Environment-friendly iron removal method of laterite nickel ore leaching solution without impurities brought in

The invention provides an environment-friendly iron removal method of a laterite nickel ore leaching solution without impurities brought in. The environment-friendly iron removal method is characterized by comprising the steps that (1) laterite nickel-magnesium ore is added to the laterite nickel ore leaching solution with the pH value less than 1.2 for neutralization until the pH value is 1.5-1.7, then magnesium carbonate or activated magnesium oxide is added for neutralization until the pH value is 1.9-2.1, and a neutralized leaching solution is obtained; (2) an oxidizing agent is added to the neutralized leaching solution until the concentration of ferrous ions in the leaching solution is less than 0.001 g/L, and an oxidizing leaching solution is obtained; (3) the oxidizing leaching solution is sent to a stirred state solution, the concentration of iron ions in a mixed solution is controlled to be 2-6 g/L, active magnesium oxide is added according to the amount of 1.5-3 times the mass of iron, the pH value