Is a divorce effected if a man says to his wife in a state of anger, "You are unlawful to me for a month, I will not touch you," and then, "You are unlawful to me for two months, I will not touch you," intending sexual intercourse, knowing that he had previously uttered the same phrase with the intention of divorce, but this time he did not intend divorce and the words came out without intention?

If you told your angry wife, "You are unlawful to me for a month, I will not touch you again," then you made the period two months without intending divorce, and she understood that your intention was to abstain from intercourse with her:

If anger made you lose your consciousness, then this is a laghw (idle talk) and not binding. However, if anger did not reach this extent, then since your intention was to make intercourse with her unlawful, this is a temporary zhihar. The preponderant opinion is that acting upon the temporary nature is valid. You have the choice between abstaining from intercourse with her for the specified period without expiation (kaffarah (definition)), or performing the expiation for zhihar first then having intercourse with her. It is not permissible to have intercourse with her before performing the expiation.

As for your previous statement: "You are unlawful to me for a month," if you intended divorce by it and your anger did not make you lose your sanity, then a revocable divorce occurs – if you had intercourse with her within the month – and the temporary nature is not accepted, and one divorce counts against you. If it was the first or second divorce, you may take her back during her iddah (definition) (waiting period). If the iddah ends, she does not become lawful for you except with a new marriage contract. However, if it was the third divorce, she is unlawful to you until she marries another husband.

And Allah knows best.