Ethylene world production

Ethylene oxide has been produced commercially by two basic routes the ethylene chlorohydrin and direct oxidation processes. The chlorohydrin process was first iatroduced dufing World War I ia Germany by Badische Anilin-und Soda-Eabfik (BASE) and others (95). The process iavolves the reaction of ethylene with hypochlorous acid followed by dehydrochlofination of the resulting chlorohydrin with lime to produce ethylene oxide and calcium chloride. Union Carbide Corp. was the first to commercialize this process ia the United States ia 1925. The chlorohydrin process is not economically competitive, and was quickly replaced by the direct oxidation process as the dominant technology. At the present time, all the ethylene oxide production ia the world is achieved by the direct oxidation process. 

United States production of ethylene oxide in 1990 was 2.86 x 10 metric tons. Approximately 16% of the United States ethylene (qv) production is consumed in ethylene oxidation, making ethylene oxide the second largest derivative of ethylene, surpassed only by polyethylene (see Olefin polymers). World ethylene oxide capacity is estimated by country in Table 11. Total world capacity in 1992 was ca 9.6 x 10 metric tons. 

Table 11. World Production Capacities for Ethylene Oxide ...

Current world production of ethylene glycol is approximately 15 billion pounds. Most of that is used for producing polyethylene terephtha-late (PET) resins (for fiber, film, bottles), antifreeze, and other products. Approximately 50% of the world EG was consumed in the manufacture of polyester fibers and another 25% went into the antifreeze. 

In 2002, the world production of polymers (not including synthetic libers and rubbers) was ca. 190 million metric tons. Of these, the combined production of poly(ethylene terephthalate), low- and high-density polyethyelene, polypropylene, poly(vinyl chloride), polystyrene, and polyurethane was 152.3 milhon metric tons [1]. These synthetic, petroleum-based polymers are used, inter alia, as engineering plastics, for packing, in the construction-, car-, truck- and food-industry. They are chemically very stable, and can be processed by injection molding, and by extrusion from the melt in a variety of forms. These attractive features, however, are associated with two main problems ... 

Oxidation is the first step for producing molecules with a very wide range of functional groups because oxygenated compounds are precursors to many other products. For example, alcohols may be converted to ethers, esters, alkenes, and, via nucleophilic substitution, to halogenated or amine products. Ketones and aldehydes may be used in condensation reactions to form new C-C double bonds, epoxides may be ring opened to form diols and polymers, and, finally, carboxylic acids are routinely converted to esters, amides, acid chlorides and acid anhydrides. Oxidation reactions are some of the largest scale industrial processes in synthetic chemistry, and the production of alcohols, ketones, aldehydes, epoxides and carboxylic acids is performed on a mammoth scale. For example, world production of ethylene oxide is estimated at 58 million tonnes, 2 million tonnes of adipic acid are made, mainly as a precursor in the synthesis of nylons, and 8 million tonnes of terephthalic acid are produced each year, mainly for the production of polyethylene terephthalate) [1]. 

Since 1961, the industrial importance of the hydroformylation reaction has been threatened by newer processes (19) such as the Ziegler polymerization of ethylene, the Wacker process, and the direct oxidation of petroleum (153). The industrial aspects of the Oxo reaction were reviewed in 1965 when the world production capacity for Oxo products was estimated at 0.5 million tons per year (39). 

Ethylene oxide is listed among the 25 chemicals of highest production volume in the U.S., whose production capacity is estimated at 6.1 billion lb/yr. This is about 43) of world production capacity (refs. 76a, b). At room temperature and atmospheric pressure ethylene oxide (ETO) is a colorless gas. Is has a characteristic odor, generally described at ether-like, whose detection threshold varies widely in humans. The mean detection threshold is estimated at 700 ppm (1260 mg/m3). It is miscible with water, alcohol, ether find most other organic solvents. 

Taking a different course than Algeria with its liquefied natural gas, the Gulf States have thus upgraded their natural resources and already account for 10 percent, 5 percent, and 4 percent of world production of methanol, ethylene, and polyethylene respectively. 

Most vinyl acetate is converted into polyvinyl acetate (PVA) which is used in the manufacture of dispersions for paints and binders and as a raw material for paints. It is also copolymerized with vinyl chloride and ethylene and to a lesser extent with acrylic esters. A substantial proportion of vinyl acetate is converted into polyvinyl alcohol by saponification or transesterification of polyvinyl acetate. The main applications for polyvinyl alcohol are either as raw material for adhesives or for fibres. It is also employed in textile finishing and paper glueing, and as a dispersion agent (protective colloid). The world production capacity of PVA was 4.35 Mt/a in 2005, of which 2.1 Mt were converted into polyvinyl alcohol. 

Hexadiene in its E form is manufactured from butadiene and ethylene (Equation 20). The Z isomer must be kept to a minimum owing to its adverse effect on polymerization. The reaction, first reported in 1961, was commercialized by DuPont. The present world production is estimated around 2.5-3 kt/a. Various metal salts (Ni, Co, Fe) were tested, but the best results were obtained with RhCls.hydrate. 

Shell manufactures a-olefins from ethylene by oligomerization with a nickel catalyst in a polar solvent such as ethylene glycol, under the conditions specified in Equation 27. This corresponds to the first part of the SHOP process (Shell Higher Olefin Process) described in Section 6.2.2. The world production is estimated to be over 1 Mt/a. 

The future of the commercial acetaldehyde processes mainly depends on the availability of cheap ethylene. Acetaldehyde has been replaced as a precursor for 2-ethylhexanol ( aldol route ) or acetic acid (via oxidation cf. Sections 2.1.2.1 and 2.4.4). New processes for the manufacture of acetic acid are the Monsanto process (carbonylation of methanol, cf. Section 2.1.2.1), the Showa Denko one-step gas-phase oxidation of ethylene with a Pd-heteropolyacid catalyst [75, 76], and Wacker butene oxidation [77]. Other outlets for acetaldehyde such as pentaerythritol and pyridines cannot fill the large world production capacities. Only the present low price of ethylene keeps the Wacker process still attractive. 

Ethylene is the largest volume organic chemical product, with world production over 50 billion pounds per year. It is normally produced by steam cracking of ethane or heavier hydrocarbons. This process is quite energy and capital intensive. 

In the US, ethylene monomer derived from natural gas is primarily used to produce PE though other fossil fuels may also be used for the purpose. The annual world production of PE is approximately 100 MMT. 

World production of vinyl acetate monomer was 4 x 10 t in 1999. This represented 84% of the total capacity. In 2002, North American companies produced 1654 X 10 t of vinyl acetate. See Table 5 for producers and their capacities (22). The dominant method of production in North America is by the reaction of ethylene with acetic acid and oxygen in the presence of palladium catalyst. New construction in recent years has been focused in southeast asia, although European and North American producers have expanded their plants. 

The only hydrocarbon produced directly from natural gas (methane) is acetylene (world production 1998 about 120000ta , Talbiersky, 2006). Production is based on partial oxidation where about one-third of natural gas (methane) is converted into acetylene, while the rest is burned to reach a temperature of about 1500 °C. The entire process only takes a few milliseconds. Acetylene is also produced in arc furnaces. Up to the 1960s, acetylene was an important intermediate, but nowadays its relevance is small compared to olefins such as ethylene and propylene. Today, the most important product from acetylene is 1,4-butandiol, which is used for production of polyurethane and polyester plastics. Acetylene is also used for gas welding, as combustion with oxygen produces a flame of over 3000 °C. 

These reactions include the Phillips process, i.e. the polymerization of ethylene at Tk 105 °C and pressures aroimd 30 bar [4, 5]. Of course, this procedure attracted our special attention. In spite of its worldwide use, which makes more than 1/4 of the world production of HDPE, and after almost four decades of research the mechanism of the reaction is still a matter of controversial discussions [1, 2]. The varying results are partially due to different experimental starting points (e.g. different supports), occasionally also to the use of inadequate measurements, and the neglect of involved parameters. 

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