In Brazilian refining, petrochemicals, fine chemistry or fertiliser plants, every lot of spent catalyst going to disposal is treated as a maintenance event: heavy weight, scrap auction, single buyer takes everything. The price agreed in that model is usually the price of the inert fraction. The fraction with real value gets included silently — without the generator knowing how much it cost.
Practical result: a Brazilian industrial plant frequently sells as scrap material that, with technical screening before sale, would yield multiples of what it yielded. This text explains why this happens, what changes when there is screening, and what NOT to do.
Why industrial catalyst is not homogeneous
New commercial catalyst is a very well characterised material: declared grade, datasheet, certificate of origin. Spent catalyst is not. Through the operating cycle it can accumulate:
- Coke — carbon deposit covering active sites, lowering surface reads.
- Contamination — heavy metals, sulphur, lead, sodium from the feed, changing matrix and recoverability.
- Mechanical mixing — when the reactor is unloaded, top, middle and bottom fractions usually go into the same big bag with different profiles.
- Spent vs. active fraction — in long-campaign catalyst, the bed wears unevenly.
- Inter-lot mixing — during turnaround, multiple lots end up in the same warehouse awaiting disposal. Premature mixing kills future screening.
Why selling the full lot without screening is expensive
If the rich fraction is sold at the price of the poor fraction, all additional value goes to the specialised buyer downstream. Economically that is normal — the buyer assumed risk, ran their own screening, added value. What is often not evaluated is that pre-sale technical screening is cheaper than it looks, and the upside lands on the right side.
Simplified comparison:
- No screening: 5,000 kg of mixed lot sold as catalytic scrap at average price. You don't know what you sold.
- With screening: same lot separated into rich fraction (say, 800 kg with relevant Pt), intermediate fraction (1,200 kg with Ni/Mo) and inert fraction (3,000 kg with low recoverability). Each goes to the right channel at the right price.
The exact figure depends on the lot and market. The point is that in option one, the upside is unknown.
How technical screening of an industrial lot works
- Lot history. Which unit generated it. Which commercial catalyst it was. Which campaign. Why it was discarded.
- Visual inspection. Physical form (pellet, sphere, monolith, metallic support), coke level, fines, pellet integrity.
- Representative sampling. Sub-samples at multiple points, mixed, quartered, final aliquot. Documented with photos and weight.
- Preliminary XRF. Immediate read of the prepared sample. Directs whether confirmatory assay is worth running, and which technique.
- Confirmatory assay when justified. ICP-MS, ICP-OES or fire assay at qualified partner laboratory, with documented chain of custody.
- Commercial plan. Direct purchase of rich fraction, intermediation toward specialised recoverer, or guidance on disposal of inert fraction.
What NOT to do
- Do not mix lots from different units in the same big bag before screening. Premature mixing cannot be undone.
- Do not wet the material. For dust control, use minimal controlled humidification — soaking changes chemistry and prevents proper analysis.
- Do not auction by gross weight before at least visual screening. You are auctioning information you don't have.
- Do not rely on surface XRF without sampling. For lots with coke or surface contamination, no-prep reads systematically underestimate.
For the generator: what to ask before signing
If a purchase offer arrives now, ask before closing:
- Preliminary lot analysis — XRF on arrival or sampling with assay.
- Pricing broken down by fraction when applicable, not single price.
- Documented chain of custody (weight, photos, identification).
- Applicable tax documentation case by case, including NF-e where due.
Even if final sale goes to the same buyer who made the original offer, having this information changes negotiation position.
Technical page on industrial catalyst →
To discuss a specific lot with the team, send process datasheet and photos via the submission form or directly on WhatsApp. Preliminary screening usually goes out the same business day.