Is it a condition for repentance to dispose of old usurious money that has been mixed with capital, or can it be kept as new capital after resolving not to return to usurious transactions?

Whoever has engaged in usury must repent to Allah by abstaining from it, regretting it, and resolving never to return to it, for Allah the Almighty says: "So whoever receives an admonition from his Lord and desists, he may have what has passed, and his affair is with Allah." If he was ignorant of the prohibition of usury and excused for his ignorance, he is not required to dispose of the usurious funds; his repentance is sufficient, and he may benefit from them. However, if the enquirer was negligent in asking about the ruling on usury—as his doubt about its prohibition indicates—then he has no excuse for his ignorance. He must dispose of the usurious interest by spending it on charitable causes. If he is unaware of the exact amount, he should act based on his best judgment and dispose of what he believes to be the predominant amount.