Opportunities for variable feed in REE and P extraction - OPTIREEP

OPTIREEP is a research project that addresses one of Europe’s key resource challenges by developing robust and flexible processes for the extraction of rare earth elements and phosphorus from raw materials with varying composition and mineralogy. Through extensive characterization, thermodynamic modelling and laboratory studies aligned with a proposed process, new knowledge is gathered that will support future implementation.

Background

Rare earth elements are essential for high-performance permanent magnets in wind turbines, electric vehicles, robotics, and defense applications, while phosphorus is a crucial nutrient for agriculture. The EU is almost entirely dependent on imports for both, making them critical raw materials (under the European Critical Raw Materials Act.

LKAB has developed a hydrometallurgical process (REEMAP) to produce phosphoric acid and oxides of rare earth elements, with gypsum of commercial value as a by-product, from apatite concentrate produced from mine tailings generated during enrichment of magnetite ore. Based on a pre-study, MULTIREEP (https://www.vinnova.se/p/multimineralanvandning-for-rena-ree-och-fosforprodukter-multireep/), the process originally tailored for apatite tailings from the Malmberget mine may after adaptation have the potential to handle apatite concentrate feeds from different mines with various apatite grade, as well as feeds containing other REE- and P-bearing minerals, like monazite, allanite, etc.

Purpose and goals

OPTIREEP aims to support future self-sufficiency in rare earth elements and phosphorus in Sweden and Europe by generating knowledge and process foundations for extraction from raw materials with varying quality and mineralogy. The project will identify how raw-material characteristics and process conditions jointly influence element distribution, extraction, recovery, separation, and purity, develop innovative process steps, and provide a basis for industrial implementation.

Implementation

OPTIREEP advances the MULTIREEP developments for integrated recovery of phosphorus and rare earth elements from variable mineral sources. The work is carried out through production and characterization of apatite concentrates, systematic laboratory studies including mineral-specific pre-treatment, optimized leaching with examination of element distribution, innovative separation/purification of products, reagent regeneration, and environmental analysis. Thermodynamic modelling supports planning and evaluation of results. A PhD student (PhD project 2026-2029) will focus on the speciation of elements in selected hydrometallurgical steps of the process assessing the interaction between mineral properties and chemical system. Different feed materials are used in the experiments, which are performed both in batch mode and in configurations aligned with a potential process flow sheet.

Project Partners

• Luleå University of Technology – Process metallurgy act as project leader and conduct hydrometallurgical studies, Ore geology focuses on characterization, and Chemistry of Interfaces supports characterization using NMR
• LKAB Minerals AB-Industrial partner, has a process for the production of phosphoric acid and rare earth elements
• Luossavaara-Kiirunavaara AB – Industrial partner, produces ferrous products for steelmaking and has tailings that are enriched to an apatite concentrate, the feed material for rare earth elements and phosphorus extraction