Alcohols linear

Linear alcohols (C12-C26) are important chemicals for producing various compounds such as plasticizers, detergents, and solvents. The production of linear alcohols by the hydroformylation (Oxo reaction) of alpha olefins followed by hydrogenation is discussed in Chapter 5. They are also produced by the oligomerization of ethylene using aluminum alkyls (Ziegler catalysts). 

In the next step, ethylene is polymerized by the action of triethylaluminum at approximately 120°C and 130 atmospheres to trialkylalu-minum. Typical reaction time is approximately 140 minutes for an average C12 alcohol production  

The oxidation of triethylaluminum is carried out between 20-50°C with bone dry air to aluminum trialkoxides. 

The final step is the hydrolysis of the trialkoxides with water to the corresponding even-numbered primary alcohols. Alumina is coproduced and is characterized by its high activity and purity  

A new process developed by Institut Francais du Petrole produces butene-1 (1-butene) by dimerizing ethylene.A homogeneous catalyst system based on a titanium complex is used. The reaction is a concerted coupling of two molecules on a titanium atom, affording a titanium (IV) cyclic compound, which then decomposes to butene-1 by an intramolecular (3-hydrogen transfer reaction.  

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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. 

Plasticizer Range Alcohols. Commercial products from the family of 6—11 carbon alcohols that make up the plasticizer range are available both as commercially pure single carbon chain materials and as complex isomeric mixtures. Commercial descriptions of plasticizer range alcohols are rather confusing, but in general a commercially pure material is called "-anol," and the mixtures are called "-yl alcohol" or "iso...yl alcohol." For example, 2-ethyIhexanol [104-76-7] and 4-methyl-2-pentanol [108-11-2] are single materials whereas isooctyl alcohol [68526-83-0] is a complex mixture of branched hexanols and heptanols. Another commercial product contains linear alcohols of mixed 6-, 8-, and 10-carbon chains. 

Most manufacturers sell a portion of their alcohol product on the merchant market, retaining a portion for internal use, typically for the manufacture of plasticizers. Sterling Chemicals linear alcohol of 7, 9, and 11 carbons is all used captively. Plasticizer range linear alcohols derived from natural fats and oils, for instance, octanol and decanol derived from coconut oil and 2-octanol derived from castor oil, are of only minor importance in the marketplace. 

Some 2,000—3,000 t/yr of these specialty alcohols are produced ia the United States (Exxon) and ia Germany (Henkel) (28). Their high Hquidity because of branching permits use of less volatile, higher molecular weight materials, reported to be less irritating than the lower molecular weight linear alcohol materials, ia a variety of cosmetic products (29). 

Sterling Chemicals, Inc. (Texas City, Tex.) Cy, C9, C linear alcohols 102 Co... 

The spectmm of oxo products ia Japan is far less diverse. Nearly 75% of Japan s total oxo capacity of 733,000 t is dedicated to the hydroformylation of propylene. 2-EH derived from -butyraldehyde is by far the dominant product. Other products iaclude linear alcohols and higher branched alcohols. Additionally, Japan is the world s principal source of branched heptyl alcohol. The three ptincipal Japanese oxo producers having slightly more than 70% of Japan s total oxo capacity are Mitsubishi Kasei, Kyowa Yuka, and Japan Oxocol. 

Primary Amyl Alcohols. Primary amyl alcohols (qv) are manufactured by hydroformylation of mixed butenes, followed by dehydrogenation (114). Both 1-butene and 2-butene yield the same product though in slightly different ratios depending on the catalyst and conditions. Some catalyst and conditions produce the alcohols in a single step. By modifying the catalyst, typically a cobalt carbonyl, with phosphoms derivatives, such as tri( -butyl)phosphine, the linear alcohol can be the principal product from 1-butene. 

Until comparatively recently the bulk of general purpose phthaiate plasticisers have been based on the branched alcohols because of low cost of such raw material. Suitable linear alcohols at comparative prices have become available from petroleum refineries and good all-round plasticisers are produced with the additional advantage of conferring good low-temperature flexibility and high room temperature resistance to plasticised PVC compounds. A typical material (Pliabrac 810) is prepared from a blend of straight chain octyl and decyl alcohols. 

The reaction between ethylene oxide and long-chain fatty alcohols or fatty acids is called ethoxylation. Ethoxylation of C10-C14 linear alcohols and linear alkylphenols produces nonionic detergents. The reaction with alcohols could be represented as ... 

Linear alcohols used for the production of ethoxylates are produced by the oligomerization of ethylene using Ziegler catalysts or by the Oxo reaction using alpha olefins. 

Oligomerization of ethylene using a Ziegler catalyst produces unbranched alpha olefins in the C12-C16 range by an insertion mechanism. A similar reaction using triethylaluminum produces linear alcohols for the production of biodegradable detergents. 

Alcohols obtained from fats and oils contain an even number of carbon atoms and they are completely linear. Alcohols obtained from petrochemical sources can be linear or branched, depending on the manufacturing process, and can also have even or odd numbers of carbon atoms. In many practical applications the small differences observed in the behavior of sulfated alcohols or indeed sulfated alcohol ethoxylates from either source is of no significance and the choice is made on economic grounds. 

The Ziegler process produces linear alcohols with an even number of carbon atoms and is based on the polymerization of ethylene under catalytic conditions, generally with triethylaluminum as in the Alfol and the Ethyl processes. The distribution of alkyl chains depends on the version of the process employed but the alcohols obtained after fractionation can be equivalent to those obtained from fats and oils or have purpose-made distributions depending on the fractionation conditions. 

The rheology and phase behavior of sodium linear C16-C18 alcohol sulfate and sodium oxo C14-Cl5 (80% linear) alcohol sulfate was studied by van Zon et al. [75]. The oxoalcohol sulfate can be prepared as a handleable 65-70% concentrate. The linear C16-C18 alcohol sulfate only allows 55-60% as maximum concentration. The hexagonal phase of the oxoalcohol sulfate extends from 38% to 55% active matter whereas the hexagonal band of the linear alcohol sulfate is very narrow, only extending from 35% to 40% and its crystallization line is situated at a higher level than for the oxo derivative. 

The foaming properties of sodium symmetrical secondary alcohol sulfates, sodium secondary alcohol sulfates, isomeric sodium secondary pentanol sulfates, and sodium linear alcohol sulfates were studied by Dreger et al. [72] via the Ross-Miles test [150] at 46°C. Within the linear series sodium tetradecyl sulfate produces the largest amount of foam. The influence of several electrolytes was also studied. 

TABLE 32 Primary Biodegradation of Linear Alcohol Sulfates... 

However, they behave similarly to alcohol sulfates since linear alcohol ether sulfates are more easily biodegradable than branched alcohol ether sulfates. Also linear secondary alcohol ether sulfates are poorer than linear primary alcohol ether sulfates [425]. 

Steinle et al. [426] studied the primary biodegradation of different surfactants containing ethylene oxide, such as sulfates of linear primary alcohols, primary oxoalcohols, secondary alcohols, and primary and secondary alkyl-phenols, as well as sulfates of all these alcohols and alkylphenols with different degrees of ethoxylation. Their results confirm that primary linear alcohol sulfates are slightly more readily biodegradable than primary oxoalcohol sulfates and that secondary alcohol sulfates are also somewhat worse than the corresponding linear primary. 

Figure 7. Dependence of the fluorescence quamum yield of BMPC on solvent viscosity ( ) in linear alcohols, from methanol to dccanol, at 25°C, (o) in absolute ethanol between 200 and 298 K. The quantum yields were measured on optically thin samples (Am <0.2). The value in ethanol, 5.7x10, was determined relative to quinine sulfate in 0.5 mol 1" HjSO ((j)p=0.55 [62]) and 9,10-diphenylanthracene in cyclohexane (4ip=0.90 [63]). It was then used as a reference for the determinations in the other alcohols.

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