Propane butane blend

The client requires an effective antiperspirant product which is to be dispensed as an aerosol spray using a propane-butane blend as the propellent gas. Figure 9.4 illustrates the basic components of an aerosol. 

Hydroca.rbons. Hydrocarbonsn such as propane, butane, and isobutane, which find use as propellants, are assigned numbers based upon their vapor pressure in psia at 21°C. For example, as shown in Table 2, aerosol-grade propane is known as A-108, / -butane as A-17. Blends of hydrocarbons, eg, A-46, and blends of hydrocarbons and hydrochlorocarbons orHCFCs are also used. The chief problem associated with hydrocarbon propellants is their flammabihty. 

Propane is usually used in this process although propane—butane mixtures and pentane have been used with some variation in process conditions and hardness of the product. Propane deasphalting is used primarily for cmde oils of relatively low asphalt content, generally <15%. Asphalt produced from this process is normally blended with other asphaltic residua for making paving asphalt. 

Even considering inflation, which caused prices to double between 1971 and 1984, this period saw the price of naphtha triple in real value. This situation encouraged the petrochemical industry to search for other raw materials that could offer a more appropriate economic adequation to market needs. Accordingly, since 197 the trend was established to use heavier fractions produced by oil refining, such as atmospheric gas oil and even vacuum gas oil. More recently, due to the higher recovery of associated gases in the Middle East oil fields, and that of gas condensates in gas fields (North Sea, Indonesia), the European and Japanese petrochemical industries moved towards the use of propane/butane. often blended with naphtha, and even ethane for the North Sea riparian states. However, since the availability and price of these new raw materials, gasoil as well as liquefied petroleum gas. were uncertain and liable to market fluctuations. 

Surrogates of LPG can be made by blending mixtures of propane, butane, and natural gas. The surrogate LPG fuel should closely match the heating value and molecular weight of the actual fuel. 

Cj s and C s include propane, propylene, normal butane, isobutane, and butylene. Propylene and butylene are used to make ethers and alkylate, which are blended to produce high-octane gasoline. Most gas plants also include treating facilities to remove sulfur from these products. 

Polymer gasoline a gasoline produced by polymerization of low-molecular-weight hydrocarbons such as ethylene, propane, and butanes. It is used in small amounts for blending with other gasoline to improve its octane number. 

Figure 5 Alkylation process using sulfuric acid. Butanes and butenes react in the presence of a catalyst (sulfuric acid) to form an alkylate for use as a gasoline blending component. Propane and butane are also produced. (From Ref. 6.)...

The fractionation section of the alkylation plant consists of a deisobutanizer, a debutanizer, and a rerun tower in series, and a depropanizer. The deisobutanizer overhead, which contains about 90% isobutane, recycles to the reactor. The deisobutanizer bottoms stream passes to the debutanizer, which removes normal butane diluent as an overhead stream. The debutanizer bottoms or raw alkylate stream then goes to a rerun tower for removal of the high boiling alkylate bottoms or trimers. The rerun overhead requires no further treatment to be satisfactory as an aviation gasoline blending stock. The depropanizer removes propane diluent from a slip-stream portion of the recycle isobutane stream to prevent propane build-up in the reaction system. 

LPG is a blend of propane and butane obtained as secondary products of natural-gas exploration or during crude oil processing. For this reason LPG is included usually in alternative fuels. Although the combustion properties of LPG are excellent, its wider usage is prevented by supply limitations and safety problems. 

Isotactic Polystyrene. The familiar steam molding of pre-expanded particles has so far not been applied successfully to isotactic polystyrene. However, the polymer has been foamed, according to three disclosed methods. For example, finely divided acetone-insoluble polymer, with a melting point in excess of 200°C., is blended with a liquid selected from methylene chloride, aromatic hydrocarbons, or halogenated aromatic hydrocarbons. This blend is then heated (84). A mixture of molten polymer and methyl chloride, propane, or butane is suddenly depressurized (8). Foam may also be generated in a continuous manner directly from a butyllithium-initiated polymerization conducted in the presence of a 4/1 blend of benzene and petroleum ether (15). 

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