Sourcing Isobutylene from China

Isobutylene duty and tariff scope

Read from the UK Trade Tariff on 1 October 2026, isobutylene falls within heading 2901, acyclic hydrocarbons, under 2901 23 00 00 for butene and its isomers. The supply grades shown share this tariff line; they are purchasing descriptions rather than separate commodity codes. See the wider acyclic hydrocarbons guide.

The recorded duty for goods from China is 0%, with no anti-dumping or countervailing duty and no suspension listed. The attached measure is labelled Export control - Waste. Ask your customs broker to confirm its relevance if the material is waste or a return shipment; the supplied record identifies an export control rather than an import control.

Confirm the commodity code against the actual composition and batch certificate, especially for mixtures offered as isobutylene. Keep the chemical identity consistent across the purchase specification, invoice and safety documents.

Specify isobutylene purity and gas connections

Specify isobutylene content separately from total hydrocarbon content. Agree limits for other butenes, butanes, water and sulphur compounds, with the analytical method and a certificate of analysis for each batch. State the intended process so the supplier can identify any additives and explain whether the offered material suits that use.

Agree the cylinder or tank arrangement, valve connection, withdrawal method and return arrangements before ordering. If importing one tonne or more annually, confirm with HSE whether UK REACH registration or only-representative coverage is required for your imports. Hazardous chemicals supplied for workplace use require a safety data sheet, and chemicals must be correctly labelled and packaged before being placed on the market. Dangerous goods sent by sea require a dangerous goods notification.

Worked duty example

Illustrative example, not a quote: Illustrative batch of isobutylene in returnable cylinders for a specialist chemical business under 2901 23 00 00, invoiced at £21,000 free on board, with £3,200 of freight and insurance to the UK. The customs value is £24,200. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £24,200, so it is £4,840. With no duty, the only import tax is the VAT, which a VAT-registered importer can usually reclaim. The import duty and VAT guide explains each step.

Inspection checklist

Identity and purity: compare the batch certificate with the order and arrange gas chromatography through a laboratory equipped to sample pressurised gas.

Contamination: check the agreed water, sulphur and other hydrocarbon results, together with previous contents and cleaning records for reused containers.

Containment: check cylinder or tank identifiers, seals, visible damage, valve protection and compatibility with the receiving equipment before connection.

Documents: match the batch identifiers across the certificate, safety data sheet, labels and sea transport notification. Use the inspection guide to agree the inspection scope.

What goes wrong

A total hydrocarbon result can conceal insufficient isobutylene content. Other butenes or butanes may meet a generic supplier description while failing your process specification. Moisture or residues from reused containers can also cause an otherwise acceptable batch to fail the agreed checks.

Gas can arrive in containers with incompatible valves or without the agreed batch documents. Set the acceptance criteria before loading, arrange specialist sampling and resolve connection details with the receiving site. Treat the illustrative order values as calculation inputs, not a supplier quotation.

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.