Dormagen, Germany -- Bayer MaterialScience said 16 Jan that it has commissioned a technical centre for developing isocyanate processes. The research centre, at Chempark Dormagen in Germany, was built in just under a year, with an investment of Euro 5 million ($6.34 million).
"All global research activities related to the production of aromatic isocyanates have now been pooled in the new hydrogenation technical centre," said Dr Joachim Wolff, head of Bayer's polyurethanes business, in a company statement. He commented that efficiency gains in research and optimising production processes "will help to further expand our global technological leadership."
The state-of-the-art facility will focus on hydrogenation technology for making precursors to methylene diphenyl diisocyanate (MDI) and toluene diisocyanate (TDI).
MDI is based on benzene, which is first nitrated into nitrobenzene and then hydrogenated to produce aniline. An additional step converts the aniline to diphenylmethane diamine, the direct precursor to MDI.
A catalyst is used to produce aniline from nitrobenzene and hydrogen gas. BMS explains that, with the conventional process, performed at a constant temperature, the substantial heat generated during the reaction must be dissipated using heat transfer oils. The reaction takes place inside a reactor block, in which many thousands of tubes containing the catalyst have been welded together. Finally, the aniline must be painstakingly purified of by-products before it can be used further.
BMS says it has developed an adiabatic variant which is an advance in hydrogenation, eliminating the need for heat transfer and giving a substantial gain in efficiency.
Here the reaction takes place in a large steel vessel, with the catalyst is placed on a grating. The heat of reaction is dissipated together with the gas flow, eliminating the need for a circulating oil loop. The product is also of significantly higher purity.
"The technology is already proving to be extremely successful in our world-scale facility in Shanghai, China," with capacity of 350 kilotonnes per annum. "The conventional process would have been too complex and too expensive for a facility of this size," said Dr Thorsten Dreier, who heads the isocyanate research department at polyurethane production.
Researchers plan to concentrate on optimising both process variants at the new technical centre.
They will also aim to improve the hydrogenation of dinitrotoluene to give toluene diamine, TDI's precursor, and also the Deacon process for the oxidation of hydrogen chloride.
BMS adds that the technical centre building was designed for sustainability using innovative materials from the EcoCommercial Building network.
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