Am I allowed to put Sadaka from my loan money (which has interest)? Even if it is just 25 cents per week? If not would reading Quran be a type of Sadaka?

Your loan money is your own money if you are living in non Islamic country you take loan but it depends in which condition you have taken the loan
Ayatullah Sistani (may Allah protect him) says that: “: Taking an interest based loan is not permissible except for when it is very urgent; it is necessary that he should do so with the intention that it is a transaction without return, even if he knows that he will end up paying the capital as well as the interest. And he should not do so with the intention of getting the loan with the condition of paying interest.”
Yes Sadaqah can be given in the from of things also reciting Quran but if it is due upon you to give money as sadaqah then you have to pay cash.