Sourcing sulfolane from China

Sulfolane duty and suspension

Read from the UK Trade Tariff on 1 October 2026, heading 2934 covers nucleic acids and other heterocyclic compounds. Sulfolane is specifically listed as tetrahydrothiophene dioxide, chemical identity 126-33-0, under 2934 99 90 66. The supplied tariff data contains only this sulfolane-specific line. For the wider heading, see the thiophene guide.

For goods from China, this line has a 6% third-country duty and an autonomous suspension to 0%. Its footnote excludes mixtures, preparations and products containing different components. No anti-dumping or countervailing duty is recorded. The tariff also attaches dangerous-chemical and waste export controls. Ask your customs broker to confirm their relevance to the shipment and any applicable import requirements.

Give the broker the chemical identity, full composition and batch documents to confirm the commodity code. Have suspension eligibility checked before using zero duty in a budget. The hypothetical order is illustrative, rather than a quotation; its duty depends on whether the suspension applies.

Specify sulfolane composition and batch quality

Specify sulfolane by chemical identity 126-33-0. State whether the order is the single substance or a water-containing formulation, and whether virgin or recovered material is acceptable. Agree assay, water content, acidity, colour and impurity acceptance criteria with the testing methods. Ask for a batch certificate of analysis and retain an approved sample.

For Great Britain, confirm with HSE whether annual imports of the substance need UK REACH registration coverage or can be covered by an appropriate only-representative arrangement. Chemical suppliers, including importers, are responsible for classification. A safety data sheet is required when a hazardous chemical is supplied for use at work. Request an English safety data sheet for the actual composition ordered.

Worked duty example

Illustrative example, not a quote: Illustrative order: 5 tonnes of neat sulfolane; confirm suspension eligibility under 2934 99 90 66, invoiced at £15,000 free on board, with £1,500 of freight and insurance to the UK. The customs value is £16,500. Duty at 6% is £990. Import VAT at 20% is charged on the customs value plus duty, £17,490, so it is £3,498. Import taxes total £4,488; a VAT-registered importer can usually reclaim the VAT, so the lasting cost is the £990 of duty. The import duty and VAT guide explains each step.

Inspection checklist

Identity: match the drum labels, batch certificate and purchase specification to sulfolane and chemical identity 126-33-0.

Composition: test assay and water content against the agreed methods; check that a neat-substance order has not been replaced by a formulated blend.

Batch quality: compare acidity, colour and impurity results with the approved sample; retain a sealed arrival sample for investigating discrepancies.

Packing: inspect drum seals, leaks, corrosion and batch markings; reconcile the delivered material with its safety data sheet before releasing it for use.

What goes wrong

A sulfolane certificate can report acceptable assay while leaving water content or acidity unclear. Recovered material may also differ from the approved sample. Specify separate acceptance criteria instead of accepting a general purity claim, and investigate any batch change before introducing the material into your process.

A formulation can also be budgeted as if it qualified for the neat-substance tariff suspension. Keep the composition and customs documents aligned. HSE requires annual quantity reporting for importers of PIC-listed chemicals; have the exact substance checked before assuming this applies. Waste shipment controls apply only to material that is waste, so confirm the status of spent solvent with your broker before shipment.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For repeat volumes, see container programmes.