Method for separating ferrum and aluminum from potassium-bearing rock intermediate solution

The invention discloses a method for separating ferrum and aluminum from a potassium-bearing rock intermediate solution, and belongs to the technical field of chemical industry. The method includes the steps that a certain quantity of oxidizing agent and a certain amount of ammonium hydroxide are added into the potassium-bearing rock intermediate solution, solid-liquid separation is carried out after reacting is carried out for a period of time, separated-out solid is dried, and ferrum ammonium vanadium is obtained; and a purifying agent is added into separated-out liquid for purifying treatment, then solid-liquid separation is carried out, and obtained liquid is a ferrum-free aluminum solution. According to the method, the solution containing the aluminum and the ferrum is purified through a two-step ferrum removing method, most of the ferrum is removed through a ferrum ammonium vanadium method firstly, and then ferric ions in the solution are further removed through organic matter; and due to the two-step reaction, the concentration of the dissolved ferric ions is reduced to be lower than 10, and the losses of the aluminum are controlled to be lower than 8%.