TCX integrates with Celanese acetyl platforms. Source: Celanese. Click to enlarge.

Celanese is one of the world’s largest producers of acetyl products (intermediate chemicals, such as acetic acid, for nearly all major industries); acetyl intermediates account for about 45% of Celanese’s total sales. Celanese uses a methanol carbonylation process (reaction of methanol and carbon monoxide); the reaction utilizes a catalyst and the resulting product (acetic acid) is purified through distillation. Celanese continnues to enhance this core technology.

In January of this year, Celanese was awarded a US patent (#7,863,489) on the direct and selective production of ethanol from acetic acid utilizing a platinum/tin catalyst. The patent covers a process for the selective production of ethanol by vapor phase reaction of acetic acid over a hydrogenating catalyst composition to form ethanol. In one embodiment of this invention, the reaction of acetic acid and hydrogen over a platinum/tin catalyst supported on silica, graphite, calcium silicate or silica-alumina selectively produces ethanol in a vapor phase at a temperature of about 250 °C.

Surprisingly, it has now been unexpectedly found that ethanol can be made on an industrial scale directly from acetic acid with very high selectivity and yield. More particularly, this invention provides a process for the selective formation of ethanol from acetic acid comprising: hydrogenating acetic acid over a platinum/tin hydrogenating catalyst in the presence of hydrogen. More specifically, the catalyst suitable for the process of this invention is comprised of a combination of platinum and tin supported on a suitable catalyst support optionally in combination with one or more metal catalysts selected from the group consisting of palladium, rhodium, ruthenium, rhenium, iridium, chromium, copper, molybdenum, tungsten, vanadium and zinc. Suitable catalyst supports include without any limitation, silica, alumina, calcium silicate, carbon, zirconia and titania.

—US Patent 7,863,489

Existing acetyl facilities can be modified and enhanced to produce ethanol through Celanese TCX process, or the TCX facilities can be greenfield. Celanese cites the “breakthrough” elements in its process as the conditions of operation; catalyst systems; materials of construction; and process controls—without getting into much public detail. Synergies with the acetyl business include shared customers, raw materials and the supply chain.

In January, Celanese signed a memorandum of understanding (MOU) with Wison (China) Holding Co., Ltd., a Chinese synthesis gas supplier, for the production of certain feedstocks used in the TCX process. (Earlier post.)

Wison plans to invest in a coal gasification unit to produce syngas per Celanese specs; Celanese will use the output from Wison as feedstock for TCX to produce ethanol for industrial use, and potentially for fuel ethanol.

In the presentation to investors, Celanese executives said that TCX enables the company to produce ethanol at the equivalent of gasoline produced with $60 per barrel crude oil (around $1.50/gallon). Additionally, the company has progressed in its exploration of opportunities to apply TCX technology in fuel ethanol applications through substantive discussions with potential customers.

Celanese on the projected ethanol cost curve in China, based on its internal management estimates, available public information and recent market raw material prices. Source: Celanese. Click to enlarge.

Calling TCX a potential paradigm shift in ethanol production, Celanese said it is targeting China, India, the CIVETS countries (Columbia, Indonesia, Vietnam, Egypt, Turkey and South Africa) and Australia. These regions, the company reasons, are characterized by large and/or growing gasoline demand; are crude oil importers; arable land preservation and food prices are a strategic priority; they want to utilize abundant local resources (natural gas, coal, pet coke) for energy security; and they want to improve tailpipe emissions (smog reduction).

The TCX technology gives Celanese a “clear and sustainable cost curve advantage”, the company says.

For countries such as the EU, Canada and the US, TCX technology could eliminate the need for government subsidies and preferences for liquid fuel feedstock choices, Celanese says.

Celanese has also introduced recent advances in its proprietary AOPlus and VAntage technologies. The company announced AOPlus3, the next generation of its acetic acid technology, which extends its historical technology advantage. Using AOPlus3, the company has the ability to construct a greenfield acetic acid facility with a capacity of 1.8 million tons. VAntage2, its newest vinyl acetate monomer (VAM) technology, could increase capacity by 50% to meet growing customer demand globally. The technology is also expected to enhance production efficiency and lower operating costs. With its strategic optionality, Celanese is focused on maintaining its acetyl leadership position to deliver sustained earnings growth beyond 2013.

The company also announced a new vinyl acetate ethylene (VAE) technology that would increase capacity at existing facilities by the equivalent of a world-scale unit as well as new, low-capital production technology to facilitate growth in emerging regions.

Resources

• Celanese 2011 Investor Day

• US patent 7,863,489: Direct and selective production of ethanol from acetic acid utilizing a platinum/tin catalyst

• Joo, O. S., Jung, K. D., Han, S. H., and Uhm, S. J. (1995) Ethanol and Other Oxygenateds From Low Grade Carbonaceous Resources