Provided are purification methods, comprising: (a) providing an organic solvent and a phenolic peroxide formation inhibitor, wherein the organic solvent has a first boiling point at standard atmospheric pressure (bp1) and the phenolic peroxide formation inhibitor has a second boiling point at standard atmospheric pressure (bp2) that satisfy the following inequality (I): bp2≤(1.10)(bp1)  (I); and (b) heating the organic solvent and the phenolic peroxide formation inhibitor to a temperature causing the organic solvent and phenolic peroxide formation inhibitor to vaporize, and (ii) condensing the vaporized organic solvent and peroxide formation inhibitor to provide a purified mixture of the organic solvent and peroxide formation inhibitor. The methods find particular use in the purification of solvents that are useful in process chemicals for the manufacture of semiconductor devices.