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Swapping Sulfuric acid from the B&W reversal process

Eddy Lin

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Hello everyone
I am buying chemicals for the B&W reversal process.
I don't want to use Sulfuric acid for the bleach formula.
I use Sodium bisulfate.
But I have seen many differerent concentration.

1. 25g/1L
2. 50g/1L
3. 55g/1L
4. 60g/1L
5. 65g/1L

Which is much accurate?
 

revdoc

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Which bleach are you using? Dichromate or permanganate?

I'm not sure that the amounts matter greatly in this case. I make 250ml of reversal bleach with 1g of potassium dichromate and about 5g of sodium bisulfate. I don't measure the bisulfate exactly... about 1 teaspoon is close enough. The result bleaches film in less than a minute.
 
OP
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Eddy Lin

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I use permanganate.
 

Raghu Kuvempunagar

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Here is the substitution:

"For every gram of concentrated sulfuric acid or equivalent substitute 2.40 grams of anhydrous sodium bisulfate. If the recipe calls for concentrated sulfuric acid then 1 ml of acid weighs 1.84 grams. Therefore for 1 ml of concentrated acid substitute 4.42 grams of anhydrous sodium bisulfate."
 
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