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Sulphur stockpile being loaded at a port

Sulphur · UN 1350

A recovered by-product moving on an involuntary supply curve

Elemental sulphur trading, specification control and safe carriage, as a dedicated marketing and logistics discipline.

Market structure

Why sulphur behaves unlike any other traded commodity

Supply follows refining and gas throughput, not sulphur demand. Demand is agricultural. Sulphur price cycles therefore decouple from crude.

Estimated world production, 2024
85 Mt

USGS Mining Review, May 2025

US recovered sulphur, Jan–Nov 2025
6.82 Mt

4% lower than the same period in 2024. USGS

Seaborne export origins

  • Middle East, which dominates global seaborne supply
  • Vancouver, Canadian west coast
  • Black Sea and Baltic Sea
  • US Gulf and US West Coast

Primary demand regions

  • China: cfr China granular is a key global reference price
  • India
  • Morocco and Tunisia, for North African phosphate
  • Brazil

Largest end use

Sulphuric acid manufacture

Primarily for phosphate fertilizer production: DAP, MAP and SSP. This links sulphur demand to global agriculture rather than to energy.

Sources: USGS Mineral Industry Surveys · USGS Sulfur Statistics · Argus Sulphur Methodology

Traded product forms

Each form carries its own handling regime and price assessment

Granular sulphur held in a gloved hand
Form 01 · Granular
ParameterSpecification
Purity, dry basis99.5% min
Ash0.05% max
Moisture0.50% max

The principal internationally traded form. Conditioned for reduced dust and friability, enabling long-haul dry-bulk shipment and repeated handling.

Form 02 · Crushed lump
ParameterSpecification
Purity, dry basis99.5% min
Ash0.05% max
Moisture0.50% max

Broken from block or vat-poured sulphur and assessed separately from granular. Higher dust generation on handling.

Form 03 · Molten
ParameterSpecification
Purity, elemental S99.9%
Moisture0.5% max
Reduced carbon0.1% max
Ash0.01% max
As / Se / Te, each< 0.1 ppm

The highest-purity traded grade, moving by barge, pipeline and road tanker over shorter distances.

Specification values are the published product specifications used by Argus Media for its international sulphur price assessments. Source: Argus Sulphur Methodology and Specifications Guide.

Quality & test methods

What is certified, how it is measured, and what the numbers mean

Physical properties: formed sulphur lumps, IMSBC Code
PropertyValue
Bulk density1,053 – 1,176 kg/m³
Stowage factor0.85 – 0.95 m³/t
UN numberUN 1350
IMDG hazard classClass 4.1, flammable solid
Subsidiary hazardNone applicable
IMSBC groupGroup B, chemical hazard

Why specification discipline decides the trade

  • Moisture drives both weight settlement and corrosion risk: wet residues form sulphurous acid.
  • Ash and reduced carbon determine acceptability as sulphuric-acid plant feedstock.
  • Arsenic, selenium and tellurium matter to catalyst life in downstream acid plants, hence molten limits below 0.1 ppm each.
  • Purity on a dry basis is the contractual quality anchor at 99.5% minimum for solid forms.
Analytical test methods referenced in contracts
MethodWhat it measures
ASTM D4239Sulphur in coal and coke by high-temperature tube furnace combustion.
ASTM D2622Total sulphur in liquid petroleum and petroleum products by wavelength-dispersive X-ray fluorescence.
ASTM D7039Sulphur in petroleum products by monochromatic wavelength-dispersive XRF.
ASTM D5453Total sulphur in light hydrocarbons, motor fuels and oils by ultraviolet fluorescence.

Sources: IMO IMSBC Code, SULPHUR UN 1350 · ASTM International · Argus Sulphur Methodology

Price benchmarks

Published references against which cargoes are negotiated

Middle East posted prices as at February 2026. These figures are historic reference points, not current offers.

ADNOC · fob Ruwais
US$530/t

+US$10 vs January. OSP for the Indian subcontinent

KPC · fob Kuwait
US$520/t

+US$4 vs January. Kuwait Sulphur Price

QatarEnergy · fob Ras Laffan
US$520/t

+US$3 vs January. Qatar Sulphur Price

Spot

Cargoes sold to load within 40 days of the sale being agreed.

Contract

Volume contracted over a minimum three-month shipping period.

Formula

A pre-agreed calculation using published prices, applied to future deliveries.

Published assessment coverage
BasisCoverage
FOBVancouver, Middle East (excluding Iran), US Gulf, US West Coast, Black Sea, Baltic Sea. Iran is published separately as fob Iran, lump-granular.
CFRChina (granular, and molten-lump-granular), India, Brazil, North Africa.
CPTEurope: one assessment covering road-tanker trade.
FreightApproximately 16 route assessments including Vancouver–China, Middle East–East Coast India, US Gulf–Brazil and Baltic–Brazil.

Sources: World Fertilizer, citing Argus Media (February 2026 assessments) · Argus Sulphur Methodology

Safe carriage

IMSBC Code requirements for SULPHUR, UN 1350

Hazard 01

Dust explosion

Greatest during loading, unloading and hold cleaning. Ventilators need spark-arresting screens, and unsuitable electrical circuits must be isolated.

Hazard 02

Toxic gas on combustion

Burning sulphur evolves sulphur dioxide. Batten down and use the ship's fixed fire-fighting installation. Do not use water.

Hazard 03

Acid corrosion

Wet dust or residues form highly corrosive sulphurous acid. Tank tops and trim plates must be lime-washed or painted, and bilges pumped regularly.

Hazard 04

Segregation & response

Stow "separated from" foodstuffs. First aid follows the IMO MFAG. Fine grained sulphur and flowers of sulphur must not be carried in bulk at all.

Sulphur loading into a bulk carrier hold

Cargo sizing

  • Middle East solid sulphur trade is handled largely in 30,000 – 50,000 t vessels.
  • Mediterranean cargo sizes typically fall under 10,000 t.
  • European molten sulphur moves by barge, pipeline and road tanker, typically 5,000 – 10,000 t.

Sources: IMO IMSBC Code, SULPHUR (UN 1350) · UK P&I Club, Carefully to Carry 2023 · Argus Sulphur Methodology

Contract mechanics

How a sulphur cargo is structured, settled and evidenced

  1. 01

    Pricing basis

    • FOB in export regions; CFR in destination markets
    • Spot for cargoes loading within 40 days
    • Contract over a minimum three-month shipping period
    • Formula pricing referencing published assessments
  2. 02

    Vessel & lot

    • Handysize to panamax dry bulk carriers
    • Middle East trade largely in 30,000–50,000 t vessels
    • Minimum 10,000 t for inclusion in international assessments
    • Freight assessed across roughly 16 published routes
  3. 03

    Quality & quantity

    • Independent inspection by SGS, Bureau Veritas or Intertek
    • Certificate of analysis against the contractual specification
    • Weight certificate at load port
    • Moisture determination affecting settled weight
  4. 04

    Settlement

    • Most transactions on a sight or cash basis
    • Where credit terms apply, up to 180 days, the cost is subtracted from the published price
    • Documentary credits governed by ICC UCP 600

Documentary requirements

  • Bill of lading
  • Certificate of origin
  • Certificate of analysis against the contract specification
  • Weight certificate and independent inspection report
  • Letter of credit documentation under ICC UCP 600

Incoterms applied

  • FOB: seller places cargo on board the buyer's nominated vessel
  • CFR / CIF: seller pays freight; CIF adds marine insurance
  • DAP: delivered ready for unloading at the named place
  • CPT: used for European road-tanker trade

Producer terms

ADNOC publishes General Terms and Conditions for the Sale of Sulphur (July 2021 edition), which confirms a price-differential mechanism relative to market price.

Sources: Argus Sulphur Methodology · ICC Incoterms 2020 and UCP 600 · ADNOC GTC for Sale of Sulphur