Hydroformylated oils

An important application for hydroformylated oils and fats is the production of polyurethanes. Hydroformylated fatty acids are hydrogenated to the corresponding diols and then converted to polyurethanes with diphenylmethane diisocyanate (Scheme 11). The polymer has a glass transition temperature of —33°C to —56°C, and the molecular weight is between 1,000 and 4,000 [12]. 

Three significant, commercial processes for the production of amyl alcohols include separation from fusel oils, chlorination of C-5 alkanes with subsequent hydrolysis to produce a mixture of seven of the eight isomers (Pennsalt) (91), and a low pressure 0x0 process, or hydroformylation, of C-4 olefins followed by hydrogenation of the resultant C-5 aldehydes. 

The octylphenol condensate is used as an additive to lubricating oils and surface-active agents. Other uses of dimer are amination to octylamine and octyldiphenylamine, used in mbber processing hydroformylation to nonyl alcohol for phthalate production and carboxylation via Koch synthesis to yield acids in formulating paint driers (see Drying). 

Synthesis gas is an important intermediate. The mixture of carbon monoxide and hydrogen is used for producing methanol. It is also used to synthesize a wide variety of hydrocarbons ranging from gases to naphtha to gas oil using Fischer Tropsch technology. This process may offer an alternative future route for obtaining olefins and chemicals. The hydroformylation reaction (Oxo synthesis) is based on the reaction of synthesis gas with olefins for the production of Oxo aldehydes and alcohols (Chapters 5, 7, and 8). 

Higher molecular primary unbranched or low-branched alcohols are used not only for the synthesis of nonionic but also of anionic surfactants, like fatty alcohol sulfates or ether sulfates. These alcohols are produced by catalytic high-pressure hydrogenation of the methyl esters of fatty acids, obtained by a transesterification reaction of fats or fatty oils with methanol or by different procedures, like hydroformylation or the Alfol process, starting from petroleum chemical raw materials. 

The desire to minimize this competitive oligomerization has motivated research into alternative means to decrease the polydispersity and simultaneously increase the molecular weight of the seed-oil derived polyols. Recent patents [128, 129] investigate an approach previously demonstrated for the hydroformylated polyols [130-132], i.e., hydroxylation of the fatty acid alkyl ester followed by polymerization from a petrochemically derived initiator molecule. Inventors state that this approach provides an improvement over previous epoxidized/hydroxylated polyols by allowing better control of the molecular weight and the functionality of the polyol products. 

Hydroformylation is the process of coupling carbon monoxide to an olefin with a reductive catalyst and hydrogen to produce an aldehyde-functionalized substrate. This coupling is typically followed by hydrogenation to produce a primary hydroxyl group. Several academic and commercial programs have participated in the development of hydroformylated triglycerides and fatty acid derivatives for use in polyurethanes. Two main processes for the hydroformylation of seed oils have been utilized. 

The hydrogenation step following hydroformylation serves two important purposes. It reduces the aldehyde intermediate product to the desired primary alcohol functional group, which is the primary site of reactivity of the polyol with isocyanates. It also reduces the residual olefins in the FAMEs to saturated hydrocarbons, thus eliminating the pathway to Hock degradation and odor development, which is inherent to other processes that leave fatty acid unsaturation in the polyols. This step eliminates the typical vegetable oil odor from the final namral oil polyols of this process. 

Fig. 22 Respirometry of vegetable oil-based polyurethanes made from the following polyols triolein-met arrowhead), soy-HF (filled square), soy-met 180 (open diamond), soy-met 206 (open circle), and linseed met (open square). Also shown is ESO/BF3 polymer (open triangle) and soybean oil control (filled circle). Temperature was increased from 30°C to 55°C on day 71. Note that hydroxyl number of 180 has the functionality of 3.3 and that of hydroxyl 206 is 4.0. Met refers to polyol made from ESO and methanol HF refers to polyol from hydroformylation and reduced ESO. Reproduced from [152] by permission of Journal of Polymers and the Environment...

It is reasonable to assume that prior to the exclusive use of chemicals derived from feedstocks other than crude oil, chemicals based on crude oil and chemicals based on alternate feedstocks will supplement each other. This situation has already arisen as is exemplified in the use of coal derived CO/H2 to hydroformylate olefins originating from mineral oil. For instance, in West-Germany Hoechst converts coal into CO/H2 which is used to prepare alcohols from naphtha derived olefins. Table IV summarizes a number of additional reactions in which this point is especially emphasized. 

An improved two-cycle oil is a combination of poly(isobutylene) amine and a nitrogen containing dispersant (70). Poly(isobutylene) amine can be prepared by chlorination or hydroformylation of PIB, and subsequent amination with ethylene diamine or similar compounds. Eventually, poly(alkyleneamine)s are obtained by these procedures. These compounds are added in amounts of 6-7%. A two-cycle engine lubricating oil composition has typically a composition as given in Table 6.6. 

Examples of catalytic reactions and processes relevant to hydrocarbon chemistry are numerous. The technologies of the oil refinery with extremely low (<0.1) E factors are excellent examples demonstrating the possibilities that can be achieved by the development of selective catalytic methods, particularly by the use of various solid acids (see detailed discussions in Chapter 2). Further examples of commercially highly successful processes are the oxidation catalyst TS-1 developed by Enichem researchers160 161 (see Sections 9.1.1, 9.2.1, and 9.4.1), the homogeneous aqueous-phase Rh-catalyzed hydroformylation (see Sections 7.1.3 and 7.4.1), and single-site metallocene polymerization catalysts, which allow the preparation of tailored polymers with new properties (see Sections 13.3.2).162-164... 

Hydrogenation Hydroformylation 100-300 edible oils hydrogasification hydrocracking desulfurization catalytic cracking naphtha hydroforming coal liquefaction fatty alcohols 1-6-hexanediol 1-4-butanediol hexamethylenedi amine C4 to Cl5 products... 

Triglycerides and technical-grade fatty acid esters can be used as the starting material in hydroformylation (Scheme 7). Soybean oil and technical-grade methyl oleate were hydroformylated by [RhH(CO)2PPh3)] with triphenylphosphine as the ligand. 

A quantitative conversion has been described within 4 h with 40 bar of pressure and at 100°C. The polyunsaturated fatty acids like linoleic acid were hydroformylated manifold. If RhC P O is employed, soybean oil cannot be hydroformylated because only the isomerization of conjugated fatty acids is obtained [24]. The direct processing of a fat without cleavage of the triglyceride is attractive for several applications. 

Several oleocompounds were tested in hydroformylation with Rh(CO)2acac in toluene with triphenylphosphine. Soybean oil, high oleic sunflower oil, safflower oil, and linseed oil were employed at concentrations up to 6.53 mol L 1. With... 

A kinetic study of the hydroformylation of soybean oil was undertaken by Kandanarachchi [25] the pressure was varied between 40 and 110 bar, and the conversion rate increased with the pressure. The activation energy was calculated both for a rhodium system with (PhO)3P and with (Ph)3P showing that the phosphine species has a lower activation energy. Also, the temperature effect was studied, and it was found that the reaction rate increased until 100°C. Above that, the high temperature apparently inhibited the reaction due to phosphido-bridged clusters which are favored at higher temperatures. 

Other Cig-fatty acids have also a high potential in hydroformylation, such as ricinoleic acid, which contains an additional hydroxy group at position 12 of the fatty carbon chain and which is not food relevant [26], The hydroformylation of ethyl ricinoleate, derived from castor oil, shows selectivity for cyclization of the carbon chain because of the reaction of the hydroxyl group with the formyl group (Scheme 8). 

Dow also developed polyurethane foams from polyols via hydroformylation of fatty acids. The foams have properties which are comparable to foams from petrochemicals in terms of density and flexibility. The advantages of using sustainable feedstocks in viscoelastic foams are increased load bearings and tensile and tear properties [39, 40]. The hydroformylation and consecutive hydrogenation of fatty acids derived from seed oil can also be used to form low viscosity polyester polyols. Therefore, fatty acid methyl esters are transesterified with diols, e.g., glycol (Scheme 12). The polymer contains chemically active hydroxy groups which can be used for polyurethanes in coating applications [41]. 

Petrovic ZS, Cvetkovic I, Hong DP, Wan X, Zhang W, Abraham TW, Malsam J (2009) Vegetable oil-based triols from hydroformylated fatty acids and polyurethane elastomers. Eur J Lipid Sci Technol 112 97-102. doi 10.1002/ejlt.200900087... 

Frankel EN, Metlin S, Rohwedder WK, Wender I (1969) Hydroformylation of unsaturated fatty esters. J Am Oil Chem Soc 46 133-138. doi 10.1007/bf02635716... 

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