Acetic acid from ethane

Examples for necessary process improvements through catalyst research are the development of one-step processes for a number of bulk products like acetaldehyde and acetic acid (from ethane), phenol (from benzene), acrolein (from propane), or allyl alcohol (from acrolein). For example, allyl alcohol, a chemical which is used in the production of plasticizers, flame resistors and fungicides, can be manufactured via gas-phase acetoxylation of propene in the Hoechst [1] or Bayer process [2], isomerization of propene oxide (BASF-Wyandotte), or by technologies involving the alkaline hydrolysis of allyl chloride (Dow and Shell) thereby producing stoichiometric amounts of unavoidable by-products. However, if there is a catalyst... 

In 1998 scientists at Hoechst reported that the addition of Pd to the MoVNb ethane dehydrogenation catalyst enabled the efficient production of acetic acid from ethane [7]. Doping of this known ethane dehydrogenation catalyst with Pd was probably not random, but predicted on the basis of the classical Wacker catalysis. 

Batch Di (3-pentyl) Malate Process Acetaldehyde from Acetic Acid Ethylene by Oxidative Dehydrogenation of Ethane Butadiene to n-Butyraldehyde and n-Butanol Methacrylic Acid to Methylmethacrylate Coproduction of Ethylene and Acetic Acid from Ethane Methylmethacrylate from Propyne Mixed-C4 Byproduct Upgrade Hydrogen Peroxide Manufacture Di-tem fljy-butyl-peroxide Manufacture Vinyl Acetate Process PM Acetate Manufacture Propoxylated Ethylenediamine Petroleum Products Fuel Additives for Cleaner Emissions Gas Manufacture... 

A-II.1.6 Coproduction of Ethylene and Acetic Acid from Ethane (Bruce Vrana, DuPont, January 2000)... 

Saudi Basic Industries (Sabic) has applied for a patent on a new catalyst which will coproduce ethylene and acetic acid from ethane and air. Their catalyst is a phosphorus-modified molybdenum-niobium vanadate. At different phosphorus levels, the catalyst will produce different ratios of ethylene to acetic acid. Selectivity to the two products is also a function of conversion (i.e., space velocity). As conversion increases, the selectivity to ethylene decreases and the selectivity to acetic acid increases. However, the total selectivity to the useful products decreases as conversion increases. The process runs at higher pressures, about 200 psig, than a conventional ethylene furnace. 

The work was strongly inspired by Union Carbide s Ethoxene process, a route for manufacturing ethylene from ethane and oxygen by oxidative dehydrogenation. The first catalysts consisted of molybdenum, vanadium, and niobium oxides. The selectivity for ethylene was very high but, unfortunately, the conversion of ethane was low ( 10%). Therefore, scientists at the time focused on the co-production of ethylene and acetic acid. A catalyst consisting of molybdenum, vanadium, niobium, calcium, and antimony supported on a molecular sieve was developed (63% selectivity to acetic acid, 14% selectivity to ethylene, and 3% conversion of ethane). In addition, Rhone-Poulenc (catalyst vanadium oxide or vanadyl pyrophosphate) and BP (catalyst combination of rhenium and tungsten) patented processes for the production of acetic acid from ethane. Very efficient catalysts were also disclosed by Hoechst (molybdenum vanadate, promoted with Nb, Sb, Ca, and Pd, 250-280 °C, 15 bar, 86% selectivity to acetic add at 11% conversion of ethane per pass) and Sabic (phosphorus-modified molybdenum-niobium vanadate, 260 °C, 14 bar, 50% selectivity to acetic acid at 53% conversion of ethane). 

Karim, K., Mamedov, E., Al-Hazmi, M., et al. (2001). Catalysts Methods for Producing Acetic Acid from Ethane Oxidation Using Mo, V, Pd and Nb Based Catalysts, Processes of Making Same and Methods of Using Same, US Patent 6,310,241. 

Karim, K., Al-Hazmi, M. and Mamedov, E. (2000). Catalysts for the Oxidation of Ethane to Acetic Acid, Processes of Making Same and Processes of Using Same, US Patent 6,013,597. Karim, K., Mamedov, E., Al-Hazmi, M., et al. (2000). Catalysts for Producing Acetic Acid from Ethane Oxidation, Processes of Making Same and Methods of Using Same, US Patent 6,030,920. Roussel, M., Barama, S., Karim, K., et al. (2009). MoV-based Catalysts in Ethane Oxidation to Acetic Acid Influence of Additives on Redox Chemistry, Catal. Today, 141, pp. 288-293. Fierro, J., Karim, K. and Mamedov, E. (1997). Unpubhshed data. 

CO to generate acetic acid in aqueous conditions by means of several catalysts (Table 2.2).26 RhCl3 catalyzed the direct formation of methanol and acetic acid from methane, CO, and O2 in a mixture of perfluorobutyric acid and water with a turnover rate at approximately 2.9 h-1 based on Rh at 80-85°C.27 Under similar conditions, ethane was more active and gave ethanol, acetic acid, and methanol. 

Of the synthetic reactions of the alkyl halides that with potassium cyanide, which enabled H. Kolbe to synthesise acetic acid from a methane derivative, has already been mentioned (cf. the preparations on pp. 137 and 254). Of the simpler syntheses that of Wiirtz may be mentioned here. Metallic sodium removes the halogen from two molecules and the two radicles combine. Thus, in the simplest case, ethane is formed from methyl bromide ... 

Ethanal is only used as an intermediate to acetic acid and its derivatives and in the near future production of ethanal will be replaced by other routes based on methanol and syn-gas to give acetic acid and acetic anhydride. Vinyl acetate can also be made via syn-gas routes, but the major producer in Europe employs a direct Wacker route with a heterogeneous palladium catalyst (former Hoechst ethene, acetic acid -from syn-gas-, and oxygen). 

Selectivity to acetic acid on the MoVNbPd oxide catalyst was further improved by co-feeding water vapor. As is seen in Fig. 11.2, increasing water vapor concentration in the feed from 0 to 20% enhanced selectivity to acetic acid from 60 to 80% at the expense of selectivities to ethylene and carbon oxides. Overall conversion of ethane practically did not change. 

Acetaldehyde. Until the early 1970s, the maia use of iadustrial ethanol was for the production of acetaldehyde [75-07-0]. By 1977, the ethanol route to acetaldehyde had largely been phased out ia the United States as ethylene and ethane became the preferred feedstocks for acetaldehyde production (286—304). Acetaldehyde usage itself has also changed two primary derivatives of acetaldehyde, acetic acid, and butanol, are now produced from feedstocks other than acetaldehyde. Acetaldehyde is stiU produced from ethanol ia India. 

Selectivity in formation of protective groups may also be achieved by a proper choice of reaction conditions and catalyst. Thus formation of the 3-monothioketal from 3,6-diketones is achieved by dilution of the ethane-dithiol-boron trifluoride reaction mixture with acetic acid. 3-Monocyanohydrins are obtained in good yield from 3,20-diketo-(5a)-pregnanes by diluting the exchange reaction with ethanol. Similarly, dilution of the... 

Aminotrimethanephosphonic acid is formed from formamide, acetamide, urea, or alkanenitriles with phosphorous acid [296]. By reaction of monoalkyl phosphite or P406 with glacial acetic acid or the corresponding anhydride ethane-1 -hydroxy-1,1-diphosphonic acid is formed after hydrolysis [297,298]. P406 can be obtained from P4 and 02 in a high yield of 85-90% [299]. 

The principal competing reactions to ruthenium-catalyzed acetic acid homologation appear to be water-gas shift to C02, hydrocarbon formation (primarily ethane and propane in this case) plus smaller amounts of esterification and the formation of ethyl acetate (see Experimental Section). Unreacted methyl iodide is rarely detected in these crude liquid products. The propionic acid plus higher acid product fractions may be isolated from the used ruthenium catalyst and unreacted acetic acid by distillation in vacuo. 

Acetic acid can be synthesized from methane using an aqueous-phase homogeneous system comprising RhCI as catalyst, CO and 02.17 Side-products included methanol and formic acid, although yields of acetic acid increased upon addition of either Pd/C or iodide ions. The active species is thought to be a CH3-Rh(l) derivative, formed from the C-H activation of methane. The activation of ethane was also achieved, although selectivities were lower, with products including acetic and propionic acids and ethanol (Equation (9)). 

It is important to keep in mind that any extraction of organic matter from soil will include both naturally occurring organic matter and organic contaminants. Separating the two at some later stage of analysis is thus an essential analytical step. For example, extraction of soil with hexane or dichloromethane will extract both l,l,l-trichloro-2,2-di(4-dicholorphenyl)ethane (DDT), a contaminant, and octadecanoic acid, a natural fatty acid. Also, the herbicide 2,4-dichlorophenoxy acetic acid, a contaminant, and indole-3-acetic acid, a natural plant hormone, are both extracted by water (see Figure 12.3). These... 

Other methods for the preparation of acetic acid are partial oxidation of butane, oxidation of ethanal -obtained from Wacker oxidation of ethene-, biooxidation of ethanol for food applications, and we may add the same carbonylation reaction carried out with a cobalt catalyst or an iridium catalyst. The rhodium and iridium catalysts have several distinct advantages over the cobalt catalyst they are much fester and fer more selective. In process terms the higher rate is translated into much lower pressures (the cobalt catalyst is operated by BASF at pressures of 700 bar). For years now the Monsanto process (now owned by BP) has been the most attractive route for the preparation of acetic acid, but in recent years the iridium-based CATTVA process, developed by BP, has come on stream. 

Table 8.1 shows the stochastic model solution for the petrochemical system. The solution indicated the selection of 22 processes with a slightly different configuration and production capacities from the deterministic case, Table 4.2 in Chapter 4. For example, acetic acid was produced by direct oxidation of n-butylenes instead of the air oxidation of acetaldehyde. Furthermore, ethylene was produced by pyrolysis of ethane instead of steam cracking of ethane-propane (50-50 wt%). These changes, as well as the different production capacities obtained, illustrate the effect of the uncertainty in process yield, raw material and product prices, and lower product... 

The submitters employed 75 g. (0.5 mole) of the liquid 1 2 boron trifluoride-acetic acid complex obtained from Harshaw Chemical Company. Since the checkers were unable to obtain this complex from a commercial source, they prepared the solid 1 1 complex following published directions.3 4 A 2-1. threenecked flask is fitted with a mechanical stirrer, a gas outlet tube, and a gas inlet tube extending to the bottom of the flask. A solution of 230 ml. of acetic acid in 750 ml. of 1,2-dichloro-ethane is added to the flask and a stream of boron trifluoride gas is passed through the reaction flask while the solution is stirred and cooled with an ice bath. After approximately 1 hour, when the mixture is saturated, the addition of boron trifluoride is stopped and the insoluble 1 1 boron trifluoride-acetic acid complex is rapidly collected on a filter, washed with 200 ml. of... 

One of the most important challenges in the modern chemical industry is represented by the development of new processes aimed at the exploitation of alternative raw materials, in replacement of technologies that make use of building blocks derived from oil (olefins and aromatics). This has led to a scientific activity devoted to the valorization of natural gas components, through catalytic, environmentally benign processes of transformation (1). Examples include the direct exoenthalpic transformation of methane to methanol, DME or formaldehyde, the oxidation of ethane to acetic acid or its oxychlorination to vinyl chloride, the oxidation of propane to acrylic acid or its ammoxidation to acrylonitrile, the oxidation of isobutane to... 

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