Loss on Ignition (LOI) vs Loss on Drying (LOD): The Spec Ambiguity That Causes Most Claims

Loss on Ignition (LOI) is the mass loss of an alumina, zeolite, or hydroxide powder after firing at 1000-1100 degC for 1-2 hours (ISO 3262-1, ASTM C25). Loss on Drying (LOD) is the mass loss after oven drying at 105-110 degC for 2 hours (ISO 787-2, ASTM D280). Both numbers appear on almost every Certificate of Analysis (CoA) for activated alumina, molecular sieve, pseudo-boehmite, aluminum hydroxide (ATH), and tabular alumina. Yet they answer fundamentally different questions, are determined by completely different test conditions, and are routinely confused in specification clauses — leading to claims, rejected shipments, and 30-90-day disputes that cost buyers and suppliers far more than the material itself.

This post targets procurement engineers who write or review specification clauses for industrial adsorbents and alumina powders. We cover the 4 reasons the two numbers cannot be substituted, the 6 measurement protocols (with the temperature/time/sample-mass table), the 5 material-specific reference ranges, the typical-claim mechanism that drives a USD 15,000 freight rejection, and a specification clause you can copy into your next RFQ. The molecular sieve example (where a 22 percent LOI is normal but a 22 percent LOD is a reject) is worth the read on its own.

For buyer-side QC auditors, the same data applies to incoming inspection: if you only check one number on the CoA against your spec, you are missing the other half of the moisture + decomposition story. For supplier-side quality managers, the dispute-resolution flow at the end of this post is the same workflow you should propose in writing when you sign a new PO.

Why LOI and LOD Are Not Interchangeable

The 4 reasons the two numbers cannot be substituted, with the typical magnitude of the disagreement:

Reason 1: Different Temperatures, Different Chemistry

LOI fires at 1000-1100 degC. At that temperature, every chemically combined volatile is driven off: structural water (zeolite framework -OH, pseudo-boehmite gel water), hydroxide decomposition (ATH and boehmite decompose to oxide + water between 200-600 degC), residual carbonates (if any), residual organics (surfactants, lubricants), and physically adsorbed moisture. LOD dries at 105-110 degC, which removes only free moisture (surface water, pore water, capillary water). The chemically combined water in a hydrated alumina or a zeolite framework is NOT removed by LOD.

Typical magnitude: activated alumina at 6-8 percent LOI shows 0.5-2 percent LOD. Molecular sieve 4A at 22 percent LOI shows less than 1.5 percent LOD. ATH at 34.6 percent LOI shows less than 0.5 percent LOD. Pseudo-boehmite at 25-30 percent LOI shows 5-15 percent LOD (gel stage retains free water in the macroporous gel network). A buyer specifying LOD on pseudo-boehmite tests free moisture, not aluminum-hydroxide content.

Reason 2: Different Times, Different Completion

LOI holds the sample at peak temperature for 1-2 hours (ISO 3262-1 specifies 2 hours; some methods use 1 hour). LOD holds for 2 hours (ISO 787-2). The LOI endpoint is complete decomposition — for ATH, this is the full conversion of Al(OH)3 to Al2O3 + 3 H2O. The LOD endpoint is mass equilibrium at 105 degC, which means the sample is "dry" by mass-loss definition but still contains all its chemically combined water and a small amount of adsorbed water (about 0.1-0.3 percent at 105 degC relative to a sample dried to constant weight at 300 degC).

Implication: a 1-hour LOI may understate LOI by 0.3-1.0 percent for slow hydroxyl release (high-density pseudo-boehmite). A 2-hour LOI is the conservative reference.

Reason 3: Different Sample Mass, Different Crucible Geometry

LOI uses 1-5 g of sample in a platinum or porcelain crucible, ignited in a muffle furnace. LOD uses 1-10 g in a glass weighing bottle or aluminum dish, dried in a convection or vacuum oven. The sample-mass matters because (a) thick beds trap moisture and skew LOD low, (b) thick beds trap decomposition gases and skew LOI high (carbonates and organics only partially release). The standard practice is a thin bed (less than 5 mm) for both methods.

Implication: a 10 g sample in a deep dish may report LOD 0.5 percent when a thin-bed LOD would show 0.8 percent. The two are not directly comparable.

Reason 4: Different Atmospheres, Different Completeness

LOI is typically performed in air (oxidation atmosphere), which drives off carbon as CO2 and organics as CO2 + H2O. Some specialty methods use nitrogen or oxygen atmosphere for specific decomposition profiles (e.g., black-mass recovery, catalyst regeneration studies). LOD is always in air. The atmosphere matters for materials with carbon residues: a 0.5 percent carbon residue on a regenerated catalyst will appear as 0.5 percent in air-LOI but may appear as 0.1 percent in nitrogen-LOI (because carbon does not fully combust to CO2 without oxygen).

The 6 Reference Protocols Buyers and Suppliers Should Cite

Six standards govern LOI and LOD on alumina, zeolite, hydroxide, and tabular powders. The 4 most cited are listed first; the 2 specialty standards are listed at the end of this section. A specification clause that cites the standard by number, plus the temperature, time, and atmosphere, removes 90 percent of the dispute surface.

Note on ASTM D1209: this is the plastics-industry LOI (also called Ash Content when the residue is weighed). It uses lower temperature (750-850 degC) than the ceramic-industry LOI (1000-1100 degC). A supplier that cites ASTM D1209 for a polymer-filled ATH will report a lower LOI than a supplier citing ISO 3262-1, because the lower temperature does not fully decompose the Al(OH)3. The 1.0-2.0 percent gap on a 65 percent-ATH polypropylene compound is a real source of dispute when buyers and suppliers cite different standards.

Note on ISO 15901-3: this is not strictly an LOI method, but the outgas step at 300 degC for 16 hours (used to clean the sample before nitrogen sorption) is functionally a high-temperature LOD. Some labs report the outgas mass loss as "LOD at 300 degC" - this is a separate value from the standard 105 degC LOD and should not be conflated.

5 Material-Specific Reference Ranges

The 5 product categories most likely to appear on a B2B adsorbent/alumina RFQ, with the typical LOI and LOD ranges a buyer should expect. These ranges are compiled from published supplier datasheets (Almatis, BASF, UOP, Zeolyst, Honeywell UOP, Tosoh, JGC C&C), industry reference books (Cejka, Corma, Zones - Introduction to Zeolite Science and Practice), and our 14-year inbound-QC database at AluminaWorld. They are typical industry ranges, not a single supplier datasheet.

The molecular sieve line is the most-confused single entry on this table. A buyer who specifies "loss on drying less than 1.5 percent" on a molecular sieve PO is correct - that captures free moisture. A buyer who specifies "loss on ignition less than 1.5 percent" on the same PO will reject every shipment, because a properly activated 4A retains ~22 percent LOI as framework water. We have seen this exact mistake trigger a USD 18,000 claim on a 20-ton shipment of 4A; the dispute took 73 days to resolve.

The pseudo-boehmite line is the second-most-confused entry. Pseudo-boehmite (AlO(OH) center dot xH2O) is sold as a gel (water content 15-30 percent), as a spray-dried powder (water content 1-3 percent), and as a partially-aged intermediate (water content 5-12 percent). A buyer who specs "LOD less than 1.5 percent" on a gel-stage shipment is rejecting material that is correctly manufactured. A buyer who specs "LOI less than 25 percent" on a powder-stage shipment is rejecting correctly-dried material. The spec must match the supplied form.

5 Claim Mechanisms That Cost the Buyer More Than the Material

The 5 most common claim scenarios we see on activated alumina, molecular sieve, ATH, pseudo-boehmite, and tabular alumina POs. Each shows the typical magnitude of the dispute cost and the recovery path. The pattern is consistent: the ambiguity in the spec clause creates the dispute, not the quality of the material.

Claim 1: LOI Specified Where LOD Was Meant (and Vice Versa)

Mechanism: a buyer writes "loss on ignition less than 1.5 percent" on a molecular sieve 4A PO, when they meant "loss on drying less than 1.5 percent" to control free moisture. The first shipment shows LOI 22.4 percent (correctly activated 4A, ~22 percent framework water) and the buyer rejects the lot - the 22.4 percent LOI is correct chemistry, not a defect.

Typical claim size: USD 8,000-25,000 (one shipment + freight + handling). Recovery path: spec correction, supplier re-test at buyers cost, 14-45-day window. Prevention: the spec clause template in the next section names the standard, temperature, and typical range for the specific material.

Claim 2: Different Standards Cited by Buyer and Supplier

Mechanism: a buyer cites ASTM C25 (1000 degC); the supplier reports per ASTM D1209 (750 degC). The methods differ by 0.5-2.5 percent on ATH-containing materials; the buyer re-runs at 1000 degC, gets a higher number, and rejects.

Typical claim size: USD 5,000-15,000. Recovery: third-party referee (SGS, Bureau Veritas, or Intertek) at shared cost (USD 800-2,500 per test), 30-60 days. Prevention: cite the same standard by number, with temperature, so the standard cannot be substituted.

Claim 3: Outgassed vs Non-Outgassed LOI on Regenerated Catalyst Carrier

Mechanism: a buyer of regenerated (re-calcined) catalyst carrier accepts the first shipment at LOI 4.5 percent (typical for a properly regenerated carrier with surface -OH rehydrated to ~4 percent). Six months later, the same supplier ships a batch with LOI 2.1 percent (over-calcined, lower surface area, lower metal-dispersion capacity). The buyers incoming lab re-runs the test, gets 2.1 percent, and rejects the lot for "non-conforming LOI" - but the spec says "less than 5 percent" and 2.1 percent is technically passing. The dispute becomes "is the supplier shipping consistent product" rather than "is the product meeting spec".

Typical claim size: USD 12,000-40,000 (production-line disruption if the rejected lot blocks a campaign). Recovery: change-control, supplier investigation, 60-90 days. Prevention: tighten LOI to a narrower range (e.g., 3.5-5.5 percent for the regenerated carrier) and require SPC data on the last 5 batches.

Claim 4: "As Received" vs "Equilibrated" LOD

Mechanism: a buyer specs "LOD less than 1.0 percent" on a pseudo-boehmite PO. The supplier CoA reports LOD 0.8 percent "as received" - the powder was sealed in a moisture-proof bag at the manufacturing site and tested immediately. By the time the buyers incoming lab tests the same lot 30 days later (after sea freight and warehouse storage), LOD has climbed to 2.5 percent because the powder has equilibrated with ambient humidity (the bag was opened and re-closed during unloading). The buyer rejects the lot.

Typical claim size: USD 6,000-20,000. Recovery path: ambient-equilibration protocol (ASTM D280 specifies equilibration at 23 degC / 50 percent RH for 24 hours before LOD test), both labs re-test, 14-30-day resolution. Prevention: the spec clause should specify "LOD at 105 degC, 2 h, after 24 h equilibration at 23 degC / 50 percent RH" (the ASTM D280 reference condition) rather than "LOD less than 1.0 percent".

Claim 5: Hybrid Spec Combining LOI and LOD Limits Improperly

Mechanism: a buyer writes "LOI less than 5 percent AND LOD less than 0.5 percent" on an activated alumina PO. The supplier ships LOI 4.2 percent and LOD 0.8 percent; the buyer rejects for the LOD being over spec. The supplier argues the 0.5 percent LOD spec is unusual (industrial grade typically allows 1.0-2.0 percent). The dispute becomes "is the LOD spec realistic" rather than "is the material meeting spec".

Typical claim size: USD 4,000-15,000. Recovery path: spec waiver or first-article qualification, 30-60-day resolution. Prevention: spec the realistic range for the material and grade (industrial-grade activated alumina LOD is typically 0.5-2.0 percent, not 0.5 percent). The buyer should write "LOD less than 2.0 percent" if they want industrial-grade material.

5-Step Dispute Resolution Flow When the Numbers Disagree

When buyer and supplier both have valid CoAs that disagree, the 5-step flow that resolves 90 percent of disputes within 30 days:

Step 1: Spec audit. Both parties review the original specification clause and identify the cited standard, temperature, time, sample mass, atmosphere, and equilibration condition. If the spec is ambiguous (e.g., "low LOI" without a number), the buyer usually bears the burden of proving the material is non-conforming.

Step 2: Method audit. Both labs produce their full SOP, including sample preparation, equipment calibration, and reference-material verification. The most common cause of disagreement is a sample-preparation difference (e.g., buyer grinds to minus 75 micrometers before testing, supplier tests as-received).

Step 3: Sample exchange. Both labs test the same homogenized sample (prepared by splitting a sealed reference portion from the disputed lot). The result on the exchanged sample is the definitive value for the dispute. Cost: USD 200-500 per lab per test, 3-7 business days.

Step 4: Third-party referee. If steps 1-3 do not resolve, an independent lab (SGS, Bureau Veritas, Intertek) tests the exchanged sample. The referees result is binding under most industry standard contracts. Cost: USD 800-2,500 per test, 7-14 business days.

Step 5: Method harmonization. The buyer and supplier agree on the exact method (standard + sample prep + equilibration + reference material) for future shipments. The harmonized method is appended to the spec for the next PO cycle. Cost: zero direct, but the contract negotiation adds 30-60 days to the next PO.

The Spec Clause Template: Copy This Into Your Next RFQ

A specification clause that closes the LOI vs LOD ambiguity in 5 lines. The clause is appropriate for activated alumina, molecular sieve 4A/5A/13X, ATH, pseudo-boehmite (powder form), and tabular alumina. For gel-stage pseudo-boehmite, replace the LOD line with a solids-content line at 60-85 percent.

"Loss on Ignition (LOI): per ISO 3262-1, 1000 degC, 2 h, air atmosphere, sample mass 2 g, platinum crucible. Report mass loss to 0.01 percent. Target: [material-specific, see table above]."

"Loss on Drying (LOD): per ISO 787-2 / ASTM D280, 105 degC, 2 h, after 24 h equilibration at 23 degC / 50 percent RH, sample mass 5 g, glass weighing bottle. Report mass loss to 0.01 percent. Target: [material-specific, see table above]."

The 5 fields that matter in the clause are: standard number (so the method cannot be substituted), temperature (so the temperature cannot be substituted), time (so the endpoint cannot be shortened), sample mass + geometry (so the bed depth cannot be manipulated), and equilibration condition (so the LOD baseline is reproducible). Without these 5 fields, the spec is ambiguous and any dispute will be hard to resolve.

For molecular sieve 4A specifically, the clause must explicitly exclude LOI from the acceptance criterion, because LOI 22 percent is the correct chemistry for activated 4A. The clause for 4A is:

"Loss on Ignition (LOI) for Molecular Sieve 4A: per ISO 3262-1, 1000 degC, 2 h. Informational only - LOI 20-23 percent is correct for activated 4A and not an acceptance criterion."

"Loss on Drying (LOD) for Molecular Sieve 4A: per ISO 787-2, 105 degC, 2 h, after 24 h equilibration at 23 degC / 50 percent RH. Acceptance criterion: less than 1.5 percent by mass."

For pseudo-boehmite gel (water content 15-30 percent), the clause becomes a solids-content line:

"Solids content for Pseudo Boehmite Gel: per ISO 3251, 105 degC, 2 h, sample mass 5 g. Acceptance criterion: 70-85 percent by mass (informational only, not a rejection criterion)."

"Loss on Ignition (LOI) for Pseudo Boehmite Gel: per ISO 3262-1, 1000 degC, 2 h. Acceptance criterion: 20-30 percent by mass (captures total volatile content including structural water)."

5 Lab-Level Indicators That the CoA Was Generated Correctly

When you receive a CoA on an incoming shipment, these 5 indicators flag whether the LOI/LOD numbers were generated correctly:

1. Standard cited by number. "LOI per standard method" without a number is suspect - could be any temperature, any time.

2. Temperature stated explicitly (1000 degC LOI, 105 degC LOD). "High-temperature LOI" could be 750 or 1100 degC depending on method.

3. Sample mass reported (typically 1-5 g). Missing mass may indicate non-standard mass that affects the result.

4. Equilibration stated for LOD (23 degC / 50 percent RH / 24 h). Missing equilibration may mean "as received" with transit moisture.

5. Numbers physically plausible. LOI 0.5 percent on a 4A is wrong (should be 20-23 percent); LOD 5 percent on a powder-stage pseudo-boehmite is wrong (should be 1-3 percent). Ask for the lab SOP before accepting implausible values.

How LOI and LOD Map to Real Procurement Outcomes

The 4 procurement-side outcomes that LOI and LOD directly affect, beyond the obvious "rejection if out of spec":

Outcome 1: Lot-to-lot consistency in production. A supplier shipping LOI 3.5 percent on lot A and LOI 5.5 percent on lot B (both within 3-8 percent spec for activated alumina) may have an inconsistent calcination profile; the buyer sees a 5-10 percent swing in bed lifetime before breakthrough. Specifying a tighter LOI range (4.0-5.5 percent) reduces this swing.

Outcome 2: Freight cost. LOI is part of shipped mass for hydrated materials: 4A at 22 percent LOI ships 22 percent water at the buyers freight cost. Powder-stage pseudo-boehmite at 1-3 percent water saves 20+ percent of freight cost.

Outcome 3: Storage stability. High-LOD powder picks up additional moisture during storage if the bag is not perfectly sealed. A 1 percent LOD at the suppliers warehouse may become 1.5 percent at the buyers warehouse 90 days later. Specifying LOD at 24 h equilibration (not "as received") gives the buyer a stable baseline regardless of storage time.

Outcome 4: Application performance. The LOI of a catalyst carrier affects its metal-dispersion capacity (higher LOI = more surface -OH = better metal anchoring). The LOD of an activated alumina affects its initial water-uptake capacity (lower LOD = more capacity available). The LOI/LOD spec should be written to control the application outcome, not just a generic property.

Frequently Asked Questions

What is the difference between LOI and LOD on a Certificate of Analysis?

LOI (Loss on Ignition) is the mass loss after firing at 1000-1100 degC for 1-2 hours per ISO 3262-1 or ASTM C25. It captures chemically combined water, hydroxide decomposition, residual carbonates, and trace organics. LOD (Loss on Drying) is the mass loss after drying at 105 degC for 2 hours per ISO 787-2 or ASTM D280. It captures only free moisture (surface water, pore water, capillary water). The two numbers cannot be substituted because they measure different chemical species at different temperatures.

Why does my molecular sieve 4A show 22 percent LOI but only 1 percent LOD?

Molecular sieve 4A (Na12Al12Si12O48) binds ~22 percent water by mass in its framework after activation. The water is chemically combined with the sodium cations and is not removable by 105 degC drying. Firing at 1000 degC drives off all the framework water, giving LOI of 20-23 percent. A properly activated 4A should have LOD less than 1.5 percent (free moisture) and LOI of 20-23 percent (framework water). A CoA showing LOI less than 5 percent on a 4A indicates over-activation and reduced water capacity.

Can I specify LOD instead of LOI on a pseudo-boehmite PO to control water content?

No. Pseudo-boehmite (AlO(OH) center dot xH2O) gel contains 15-30 percent water by mass. Most of this water is structural (the OH groups in the boehmite layers), not free moisture. A 105 degC LOD removes only the free moisture (typically 5-15 percent on gel-stage pseudo-boehmite), not the structural water. To control the total water content of pseudo-boehmite, spec the solids content (per ISO 3251) or the LOI (per ISO 3262-1). LOD on pseudo-boehmite is a useful but limited control test.

What temperature does LOI use and why does it matter?

Standard LOI uses 1000-1100 degC for 1-2 hours. This temperature is high enough to fully decompose hydroxides (ATH decomposes at 200-600 degC, pseudo-boehmite at 400-700 degC, zeolite framework water at 200-900 degC) and to combust trace organics. A lower LOI temperature (e.g., 750-850 degC per ASTM D1209 for plastics) under-reports the volatile content of ATH-containing materials by 1-2 percent. A higher temperature (1100-1200 degC) is rarely used but gives the same result as 1000 degC for most alumina-based materials.

Why does my LOD value change between the suppliers CoA and my incoming lab?

The most common causes are (a) different equilibration conditions - the supplier tested "as received" (powder from a freshly sealed bag) while your lab tested after 30 days of warehouse storage (powder equilibrated to ambient humidity); (b) different sample mass - thin bed vs deep bed gives different LOD results; (c) different oven type - convection oven vs vacuum oven can differ by 0.2-0.5 percent. The fix is to specify the equilibration condition (23 degC / 50 percent RH / 24 h), sample mass, and oven type in the spec clause.

How do I write a spec clause that prevents LOI/LOD disputes?

Cite the standard by number (ISO 3262-1 for LOI, ISO 787-2 / ASTM D280 for LOD), state the temperature (1000 degC for LOI, 105 degC for LOD), state the time (typically 2 h), state the sample mass (typically 2-5 g), state the atmosphere (air for both), state the equilibration condition for LOD (23 degC / 50 percent RH / 24 h). With all 5 fields specified, the spec is unambiguous and the dispute surface drops to near zero. See the template clause earlier in this post.

What does ASTM D1209 LOI measure differently from ISO 3262-1?

ASTM D1209 is the plastics-industry LOI method, using 750-850 degC for 2 hours. ISO 3262-1 is the general (paint, ceramic) LOI method, using 1000 degC for 2 hours. On ATH-containing materials, the 250 degC gap changes the result by 1-2 percent because ATH decomposes progressively between 200-600 degC and is not fully decomposed at 750-850 degC. The two methods are not interchangeable for ATH-containing materials.

What is the typical LOI for activated alumina in industrial-grade vs desiccant-grade?

Industrial-grade activated alumina (used for dehydration, defluoridation, H2O2 service) typically shows LOI 3-6 percent and LOD 0.5-2.0 percent. Desiccant-grade activated alumina (used for compressed air drying, transformer breathers) typically shows LOI 5-8 percent and LOD 1.0-2.0 percent (higher surface -OH density for water adsorption). Specifying LOI 3-5 percent will bias the supply toward industrial grade; specifying LOI 5-8 percent will bias toward desiccant grade. The buyer should match the spec to the intended application.

Does LOI affect the metal-dispersion capacity of a catalyst carrier?

Yes. Higher LOI means more surface -OH groups remaining on the carrier after calcination, which provides more anchoring sites for active metals (Ni, Mo, Co, Pt). A carrier with LOI 4.5 percent will typically disperse 10-15 percent more active metal than a carrier with LOI 2.0 percent at the same metal loading. Specifying LOI 4.0-5.5 percent for an FCC or HDS catalyst carrier ensures consistent metal-dispersion capacity. Over-calcining (low LOI) reduces both dispersion and catalyst lifetime.

How does ambient humidity affect LOD during storage and shipping?

Activated alumina, molecular sieve, and pseudo-boehmite powders are hygroscopic. Exposed to 70-80 percent relative humidity (typical tropical warehouse conditions), activated alumina picks up 3-5 percent moisture over 30 days; molecular sieve picks up 15-20 percent over 30 days; pseudo-boehmite picks up 5-10 percent over 30 days. A CoA LOD value measured at the supplier is meaningful only if the powder has been stored in a sealed moisture-proof bag. The buyers incoming LOD depends on the storage and shipping history.

What is the difference between "as received" LOD and "equilibrated" LOD?

"As received" LOD tests the powder in whatever moisture state it arrives in - typically the suppliers freshly sealed bag. "Equilibrated" LOD (per ASTM D280) tests the powder after 24 hours at 23 degC / 50 percent RH - a controlled moisture baseline. Equilibrated LOD is reproducible across labs and time. As-received LOD is not reproducible because it depends on the shipping and storage history. Always specify equilibrated LOD in the spec clause; the supplier will report it consistently and the buyer will receive consistent results.

Can LOI be measured by thermogravimetric analysis (TGA) instead of muffle furnace?

Yes, and TGA is increasingly the preferred method for LOI on research-grade materials because it produces a continuous mass-loss curve (not just a single endpoint). The TGA method uses a 5-50 mg sample, a heating ramp of 5-10 K/min to 1000-1100 degC, and an air or nitrogen purge. The endpoint mass loss at 1000 degC is equivalent to the muffle-furnace LOI within 0.1-0.3 percent. The advantage is that the TGA curve shows the temperature at which each volatile species is released (e.g., free moisture at 100 degC, zeolite water at 200-400 degC, ATH decomposition at 300 degC), which helps interpret the LOI result. The disadvantage is the higher instrument cost and slower throughput.

Is LOI the same as ash content?

No, but they are often confused. LOI is the mass LOST on firing (the volatile species driven off); ash content is the mass that REMAINS after firing. For ATH (Al(OH)3), LOI is 34.6 percent (water driven off) and ash content is 65.4 percent (Al2O3 residue). For a polymeric material with 30 percent ATH filler, LOI is ~10 percent and ash content is ~30 percent plus any non-ATH residue. The two are complementary, not identical; the spec should use one based on what the buyer wants to control.

How AluminaWorld Reports LOI and LOD on Every Shipment

Our standard CoA for activated alumina, molecular sieve 4A/5A/13X, ATH, pseudo-boehmite (powder and gel), and tabular alumina includes both LOI (ISO 3262-1, 1000 degC, 2 h) and LOD (ISO 787-2, 105 degC, 2 h, 24 h equilibration at 23 degC / 50 percent RH), with standard, temperature, time, sample mass, atmosphere, and equilibration stated on every CoA.

For buyers wanting a tighter or different LOI range (e.g., 4.0-5.5 percent instead of 3-8 percent for activated alumina), we run a custom LOI protocol at no charge for orders above 5 MT per shipment, with the CoA reporting both custom and standard results.

For third-party referee testing on a disputed lot, we accept SGS, Bureau Veritas, and Intertek as binding referees with cost shared 50/50 if the third-party result is within 1.0 percent of the suppliers CoA; if more than 1.0 percent off, we pay full referee cost. Average resolution: 18 days (industry average 45-60 days).

For buyers writing a new spec clause, our technical team reviews the draft and flags ambiguities (LOI vs LOD, temperature mismatch, missing equilibration) within 24 hours, free of charge.

Internal Cross-References and Further Reading

This post closes the LOI vs LOD ambiguity at the spec-clause level. Related posts on the AluminaWorld technical blog cover the next-level QC topics:

For the surface-area side of the same CoA, see ISO 9277 BET vs Single-Point Method: Why Two Labs Report Different m2/g - the BET surface area is the second-most-common QC dispute, and the root cause (single-point vs multi-point BET, outgassing temperature, relative pressure range) is structurally similar to the LOI vs LOD story.

For the particle-size side of the CoA, see Alumina Powder Particle Size Distribution: Laser Diffraction vs Sedimentation - the laser-diffraction vs sedimentation method dispute is the third-most-common QC argument, and the resolution is the same: cite the standard by number, state the conditions, and require method disclosure on the CoA.

For the crush-strength side of the CoA, see Reading a Failed Crush-Strength Report: ASTM D4179 Outliers vs Genuine Batch Rejection - the crush-strength test has its own ambiguity (sample mass, sphere vs flat-plate geometry, loading rate), and the dispute resolution flow at the end of that post is the same template as this one.

For the broader procurement-side audit workflow, see How to Audit an Adsorbent Supplier Remotely: 12 Documents to Request Before the First PO - the audit checklist includes verifying the CoA protocol, the lab calibration, and the reference-material verification, all of which are the upstream causes of LOI/LOD disputes.

For the supplier-selection side (qualification cost vs stock-out risk), see Sole-Source vs Dual-Source Adsorbent Supply: Qualification Cost, Stock-Out Risk and Hidden Switching Cost Modelling - the qualification step is when the LOI/LOD spec clause is first agreed, and getting the clause right at qualification eliminates 90 percent of in-life disputes.

For the freight-cost impact of hydrated materials (high LOI = shipping water at the buyers freight cost), see Freight vs Density: Why Bulk Density Decides Your Landed Cost per Kg of Adsorption Capacity - the bulk-density angle adds another column to the LOI/LOD economics story.

Next Steps

For procurement engineers who want to tighten their next RFQ: send us your current adsorbent or alumina spec clause (even a one-page excerpt), and we will flag every LOI/LOD ambiguity and propose a tightened version within 24 hours. The service is free for orders above 1 MT per shipment.

For QC lab managers who want a copy of our standard CoA protocol: request it via WhatsApp or email and we will send the full SOP (sample prep, muffle furnace program, equilibration chamber spec, reference material list) plus the last 5 batches CoA values for any product in our catalog.

For technical teams who want to discuss a specific LOI/LOD dispute on a current shipment: call us with the disputed lot number, both CoAs, and the spec clause, and we will propose a 5-step resolution flow tailored to your case. Most disputes resolve inside 18 days when both parties accept the third-party referee flow.

WhatsApp: +86 133 2522 2240 (click to open WhatsApp with a prefilled message).
Email: barry@aluminaworld.com
Typical response time: under 4 hours during China business hours (UTC+8), under 24 hours otherwise.

For a downloadable spec clause template covering activated alumina, molecular sieve 4A/5A/13X, ATH, pseudo-boehmite, and tabular alumina with LOI/LOD fields pre-filled per material, request it via the same WhatsApp or email link above.