Uses
C.I. Acid brown 121 is an acidic brown dye that can be adsorbed and removed by bentone clay.
Preparation
4-Amino-5-hydroxynaphthalene-2,7-disulfonic acid?diazo, Coupled with resorcinol, 4-Nitrobenzenamine diazo, and the generation of single accidentally coupled nitrogen compounds, its product again with diazo of 2-Amino-4-nitrophenol coupling.
Properties and Applications
dark yellow light brown. Soluble in water for brown. The strong sulfuric acid for wine, dilute after brown precipitation. In water solution to join strong hydrochloric acid with brown precipitation; Join rare sodium hydroxide solution for red brown.
References
[1] Baskaralingam P, Pulikesi M, Elango D, et al. Adsorption of acid dye onto organobentonite[J]. Journal of hazardous materials, 2006, 128(2-3): 138-144.