Type a chemical, a CAS number or a product code, and Sourzi puts every check it can run on one card: the chemical register, the duty, anti dumping cases and the supplier.
Each row shows the official file it came from and the date of that file. Where Sourzi does not hold the answer, the row says so instead of guessing.
China to the United States
Potassium carbonate
CAS 584-08-7 · Product code 2836.40.00 · Full CAS page
One row needs a check before you order, and 2 rows are gaps Sourzi cannot fill yet.
TSCA (US register)
Listed
CAS 584-08-7 is on the TSCA inventory (ACTIVE), the US chemical register.
Product code 28364000 has no line in the stored US tariff file, which covers chapters 28 to 39.
USITC tariff extract · file dated 25 Sep 2026
Section 301 (China)
Not stored
Sourzi does not store the Section 301 rate on goods of China yet, so this row is a gap, not a guess. Confirm the rate with your customs broker before you price the order. No stored Section 301 exclusion matches this code.
US anti dumping or countervailing cases on goods of China are stored under heading 2836: A-570-880. A heading match is not a scope ruling, and the rate depends on the producer. Check the case on ACCESS before you order.
Add the supplier's company name to screen it against the DFAT sanctions list and the US UFLPA Entity List.
Watch Potassium carbonate
Duty rates, anti dumping cases and register listings change after you have checked them once. Sourzi is building a daily watch that emails you the day a row on this card changes.
Leave your email and you get one message when the watch is live for Potassium carbonate, and nothing else.
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