Chemistry

Dye and product desalination

FarbstoffabtrennungMembrane filtration plants of OSMO Membrane Systems GmbH offer various solutions for desalination. Hereby, we offer all stages of projecting – from proof of concept to costumized plant – from a single source.

In times of increasing energy and raw material costs, desalination can be a remarkable contribution in the process chain, to cut running costs and to conserve resources.

At the production of dyes, e.g. azo dyes, optical brightening agents (OBA) and so on, nano filtration plants are used for retention of pigments and elution of the present neutral salts (Na+Cl-). At the first production step, the content of sodium chloride will be reduced by dia filtration and addition of deionized water until the required salinity of permeate is reached. The proper selection of the NF membrane achieves the highest possible dye retention at the remaining NF concentrate. After this step, dye can be concentrated to the required values. So, different steps of production can be realized by only one nano filtration plant. Depending on the type of dye and the required retention rate, different NF membranes are suitable.

Other organic solutions can be desalinated in an analogous way with nanofiltration.