Acetylene 1,4-butanediol from

Butanediol is commercially produced by several different processes [7], The most prevalent process for making BDO is known as the Reppe process. This process uses acetylene, generated from natural gas, as its primary feedstock, according to the following ... 

The Reppe process is used to make 1,4-1 butanediol from acetylene. In this process, acetylene and formaldehyde are reacted in the presence of a copper-bismuth catalyst. The resulting intermediate, 2-butyne-l,4-diol is hydrogenated over a Raney nickel catalyst ... 

First there was the chemistry of olefins which owing to Germany s oil deficiency could not be obtained by cracking, but had to be produced by hydrogenation of acetylene originating from coal via calcium carbide. At the beginning of the 1920 s, acetylene was used first for addition reactions at normal pressure the most important product was acetaldehyde which via aldol, 1,3-butanediol, and butadiene led to synthetic rubber. Other important products were ethylene oxide, acrylic esters, styrene, etc. 

The U.S. production of acetylene fell from a peak of 450 kt per annum in the late 1960s, but has recently risen slowly from 130 to 160kt per annum. The largest producers use methane oxidation, with carbide in second place. Some 45% is used for vinyl chloride (to give only 3% of all vinyl chloride produced) the more important use is for 1,4-butanediol (section 12.9.8). 

In the United States butadiene was prepared initially from ethanol and later by cracking four-carbon hydrocarbon streams (see Butadiene). In Germany butadiene was prepared from acetylene via the following steps acetylene — acetaldehyde — 3-hydroxybutyraldehyde — 1,3-butanediol — ... 

Heating butanediol with acetylene in the presence of an acidic mercuric salt gives the cycHc acetal expected from butanediol and acetaldehyde (128). A commercially important reaction is with diisocyanates to form polyurethanes (129) (see Urethane POLYMERS). 

Butanediol. 1,4-Butanediol [110-63-4] made from formaldehyde and acetylene, is a significant market for formaldehyde representing 11% of its demand (115). It is used to produce tetrahydrofuran (THF), which is used for polyurethane elastomers y-butyrolactone, which is used to make various pyrroHdinone derivatives poly(butylene terephthalate) (PBT), which is an engineering plastic and polyurethanes. Formaldehyde growth in the acetylenic chemicals market is threatened by alternative processes to produce 1,4-butanediol not requiring formaldehyde as a raw material (140) (see Acetylene-derived chemicals). 

The principal chemical markets for acetylene at present are its uses in the preparation of vinyl chloride, vinyl acetate, and 1,4-butanediol. Polymers from these monomers reach the consumer in the form of surface coatings (paints, films, sheets, or textiles), containers, pipe, electrical wire insulation, adhesives, and many other products which total biUions of kg. The acetylene routes to these monomers were once dominant but have been largely displaced by newer processes based on olefinic starting materials. 

Much more important is the hydrogenation product of butynediol, 1,4-butanediol [110-63-4]. The intermediate 2-butene-l,4-diol is also commercially available but has found few uses. 1,4-Butanediol, however, is used widely in polyurethanes and is of increasing interest for the preparation of thermoplastic polyesters, especially the terephthalate. Butanediol is also used as the starting material for a further series of chemicals including tetrahydrofuran, y-butyrolactone, 2-pyrrohdinone, A/-methylpyrrohdinone, and A/-vinylpyrrohdinone (see Acetylene-DERIVED chemicals). The 1,4-butanediol market essentially represents the only growing demand for acetylene as a feedstock. This demand is reported (34) as growing from 54,000 metric tons of acetylene in 1989 to a projected level of 88,000 metric tons in 1994. 

Growth in the use of acetylene for the production of 1,4-butanediol is projected to continue at the rate of about 5% per year. However, competition from a new technology based on maleic anhydride may impact the use of acetylene in this market. 

Apart from lactic and hydroxyacetic acids, other a- and P-hydroxy acids have been small-volume specialty products produced in a variety of methods for specialized uses. y-Butyrolactone [96 8-0] which is the monomeric inner ester of y-hydroxybutyric acid [591-81-17, is a large-volume chemical derived from 1,4-butanediol (see Acetylene-derived chemicals). 

Diol Components. Ethylene glycol (ethane 1,2-diol) is made from ethylene by direct air oxidation to ethylene oxide and ring opening with water to give 1,2-diol (40) (see Glycols). Butane-1,4-diol is stiU made by the Reppe process acetylene reacts with formaldehyde in the presence of catalyst to give 2-butyne-l,4-diol which is hydrogenated to butanediol (see Acetylene-DERIVED chemicals). The ethynylation step depends on a special cuprous... 

The pattern of commercial production of 1,3-butadiene parallels the overall development of the petrochemical industry. Since its discovery via pyrolysis of various organic materials, butadiene has been manufactured from acetylene as weU as ethanol, both via butanediols (1,3- and 1,4-) as intermediates (see Acetylene-DERIVED chemicals). On a global basis, the importance of these processes has decreased substantially because of the increasing production of butadiene from petroleum sources. China and India stiU convert ethanol to butadiene using the two-step process while Poland and the former USSR use a one-step process (229,230). In the past butadiene also was produced by the dehydrogenation of / -butane and oxydehydrogenation of / -butenes. However, butadiene is now primarily produced as a by-product in the steam cracking of hydrocarbon streams to produce ethylene. Except under market dislocation situations, butadiene is almost exclusively manufactured by this process in the United States, Western Europe, and Japan. 

Chemicals. Although the amount of butylenes produced ia the United States is roughly equal to the amounts of ethylene and propylene produced, the amount consumed for chemical use is considerably less. Thus, as shown ia Table 10, the utilisation of either ethylene or propylene for each of at least five principal chemical derivatives is about the same or greater than the utilisa tion of butenes for butadiene, their main use. This production is only about one-third of the total the two-thirds is derived directiy from butane. The undedyiag reasons are poorer price—performance compared to derivatives of ethylene and propylene and the lack of appHcations of butylene derivatives. Some of the products are more easily derived from 1-, 2-, and 3-carbon atom species, eg, butanol, 1,4-butanediol, and isobutyl alcohol (see Acetylene-DERIVED chemicals Butyl alcohols). 

The hydroformylation of acrolein cyclic acetals has received considerable attention in the recent patent literature as a route to 1,4-butanediol (76-52). This diol is a comonomer for the production of polybutylene terephthalate, an engineering thermoplastic. The standard method for its manufacture has been from acetylene and formaldehyde, as shown in Eqs. (37) and (38) ... 

The most recent entrant-to the. club of commodity chemicals is 1,4-butanediol (BDO), a petrochemical used in some of the more specialized applications such as chemical intermediates for the production of tetrahydro-furane and gama-butyrolactone, polybutylene terephthalate, and the more familiar polyurethanes. Traditionally, the Reppe process was the primary route to BDO, based bn acetylene and formaldehyde feeds. More recently, the share of BDO from butane and propylene oxide based production has grown rapidly. 

Butanediol, also known as tetramethylene glycol, is produced by the hydrogenation of butynediol (made from acetylene and formaldehyde). 

PEROXIDES AND PEROXIDE COMPOUNDS - ORGANIC PEROXIDES] (Vol 18) -from butanediol [ACETYLENE-DERIVED CHEMICALS] (Vol 1)... 

Butanediol. In 2000, 164 million lb of 1,4-butanediol were made from acetylene in the United States. It is the largest consumer of acetylene. 

This consists in causing formaldehyde to react with acetylene in the presence of a copper-based catalyst The ethynybtian reaction yields 1,4-butynediol and a few per cent of propargyl alcohol resulting from the condensation of a single molecule of formaldehyde. The 1,4-butynediol is hydrogenated to 1,4-butanediol in a second step. 

Now, THF is produced by selective hydrogenation of maleic anhydride [6, 7] or by dehydration of 1,4 butanediol (resulting from acetylene and formaldehyde, followed by the hydrogenation of the resulting 2-butyne-l,4 diol [23]). The old technology based on furfurol may be reconsidered in the future, because it uses a renewable resource as its raw material. 

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