Differences between Crude Glycerin, Technical Grade Glycerin, and USP Grade Glycerin
| Properties | Crude Glycerin | Technical Grade Glycerin | 99.7 -USP Grade Glycerin |
| Glycerol Content | 40 – 88% | 98.0 Min | 99.70% |
| Ash | 2.0% Max | N/A | N/A |
| Moisture Content | N/A | 2.0% Max | 0.3% Max |
| Chlorides | N/A | 10 ppm Max | 10 ppm Max |
| Color | N/A | 40 Max (Pt – Co) | 10 Max. (APHA) |
| Specific Gravity | N/A | 1.262 (@25C) | 1.2612 Min |
| Sulfate | N/A | N/A | 20 ppm Max |
| Assay | N/A | N/A | 99.0 – 101.0% (on dry basis) |
| Heavy Metals | N/A | 5 ppm Max | 5 ppm Max |
| Chlorinated Compounds | N/A | 30 ppm Max | 30 ppm Max |
| Residue on Ignition | N/A | N/A | 100 ppm Max |
| Fatty Acid & Ester | N/A | 1.00 Max | 1.000 Max |
| Water | 12.0% Max | 5.0% Max | 0.5% Max |
| pH (10% Solution) | 4.0 – 9.0 | 4.0 – 9.1 | N/A |
| DEG and Related Compounds | N/A | N/A | Pass |
| Organic Volatile Impurities | N/A | N/A | Pass |
| Organic Residue | 2.0% Max | 2.0% Max | N/A |
Crude Glycerin – Crude glycerin contains a significant amount of methanol, water, soaps, and salts and typically has a glycerol content of anywhere between 40 to 88%. Crude glycerol is a natural by-product produced during the biodiesel production process, specifically taking place during transesterification.
Technical Grade Glycerin – Technical grade glycerin is a refined, high-purity product that is water white with most of its contaminants completely removed. Technical grade glycerin contains no methanol, soaps, salts, and other foreign matter.
USP Grade Glycerin – USP Grade Glycerin is a pharmaceutical grade glycerin suitable for food, personal care, cosmetics, pharmaceuticals, and other specialty applications. All of these products have met the US Pharmacopeia specifications (USP 30).
PLEASE NOTE: Be leery of any company claiming to produce USP Grade glycerin as these companies MUST be registered and controlled by the FDA. Many companies make false claims of producing USP grade glycerin when in fact, they cannot and should not make such claims without being governed by the Federal Government.
