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Anodizing Process Control
Control & Recovery with Pure Cycle's Diffusion Dialysis

Sulfuric Acid Anodizing.

Applied Diffusion Dialysis.

     The Anodizing process produces an oxide film on an Aluminum part that is made the anode in an electrolytic cell.  Sulfuric acid is used in Type II & Type III Anodizing.
     By controlling the electrolyte and the anodizing conditions, such as temperature, current density and air agitation, one can produce Aluminum coatings with almost any desired property.
     As Aluminum and other alloying metals build up in the bath, process parameters must be continually adjusted to maintain hardness, thickness and color consistency, and more energy is required to produce the anodic coating. Anodizing consistency is greatly improved by maintaining contaminants at a steady-state.


Why should I use Diffusion Dialysis with Sulfuric Acid Anodizing process?

   Diffusion Dialysis is excellent for the recycling of sulfuric acid anodize solutions.  Diffusion Dialysis provides improved anodize quality, reduced burning, reduced additive consumption, consistent anodized color and consistent anodic thicknesses, with cooler and less energy demanding baths, while eliminating production down-time associated with the dumping and remaking of the anodize bath.
      The passive, continuous Diffusion Dialysis process enables the anodizer to efficiently remove and control the dissolved aluminum content in the bath while recovering and returning a high percentage of the sulfuric acid back into the process bath.  The Diffusion Dialysis process also removes and controls other contaminant build-up in the anodize bath, such as: copper, iron, lead, magnesium, manganese, phosphate, silicon and zinc, while producing a minimum of rejected waste by-product for subsequent treatment and disposal.



Acid Dump Volume (Gallons)

Freq of Acid Dump

50 100 200 500 1000
Once / Day A-60 A-120 A-250 A-500 A-1000
Once / Week A-15 A-15 A-30 A-120 A-250
Once / Month A-5 A-5 A-15 A-30 A-60

  Acid Recycling System Model Number*
*Based on 24 Hours per Day / Seven Days per Week of Operation.
Actual Calculation: Bath Volume Divided by Calendar Days of Bath Life Equals Gallons per day Required.

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