Same CAS number, different reject rate: why recycled LiOH needs supplementary Na and Ca limits

The news

Your lithium hydroxide supplier’s feedstock story is about to get more complicated. N.A.N. GreenMet and Silox have formed a joint venture targeting large-scale lithium-ion battery recycling, aiming to build circular recovery infrastructure for critical minerals including lithium, cobalt, nickel, and manganese (Chemical Industry Digest, 2026). Separately, Chemical Engineering Magazine has published a cost analysis of electrolysis as an alternative production route for lithium hydroxide, raising questions about whether the LiOH on your next CoA was made by carbonation-causticization, direct electrolysis, or hydrometallurgical recovery from spent cells (Chemical Engineering, 2026). The production method matters because it determines the impurity fingerprint of what arrives in your drum.

Why the production route shows up on your reject log

Lithium hydroxide monohydrate (LiOH·H₂O, CAS 1310-66-3, 41.96 g/mol) and anhydrous lithium hydroxide (LiOH, CAS 1310-65-2, 23.95 g/mol) each carry a single CAS number whether the lithium came from spodumene concentrate, brine evaporation, electrolysis, or a recycled cathode leach. The CAS number tells you nothing about what rode in with it.

Hydrometallurgical recovery of LiOH from end-of-life lithium-ion cells processes a mixed-metal feedstock: cathodes containing cobalt sulfate, nickel sulfate, and manganese sulfate, along with residual aluminum and copper from current collectors. Separation steps target battery-grade purity, but the impurity slate differs from virgin routes. Sodium and calcium levels, in particular, can run higher in recycled streams when wash stages are not optimized.

There is no industry-standard battery-grade or recycled-grade designation for lithium hydroxide, so the specification that governs a lot is the supplier’s CoA scope: the assay and the handful of impurities the supplier chooses to report. If your purchase order does not carry its own limits on sodium, calcium, copper and aluminum, the gap is between what the CoA measures and what your cathode precursor mixer will tolerate. A lot can match every line the supplier reports and still fail on an impurity nobody measured.

The electrolysis route introduces its own variable: electrode degradation products. Chemical Engineering’s cost analysis flags production economics, but for procurement the question is whether the supplier’s process-control maturity matches the purity your formulator needs. Ask for the production method on the CoA. If the supplier will not disclose it, that is data you are missing.

Here is the honest trade-off: recycled-origin LiOH may eventually carry a price discount or a carbon-intensity advantage, but today the verification burden sits with the buyer. With no recycled-grade label to buy against, you are qualifying a process, not a label.

What changes for buyers of these four battery salts

The sourcing decision that changes is qualification scope. If you buy LiOH, cobalt sulfate, nickel sulfate, or manganese sulfate today from a single virgin-route supplier, the GreenMet-Silox JV and similar recycling ventures mean a second-source option will emerge with a fundamentally different impurity profile. Your qualification protocol needs to test for that difference explicitly, not assume grade equivalence because the CAS matches.

Contract language changes too. EU Battery Regulation (EU) 2023/1542 will require recycled-content disclosure for batteries placed on the European market, with phased lithium, cobalt, and nickel content thresholds. If your material ends up in a cell sold into the EU, your supplier’s inability to document feedstock origin becomes your compliance problem. Add a recycled-content declaration clause now, even if your current supplier ships 100% virgin material. The clause costs nothing; retrofitting traceability later costs months.

Is your spec ready before the first recycled lot arrives?

The GreenMet-Silox JV is infrastructure, not product. Watch for their first published product spec sheet and sample-lot availability announcement. That is the signal that recycled LiOH is moving from pilot to commercial qualification.

On the regulatory side, the EU Battery Regulation’s delegated acts specifying exact recycled-content calculation methodology are still being finalized. The methodology determines whether a buyer can count recycled LiOH purchased from a third-party recycler or only material recovered in a closed-loop arrangement. That distinction will set the market structure for verified recycled supply.

The decision you face is not whether to source recycled battery minerals. The decision is whether to write the spec before or after the first lot shows up on your dock with an impurity your lab has never tested for. One of those options gives you negotiating power. The other gives you a hold tag.

What to do in the next two weeks

1. Pull three consecutive lot CoAs from your current LiOH supplier. Check whether sodium, calcium, copper, and aluminum are reported. If they are not, request supplementary analysis. You cannot set a tolerance band on an impurity you have never measured.

2. Add production-method disclosure to your supplier questionnaire. One line: “State the primary production route (brine, spodumene conversion, electrolysis, or hydrometallurgical recovery from recycled cells).” A supplier who refuses to answer is a supplier whose process may change without notice.

3. Verify TSCA status for any novel co-products. Lithium hydroxide itself is on the EPA TSCA Inventory. But recycling processes can generate intermediate or co-product streams that are not. EPA’s August 2026 notice (91 FR 55332) confirms active PMN and NOC processing under TSCA Section 5. A PMN filing carries a 90-day statutory review period. If your recycled-source supplier is importing a substance not yet on the Inventory, the lot does not clear until that review closes.

4. Flag GHG reporting exposure. EPA’s 2024 amendments to the Greenhouse Gas Reporting Rule (40 CFR Part 98) expanded reporting requirements to additional energy-intensive source categories including coke calcining and ceramics manufacturing (89 FR 31802, April 2024). Battery-materials processing sits in this energy-intensive zone. If your total-cost-of-ownership model does not include the supplier’s carbon-reporting compliance cost, it understates the landed price of virgin material and overstates the premium of recycled.

Related on RawSource

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• Ultra-High Purity Colloidal Silica: Semiconductor Sourcing: details how buyers set supplementary impurity limits for advanced materials, a useful model for writing recycled-grade LiOH specs.
• Activated Alumina Sourcing: Specs for Water and Gas Use: illustrates how production-route differences affect impurity profiles and qualification protocols for industrial mineral purchases.
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