Petrochemical industry paraffins

Refineries and petrochemical industry Paraffins, olefins, acetylenes, reformer gas, hydrocracking gas, solvents Sweetening of liquid petrol gas and aromatics, removal of CO2 from olefin containing gases, purification of synthesis gas Normal and branched-chain alkanes... 

In 1950 the Fischer-Tropsch synthesis was banned in Germany by the allied forces. Sinarol, a high paraffinic kerosene fraction sold by Shell, was used as a substitute. This ban coincided with the rapid development of the European petrochemical industry, and in due time Fischer-Tropsch synthesis applied to the production of paraffins became uneconomic anyway. After the war there was a steady worldwide increase in the demand for surfactants. In order to continually meet the demand for synthetic detergents, the industry was compelled to find a substitute for /z-paraffin. This was achieved by the oligomerization of the propene part of raffinate gases with phosphoric acid catalyst at 200°C and about 20 bars pressure to produce tetrapropene. Tetrapropene was inexpensive, comprising a defined C cut and an olefinic double bond. Instead of the Lewis acid, aluminum chloride, hydrofluoric acid could now be used as a considerably milder, more economical, and easier-to-handle alkylation catalyst [4],... 

The double bond difference between the olefins and the paraffins is the quintessential difference between the petrochemicals and petroleum products— the petrochemicals industry depends much more on the chemical reactivity of the double-bonded molecules. While paraffins can be manipulated in refineries by separation or reshaping, olefins in a petrochemical plant are usually reacted with other organic compounds or another kind of atom or compound such as oxygen, chlorine, water, ammonia, or more of itself. The results are more complicated compounds useful in an increasing number of chemical applications. More on this in later chapters. 

As with ethane and other paraffin hydrocarbons, propane is an important raw material for the ethylene petrochemical industry. The decomposition of propane in hot tubes to form ethylene also yields another important product, propylene. The oxidation of propane to compounds such as acetaldehyde is also of commercial interest. 

The olefins ethylene and propylene are highly important synthetic chemicals in the petrochemical industry. Large quantities of such chemicals are used as feedstock in the production of polyethylene, polypropylene, and so on [31]. The prime source of lower olefins is the olefin-paraffin mixtures from steam cracking or fluid catalytic cracking in the refining process [32]. Such mixtures are intrinsically difficult to... 

Olefin-paraffin separations represent a class of most important and also most costly separations in the petrochemical industry. Cryogenic distillation has been used for more than 60 years for these separations (Keller et al, 1992). They remain to be the most energy-intensive distillations because of... 

The metal catalyst cracks paraffinic chains longer than C25 and reforms chains shorter than Ce. This is especially important to convert the a-olefin chains (1-alkenes) to saturated alkanes. The catalyst ensures that the final fuel has a carbon chain distribution in the range C8-C25 peaking at Cie (cetane) (Figure 15.8). The catalytic tower uses technology borrowed from the petrochemical industry for the hydrogenated of C=C double bonds, e.g. Raney Nickel or so-called Adams catalyst. 

T he expansion of the petrochemical industry and the accompanying increase in the demand for ethylene, propylene, and butadiene has resulted in renewed interest and research into the pyrolytic reactions of hydrocarbons. Much of this activity has involved paraffin pyrolysis for two reasons saturates make up most of any steam cracker feed and since the pioneering work of Rice 40 years ago, the basic features of paraffin cracking mechanisms have been known (1). The emergence of gas chromatography as a major analytical tool in the past 15 years has made it possible to confirm the basic utility of Rice s hypotheses (see, for example, Ref. 2). 

The associated gas is mainly composed of C1-C4 paraffins. Recently, the methane and ethane in the associated gas have been used effectively by petrochemical industries as a raw material However, propane and butane included about 10 vol % [1] in the associated gas are used only for fuels. Therefore, it is expected that propane and butane will be converted to liquid hydrocarbons, such as aromatics, for the effective total utilization of the associated gas. 

Aromatization of paraffins is one of the most important conversion process for the production of the aromatics which is of great interest in both petroleum (as gasoline blender) and petrochemical industries. The conversion of lower alkanes to higher value products like benzene, toluene and xylenes over zeolite catalysts is well studied reaction [1-4]. A process for the transformation of propane and butane to aromatics has been developed and commercialized jointly by UOP and BP [5]. The technical feasibility of C3-C4 stream aromatization has been demonstrated by 1000 bbl/day Cyclar process at Grangemouth, U.K. and 200 bbl/day Z-forming pilot plant at Kawasaki Refinery of Mitsubishi Oil, Japan. Both these processes employ high silica, medium pore ZSM-5 zeolite based catalysts for aromatization. 

Paraffins - Obsolescent term for saturated hydrocarbons, commonly but not necessarily acyclic. Still widely used in the petrochemical industry, where the term designates acyclic saturated hydrocarbons, and stands in contradistinction to naphthenes. [5]... 

The separation of olefin and paraffins, particularly the C2 (ethane/ethene) and C3 (propane/propene) pairs is an extremely important and demanding separation in die petrochemical industry (56). It is currently performed via cryogenic distillation and is thus energy (and capital) intensive. Thus, the use of zeolites to perform this separation has been studied intensely. While many zeolites have been investigated to selectively adsorb the olefin, PSA-type approaches are not currently used for this separation. More recently, small-pore zeolites have been reported wherein a clear kinetic separation is observed in that the diffusion of propylene is dramatically faster than that of propane (57, 58). This potentially represents a significant breakthrough in the field. 

The separation of olefin/paraffin gas mixtures is one of the most energy-intensive processes in the petrochemicals industry, because it is mainly performed by cryogenic distillations. Membrane processes using the concept of facilitated transport have been considered as an intriguing alternative to cryogenic distillation, as they can simultaneously improve both permeability and selectivity. Silver ions incorporated in liquid membranes act as olefin... 

Olefins such as ethylene and propylene are produced in the petrochemical industry by steam cracking of paraffins, followed by repeated compression and distillation to separate the complex vapor mixtures. Ethylene is used to create ethylene oxide, and polyethylene, while propylene is the second highest volume petrochemical feedstock after ethylene and is used for the production of a wide variety of polymers. 

Even as early as 1939, the soap industry began to create laundry detergents using surfactants that were supplied to the soap manufacturers by the petrochemical industry. Because the cleaning formulations prodnced from these synthetic detergents were a substantial improvement over soap products in use at the time, they soon gave rise to a global surfactant industry based on branched alkyl benzene (BAB) derived from branched paraffins. 

A recent study estimated that about 10,000 BTU of energy is used armually for olefin-paraffin distillation. The distillation process is used commercially in this separation process. However, membrane separation with low energy consttmption and with relative ease in operation, can be significantly competitive with the distillation process [6]. Therefore, carbon membranes can contribute greatly to the petrochemical industry. 

The separation of hydrocarbons is one of the most important chemical processes routinely carried out in the petrochemical industry. Hydrocarbons, as the name suggests, are exclusively made up of carbon and hydrogen atoms that can be broadly classified based on their chemical nature alkanes or paraffins (general formula C H2 +2 example ethane, C2Hg), alkenes or olefins (general formula example ethene,... 

In the 19th century, oil was discovered. Originally extracted and refined to produce paraffin for lamps and heating, oil was rapidly adopted as a source of energy in motor cars. Eventually, techniques were developed that allowed oil to be converted to chemicals, and its availability and financial accessibility allowed the petrochemical industry to grow at a tremendous rate. Developments in the modem plastics, rubbers, and fibers industries led to significant demand growth for synthetic materials. 

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