bleaching earth
Noun: - An adsorbent clay that removes coloring from oils: Bleaching earth is a type of clay, often activated, with strong adsorptive properties. It is used primarily in industrial processes to purify, decolorize, and remove impurities from various oils, fats, and waxes.
Bleaching earth is used as a processing material. It is typically mixed with a raw oil, heated, and then filtered out, taking unwanted color bodies and other impurities with it. - The primary function of bleaching earth is to adsorb (not absorb) pigments and contaminants. - It is a material or substance, not an action.
- The vegetable oil was clarified by passing it through bleaching earth.
- The refinery ordered several tons of activated bleaching earth for its purification tanks.
- The effectiveness of the bleaching earth was measured by the color reduction in the final product.
- "Activated bleaching earth": A common variant where the clay has been treated with acid to increase its surface area and adsorptive capacity.
- Activated bleaching earth is essential for producing high-quality, clear lubricating oils.
- Bleaching clay (n): A direct synonym for bleaching earth.
- Fuller's earth (n): A historical and sometimes overlapping term for an absorbent clay used in cleaning and decolorizing; not all Fuller's earth is used for bleaching, and not all bleaching earth is Fuller's earth.
- Adsorbent (n/adj): A general term for a material that causes adsorption. Bleaching earth is a specific type of adsorbent.
- Decolorizing clay
- Adsorptive clay
- Purifying clay
This term is highly technical and specific to industrial chemistry, refining, and oil processing contexts. It does not refer to the planet's soil or to any action (like the verb "to bleach"). Its core meaning is inextricably linked to its function of adsorptive decolorization.
- an adsorbent clay that will remove coloring from oils