Treatment method of laterite-nickel ore high-pressure acid leaching liquid and high-pressure acid leaching treatment process of laterite-nickel ore

The invention provides a treatment method of laterite-nickel ore high-pressure acid leaching liquid and a high-pressure acid leaching treatment process of laterite-nickel ore. The treatment method comprises neutralization and optional reduction treatment conducted on leachate through ferronickel slag, wherein the ferronickel slag contains ferrous elements, and reduction treatment is conducted whenhexavalent chromium ions are contained in the leachate. Ferrous oxide and magnesium oxide in the ferronickel slag are used as neutralizers to be subjected to a neutralization reaction with free sulfuric acid in the leachate, and ferrous ions generated after the neutralization reaction of the ferrous oxide and the sulfuric acid are used as reducing agents to reduce hexavalent chromium in the leachate into trivalent chromium, so that one-step neutralization reduction is realized, and the process of neutralization and reduction reaction is shortened. The ferronickel slag is originally treated assolid waste, so that wast