Heading 1520 covers glycerol whether or not pure, so crude glycerol waters, lyes, and refined pharmaceutical-grade glycerine all fall under subheading 152000. Purity does not change the HTS classification, but it is commercially and regulatorily significant: USP-grade glycerine used in drugs or food must meet FDA purity specifications, and the importer should obtain a certificate of analysis confirming grade to support both the entry and any downstream regulatory compliance.

No—the source process does not affect HTS classification. Both biodiesel-derived crude glycerol and soap-lye glycerol fall under heading 1520 as long as the product is glycerol (or glycerol water/lye) and has not been chemically converted into a derivative such as glycerol esters or ethers, which would move to other chapters. The entry documentation should describe the production method and purity level for CBP review.