Acetic manufacture

Fig. 1. Flow sheet for methyl acetate manufacture. To convert kPa to psi multiply by 0.145.

Of course, the benefits of microfabricated and stractured reactors are also applicable to even larger scale processes. For example, Evonik s development of a production-scale microstructured reactor for vinyl acetate manufacture (150000t per annum) claims depreciation and operating cost savings of 3 million per year [25]. 

Eastman-Halcon A process for making acetic anhydride from syngas. The basic process is the carbonylation of methyl acetate. Methanol is made directly from the carbon monoxide and hydrogen of syngas. Acetic acid is a byproduct of the cellulose acetate manufacture for which the acetic anhydride is needed. The carbonylation is catalyzed by rhodium chloride and chromium hexacarbonyl. 

Uses In textile dyeing and printing solvent for cellulose acetate manufacturing methylstyrene. 

FIGURE 3 Methyl acetate manufacture from methyl alcohol (methanol). 

Three main routes for vinyl acetate manufacturing are employed today, as follows... 

Figure 10.2 Design of the reactor for vinyl-acetate manufacturing in a recycle system.

Typical Analysis of Cellulose Used for Cellulose Acetate Manufacture ... 

Practically all cellulose acetate manufactured at the present time is the acetone-soluble product, ranging from 37% to 41% acetyl content. Cellulose mixed esters now produced in quantity include cellulose acetate propionate of 33% propionyl content, cellulose acetate butyrate of 16% butyryl content, both of which are used largely for protective coatings and films, and cellulose acetate butyrate of 36% butyryl content used for plastics. 

In contrast to acetaldehyde, where a choice exists between several well-established manufacturing processes, vinyl acetate has been produced until recently by two principal methods—i.e., by the catalytic vapor-phase acylation of acetylene and by the acetalization of acetaldehyde. The new procedure for vinyl acetate manufacture consists of oxidizing ethylene in acetic acid—a process closely related to the Wacker acetaldehyde process. All three manufacturing approaches are outlined in Table XII. 

A recent monograph on cellulose acetates lists more than ten acetate manufacturers worldwide (O Table 9) [83], The industrial process distinguishes several process steps (O Fig. 20). 

Excipient Phenylmercuric acetate Manufacturer Eastman Fine Chemicals Magnification 600 x... 

Ally Acetate can be a starting material for polymers as a comonomer, for glycidyl acetate as a component of epoxy resins, for glycerol, for allyl alcohol by hydrolysis, and for the synthesis of allyl esters of higher acids or other compounds by transesterification or transallylation. Processes for the commercial production of allyl acetate have been developed by Bayer and Hoechst [60], and some Japanese companies. Such processes work in the gas-phase under similar conditions to those used in vinyl acetate manufacture and are currently operated by Showa Denko and Daicel [61]. 

For the latest commercial developments in fluid bed production of vinyl acetate manufacture, see Sect. 6.5.1. 

Fig. 11.2. Vinyl acetate manufacture from ethylene. Bayer/Hoechst and USt Chemicals vapor phase processes. 

A simple example will indicate the scope of the operation and some of its characteristics. Acetic acid is produced by methanol carbonylation or oxidation of acetaldehyde, or as a by-product of cellulose acetate manufacture. In all three cases, a mixture of acetic acid and water must be separated to give glacial acetic acid (99.8 wt%, min). Separation by distillation is expensive because of the need to vaporize large amounts of water with its very high heat of vaporization. Accordingly, an alternative, less expensive liquid-liquid extraction process is often used. 

Vetiver essential oil, to manufacture derivatives like vetiveryl acetate. Manufacturers prefer oil with a high alcohol content. Finding an alternative to vetiver Haitian essential oil, rich in vetiverol, required analyses and a new manufacturing process. 

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