Synthesis of vinyl acetate

Scheme 5.1 Synthesis of vinyl acetate alcohol resin (VAAR).

Heterogeneous systems have been developed for the synthesis of vinyl acetate and... 

The industrial synthesis of vinyl acetate [14] via palladium-catalyzed oxidative coupling of acetic acid and ethene using direct 02 reoxidation has already been mentioned (Scheme 3, d). Some NaOAc is required in the reaction medium, and catalysis by Pd clusters, as alternative to Pd(II) salts, was proposed to proceed with altered reaction characteristics [14]. Similarly, the alkenyl ester 37 (Table 5) containing an isolated vinyl group yields the expected enol acetate 38 [55] whereas allylphenol 39 cyclizes to benzofuran 40 with double bond isomerization [56]. 

The case study of the synthesis of vinyl acetate emphasizes the benefits of a systematic design based on the analysis of the reactor/separation/recycles structure. The core of the process is the chemical reactor, whose behavior in recycle depends... 

It is convenient to consider the synthesis of vinyl acetate at this point, because it involves the aerobic oxidation of ethene to the unstable intermediate ethenol (H2C=CH(OH)), followed by its immediate esterification with acetic (ethanoic) acid,... 

Table 8.2 Synthesis of vinyl acetate comparison of palladium and palladium-gold systems.112,114...

Scheme 8.5 Locus of reaction in the synthesis of vinyl acetate.

The application of carbons in catalysis is mainly as support for active phases in various reactions. Besides a wide variety of noble metal-carbon systems for hydrogenation reactions and fuel cell applications, the large-scale application in the synthesis of vinyl acetate and vinyl chloride are important technical applications... 

This type of process is related in principle to those developed by HoechstfWacker to manufacture acetaldehyde (see Section 8X4) by the onee-through oxidation of ethylene by oxygen, in the presence of a redox system, or to produce acetone (Section 1023) from propylene The main reactions involved in the synthesis of vinyl acetate are the following ... 

Synthesis of vinyl acetate acetaldehyde + acetic anhydride = vinyl acetate improved safe process with high yields [21]... 

Each year the United States produces over 2.5 million tons of acetic acid from methanol and carbon monoxide. The primary use of acetic acid is in the synthesis of vinyl acetate, which is used in paints and adhesives. 

In the following discussion the major methods that have been developed for the synthesis of vinyl acetate in particular and vinyl ester monomers in general are described. The oldest process for making vinyl acetate and some of the more volatile vinyl ester monomers is the condensation of acetylene with a carboxylic acid ... 

Depending on the reaction conditions, ethylidine diacetate can be the major product of the metal-catalyzed reaction of acetylene with acetic acid and is also a byproduct of the oxidative acylation of ethylene. In addition, ethylidine diacetate is readily prepared by the reaction of acetaldehyde with acetic anhydride (37). A commercial-scale synthesis of vinyl acetate developed and piloted by the Celenese Corporation involved the pyrolysis of ethylidine diacetate obtained from acetaldehyde (38) [219,220]. 

Abstract In this chapter, an exothermic catalytic reaction process is simulated by using computational mass transfer (CMT) models as presented in Chap. 3. The difference between the simulation in this chapter from those in Chaps. 4,5, and 6 is that chemical reaction is involved. The source term in the species conservation equation represents not only the mass transferred from one phase to the other, but also the mass created or depleted by a chemical reaction. Thus, the application of the CMT model is extended to simulating the chemical reactor. The simulation is carried out on a wall-cooled catalytic reactor for the synthesis of vinyl acetate from acetic acid and acetylene by using both c — Sc model and Reynolds mass flux model. The simulated axial concentration and temperature distributions are in agreement with the experimental measurement. As the distribution of lx shows dissimilarity with Dj and the Sci or Pri are thus varying throughout the reactor. The anisotropic axial and radial turbulent mass transfer diffusivities are predicted where the wavy shape of axial diffusivity D, along the radial direction indicates the important influence of catalysis porosity distribution on the performance of a reactor. 

The reactor simulated is a wall-cooled fixed-bed catalytic reactor reported by Valstar [7] for the synthesis of vinyl acetate from acetic acid and acetylene with zinc acetate on activated carbon as catalyst as given in Sect. 7.1.2. 

The addition of carboxylic acids to terminal acetylenes is catalysed by a RulCaHii)2/PR3/maleic anhydride mixture and gives (34) as the main product.133 This stereochemistry has been exploited in the synthesis of vinyl acetate esters (scheme 41.134 Mixtures of 1- and 2-enol esters result from PhC=CH and RCOOH in the presence of RuCl 3 or Rudll phosphine complexes.136... 

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