Compare precious metal catalyst quotations by reconstructing the metal quantity first, then separating the metal charge from catalyst manufacturing and other charges. For a water-wet supported catalyst, dry-basis metal loading must be applied to the supported dry catalyst quantity, not directly to delivered wet weight. Confirm whether the quotation includes purchased metal, requires a transfer from a metal account or uses leased metal. A low price per wet kilogram can otherwise reflect more water or an excluded metal obligation. This comparison supports commercial screening; equivalent metal quantities do not establish equivalent catalytic performance.

Establish What the Metal Percentage Describes

“5% palladium on carbon” is insufficient for commercial reconciliation unless the supplier defines the denominator.

Confirm whether the percentage means elemental palladium as a fraction of:

• The finished dry catalyst, including metal and support.
• The supplied wet catalyst.
• The support mass before metal addition.
• Another explicitly defined analytical basis.

Those expressions are not interchangeable.

Commercial products do use dry-basis loading for wet material. Sigma-Aldrich’s palladium-on-carbon product 520829, for example, identifies a 10 wt.% loading on a dry basis and a wet carbon support. That product description illustrates the reporting convention; it does not establish the specification of another grade. sigmaaldrich.com

Also distinguish elemental metal content from compound assay. A palladium complex’s purity percentage is not its elemental palladium mass fraction. The calculation below concerns water-wet supported powder catalysts, using Pd/C as the example. Soluble complexes, unsupported powders and other supply forms require their own quantity basis.

Convert Wet Quantity to Dry Catalyst and Contained Metal

Where the agreed metal loading applies to the finished dry catalyst:

Dry catalyst quantity, kg = supplied net wet weight, kg × dry-matter fraction

Contained metal, kg = dry catalyst quantity, kg × dry-basis metal fraction

If the applicable loss-on-drying result establishes the dry-matter fraction:

Dry-matter fraction = 1 − loss-on-drying fraction

Enter 50% as 0.50 and 5% as 0.05.

Evonik’s sampling and weighing guidance gives a corresponding correction between wet catalyst quantity and desired dry catalyst quantity. It also explains that repeated opening can change moisture content and make the original labelled value unrepresentative.

For purchasing, confirm that the net weight, drying correction and metal result represent the same lot and material condition. A generic maximum water specification supports a different calculation from an actual batch result.

Use the supplier’s defined analytical basis. “Dry basis” describes the calculation; the delivered material should remain in its specified supply form.

Avoid Applying the Correction Twice

If the certificate already reports elemental metal per kilogram of supplied wet catalyst, multiply that result directly by net wet weight.

Do not apply another dry-matter correction.

Likewise, confirm that a stated dry quantity includes the supported metal. A loading expressed relative to support mass requires a different calculation from loading expressed relative to the finished dry catalyst.

An unexplained loading basis is a reason to hold the comparison, rather than select the interpretation that produces the lowest apparent cost.

Separate Metal Provision From Catalyst Manufacturing

A catalyst quotation can combine several different obligations.

Evonik’s published metal-management services distinguish purchase, lease and transfer arrangements and describe metal weight accounts and different purchasing mechanisms. These are examples of commercial structures that require separate comparison; they are not automatically included in every catalyst offer.

For an outright purchase, obtain the metal-price reference and the event that fixes it. Record any premium, currency conversion and quotation validity.

For customer-supplied metal, identify the quantity debited from the account. Do not compare a manufacturing-only invoice directly with an offer that includes buying the metal.

For leased metal, keep the lease obligations visible instead of treating the absence of an upfront metal purchase as a reduction in metal consumption.

Compare the Same Catalyst Duty

The following hypothetical example isolates the effect of water content and fee basis.

Assume both candidates have already been accepted for the intended duty, including their different water contributions. Each offer supplies 50 kg of dry catalyst containing 5.0 wt.% palladium. Metal is purchased outright at the same illustrative price.

All figures are invented. They are not current palladium prices, supplier quotations or evidence of grade equivalence.

Offer B appears substantially cheaper per wet kilogram. For the same dry catalyst and contained palladium quantities, its stated total is US$250 higher before other charges.

The calculation exposes the denominator difference. It does not demonstrate that two real catalysts can deliver the same reaction result.

If both quotations use the same metal quantity and metal-price basis, the remaining difference can be traced to manufacturing and other charges. If their metal-price bases differ, reconcile that difference before attributing the price gap to catalyst manufacture.

Keep Metal Inventory Separate From Reaction Performance

Metal loading measures quantity. It does not independently describe how that metal is presented to the reaction.

Heraeus describes supported catalyst manufacturing through different support materials, geometries, impregnation procedures, reduction and passivation operations. These distinctions explain why a metal percentage alone is an incomplete description of the catalyst supplied.

For a proposed replacement, keep the exact grade and supply form attached to the commercial calculation. Where application qualification remains necessary, compare candidates under the intended reaction conditions with a clearly stated dry-catalyst or metal-charge basis.

The acceptance decision should address the outcomes relevant to that process, such as conversion, selectivity, filtration or residual metal. A lower purchase cost per gram of contained metal cannot substitute for that evidence.

This also limits a simple “higher loading means lower consumption” argument. Changing the metal fraction changes the relationship between metal and support quantities; the required catalyst charge must be established for the candidate grade.

Treat Recovery Credits as a Separate Calculation

Fresh-catalyst metal quantity and recoverable metal are different accounting stages.

Evonik’s recovery guidance identifies possible losses through handling, metal leaching and fine-particle losses during filtration. It describes recovered metal being credited to a metal weight account after recovery. The fresh catalyst’s theoretical metal inventory therefore should not be treated as a guaranteed future credit.

If a quotation includes an expected recovery credit, identify:

• The material and sampling basis used to determine returned metal.
• The payable or credited metal quantity.
• Refining and other deductions.
• The valuation basis and timing of the credit.
• Whether settlement is in cash or metal-account weight.

Keep an estimated credit visibly separate from the initial purchase calculation. A closed-cycle cost assessment can include recovery, but it needs evidence for the actual process and settlement arrangement. Do not insert a universal recovery percentage.

Decide Whether the Offers Are Ready to Rank

The grade specification establishes the loading and supply form. The batch certificate connects analytical results to the lot. The quantity record establishes net delivery weight. The commercial quotation defines the metal and manufacturing obligations.

ChemicalCell’s Precious Metal Catalysts directory provides a starting point for browsing the broader category. Confirm the specific supported catalyst grade, wetting medium and technical documents before treating a listing as a candidate for this calculation.

Reconcile the Metal Obligation Before Selecting the Lower Price

A useful comparison shows three quantities explicitly: kilograms of supplied wet catalyst, kilograms of finished dry catalyst and grams of contained precious metal. It then identifies whether that metal is purchased, supplied from an account or leased.

Obtain one reconciled quotation sheet for each candidate stating those quantities, the loading and drying bases, the metal-price reference and fixing rule, the manufacturing-charge unit, included delivery costs and any separately estimated recovery credit. Rank technically qualified offers only after those fields describe comparable obligations.