HS code · 6-digit subheading
HS Code 3815.90 – Reaction initiators, reaction accelerators and catalytic preparations, unsupported, n.e.c. or included
HS code 3815.90 is the 6-digit subheading for reaction initiators, reaction accelerators and catalytic preparations, unsupported, n.e.c. or included. It is used for polymerization initiators, vulcanization accelerators, hydrogenation catalysts, oxidation catalysts and esterification catalysts.
What HS 3815.90 covers
This HS code encompasses a broad range of chemical preparations that initiate, accelerate, or facilitate chemical reactions, but are not supported on a substrate and are not elsewhere specified. These are critical components in various industrial processes, including polymer manufacturing, pharmaceutical synthesis, and fine chemical production. Major importers and exporters are large chemical companies, specialized manufacturers, and research institutions globally. The trade in these goods is driven by demand for increased efficiency, selectivity, and sustainability in chemical processes. Key considerations include their specific catalytic activity, stability, and often proprietary formulations, which can significantly impact production costs and product quality in downstream industries.
- Covers
- Polymerization initiators
- Vulcanization accelerators
- Hydrogenation catalysts
- Oxidation catalysts
- Esterification catalysts
- Cross-linking agents
- Curing agents
- Examples
- BASF catalysts
- Evonik catalysts
- Johnson Matthey catalysts
- Arkema initiators
- Clariant catalysts
Codes often confused with 3815.90
Common mistake. This code can be confused with supported catalysts (38151X) or specific pure chemical compounds (Chapter 28 or 29) if the 'preparation' aspect and 'unsupported' nature are not clearly defined. It's crucial to distinguish between a single chemical and a formulated mixture for catalytic purposes.
Top exporters and importers of HS code 381590, 2025
In 2025, the largest exporter of HS code 381590 in UN Comtrade data was the United States, with 26% of world exports; the largest importer in UN Comtrade data was Thailand, with 8.6% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Top exporters 2025 · share of world exports
- 1 United States $1.2B 26% of world exports
- 2 Germany $1.0B 23% of world exports
- 3 Japan $431M 9.5% of world exports
World total: $4.6B Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 Thailand $417M 8.6% of world imports
- 2 South Korea $337M 6.9% of world imports
- 3 China $335M 6.9% of world imports
World total: $4.9B Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries that did not report are estimated from what other countries recorded trading with them. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM codes for 3815.90 5
Brazil splits HS 3815.90 into 5 NCM codes, Mercosur's 8-digit tariff lines.
- 3815.90.10 Petroleum cracking catalystsPara craqueamento de petróleo
- 3815.90.9 OtherOutros Group
- 3815.90.91 Isoprenylaluminium (IPRA) catalystsTendo como substância ativa o isoprenilalumínio (IPRA)
- 3815.90.92 Zinc oxide catalystsTendo como substância ativa o óxido de zinco
- 3815.90.93 Rare-earth oxide catalystsTendo como substância ativa óxidos de terras raras
- 3815.90.99 Other reaction initiators and catalystsOutros
All Brazil NCM codes in heading 38.15 →
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text is official; the English is our translation.
Questions about HS 3815.90
What is HS code 381590?
HS code 381590 is a 6-digit subheading in the Harmonized System that covers: Reaction initiators, reaction accelerators and catalytic preparations, unsupported, n.e.c. or included. This HS code encompasses a broad range of chemical preparations that initiate, accelerate, or facilitate chemical reactions, but are not supported on a substrate and are not elsewhere specified. These are critical components in various industrial processes, including polymer manufacturing, pharmaceutical synthesis, and fine chemical production. Major importers and exporters are large chemical companies, specialized manufacturers, and research institutions globally. The trade in these goods is driven by demand for increased efficiency, selectivity, and sustainability in chemical processes. Key considerations include their specific catalytic activity, stability, and often proprietary formulations, which can significantly impact production costs and product quality in downstream industries.
What products fall under HS code 381590?
Polymerization initiators, vulcanization accelerators, hydrogenation catalysts, oxidation catalysts, esterification catalysts, cross-linking agents, curing agents
What are common misclassifications for HS code 381590?
This code can be confused with supported catalysts (38151X) or specific pure chemical compounds (Chapter 28 or 29) if the 'preparation' aspect and 'unsupported' nature are not clearly defined. It's crucial to distinguish between a single chemical and a formulated mixture for catalytic purposes.
Which countries are the top exporters of goods under HS code 381590?
In 2025, the top exporters of HS code 381590 in UN Comtrade data were the United States ($1.2B, 26% of world exports), Germany ($1.0B) and Japan ($431M). World exports came to about $4.6B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Which countries are the top importers of goods under HS code 381590?
In 2025, the top importers of HS code 381590 in UN Comtrade data were Thailand ($417M, 8.6% of world imports), South Korea ($337M) and China ($335M). World imports came to about $4.9B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
How is HS code 381590 structured?
HS code 381590 is a 6-digit subheading under the Harmonized System. The first 2 digits (38) identify the chapter, digits 3-4 (15) identify the heading, and digits 5-6 (90) specify the subheading. This code is standardized globally by the World Customs Organization.
What is the Brazil NCM code for HS code 381590?
Brazil splits HS code 381590 into 5 NCM codes: 3815.90.10 (Petroleum cracking catalysts), 3815.90.91 (Isoprenylaluminium (IPRA) catalysts), 3815.90.92 (Zinc oxide catalysts), 3815.90.93 (Rare-earth oxide catalysts), 3815.90.99 (Other reaction initiators and catalysts). The first 6 digits of each match the HS code.