Dean137

I tired it yesterday befor eyour post with 100ml and the pH dropped to 4 after 2ml of HCl

Should have probally put that info in aswell The cleaning solution is NaOH and its diluted down with water to the required strength, and i made a typo and its a 300L tank

HI all, long time reader first time poster here I have a question and looking for some help. Its been along time since I used any chemistry I learned while doing my degree but for the life of me I cant figure out this. I have a 300L overflow tank with a PH of 13 it needs to be reduced to below 9 before it can be disposed of, I have 1M HCl available how much HCl do I need to add to achieve below PH9. Thank you for any help