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Monsanto/Cativa processes

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) ... [Pg.142]

In 1986, BP Chemicals became the owners of the Monsanto technology. They subsequently also developed their own Cativa process, aimounced in 1996, carbonylation of MeOH to AcOH catalysed by Ir and Mel and promoted with specific metal iodides [8]. As with the improvements in the original Monsanto Rh process, Cativa had benefits such as improved catalyst stability and more favorable operating conditions [9]. [Pg.196]

Interest in iridium-catalyzed methanol carbonylation was rekindled in the 1990 s when BP Chemicals developed and commercialized the Cativa process, which utilizes an iridium/iodide catalyst and a ruthenium promoter. This process has the important advantage that the highest catalytic rates occur at significantly lower water concentration (ca. 5% wt) than for Monsanto s... [Pg.126]

Although the studies at Monsanto indicated that an iodide promoted iridium catalyzed reaction was feasible, much more basic research was needed before a viable commercial procedure (the Cativa process) became possible. [Pg.130]

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. ... [Pg.678]

Although the carbonylation of methanol using an iodide-promoted iridium complex was first reported by Monsanto researchers Roth and Pauhk in 1968, and its mechanism studied by Forster and others, it was the rhodium system that was initially developed for commercialization. A more complex mechanism for iridium, involving both anionic and neutral intermediates was discovered, but it would take over twenty years to coimnercialize an iridium-based system for methanol carbonylation (Scheme 21). In the Cativa process, the iridium complex is promoted by two distinct... [Pg.678]

In addition to rhodium-based catalysts, iridium-based eatalysts have also been developed in a process known as the Cativa process. The iridium system follows a cycle similar to the rhodium system in Figure 14-16, beginning with oxidative addition of j CH3I to [Ir(CO)2l2] The first step in the iridium system is much more rapid than in the Monsanto process and the second step is much slower the second step, involving alkyl . migration, is rate determining for the Cativa process. ... [Pg.540]

In 1996 BP announced the commercialization of their version of a low-water methanol carbonylation technology named Cativa based upon a promoted iridium catalyst. The Cativa process replaced the high-water Monsanto process which had been used by BP. [Pg.107]

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]. [Pg.114]

The Monsanto, E-H, and Cativa processes represent triumphs in the application of organotransition metal chemistry to catalysis, using homogeneous transition metal compounds to promote production of valuable materials cheaply, efficiently, and selectively. Without question, fundamental work accomplished previously on the understanding of basic organometallic reaction types helped... [Pg.366]

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 ]... [Pg.556]

The Monsanto process, which was commercialized in 1970, uses a rhodium catalyst, while the more recent Cativa process uses an iridium one. Iodide complexes and methyl iodide are key players in both processes, and the essential features of the catalytic cycles are the same. The reaction pathways for the rhodium system were elucidated by Forster and have been summarized in several reviews. Maitlis and co-workers have studied the iridium system in detail and the major pathways deduced from a recent study are outlined in the following Scheme ... [Pg.230]

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]. [Pg.276]

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). [Pg.951]

Table 25.3 Comparison of conditions and selectivities of the BASF, Monsanto and Cativa processes for the manufacture of acetic acid (eq. 25.15). Table 25.3 Comparison of conditions and selectivities of the BASF, Monsanto and Cativa processes for the manufacture of acetic acid (eq. 25.15).
A. Haynes (2010) Adv. Catal., vol. 53, p. 1 — Catalytic methanol carbonylation An up-to-date review of the Monsanto and Cativa processes including background information. [Pg.970]

Interestingly, the Cativa process can be realized as a drop-in replacement in plants that have been used beforehand for the rhodium-based Monsanto process, a fact that makes the technology change very attractive for the plant owner. Today, very efficient high capacity production plants based on the Cativa process with capacities of up to 500 000 ta are in commercial operation worldwide. [Pg.747]

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. [Pg.749]

Although rhodium and iridium are high-priced precious metals, their complexes are indispensable for homogeneous catalysis. Prominent examples for their use on the industrial scale are, among others, asymmetric hydrogenation, hydroformyla-tion, and the Monsanto acetic acid or the Cativa process [1]. [Pg.183]


See other pages where Monsanto/Cativa processes is mentioned: [Pg.21]    [Pg.21]    [Pg.265]    [Pg.266]    [Pg.149]    [Pg.216]    [Pg.166]    [Pg.324]    [Pg.117]    [Pg.4]    [Pg.27]    [Pg.6]    [Pg.746]    [Pg.150]    [Pg.22]    [Pg.952]    [Pg.952]    [Pg.739]    [Pg.743]    [Pg.747]    [Pg.120]    [Pg.21]    [Pg.265]    [Pg.266]    [Pg.25]    [Pg.250]    [Pg.333]   
See also in sourсe #XX -- [ Pg.21 ]




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CATIVA process

Cativa

Monsanto

Monsanto process

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