Ethylene hydroformylation

The catalyst formed in this manner exhibited carbonyl infrared absorptions, as shown in Table XXX. These catalysts were tested by hydroformylation of ethylene or propylene at 100°C and atmospheric pressure. Both were effective, with (A) being better than (B), probably because of the higher surface area. The aldehyde formed from propylene was a mixture of 63% n- and 37% isobutyraldehyde. The rate expression for ethylene hydroformylation was ... 

C02(C0)s ZnO Adsorption from solution and vacuum treatment Ion-pairing species stable up to 160°C under CO/H2 high selectivity to C1-C3 alcohols in CO hydrogenation, performance in ethylene hydroformylation [139]... 

RhCo3(CO)i2 SiOj Adsorption from solution and thermal treatment under hydrogen RhCo3 entities, highly active in ethylene hydroformylation [141]... 

Bimetallic supported Co-Rh catalysts are very active towards the ethanol synthesis from CO and very effective in ethylene hydroformylation to C3 oxygenates (n-propanal and n-propanol). 

Ethylene hydroformylation was treated as a separate case, as difSculties arise from dramatic changes in the IR spectrum of dissolved ethylene as a function of its partial pressure. This was overcome using the method of band-target entropy minimisation (BTEM, see Chapter 4) to recover the pure component spectra of all observable species and their concentrations [72]. As well as the conventional acyl tetra-carbonyl, [Rh(C(0)Et)(C0)4], evidence was obtained for [Rh(C(0)Et)(C0)3(C2H4)], containing coordinated ethylene. The presence of this species indicates that ethylene can compete with H2 for the unsaturated [Rh(C(0)Et)(C0)3]. The ketone and polyketone side products of Rh-catalysed ethylene hydroformylation arise from insertion of coordinated ethylene into the Rh-acyl bond in [Rh(C(0)Et)(C0)3(C2H4) ... 

Table 8. Face of the unsaturated prochiral carbon atom which originates the predominant enantiomer in 1,1-disubstituted ethylenes hydroformylation...

In ethylene hydroformylation with RhH(CO)(PPh3)3, after several hours of reaction a material containing C, H, and P is isolated that has NMR signals at H (31P) 7.06 and a triplet and quartet between 0 and 36. What is the material, and how is it formed ... 

Kim and Datta [1991] tested the above concept with the homogeneously catalyzed ethylene hydroformylation by hydridocarbonyltris (triphenyl phosphine) Rh (I) catalyst dissolved in dioctyl phthalate solvent. They concluded that for effective separation of the product, the transport resistance of the catalyst layer should be less than that for the membranes by controlling the liquid loading of the catalyst layer. They also pointed out that the organic membranes used can not withstand the aggressive reaction conditions and suggested that ceramic membranes appear to hold promises for practical applications. 

Two recent studies of ethylene hydroformylation over Mn-Rh/Si02 at 240°C and atmospheric pressure have appeared 260,261). The results have been simulated by elementary-step models with Eqs. (2)-(4). Isotopic and IR studies have been performed on the responses to input pulses. 

Accounting for a share of about 73 % of total production capacity, C4 products have firmly established their leading position in this field. Ethylene hydroformylation to propanal amounts to 2-3 % of the hydroformylation capacity for C4 products and is only of minor importance. The hydroformylation of olefins of medium chain length, predominantly in the Cg/Cg range (diisobutene, propene trimer), makes up around 20 % of the total production capacity. Only about 6 % of the total production capacity is used to hydroformylate higher olefins. 

Back in 1974, Celanese (later Hoechst Celanese) started the production of bu-tanals by a process [192] which closely resembles the LPO one subsequently (1976) established by UCC. It is an open question which of the two companies was the really first to introduce low-pressure hydroformylation, as UCC claims to have run an ethylene hydroformylation unit at Ponce before the start-up of the propene unit at the same site [222]. There are only minor differences if any, between the Celanese and the UCC process [192]. 

A third homogeneously catalyzed process, on the basis of formaldehyde condensation with propanal to give methacrolein and subsequent oxidation to methacrylic acid, was commercialized in 1990 by BASF. Application of this process is limited by the availability of cheap propanal, produced by large-scale ethylene hydroformylation (cf. Section 2.1.1). 

The water-soluble cluster Ru3(CO)9(tppms)3 (tppms = sodium diphenylphosphinobenzene-w-sulfonate) was used as the catalyst precursor for hydrogenation of acrylic acid and styrene. The cluster also catalyzed the hydroformyla-tion of propylene with syngas in water, forming mainly butanal, along with smaller amounts of 2-methylpropanal, butanol, and 2-methylpropanol. Typical conditions were 393 K and 40 atm of 1 1 CO H2. TOFs of 61 mol products (mol cluster h) and product n iso ratio of 15.9 were obtained. Ethylene hydroformylation was also examined. 

The heterogeneous catalyst derived from [TMBA]2[FeIr4(CO)i5] on Si02 had better alcohol selectivity in ethylene hydroformylation than [Ir4] on Si02. ° ... 

Heterogeneous [FeePde] catalysts on Si02 had enhanced alcohol selectivity in ethylene hydroformylation compared to PdCl2. The [Fe4Pd] catalyst led to an even higher selectivity in alcohol, because of its higher Fe contentJ Propylene hydroformylation was also catalyzed by these bimetallic systems. 

Yamagishi T, Ito S, Tomishige K, Kunimori K (2005) Selective formation of 1-propanol via ethylene hydroformylation over the catalyst originated from RhV04. Catal Commun 6 421 25... 

The mechanism of ethylene hydroformylation has been studied by DFT calculations with the PBE gradient correlation and the TZ2p basis set, using organoplatinum hydrides [[(R2PO)2H]Pt(PR3)(H)] (R = H, Me, CF3) as a model system. Insertion into the Pt-Et CT-bond has been identified as the rate-limiting step (RLS). ... 

In this area, Yang and colleagues have designed a bilayer stracture by combining platinum and cerium oxide nanocube into sub-lOnm layers on silica substrate [7]. Two distinct reactions can be utilized on a bilayer structure with two metal-metal oxide interfaces (CeO -Pt and Pt-SiO ). The CeO -Pt interface is used to catalyze the decomposition of methanol into CO and H, while ethylene hydroformylation happens on the Pt-SiO interface. This is an intriguing concept on making nanocrystal bilayer structures designed for the application of multifunctional catalysts, the so-called tandem catalyst. 

Figure 3.3 Ethylene hydroformylation with MeOH over a tandem catalyst. (Derived from Ref. [36].)...

Olefin and synthesis gas are fed to the reactor separately. However, in special cases such as ethylene hydroformylation they may be fed through one line. Solvents are generally not used in technical operations. Synthesis... 

Among the propanols, isopropanol is of higher technical relevance. The compound is obtained in a very similar way to ethanol by acidic hydratization (direct or indirect) of propene [route (c) in Topic 5.3.1]. n-Propanol is obtained from ethylene hydroformylation, followed by hydrogenation of the intermediate propanal. 

Our group studied ethylene hydroformylation catalyzed by HRh(CO)(TPPTS)3 in an aqueous-organic biphasic catalytic system, and successfully applied it in the industrial productionin Nanjing, China. The current capacity is 20 000 tons per year. 

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