PROCESS AND DEVICE FOR PRODUCING A COLOURLESS TRIETHANOLAMINE

摘要

The present invention relates to a process for decolourising triethanolamine (TEA) characterized in that a coloured TEA is exposed to electromagnetic radiation of wavelength chosen within the range from 100 to 1200 nanometres (nm), for a time long enough to reduce the colour of the TEA. The process can be carried out continuously. The invention also related to a process for continuously manufacturing a colourless TEA comprising a step for synthesing TEA by bringing ammonia into contact with ethylene oxide in aqueous medium, a step for separating water and ammonia from a crude TEA comprising TEA as a mixture with other ethanolamines produced during the TEA synthesis, and a step for isolating a purified TEA by distilling the crude TEA. In an additional step, the crude or purified TEA is continuously exposed to the electromagnetic radiation for a time long enough to obtain a colourless TEA. The invention also relates to a device for manufacturing a purified and colourless TEA comprising a reaction zone (A) for synthetising TEA, a zone (B) for separating the crude TEA, a zone (C) for isolating the purified TEA and a zone (D) for storing the purified TEA. The device also comprises at least one radiation zone capable of delivering the electromagnetic radiation, the radiation zone being placed at any point in the device downstream of the zone (B).