages. The oxidation of NO to NO2 can be catalysed, but also the subsequent oxidation of soot by NO2 can be catalysed. This observation is confirmed by very recent experiments with bi-metallic fuel additives [8]. 

Up to now, the most effective way to achieve sufficiently good contact between the catalyst and the soot is the application of a metal fuel additive [2]. The high activity can be explained as follows. The organo-metalhc compound in the additive decomposes and the organic part is completely oxidized in the engine combustion chamber. The residual metallic part is enclosed in the soot at the moment of nucleation and subsequent particulate growth. This results in a high dispersion of the metal in the soot and thus in the ultimate contact between catalyst and soot. 

The PSA system consists of using metal-fuel additives to obtain soot particles with catalytically active metak well embedded in the structure. A DPF k used to collect the metal catalyst-containing soot particles and, once filter regeneration is required, extra fuel is injected and its exothermic combustion initiates the catalytic combustion of soot. 

Pentanedione is widely used in extraction processes for the separation and purification of metals because of its abiUty to form covalent metal chelates. It is also used as an intermediate in the production of heterocycHc substances and dyes, as a fuel additive (324), and in metal plating and resin modification. 

Uses. Magnesium alkyls are used as polymerization catalysts for alpha-alkenes and dienes, such as the polymerization of ethylene (qv), and in combination with aluminum alkyls and the transition-metal haUdes (16—18). Magnesium alkyls have been used in conjunction with other compounds in the polymerization of alkene oxides, alkene sulfides, acrylonitrile (qv), and polar vinyl monomers (19—22). Magnesium alkyls can be used as a Hquid detergents (23). Also, magnesium alkyls have been used as fuel additives and for the suppression of soot in combustion of residual furnace oil (24). 

Chlorotoluene isomer mixtures, especially those containing a relatively high amount of o-chlorotoluene, are widely used as solvents in industry for such purposes as metal-cleaning formulations, railroad industrial cleaners, diesel fuel additives, carbon removal procedures, paint thinners, and agricultural chemicals. Halso 99 andHalso 125 are examples of such solvents. 

With the increasing emphasis on energy conservation and environmental considerations, additives for fuels that can correct combustion-related problems have aroused considerable interest. Many commercial fuel additives are combinations of organometaHics, dispersants, emulsifiers, and carrier solvents. The organometaHic, often a metal soap, acts as a combustion catalyst, increasing efficiency with reduction of smoke, deposits, and corrosion. 

CP-1 was assembled in an approximately spherical shape with the purest graphite in the center. About 6 tons of luanium metal fuel was used, in addition to approximately 40.5 tons of uranium oxide fuel. The lowest point of the reactor rested on the floor and the periphery was supported on a wooden structure. The whole pile was surrounded by a tent of mbberized balloon fabric so that neutron absorbing air could be evacuated. About 75 layers of 10.48-cm (4.125-in.) graphite bricks would have been required to complete the 790-cm diameter sphere. However, criticality was achieved at layer 56 without the need to evacuate the air, and assembly was discontinued at layer 57. The core then had an ellipsoidal cross section, with a polar radius of 209 cm and an equatorial radius of309 cm [20]. CP-1 was operated at low power (0.5 W) for several days. Fortuitously, it was found that the nuclear chain reaction could be controlled with cadmium strips which were inserted into the reactor to absorb neutrons and hence reduce the value of k to considerably less than 1. The pile was then disassembled and rebuilt at what is now the site of Argonne National Laboratory, U.S.A, with a concrete biological shield. Designated CP-2, the pile eventually reached a power level of 100 kW [22]. 

The primary ingredients of most fuel additive formulations almost always include metals such as iron, copper, manganese, magnesium, or cerium. Depending on the form of the treatment, these metals can be present in several forms, including ... 

The combustion temperature of soot particulates can be lowered by the addition of an oxidation catalyst in the form of fuel additives[2], by spraying metal salt solution on an accumulated soot or by the impregnation of filter walls with an oxidation catalyst. For the last option, oxides of supported metals are considered to be... 

Molilat-2M Metal-depositing additive for recovering compression in the cylinders and pressure in the lubrication system of worn engines. Improves power performance, saves fuel and oil, reduces noise and smoking of the exhaust. Guaranteed compatibility with all mineral oils. 

Eolys A process for removing 80 to 90 percent of the particulate carbon from diesel exhaust gases. It uses a catalytic fuel additive containing cerium. Developed by Rhone-Poulenc in 1995 and licensed to Sumitomo Metal Mining Company in Japan in 1996. 

Metalation, benzene, 3 603-604 Metal-based fuel additives, 10 54 Metal-bearing wastes, 21 388-389, 406-407... 

While some metals are nutritionally important, there is another group with no beneficial biological effects and in some cases serious toxic effects. Our complex relationship with metals is well illustrated by lead, which we have used for a variety of purposes since ancient times. In the last hundred years, lead was extensively used in paint and as a gasoline fuel additive. In the last 30 years, it was recognized... 

In addition to ionic solids, covalent molecules containing halogen atoms (primarily F and Cl) can function as "oxidizers" in pyrotechnic compositions, especially with active metal fuels. Examples of this are the use of hexachloroethane (C with zinc... 

The use of chlorate or perchlorate oxidizers (KCIO 3> KC10 , etc.) is one way to introduce chlorine atoms into the pyrotechnic flame. Another method is to incorporate a chlorine-rich organic compound into the mixture. Table 7.8 lists some of the chlorine donors commonly used in pyrotechnic mixtures. A dramatic increase in color quality can be achieved by the addition of a small percentage of one of these materials into a mixture. Shimizu recommends the addition of 2-3% organic chlorine donor into compositions that don t contain a metallic fuel, and the addition of 10-15% chlorine donor into the high temperature mixtures containing metallic fuels [11]. 

It is unique because of its powerful hydrogen bonding character and its distinct polarity. However, in fuel systems, these characteristics of water make it a source of a variety of problems. Corrosion of metal fuel system components, emulsification with fuel performance additives, and ice formation in fuel lines are some of the problems directly related to the presence of water in fuel. 

Additive A chemical substance added to a product to impart or improve certain properties. Typical fuel additives include antioxidants, cetane improvers, corrosion inhibitors, demulsifiers, detergents, dyes, metal deactivators, octane improvers, and wax crystal modifiers. 

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