I was wondering whether the term 'bicromatic' isn't derived from ' chromatografic'. "Chromatography is the process of separating substances according to phases (solid-liquid, liquid-liquid or liquid-gas). The term derives from the fact that coloured substances were originally separated as coloured bands that moved at differens speed down a column." Medicinsk ordbog dansk-engelsk engelsk-dansk.

The Danish term for chromatographic is kromatografisk. I have not seen any instances of bikromatografisk in Danish usage.

Hope this helps you on your way to finding a solution.