Methanol to acetic acid - Assignment Example

These routes include methyl formate isomerization, methanol carbonylation, synthesis gas to acetic acid, vapor phase oxidization to acetic acid and other novel technologies (Sunley, G., & Watson, D., 2000 p.294). The carbonylation of methanol in the production of acetic acid is capable of catalyzing at high rates with minimal water concentrations while using iridium or iodide based reactor. The onset of methanol carbonylation to acetic acid began in 1960 and was commercialized by the BASF. In this introductory approach, the production o acetic acid employed the use of cobalt catalyst that was in operational synergy with the iodide as a co-catalyst.

This process was conducted at high pressures of about 680 bars as well as high temperatures of 250 degrees Celsius. The Baden Aniline and Soda Factory (BASF) selectivity procedure to acetic acid production accounts for about 90% on the basis of methanol. In the mid 1960s, Monsanto developed a novel approach in methanol carbonylation using rhodium as the major catalyst again aided with iodide as a co-catalyst. This acetic acid production mechanism was highly selective accounting for approximately 99% based upon methanol (Sunley, G.

, & Watson, D., 2000 p.294). The use of rhodium in methanol carbonylation was novel because it allowed acetic acid production under mild chemical environments. . Exclusive licensing and patent rights to Monsanto was acquired by BP Chemicals, the UK based group in 1986. Ten years upon this acquisition, BP Chemicals announced an innovative process in methanol carbonylation. This process was named Cativa™, on the basis of an upgraded iridium/iodide catalyst. The methanol carbonylation process as described by Cativa offers greater improvements compared to the conventional rhodium based catalyst technology.

These advancements include high rates of reaction, improved yield of carbon monoxide, and improved stability of the catalyst enabling the process to be taken under low concentrations of water. Additionally, the Cativa process offers a reduction of the liquid by-products. This full implementation of the Cativa process commercialization was in November 1995 (Sunley, G., & Watson, D., 2000 p.295). The effectiveness of using iridium in tandem with iodide as a co-catalyst for methanol carbonylation at minimal pressure was initially demonstrated by Roth and Paulik while working at Monsanto.

This was during the time of their discovery of the rhodium/iodide catalyst methanol carbonylation process. The reactivity and mechanism of iridium based catalysis in acetic acid production can be conducted in either a nonionic acid or methyl acetate. These studies have elucidated that the iridium catalyzed reaction is more complex compared to rhodium catalysis process (Sunley, G., & Watson, D., 2000 p.296). There exists two catalytic cycles in the iridium catalyzed methanol carbonylation process in the manufacture of acetic acid.

One reaction involves the neutral catalytic intermediaries while the other involves predominant negatively charged species. In his study, Forster was unable to distinguish the reaction rates from the ones