Why is sulphuric acid not used during the reaction of alcohols with KI?

Explanation

`H_(2)SO_(4)` is an oxidising agent. It oxidises HI produced during the reaction to `I_(2)` and
`2KI+H_(2)SO_(4)to 2KHSO_(4)+2HI,2HI+H_(2)SO_(4)toH_(2)O+I_(2)+SO_(4)`
thus prevents the reaction between an alcohol and HI to form an alkyl iodide. to overcome this difficulty, a non-oxidising acid such as `H_(3)PO_(4)` is used instead of `H_(2)SO_(4)`.
`underset("Ethanol")(CH_(3)CH_(2)-OH)+KI+H_(3)PO_(4) overset(Delta)to underset("Iodoethane")(CH_(3)CH_(2)-I)+KH_(2)PO_(4)+H_(2)O`