Is it permissible to benefit from the interest accrued on a sum of a bank loan that was deposited into an account after the need for it ceased, in exchange for the interest that the bank takes on the same loan?

It is not permissible to benefit from usurious interest, and one must dispose of it by spending it on charitable causes. Furthermore, money must be withdrawn from an interest-based bank unless there is extreme necessity and no Islamic bank is available.