Treating processes propane

When the diethyl ether distillate from this trapping process is judged to be virtually trimethylindium free, the flask containing the diethyl ether, 2 or 3, is filled to atmospheric pressure with argon, removed from the assembly, and its contents cautiously treated with propan-2-ol to destroy any remaining traces of trimethylindium dissolved in the diethyl ether. 

The charge to the unit is treated refinery propane-propylene along with recycle benzene from the recycle column overhead. Make-up benzene is added to the recycle. Nitration-grade benzene is usually used so that a drag stream of benzene is not required to remove contaminants from the unit. Table IX shows the component analysis of the various streams in the cumene process. 

LPG is a by-product of natural gas treating processes or an incidental gas recovered during the oil extraction process. It generally comprises propane, butane, or a combination of both. As the spot market price for propane and butane varies with the seasonal demand, the receiving terminal and power plant facilities must be designed to handle 100 percent propane, 100 percent butane, or any combination of the two. 

Hiadered esters are also produced from and Cg a-olefias. These olefias are coaverted iato C —C fatty acids by the oxo process the acids are thea treated with polyols such as peataerythritol and trimethylol propane to produce hindered esters, which find use ia lubricants for jet engines and other high performance appHcations. 

Thermal polymerization is not as effective as catalytic polymerization but has the advantage that it can be used to polymerize saturated materials that caimot be induced to react by catalysts. The process consists of the vapor-phase cracking of, for example, propane and butane, followed by prolonged periods at high temperature (510—595°C) for the reactions to proceed to near completion. Olefins can also be conveniendy polymerized by means of an acid catalyst. Thus, the treated olefin-rich feed stream is contacted with a catalyst, such as sulfuric acid, copper pyrophosphate, or phosphoric acid, at 150—220°C and 1035—8275 kPa (150—1200 psi), depending on feedstock and product requirement. 

After epoxidation, propylene oxide, excess propylene, and propane are distilled overhead. Propane is purged from the process propylene is recycled to the epoxidation reactor. The bottoms Hquid is treated with a base, such as sodium hydroxide, to neutralize the acids. Acids in this stream cause dehydration of the 1-phenylethanol to styrene. The styrene readily polymerizes under these conditions (177—179). Neutralization, along with water washing, allows phase separation such that the salts and molybdenum catalyst remain in the aqueous phase (179). Dissolved organics in the aqueous phase ate further recovered by treatment with sulfuric acid and phase separation. The organic phase is then distilled to recover 1-phenylethanol overhead. The heavy bottoms are burned for fuel (180,181). 

The use of methane, ethane, ethylene, propylene, and propane pure light hydrocarbons as refrigerants is quite common, practical, and economical for many hydrocarbon processing plants. Examples include ethylene manufacture from cracking some feedstock, ethylene or other hydrocarbon recycle purification plants, gas-treating plants, and petroleum refineries. 

Higher molecular weight hydrocarbons present in natural gases are important fuels as well as chemical feedstocks and are normally recovered as natural gas liquids. For example, ethane may be separated for use as a feedstock for steam cracking for the production of ethylene. Propane and butane are recovered from natural gas and sold as liquefied petroleum gas (LPG). Before natural gas is used it must be processed or treated to remove the impurities and to recover the heavier hydrocarbons (heavier than methane). The 1998 U.S. gas consumption was approximately 22.5 trillion ft. ... 

The general treatment of the hydrocarbon stream leaving the alkylation reactor is similar in all processes. First, the acid and hydrocarbon phases have to be separated in a settler. The hydrocarbon stream is fractionated in one or more columns to separate the alkylate from recycle isobutane as well as from propane, n-butane, and (sometimes) isopentane. Because HF processes operate at higher isobutane/alkene ratios than H2S04 processes, they require larger separation units. All hydrocarbon streams have to be treated to remove impurity acids and esters. 

Downstream of the compressor is a series of fractionators (generally the tallest towers in an ethylene plant) which separate the methane and hydrogen, the ethylene, the ethane, and the propane and heavier. All are heavy metallurgy to handle the pressures and insulated to maintain the low temperatures. There s also an acetylene hydrogenator or converter in there. Trace (very small) amounts of acetylene in ethylene can really clobber some of the ethylene derivative processes, particularly polyethylene manufacture. So the stream is treated with hydrogen over a catalyst to convert the little acetylene present into ethylene. 

To extract natural gas, holes are drilled deep into the Earth and giant pipes are inserted. Once a gas deposit is located, gas flows up the pipeline and is treated at processing plants. Other gases, such as butane and propane, are separated from the methane. 

Processes that have been combined with propane deasphalting include acid treating, cold fractionation of heavy lubricating oils, and selective solvent refining. 

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