Some Commercially Important Alcohols

Most higher alcohols of commercial importance are primary alcohols secondary alcohols have more limited specialty uses. Detergent range alcohols are apt to be straight chain materials and are made either from natural fats and oils or by petrochemical processes. The plasticizer range alcohols are more likely to be branched chain materials and are made primarily by petrochemical processes. Whereas alcohols made from natural fats and oils are always linear, some petrochemical processes produce linear alcohols and others do not. Industrial manufacturing processes are discussed in Synthetic processes. 

Sodium ethoxide was the first metal alkoxide described in 1837 (1). The alkoxides of many transition metals were developed after World War II (2—5). Today some alkoxides, including those of sodium, potassium, magnesium, aluminum, zirconium, and titanium, are commercially important. The name metal alkoxides is preferred, although metal alcoholates is also used. 

Myrcene Manufacture. An important commercial source for mycene is its manufacture by pyrolysis of p-piaene at 550—600°C (87). The thermal isomerization produces a mixture of about 75—77 wt % myrcene, 9% limonene, a small amount of T -limonene [499-97-8] and some decomposition products and dimers. The cmde mixture is usually used without purification for the production of the important alcohols nerol and geraniol. Myrcene may be purified by distillation but every precaution must be taken to prevent polymerization. The use of inhibitors and distillation at reduced pressures and moderate temperatures is recommended. Storage or shipment of myrcene in any purity should also include the addition of a polymerization inhibitor. 

Alkylphenol ethoxylates (APEO) are no longer used in household detergents in the Western world and represent only a minor portion of the whole non-ionic surfactants group. Even if APEO is a group of surfactants of no commercial importance anymore, there is a need for risk assessment since these compounds are still present in the aquatic environment due to the recalcitrant nature of some of their metabolites (see Chapters 6.1, 6.2.1, 6.3.1 and 6.4). More attention should be given in the future to other non-ionic surfactants like alcohol ethoxylates. 

On the other hand, as production of liquid detergents, either heavy- or light-duty, increases, alcohols with shorter carbon chains become important because of their good liquidities and high solubilities. In fact, this tendency has already appeared in some commercial products. 

The main products are monolitic terpenes such as alpha-terpineol 32. Minor amounts of bicyclic compounds (34), e.g. borneol 31, can be observed. Some of these products are of commercial importance as fragrances with lilac and nutmeg odor (monocyclic alcohols like alpha-terpineol or 1-terpinene-4-ol) or with campher-like and extremely delicate pepper odor (bicyclic compounds). In current industrial practice, the bicyclic alcohol borneol 31 is synthesized by a multi-step procedure. Much research has been done to develop clean processes which have high selectivity towards one of the products starting directly from alpha-pinene 30. 

Syndiotactic polymers, as we have seen above, are stereoregular and so are crystallizable. They, however, do not have the same mechanical properties as isotactic polymers, because the different configurations affect the crystal structures of the polymers. Most highly stereoregular polymers of commercial importance are isotactic, and relatively few syndiotactic polymers are made. Atactic polymers, on the other hand, are usually completely amorphous unless the side group is so small or so polar as to permit some crystallinity. Thus, while atactic poly(vinyl acetate) has never been crystallized, poly(vinyl alcohol), which is derived from it and is also atactic, has been found to crystallize. 

The composition of hpids on the surface of leaves, stems, and fruits is quite different from that of hpids that form intracellular membranes. Their role is the protection of sensitive plant tissues against the loss of water and other biologically important volatiles. Waxes (i.e., esters of FA with monofunctional alcohols) are the most important components of these lipids. Some plant waxes are of commercial importance, such as camauba or candellila wax. They are solid at room temperature and in temperate climates, with the exception of liquid jojoba wax, and are plastic or even liquid in tropical climates. They contain bound saturated long-chain FA and alcohols. Waxes on the surface of apples and other fruits from temperate zones are solids or semisolid pastes, consisting of terpenes, ceryl cerotate, ceryl palmitate, and other esters. In the wax from lettuce leaves, higher alcohols prevail, with only small amounts of free FA (Bakker et al., 1998). Other components, such as alkanes, ketones, esters, secondary alcohols, were detected in other vegetables (e.g., in kale or rutabaga). 

In CZE, serum proteins can be separated also into 5-12 zones using different buffers such as Tris, borate, and tricine, with a pH of 8-11. Serum protein separation can be completed by CE in 2-10 min in contrast to 1-2 h for AG (Figure 2). The correlation coefficient between CE and AG for the separated bands is good. Transferrin isoforms, which are important as marker of alcoholism, have been separated by CZE. Some commercial instruments use multicapillaries of narrow diameter (25 pm) to increase the throughput of the analysis. The narrow capillaries produce better resolution than the wider capillaries with a shorter migration time. 

In the late 1930s, Otto Roelen at Ruhrchemie discovered hydroformylation, sometimes called the 0x0 process, one of the first commercially important reactions to use a homogeneous catalyst. He found that an alkene can be converted to the homologous linear n) and branched iiso) aldehydes (eq. 20) by the addition of H2 and CO, catalyzed by Co2(CO)8 further reduction of the aldehydes to the alcohols is observed under some conditions. Today, 4 million ton of aldehydes are made annually in this way. 

Figure 25.15 shows several familiar commercial products that consist entirely or in large part of an organic alcohol. Let s consider how some of the more important alcohols are formed and used. 

The one- and two-carbon aldehydes, formaldehyde and acetaldehyde, are gaseous products at ambient temperatures. Formaldehyde boils at -2PC while acetaldehyde boils at 20 C. Formaldehyde is most often used as a 37-55 wt% aqueous solution or as an alcoholic solution containing some 55 wt% formaldehyde. Methanol and n-butanol are the two alcohols often used for the formaldehyde solutions. Other aliphatic aldehydes useful as chemical intermediates include propionaldehyde (b.p. 48 C) and two butyl aldehydes, rt-butyraldehyde (b.p. 75"C) and isobutyraldehyde (b.p. 64"C). The one commercially important heterocyclic aldehyde, furfural, is a high boiling-point (161.7 0 liquid. 

Butyl acetate [123-86-4], one of the more important derivatives of -butyl alcohol produced commercially, is employed as a solvent ia rapid dryiag paints and coatings. In some instances, butyl acetate, has replaced ethoxyethyl acetate [111-15-9] due to the latter s reported toxicity and... 

Phenyl-ethyl alcohol, or benzyl carbinol, has been known for many years, but its powerful rose odour has been entirely overlooked, its discovery having been made by an ordinary research chemist and not a perfumery expert. Its preparation was described in the Berichte (9, 373) in 1876, but the product there noted was evidently impure, as its boiling-point is recorded as 212°. Commercial specimens vary greatly in both their odour and their keeping properties, some samples deteriorating in odour very rapidly. It is, therefore, very important to -obtain it in a state of the highest purity. It has the following characters —... 

Not all modified starches are suitable for removal by aqueous dissolution alone. Such modifications of natural starches are carried out to reduce solution viscosity, to improve adhesion and ostensibly to enhance aqueous solubility. Commercial brands vary [169], however, from readily soluble types to those of limited solubility. Indeed, some may be as difficult to dissolve as potato starch if they have been overdried. It is thus very important to be sure of the properties of any modified starch present. If there are any doubts about aqueous dissolution, desizing should be carried out by enzymatic or oxidative treatment. Even if the size polymer is sufficiently soluble, it is important to ensure that the washing-off range is adequate. Whilst the above comments relate to modified starches, other size polymers such as poly(vinyl acetate/alcohol) and acrylic acid copolymers vary from brand to brand with regard to ease of dissolution. 

A number of lower volume chemicals can be obtained from wood hydrolysis. Furfural is formed from the hydrolysis of some polysaccharides to pentoses, followed by dehydration. This process is still used in the Soviet Union. Furfural is used in small amounts in some phenol plastics it is a small minor pesticide and an important commercial solvent. It can be converted into the common solvent tetrahydrofuran (THF) and an important solvent and intermediate in organic synthesis, furfuryl alcohol. 

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