Propylene tetramer(C9H13), an olefin(alkene), is produced by the polymerization of propylene, which is also known as propene. A tetramer is actually a polymer made up of four identical monomers, thus in this case, propylene tetramer consists of four propylene units bonded together.
In industrial polymerization, the temperature is moderated so as to induce polymerization. Propylene is first heated, then later cooled and passed through a catalyst bed. The catalysts help to speed up the rate of reaction, reducing total amount of time required for the reaction to take place.
Among other products, propylene tetramer can be used to produce dodecylphenol. Dodecylphenol is produced by the alkylation of phenol using propylene tetramer, which is also known as dodecene. (Alkyl groups form a homologous series, and its general formula is denoted as CnH2n+1.)
Its main application is in fuel and lubricant additives.
Dodecylphenol is used mainly in the production of additives for engine fuels and lubricant oils. Fuel and lubricant additives are added to fuel and lubricants to ensure the optimum performance of the fuel or lubricant, by giving them new properties such as detergency and oxidation stability. It also helps to reduce the emission of pollutants from the engine, as well as lowering fuel consumption while maintaining high performance. In short, it improves on existing areas which perform weakly under normal circumstances.
Chevron Oronite produces diesel fuel additives under the product line Oronite Diesel Additive (ODA). There are four main types of diesel fuel additives, namely engine performance, fuel handling, fuel stability and contaminant control additives.Engine performance can be marred by system deposits in the vehicle engine, which are formed due to the use of low-grade fuel. They disrupt fuel flow in the fuel injector (this controls the intake of fuel of the engine), and in the intake valves and the combustion chamber, deposits also lead to problems like poor driveability, loss of power and increased emissions. When engine performance additives are added, the deposits are removed and the engine system is cleaned. Lubricity additives are also added to lubricate some severely hydrotreated diesel fuels. This helps to lubricate the engine parts, reducing wear and tear and so extending the parts’ life.
There is a wide range of fuel handling additives, for example low temperature operability additives, de-icing additives and anti-foam additives. Anti-foam additives reduce foaming of fuels when they are pumped into vehicles, allowing for them to be transferred from one place to another better. De-icing additives lower the freezing point of water in the fuel, preventing water crystals from forming at low temperatures and blocking the fuel lines or filters, which hampers fuel flow. Low temperature operability additives lower the temperature at which the fuel gels, and also improves its cold flow properties, allowing it for use in low temperature climates.
Unstable fuels can deteriorate and oxidise, forming gums that also can lead to deposits which, as mentioned before, can hinder the fuel flow in the engines. Fuel stability additives mainly work to stop the formation of the gums by blocking the oxidation reactions(by using anti-oxidants) or preventing the deterioration reactions from occurring. As different fuels are produced differently, they would have varying additives for each.
Contaminant control additives are used mainly to deal with problems that do not arise due to the fuel itself, such as corrosion inhibitors, demulsifiers. Demulsifiers are the opposite of emulsifiers, and are used for separating emulsions. Here, it causes the fuel and water phases of the diesel fuel to separate out. Corrosion inhibitors are to prevent the formation of rust within the fuel, as the rust may plug (to fill up and stop) the fuel filters in the engine and reduce engine performance.