Is swearing "By Ali, by triple divorce, you shall be حرمانه علي, I will not talk to you online until I go on leave" considered an oath or a divorce, and what is its expiation?

The wording mentioned is open to more than one interpretation, depending on your intention behind it. It could signify an oath by triple divorce and حرمة (prohibition) combined, or the suspension of حرمة upon her speaking before the leave. The term حرمة itself might imply divorce, or ẓihār (a form of divorce by injurious assimilation), or an oath, or it might mean nothing at all. Therefore, it is preferable to present your question to trustworthy scholars in your country, or to clarify the wording and the intention behind the حرمة.