Industrial chemicals · Taylor, TXCertificate of Analysis
Sample Certificate of Analysis
Propylene Glycol 50% – USP Grade (C3H8O2)
USP Grade · 50%
Sample COA. Contact Alliance Chemical with your lot number to request a lot-specific COA.
Last reviewed 2026-07-06 by Andre Taki, DOT Hazmat Specialist.
COA · Answer summary
Sample specification reference for Propylene Glycol 50% – USP Grade (C3H8O2). Source-record results are reference values, not measurements for your lot.
- Assay specification
- 49.0 - 51.0 %, by volume
- Grade
- USP Grade
Specifications
| Parameter | Specification | Source reference result | Test Method |
|---|---|---|---|
| Assay | 49.0 - 51.0 %, by volume | 50.0 % | — |
| Propylene glycol concentration | 49.0 - 51.0 % v/v | 50.0 % | — |
| Dilution water | Purified Water USP; conductivity ≤ 1.3 µS/cm @ 25 °C | Passes test | USP <1231> / conductivity USP <645> |
| Acidity | not more than 0.10 mL of 0.10 N sodium hydroxide | 0.02 | USP monograph titration, 0.10 N NaOH |
| Microbial enumeration | TAMC ≤ 100 CFU/mL; TYMC ≤ 10 CFU/mL | Passes test | USP <61> |
| Chloride | 0.0035% max | 0.000015 % | USP <221> |
| Heavy metals | 2.5 ppm max | 0.25 ppm | USP <231> |
| Iron | 0.26 ppm max | 0.025 ppm | HOC 0290 |
| Limit of Diethylene Glycol | 0.05% max | 0.0015 % | GC, flame ionization detector, 0.53-mm x 30-m fused-silica G43 column, 2,2,2-trichloroethanol internal standard |
| Limit of Ethylene Glycol | 0.05% max | 0.001 % | GC, flame ionization detector, 0.53-mm x 30-m fused-silica G43 column, 2,2,2-trichloroethanol internal standard |
| Residue on ignition | 0.0036 wt% max | 0.00025 wt% | Ignition of 50 g, residue moistened with 0.5 mL sulfuric acid and ignited to constant weight |
| Sulfate | 0.0031% max | 0.00025 % | USP <221> |
| arsenic | 0.5 ppm max | 0.01 ppm | — |
| dpg | 0.05 % max | 0.015 % | — |
| pb | 0.51 mg/kg max | 0.005 mg/kg | — |
| meg | 0.0005 % max | 0.00025 % | — |
| po | 0.0005 % max | 0.0001 % | — |
| tpg | 0.015 % max | 0.003 % | — |
| residue | 0.0025 % max | 0.0005 % | — |
| Color, Pt-Co | 10 APHA (maximum) | 2.5 APHA | HOC 0641 |
| Identification A (Infrared Absorption) | Infrared Absorption 〈197F〉 on undried specimen | Passes test | USP <197F> |
| Odor | Pass | Passes test | HOC 0610 |
| Residual solvents | Pass | Passes test | USP <467> |
| Suspended matter | Pass | Passes test | HOC 0171 |
| Composition | 50 % propylene glycol / 50 % deionized water, by volume | Conforms | By formulation; confirmed by specific gravity |
| Freeze point | -28.6 °F (-33.7 °C) max | -28.6 °F (-33.7 °C) | ASTM D1177 |
Specification limits and source-record results are reproduced from the current product reference used by the TDS. This sample is not an issued certificate and does not identify a tested lot. Contact Alliance Chemical with the product and lot number for lot-specific documentation.