Caustic Soda Lye
CAS 1310-73-2
| Product name | Caustic Soda Lye |
|---|---|
| Synonyms | sodium hydroxide lye, NaOH lye, lye 48%, liquid caustic |
| C.A.S. number | 1310-73-2 |
| Molecular formula | NaOH (aqueous solution) |
| Molecular weight | 40.00 g/mol (NaOH solute; not the molar mass of the 48% solution) |
| Grade supplied against | 48% membrane grade |
| Appearance | Clear, colourless, odourless liquid; commercial lye may appear slightly turbid or off-white |
| Product group | Alkalis & Bases |
| HSN code | 2815 12 00 |
| Country of origin | As stated on the producer’s documents for the lot supplied; confirmed at offer stage |
| Packing | Road tanker · 250 kg drum |
| Storage | Store above the crystallisation point (Olin specifies above 16 C / 61 F) in closed, vented tanks of carbon steel, 304/316L stainless steel, or lined steel/HDPE/FRP rated for 50% caustic. Never store or handle in aluminium, zinc, tin, galvanised or brass equipment. Keep in a bunded, caustic-resistant, well-ventilated area segregated from all acids and from food and feedstuffs. Keep containers tightly closed to prevent CO2 absorption and dilution. Provide an eyewash station and safety shower at the point of use. Always add caustic soda solution to water with constant agitation — never add water to the caustic. |
| S. No. | Test parameter | Specification | Method |
|---|---|---|---|
| 1 | Description | Clear, colourless, odourless liquid; commercial lye may appear slightly turbid or off-white | Visual |
| 2 | Identification | Conforms to the substance supplied | Instrumental or chemical test, per method agreed |
| 3 | Assay / grade | 48% membrane grade | Titrimetry or instrumental, per method agreed |
| 4 | Physical state | Liquid (aqueous solution, 48% w/w NaOH) | Visual |
| 5 | Solubility in water | Completely miscible with water in all proportions; dilution is strongly exothermic | Per the test method agreed |
| 6 | pH | 14 (as supplied, undiluted — Olin SDS); 14 at 0.5% dilution (Braskem SDS). A 1% NaOH solution is approximately pH 13 | Potentiometry |
| 7 | Relative density | 1.4-1.6 at 25 C for 45-50% lye (Aditya Birla SDS); relative density 1.353-1.528 at 20 C across the 30-54% range (Olin SDS) | Densitometry / hydrometry |
| 8 | Melting / freezing point | Crystallisation point approx. 12 C for 45-50% lye (Aditya Birla SDS). Exact value is strength-dependent; a precise figure for 48.0% is Not available — confirm against producer data | Capillary / thermal |
| 9 | Boiling point | Approx. 140 C (45-50% lye; Aditya Birla and Braskem SDS). Olin states it varies with concentration | Distillation range |
| 10 | Flash point | Not flammable (no flash point). Caution: contact with aluminium, zinc, tin or galvanised steel liberates flammable hydrogen gas | Not applicable — the substance is not combustible |
| 11 | Additional parameters | To the specification agreed before order | As agreed |
UN 1824 · Class 8 (Corrosive) · Packing group II
Proper shipping name: SODIUM HYDROXIDE SOLUTION
Need this on your own enquiry, or need the producer’s batch certificate of analysis for a consignment? Email the sales desk or see what travels with the load.