How to decolorize sulfuric acid and phosphoric acid?
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I would like to ask how to remove color from high-concentration sulfuric acid or phosphoric acid
Try it with a color-removing activated carbon fixed-bed; I’m not sure how much sulfuric acid and phosphoric acid you have! For small-scale experiments, a fixed bed is not necessary, but the losses will be higher; the resistance issue must be taken into account when designing a fixed bed!
Agreed; activated carbon is generally used for decolorization.
The color of industrial sulfuric acid is generally that of iron ions, and this color is difficult to remove; therefore, extra effort is put into corrosion protection, especially in pipelines, during the production process. The color of phosphoric acid is mainly associated with wet-process phosphoric acid, as well as the colors of certain ions. The solution to this issue is to select phosphate ores carefully; moreover, phosphoric acid used in fertilizers does not require high color standards – it is sufficient to remove elements such as arsenic.
Decolorization can also be achieved using adsorption resins, but this requires high standards for such resins. The regeneration of the resin after decolorization is also easy; it can be done by heating with steam.
It also depends on how the color of your acid is formed; that’s very important