Acetaldehyde production capacity

Acetaldehyde, first used extensively during World War I as a starting material for making acetone [67-64-1] from acetic acid [64-19-7] is currendy an important intermediate in the production of acetic acid, acetic anhydride [108-24-7] ethyl acetate [141-78-6] peracetic acid [79-21 -0] pentaerythritol [115-77-5] chloral [302-17-0], glyoxal [107-22-2], aLkylamines, and pyridines. Commercial processes for acetaldehyde production include the oxidation or dehydrogenation of ethanol, the addition of water to acetylene, the partial oxidation of hydrocarbons, and the direct oxidation of ethylene [74-85-1]. In 1989, it was estimated that 28 companies having more than 98% of the wodd s 2.5 megaton per year plant capacity used the Wacker-Hoechst processes for the direct oxidation of ethylene. 

The nameplate capacities for acetaldehyde production for the United States in 1989 are shown in Table 5 (120). Synthetic pyridine derivatives, peracetic acid, acetate esters by the Tischenko route, and pentaerythritol account for 40% of acetaldehyde demand. This sector may show strong growth in some products but all of these materials maybe prepared from alternative processes. 

Table 8.1 shows the stochastic model solution for the petrochemical system. The solution indicated the selection of 22 processes with a slightly different configuration and production capacities from the deterministic case, Table 4.2 in Chapter 4. For example, acetic acid was produced by direct oxidation of n-butylenes instead of the air oxidation of acetaldehyde. Furthermore, ethylene was produced by pyrolysis of ethane instead of steam cracking of ethane-propane (50-50 wt%). These changes, as well as the different production capacities obtained, illustrate the effect of the uncertainty in process yield, raw material and product prices, and lower product... 

Production capacity for acetaldehyde in the United States in 1989 was 443 000 tonnes/ year (Hagemeyer, 1991). Information available in 1995 indicated that it was produced in 16 coimtries (Chemical Information Services, 1995). 

The Wacker process reached a maximum production capacity of 2.6 Mt/a worldwide in the mid 1970 s. The cause of the decline in the following years (1.8 Mt/a in 2003) was the increase in the manufacture of acetic acid (the most important product made from acetaldehyde) by the carbonylation of methanol. In future new processes for chemicals, such as acetic anhydride and alkylamines (which were also made from acetaldehyde) will probably further decrease its importance. With the growing use of syngas as feedstock, the one-step... 

In both processes the aqueous crude aldehyde is concentrated and byproducts are removed in a two-step distillation. Both processes give 94% yields of aldehyde, along with small amounts of 2-chloroethanol, ethyl chloride, acetic acid, chloroacetaldehydes and acetaldehyde condensation products. The Wack-er-Hoechst process currently accounts for 85% of the worldwide production capacity for acetaldehyde. 

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. 

With the permission of the author [3], we borrow here data (Table 1) which indicates the production capacity of the major industrial processes using oxygen for functionalizing hydrocarbons. The production of acetic acid should be added to the list, although 60% of its 6.1 million t/year total world capacity (to reach 67% in the next future) is due to the Monsanto process (methanol carbonylation) [4]. Only the rest (2.4 million t/year) is produced by oxidation of butane or other alkanes or acetaldehyde or, for a small proportion, hy the Showa Denko process (oxidation of ethylene). 

Acetaldehyde production Economic data (France conditions mid-86i Production capacity IQQjOOO t year... 

Table 8.3 gives the main uses of acetaldehyde in 19S4 for Western Europe, the United States and Japan, as well as the production, capacities and consumption for these three geographic areas. 

The worldwide production capacity of acetaldehyde was nearly 3.1.10 t/yewm 1984 and 1986 with the following distribution ... 

The catalytic oxidation of acetaldehyde in the liquid phase to acetic add by air or oxygen is still widely applied, and accounts for about 40 per cent of installed worldwide production capacity. 

The production capacity of acetic add by acetaldehyde oxidation is shrinking as the process became less economic with increasing ethylene prices. Ethylene is needed as the starting material to produce the acetaldehyde applied in the oxidation process. 

About half of the wodd production comes from methanol carbonylation and about one-third from acetaldehyde oxidation. Another tenth of the wodd capacity can be attributed to butane—naphtha Hquid-phase oxidation. Appreciable quantities of acetic acid are recovered from reactions involving peracetic acid. Precise statistics on acetic acid production are compHcated by recycling of acid from cellulose acetate and poly(vinyl alcohol) production. Acetic acid that is by-product from peracetic acid [79-21-0] is normally designated as virgin acid, yet acid from hydrolysis of cellulose acetate or poly(vinyl acetate) is designated recycle acid. Indeterrninate quantities of acetic acid are coproduced with acetic anhydride from coal-based carbon monoxide and unknown amounts are bartered or exchanged between corporations as a device to lessen transport costs. 

Ethyl acetate is an oxygenated solvent widely used in the inks, pharmaceuticals and fragrance sectors. The current global capacity for ethyl acetate is 1.2 million tonnes per annum. BP Chemicals is the world s largest producer of ethyl acetate. Conventional methods for the production of ethyl acetate are either via the liquid phase esterification of acetic acid and ethanol or by the coupling of acetaldehyde also known as the Tischenko reaction. Both of these processes require environmentally unfriendly catalysts (e.g. p-toluenesulphonic acid for the esterification and metal chlorides and strong bases for the Tischenko route). In 1997 BP Chemicals disclosed a new route to produce ethyl acetate directly from the reaction of ethylene with acetic acid using supported heteropoly acids... 

Acetic Acid. Acetic acid is the most important carboxylic acid produced industrially. The annual production in the United States in 1999 was almost 15.7 billion lb. As with many compounds produced on a large scale, acetic acid has several different commercial processes. The carbonylation of methanol is now the dominant route. (This process was described earlier in this chapter in the section Methanol .) The oxidation of acetaldehyde, ethanol, and butane are also important. The percent world capacity for virgin acetic acid... 

Serval reactions occurred evidenced by a complex desorption products. First, acetaldehyde (m/e 29, 15, 44) desorbed at 390 K followed by traces of ethanol at 415 K (2 % of carbon selectivity, table 2). Three other products were observed. Butadiene and butene desorbed at 540 and 673 K respectively with a combined carbon selectivity of 21.1 %. This reaction pathway follows a reductive coupling mechanism which has been observed previously on the surfaces of Ti02 single crystal and powder [19-21]. The formation of C4 olefins is a clear example of the capacity of UO2 surfaces to abstract large amounts of oxygen from surface carbonyls, via pinacolates [19], as follow... 

Until 1992, about 10% of the total acetic acid capacity in the United States was still based on oxidation of acetaldehyde. However, Eastman Chemical, the only domestic producer making acetic acid from acetaldehyde, shut down their unit and put it on standby at that time. As a result, all U.S. production is now by carbonylation of methanol. Some large European producers, such as BP Chemicals, are still using naphtha oxidation for acetic acid, but the amount made by acetaldehyde oxidation is nominal. 

The Wacker process, the oxidation of ethylene to acetaldehyde, lost its original importance over the past 30 years. While at the beginning more than 40 factories with a total capacity of more than 2 million tons of acetaldehyde per year were installed, acetaldehyde as an industrial intermediate was replaced successively by other processes. For example, compounds such as butyraldehyde/butanol are produced by the oxo process from propylene, and acetic acid by the Monsanto process from methanol and CO or by direct oxidation of ethane. The way via acetaldehyde to these products is dependent on the price of ethylene. Petrochemical ethylene from cracking processes became considerably more expensive during these years. Thus, only few factories would be necessary to meet the demand for other derivatives of acetaldehyde such as alkyl amines, pyridines, glyoxal, and pentaerythritol. 

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