Stilbene optical brighteners are produced at CIBA-GEIGY in the Mclntosh, Alabama, plant. In producing 4, 4’diaminostilbene-2, 2’disulfonic acid, a major intermediate in the production of these brighteners, a large volume of discharges was generated. These discharges were reduced significantly by a number of process improvements consisting of a yield improvement, reducing the volume of an inert non-recoverable solvent and by replacing a Bechamps iron reduction with a catalytic hydrogenation.

You do not currently have access to this content.