Mixed solvents, alpha effect

Solvents which are depleted of stabilizers (amine or alpha epoxide) may become acidic. The following method determines the combined effect of both alkaline (amine) and neutral (usually epoxy) stabilizers. The determination is done in two steps. First solvent is mixed with hydrochlorination reagent (0.1N HCl), then the excess is titrated with 0.1N sodium hydroxide in the presence of 0.1% bromophenyl blue as an indicator. 

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