Published January 2003
Lucite (formerly Ineos Acrylics) and Kvaerner have developed a new technology, Alpha, to produce methyl methacrylate (MMA) from ethylene in two reaction steps. The process is claimed to avoid the environmental problems of the conventional acetonecyanohydrin route, which involve handling highly toxic hydrogen cyanide and disposing of large amounts of ammonium bisulfate by-product. In addition, the Alpha technology uses only commodity feedstocks-ethylene is reacted with methanol and carbon monoxide to form methyl propionate, which is then reacted with formaldehyde to yield MMA and water.
Product selectivities in each reaction step are 99.8% and 95%, respectively. Lucite has recently built a fully integrated pilot plant of the process at Teesside, England. Results have been encouraging, with an MMA purity of 99.95% achieved since April of 2002, and an expected lifetime of two years for the catalyst used in the second step. The company has also announced plans to build a worldscale MMA plant in the United States using the technology, with startup scheduled for 2006.
In this review, we present a technical and economic evaluation of the Alpha process, based on the production of 250 million lb/yr (113,400 t/yr) of MMA at a U.S. Gulf Coast location. We conclude that the total fixed capital investment for an MMA plant using the Alpha technology is significantly lower than that required for the same plant using the acetone-cyanohydrin route. The estimated product value for the Alpha process is also very competitive, despite the relatively high energy consumption caused by low per-pass conversion levels in the second reaction step.