Is there a sin in divorcing one's wife if she refuses to adhere to the Sharia-compliant conditions agreed upon before marriage, despite her subsequent attempts to mend what was broken?

If advice and admonition do not benefit the wife, then divorcing her is a kindness for which the husband will be rewarded, due to his zeal for the sacred limits of Allah.

If she requests to return, it is permissible to take her back if it is highly probable that she will become righteous, provided that firm covenants are taken and she repents to Allah. However, if it is highly probable that she will persist in misguidance, then her request should not be granted.