Lanthanum (La) is one of the rare earths where recycling can be more than a talking point, because a big chunk of demand sits in two industrial loops that generate identifiable secondary feed: spent FCC catalysts and spent NiMH batteries. Everything else is smaller, dirtier, or too diluted to be a dependable lanthanum source.
Most "lanthanum recycling" starts as waste processing, not metal recycling.
FCC catalysts used in petroleum refining commonly contain rare earths (especially La and Ce) as stabilizers in zeolite-based formulations. When catalysts are spent, lanthanum is still physically there, often at percent-level in the solid. Recovery has been studied for decades and is now a mature technical topic.
Most lanthanum recovery flowsheets from spent FCC catalysts follow a recognizable pattern:
A widely cited practical route is acid leaching followed by oxalate precipitation; one study specifically reports strong lanthanum leaching performance with nitric acid and then recovery via oxalate precipitation.
More recent work focuses on turning leach solutions into value-added lanthanum-containing products and compares process options for recovering lanthanum from FCC-catalyst leachates.
If you see "lanthanum from catalysts" pitched as easy money, it usually ignores wastewater handling and the cost of converting a leachate into a spec product.
NiMH anodes commonly use rare-earth metal hydride alloys where lanthanum is a major component (mischmetal-style). This makes NiMH one of the more lanthanum-dense "urban mining" streams.
NiMH recycling typically starts with physical handling, then turns into hydrometallurgy:
A 2022 paper reports recovery of REEs from spent NiMH using a leaching approach followed by selective precipitation, with high precipitation efficiencies for La under optimized conditions.
A 2023 review covers the broader toolbox for NiMH REE recovery and makes the same point implicitly: the chemistry is workable, but the economics are about integrated processing and separation, not a single clever step.
Lamp phosphor powders can contain several rare earths (including La), but industrial recovery is complex and many recycling systems historically focused on safe handling and mercury management rather than rare earth separation.
If you include this stream in a lanthanum recycling narrative, keep it honest:
Most real-world outputs are one of these:
In other words, recycling often substitutes for upstream mining only if the recycler can also handle part of the midstream separation and finishing burden.
Recycling can matter for lanthanum because its biggest industrial uses generate recoverable waste streams (catalysts and NiMH). But it is not a magic supply unlock:
A foundational review of rare earth recycling highlights catalysts, NiMH batteries, and lamp phosphors as key application streams in REE recycling discussions, which lines up with the lanthanum reality.
Spent FCC catalysts and NiMH batteries. They are the most lanthanum-linked streams with workable chemistry and realistic collection pathways.
Not usually. Many processes recover REEs as mixed precipitates first (oxalates, phosphates). Producing high-purity La₂O₃ requires extra purification and sometimes full separation steps.
Because the material is mixed, contaminated, and processing is complex and costly. Many lamp recycling systems historically prioritized safe handling and other recovery goals, and REE recovery has been harder to scale economically.
Not entirely. Recycling can reduce dependence on primary mining and provide supply diversification, but it's constrained by collection infrastructure, processing economics, and the need for separation capacity. It's best viewed as a complementary supply source rather than a complete replacement.