Is it permissible to lie about the reason for requesting a loan to fulfill essential needs instead of for trade?

You are not permitted to lie to the lender. Deceiving him into thinking you will borrow from him for trade, while your intention is to pay for essential needs, is considered deceit. This is because he might refrain from lending to you if he knew the truth of the matter. The situation worsens if you intend to make him understand that you will trade with his money for him, as a loan is a guaranteed debt, whereas a qirad (profit-sharing partnership) is a speculative investment that carries the possibility of profit and loss.