What is the ruling on the husband's money when he works for a company that prepares ready meals, some of which contain alcohol, knowing that he benefits from this money?

If a worker is directly involved in making foods to which alcohol is added, or assists in doing so, then his work is forbidden (haram (definition)). He must dispose of the money earned from it by spending it on the welfare of Muslims. It is not permissible for him to spend from it on himself unless he is poor, in which case he may take what is necessary for his essential needs. However, if he is not directly involved in making or assisting in making such foods, then his work is permissible (mubah (definition)) and his earnings are lawful (halal (definition)), although it is preferable for him to leave it if he finds another job.