Reflexive pronoun refers to the subject of the sentence while the intensive pronoun emphasizes another noun or pronoun. That means that they do not refer to the subject. Intensive Pronouns- usually appears right near the subject of the sentence.
Reflexive: I made myself a sandwich. ( The reflexive pronoun is myself which refers to the subject I.)
Intensive: The president himself, appeared at the rally. (The pronoun himself emphasizes the subject president, and it appears near the subject.)