Chapter 2522 — Customs Tariff Headings

Agricultural Quicklime Soil Amendment

Agricultural quicklime in pebble form, produced by calcining limestone, used to correct soil pH and supplement magnesium in acidic farm fields. It is in the crude or processed state permitted by Chapter 25 and is not roasted, calcined beyond the heading's scope, or mixed, so it falls under tariff item 2522.10.00.

Chemical Manufacturing Quicklime

Technical grade quicklime in lump form, used as feedstock for producing calcium carbide and other organometallic compounds. It is obtained by calcining limestone and has not undergone processing beyond that allowed in Chapter 25, so it is classified as quicklime under 2522.10.00.

Construction Quicklime for Mortar

High-reactivity quicklime in pebble form, intended for slaking into lime putty for traditional masonry mortars and plasters. It is quicklime as defined in heading 25.22, not hydraulic or slaked lime, and is not processed beyond crushing or grinding, so it falls under 2522.10.00.

Gold Mining Quicklime

Lump quicklime used in gold mining cyanidation processes to provide alkaline conditions for ore processing. It is unhydrated quicklime derived from limestone calcination, with no processing beyond the mechanical processes allowed in Chapter 25, so it is classified under 2522.10.00.

Industrial Quicklime Powder

High-calcium quicklime in fine powder form, produced by calcining limestone and used in steelmaking for slag formation and impurity removal. It is quicklime under heading 25.22, and powdering is a permitted mechanical process, so it falls under 2522.10.00.

Metallurgical Grade Quicklime

Coarse quicklime lumps graded for use in blast furnaces and steel desulfurization processes. It is unslaked quicklime from high-purity limestone calcination, with no processing beyond crushing or sizing, so it is classified under 2522.10.00.

Paper Industry Quicklime

Reactive quicklime powder used in kraft pulping for caustic recovery cycles and brightness control. It is quicklime from limestone calcination, and powdering is a permitted process, so it falls under 2522.10.00.

Water Treatment Quicklime

Fine-ground quicklime optimized for pH adjustment and softening in municipal water purification plants. It is mineral-derived quicklime, not a precipitated chemical, and grinding is a permitted mechanical process, so it is classified under 2522.10.00.

Agricultural Hydrated Lime for Soil pH Adjustment

Agricultural hydrated lime is a coarse slaked lime product produced by reacting quicklime with water, used to raise soil pH and supply calcium for crop growth. It falls under tariff item 2522.20.00 as slaked lime, distinct from fertilizers of Chapter 31, and is not processed beyond hydration.

Dolomitic Hydrated Lime

Dolomitic hydrated lime is produced by partially slaking dolomitic quicklime, containing both calcium and magnesium hydroxides. It is classified under tariff item 2522.20.00 as slaked lime, and is not excluded by Chapter 25 notes since it is not a pure calcium oxide or hydroxide of heading 28.25.

Flue Gas Desulfurization Slaked Lime

Flue gas desulfurization slaked lime is a reactive hydrated lime used in scrubbers to remove sulfur dioxide from power plant emissions. It is classified under tariff item 2522.20.00 as slaked lime, provided it is not mixed with other chemical additives that would change its classification.

Food-Grade Slaked Lime for Tortilla Production

Food-grade slaked lime is high-purity calcium hydroxide used in nixtamalization for tortilla production. It is classified under tariff item 2522.20.00 as slaked lime, and is not excluded by Chapter 25 notes despite its food-contact use, as it is not a medicament or cosmetic product.

Hydrated Lime Powder for Construction

Hydrated lime powder for construction is finely ground slaked lime produced by hydrating quicklime, used in mortar and plaster. It is classified under tariff item 2522.20.00 as slaked lime, and is not excluded by Chapter 25 notes since it is not processed beyond hydration and grinding.

Limewash Paint Base Slaked Lime

Limewash paint base slaked lime is a pure slaked lime product in powder or putty form, intended for mixing with pigments to create breathable coatings. It is classified under tariff item 2522.20.00 as slaked lime, and is not excluded by Chapter 25 notes as it is not a prepared paint of Chapter 32.

Slaked Lime Putty for Plastering

Slaked lime putty is a wet, aged paste of calcium hydroxide used in traditional lime plaster and decorative finishes. It is classified under tariff item 2522.20.00 as slaked lime, and is not excluded by Chapter 25 notes as it is not processed beyond hydration, despite its high water content.

Water Treatment Slaked Lime

Water treatment slaked lime is a high-calcium hydrated lime powder used for pH control, softening, and impurity removal in municipal water treatment. It is classified under tariff item 2522.20.00 as slaked lime, and is not excluded by Chapter 25 notes as it is not a synthetic hydroxide of heading 28.25.

Emoder Natural Hydraulic Lime

Emoder Natural Hydraulic Lime is a commercial-grade hydraulic lime produced by calcining marlstone, which contains natural clay impurities that impart hydraulic properties. It is used in conservation projects for pointing and rendering, where it cures effectively in damp conditions. This product falls under tariff item 2522.30.00 as it is a hydraulic lime, distinct from quicklime or slaked lime.

Hotkin Natural Hydraulic Lime NHL 5

Hotkin Natural Hydraulic Lime NHL 5 is an eminently hydraulic lime made from silica-rich limestone, providing high strength for structural mortars and hydraulic renders. It hardens through both carbonation and hydration, making it suitable for demanding applications. This product is classified under tariff item 2522.30.00 as a hydraulic lime, not a quicklime or slaked lime.

Natural Hydraulic Lime NHL 2

Natural Hydraulic Lime NHL 2 is a powdered binder made from limestone with natural silica and alumina impurities, calcined to develop hydraulic properties. It sets and hardens through a chemical reaction with water, making it suitable for lime mortars in restoration. This product is classified under tariff item 2522.30.00 as hydraulic lime, distinct from non-hydraulic limes.

Natural Hydraulic Lime NHL 3.5

Natural Hydraulic Lime NHL 3.5 is a moderately hydraulic lime derived from argillaceous limestone, fired at low temperatures to retain pozzolanic reactivity. It offers balanced strength for lime mortars in masonry restoration and breathable plasters. This product is classified under tariff item 2522.30.00 as hydraulic lime, which is a distinct category from quicklime and slaked lime.