Cativa acetic acid process

That said, hio-hased ethanol and ethyl acetate represent a minute fraction of the volume used. The majority of ethanol ntihzed in the lab has been synthesized from the hydrolysis of ethylene, which has been distilled from etude oil. Similarly with ethyl acetate, the acetic acid portion was likely prodnced by the Monsanto (Rhodium) or Cativa (Irridium) acetic acid processes whose feedstock begins with methanol, again originating from crude oil. 

The carbonylation of methanol was developed by Monsanto in the late 1960s. It is a large-scale operation employing a rhodium/iodide catalyst converting methanol and carbon monoxide into acetic acid. An older method involves the same carbonylation reaction carried out with a cobalt catalyst (see Section 9.3.2.4). For many years the Monsanto process has been the most attractive route for the preparation of acetic acid, but in recent years the iridium-based CATIVA process, developed by BP, has come on stream (see Section 9.3.2) ... 

Cativa Not a process but a catalyst for making acetic acid by the carbonylation of methanol. It contains iridium acetate with promoters. Developed by BP Chemicals at Hull, UK and announced in 1996. Used first in Texas City, TX, and planned for use in Malaysia and in Hull. 

In 1970, the first rhodium-based acetic acid production unit went on stream in Texas City, with an annual capacity of 150 000 tons. Since that time, the Monsanto process has formed the basis for most new capacities such that, in 1991, it was responsible for about 55% of the total acetic acid capacity worldwide. In 1986, B.P. Chemicals acquired the exclusive licensing rights to the Monsanto process, and 10 years later announced its own carbonylation iridium/ruthenium/iodide system [7, 8] (Cativa ). Details of this process, from the viewpoint of its reactivity and mechanism, are provided later in this chapter. A comparison will also be made between the iridium- and rhodium-based processes. Notably, as the iridium system is more stable than its rhodium counterpart, a lower water content can be adopted which, in turn, leads to higher reaction rates, a reduced formation of byproducts, and a better yield on CO. 

The major conventional processes for the production of acetic acid include the carbonylation of methanol (originally developed by Monsanto, and now carried out by several companies, such as Celanese-ACID OPTIMIZATION, BP-CATIVA, etc.), the liquid-phase oxidation of acetaldehyde, still carried out by a few companies, and the liquid-phase oxidation of n-butane and naphtha. More recent developments include the gas-phase oxidation of ethylene, developed by Showa Denko K.K., and the liquid-phase oxidation of butenes, developed by Wacker [2a],... 

Cativa A process for making acetic acid by reacting methanol with carbon monoxide (carbonylation). The catalyst contains iridium acetate with promoters. Developed joindy by BP Chemicals, Hull, UK, and the University of Sheffield. First announced in 1996 and installed between 1995 and 1999 in four plants that had been using the former Monsanto acetic acid process. The first plant designed for the process was built by BP Petronas in Malaysia in 2000. A joint venture of BP with Sinopec used the process in a plant expansion in Chongqing, China, in 2005, and planned to build another plant in Nanjing, for completion in 2007. 

The Cativa process was first commercialized in 1995, with the retro-fitting to an existing rhodium-based plant in Texas City (USA), and several other acetic acid plants now use the Cativa technology. 

For approximately 30 years, the most successful industrial process for the carbonylation of methanol relied on an iodide-promoted rhodium catalyst. This technology, originally developed by Monsanto and acquired by BP Chemicals in 1986, is responsible for the majority of the acetic acid synthesized industrially. Since then, the most important development in industrial carbonylation chemistry is the Cativa process, announced by BP Chemicals in 1996. ... 

Since the development of Cativa , BP has converted three world-scale acetic acid plants from the old Rh-based high-water Monsanto technology to the Ir-based low-water process. Significant capital and operating cost savings were achieved from the conversion of a Rh-based process to an Ir-based process. Also, the start-up in 2000 of a 500 X 10 metric ton per year acetic acid plant in Malaysia uses the Cativa process [20d]. 

The latest advance in carbonylation of methanol is the use of an Ir catalyst. Introduced as the Cativa process in 1996 by BP Chemicals, Ir-catalyzed production of acetic acid is now used worldwide.93 The catalytic cycle, called the... 

Acetic acid Ir/I7Ru Cativa -process, BP Chemicals, 1996... 

Jane, J.H. (2001) The Cativa process for the manufacture of acetic acid. Platinum Metals Review, 44,95-105. 

Nowadays, iodine is widely used for the manufacturing of X-ray contrast media, antimicrobial products, as tinctures of polyvinylpyrrolidone-iodine (Povidone-iodine), catalysts in chemical processes (e.g. for the production of acetic acid by carbonylation of methanol in the presence of a rhodium iodide-catalyst (Monsanto process) or an iridium iodide-catalyst (Cativa process)), and also on a smaller scale for the production of pharmaceuticals like thyroid hormones. [ 83 ]... 

As mentioned in Sect. 1, the field of cooperative or synergistic behaviour is very broad and this chapter is certainly not the appropriate place to survey the area. Having said that, mention was made of Jacobsen s quadratic systems in Sect. 2.2.1 although there are some dissimilarities with monometallic CBER. Other groups of reactions which have attracted this author s attention are the Pt-Sn hydroformylation systems and the Ir-Ru Cativa process for acetic acid [87]. A common theme in the Pt-Sn and Ir-Ru systems appears to be the need of the second metal (Sn or Ru) in order to abstract a halogen from the first metal, thereby freeing a coordination site. Catalytic bimetallic systems where a second metal is needed to abstract a halogen should, at some level, exhibit a bilinear term to reflect the abstraction. 

Watson DJ. (1998) The Cativa process for the production of acetic acid. In Herkes FE, editor. Catalysis of organic reactions. Vol. 70. CRC Press, Boca Raton, FL, USA. p 369-380. 

Methanol has been utilized as a practical Cl source in bulk-scale methanol-to-gasoline and methanol-to-olefin processes [120-123], as well as processes for the production of acetic acid, such as the Monsanto and Cativa processes [124—128]. 

Scorpionate or pyrazole V(V) 1-4, 6, 10, and 15, and Re(in) 11, 12, 16, 17, 24-26 complexes have been used as catalysts for the carboxylation of gaseous alkanes via single-pot conversions [5a,fj. These syntheses of carboxylic acids are much simpler than those used in industry. For instance, in the case of the conversion of methane into acetic acid, the current industrial routes commonly involve three distinct stages and use more expensive catalysts and harder experimental conditions (e.g., the Mosanto and BP-Amoco Cativa processes of carbonylation of methanol, at the third stage, are based on Rh and Ir catalysts, respectively) [8b]. 

Around 10 Mt per year of acetic acid are manufactured worldwide and 25% of this is produced using the Cativa process. The reaction ... 

The conversion of MeOH to MeCOjH (eq. 25.15) is carried out on a huge industrial scale, and 60% of the world s acetyls are manufactured using the Monsanto and Cativa processes. Currently, 7 Mt per year of acetic acid are consumed worldwide, with the formation of vinyl acetate (25.15) being the most important commercial end use. Vinyl acetate is the precursor to polyvinylacetate (PVA, 25.16). 

Between 1995 and 2000, BP Chemicals commercialized and began to operate the Cativa process for the production of acetic acid. The catalyst is cz5-[Ir(CO)2l2] in the presence of a ruthenium-based promoter (e.g. Ru(CO)4l2) or an iodide promoter (a molecular iodide, e.g. Inl3). Catalyst... 

Table 25.3 Comparison of conditions and selectivities of the BASF, Monsanto and Cativa processes for the manufacture of acetic acid (eq. 25.15).

Fig. 25.9 The two interrelated catalytic cycles in the Monsanto (M = Rh) and Cativa (M = Ir) acetic acid manufacturing processes.

In the BASF process, methanol and CO are converted in the liquid phase by a homogeneous Co-based catalyst. The reaction takes place in a high-pressure Hastelloy reactor. In recent decades the BASF process has been increasingly replaced by low-pressure alternatives mainly due to lower investment and operating costs. In the low-pressure Monsanto process methanol and CO react continuously in liquid phase in the presence of a Rhl2 catalyst. In 1996, BP developed a new attractive catalyst based on iridium (Cativa process) the oxidative addition of methyl iodide to iridium is 150-times faster than to rhodium. The search for acetic acid production processes with even lower raw material costs has led to attempts to produce acetic acid by ethane oxidation. In the near future ethane oxidation will most likely not compete with methanol carbonylation (even though ethane is a very cheap and attractive raw material) because of the low ethane conversions, product inhibition problems, and a large variety of by-products. 

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