Glycerin Specifications
What are the differences between Crude Glycerin, Technical Grade Glycerin, and USP Grade Glycerin? What are the Glycerin Specifications?
| 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 typically contains significant amounts of methanol, water, soaps, and salts. Its glycerol content usually ranges from 40% to 88%. Most crude glycerin is a natural by-product of biodiesel production, specifically from the transesterification process. Therefore, crude glycerin often requires further refinement to meet specific uses or standards.
Technical Grade Glycerin
In contrast, technical grade glycerin requires a more refined, high-purity product. It is typically water-white, with most contaminants completely removed. Unlike crude glycerin, technical grade glycerin contains no methanol, soaps, salts, or other foreign materials. Notably, SRS International biodiesel plants, unlike many competitors, produce technical grade glycerin right from the start, ensuring a high-quality product.
USP Grade Glycerin
USP Grade Glycerin is a pharmaceutical-grade product that meets stringent US Pharmacopeia (USP 30) specifications. It is suitable for use in food, personal care, cosmetics, pharmaceuticals, and other specialty applications. This grade of glycerin is highly purified to meet the rigorous standards required in these industries.
Important Note
It is essential to be cautious when dealing with companies claiming to produce USP Grade glycerin. These companies must be FDA-registered and regulated. Many businesses falsely claim to produce USP-grade glycerin despite not meeting the necessary regulatory requirements. Therefore, it is crucial to verify the legitimacy of such claims to avoid purchasing substandard products.
By focusing on these distinctions, you can better understand the varying grades of glycerin and ensure that the products meet your specific needs.
WHAT CLASSIFIES GLYCERIN AS USP GRADE?
To be called USP Grade Glycerin, companies must adhere to strict regulations regarding their manufacturing facilities, testing methods, inspections, distribution, and warehousing. Indeed, true USP Grade Glycerin follows rules and guidelines set forth by the FDA. Specifically, the FDA requires all domestic companies distributing USP Grade Glycerin to be registered and listed, unless they qualify for an exemption. Furthermore, the same regulations apply to USP Glycerin originating from a foreign manufacturing facility and being imported into the United States. In this case, FDA compliance is required by both the foreign manufacturer and the importer.
Moreover, FDA regulations mandate systematic and thorough record keeping by all USP glycerin manufacturers. These companies must maintain supported documentation for every shipment, including lot numbers and permits, to trace the product back to its production plant. This ensures transparency and accountability throughout the supply chain.
USP Grade Glycerin assures buyers of the product’s integrity, which cannot be achieved through physical and chemical testing alone. In contrast, Technical Grade Glycerin is not subject to such stringent governmental regulatory control. Although it is produced through similar processes, Technical Grade Glycerin does not need to meet the requirements of USP or FCC, nor does it need to comply with FDA regulations. Instead, this grade of glycerin only needs to meet the specifications mutually agreed upon by the buyer and seller.
In conclusion, while USP Grade Glycerin offers the assurance of compliance with rigorous standards, Technical Grade Glycerin offers more flexibility in its production and distribution. Therefore, understanding these differences is essential when selecting the right grade for your needs.
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