Walk into almost any detergent plant, glass furnace, or kraft paper mill in India and you'll find sodium sulphate anhydrous sitting quietly in the raw-material yard — unglamorous, cheap compared to most industrial chemicals, and quietly indispensable. If you're sourcing this compound for the first time, or you're switching suppliers because the last batch didn't hold its purity, this guide walks through what sodium sulphate anhydrous actually is, where it gets used, and how to buy it in bulk without the usual back-and-forth over grade and paperwork.
You can see the current batch and request pricing directly on the Sodium Sulphate Anhydrous – Glauber Salt product page.
What Is Sodium Sulphate Anhydrous?
Sodium sulphate anhydrous is the water-free form of sodium sulphate (Na₂SO₄) — a white, free-flowing crystalline powder with no built-in moisture. It's chemically the same salt found in nature as the mineral thenardite, and it's also recovered as a byproduct from several large-scale chemical processes, including viscose rayon manufacturing and certain acid-neutralisation reactions. Because the anhydrous form has no water of crystallisation, it packs a higher percentage of actual sodium sulphate by weight than its cousin, Glauber's salt.
Anhydrous vs. Glauber's Salt (Decahydrate)
People use "sodium sulphate" and "Glauber's salt" almost interchangeably, but they're not the same product on a spec sheet. Glauber's salt is the decahydrate form (Na₂SO₄·10H₂O) — it carries ten water molecules per formula unit and effectively dilutes the active content to under 45% by weight. The anhydrous grade strips that water out, so buyers get close to 99% Na₂SO₄ in every bag. That difference matters a lot once you're costing out a formulation on a per-kg-active basis.
- Anhydrous form: ~99% Na₂SO₄, low moisture, longer shelf stability
- Decahydrate (Glauber's salt): ~44% active content, prone to caking in humid storage
- Anhydrous is the standard choice for detergent and glass-industry buyers
- Decahydrate still shows up in some cooling and thermal-storage applications
- Always confirm which form a quote is for — pricing per tonne differs sharply between the two
Key Properties and Specifications
Before you commit to a supplier, it helps to know what a normal commercial-grade certificate of analysis should show. Here's a quick reference table.
| Property | Typical Value |
|---|---|
| Chemical formula | Na₂SO₄ |
| Molecular weight | 142.04 g/mol |
| Appearance | White crystalline powder |
| Assay (Na₂SO₄ content) | ≥98–99% |
| Moisture | Low, typically under 1% |
| Solubility | Highly soluble in water, increases with temperature |
| Melting point | ~884°C (anhydrous) |
That said, don't take a spec sheet at face value — ask for the actual batch-wise Certificate of Analysis (CoA), not a generic technical datasheet. A supplier who can hand you both without hesitation is usually the one worth building a repeat order with.
Industrial Uses and Applications
Sodium sulphate anhydrous earns its place in a surprisingly wide spread of industries. None of these uses are exotic — they're all high-volume, everyday manufacturing processes where this salt plays a supporting but essential role.
Detergent Manufacturing
This is the single largest consumer of sodium sulphate anhydrous worldwide, and it's not there just as cheap bulk filler. It's a genuine functional ingredient — it helps control the density and flow of detergent powder, keeps the granules from clumping, and lets formulators dial down the concentration of active surfactants without hurting wash performance.
- Improves powder flow and anti-caking behaviour
- Controls bulk density in spray-dried and agglomerated detergents
- Cost-effective carrier for active ingredients
- Used in both household and industrial-strength detergent formulations
Glass Manufacturing
In glass furnaces, sodium sulphate acts as a fining agent — it helps release trapped air bubbles from molten glass before it's shaped, giving a clearer, more uniform product. Flat glass, container glass, and specialty glass lines all rely on a consistent fining-agent supply, and any variation in purity shows up as visible defects downstream.
Textile Dyeing
Cotton and other natural-fibre dyeing processes use sodium sulphate to help dye molecules distribute evenly across the fabric. It's not the dye itself — it's the salt that pushes the dye out of solution and onto the fibre, which is exactly why textile units are so particular about consistent particle size and low insoluble-matter content.
Paper and Kraft Pulp
Kraft pulp mills use sodium sulphate as a make-up chemical to recover sodium hydroxide and sodium sulphide in the recovery boiler cycle. It's a smaller-volume use than detergents or glass, but it's a steady, recurring one for any mill running a continuous kraft process.
Other and Emerging Uses
Beyond the four big industries above, sodium sulphate turns up in smaller but steady applications — as a filler in certain pharmaceutical formulations, as the food additive E514 in specific, tightly regulated contexts, and even in some thermal energy storage systems that use its phase-change properties. None of these move anywhere near the volume of detergents or glass, but they're worth knowing about if you're scouting new demand.
Storage and Handling
Sodium sulphate anhydrous is hygroscopic enough that poor storage will slowly pull it back toward a hydrated, caked mass — not dangerous, just annoying and wasteful. Keep it in sealed, moisture-proof bags in a dry warehouse, away from direct exposure to humid air, and it'll hold its free-flowing texture for a long stretch of shelf life.
Grades Available and Documentation
BulkFineChem supplies sodium sulphate anhydrous in commercial industrial grade, sold by the kg, MT or truckload depending on your requirement — check current MOQ and packaging options on the product page. Every order ships with a GST tax invoice and a batch-wise Certificate of Analysis from the manufacturer; Technical and Safety Data Sheets (TDS/SDS) are available on request, and large consignments are covered by an e-way bill.
How to Source Sodium Sulphate Anhydrous in Bulk
The process is built around getting you a firm quote fast, rather than making you chase a static price list around.
- Send an enquiry — submit your required quantity and delivery city through the product page or Quick Order form
- Receive a quotation — pricing is shared based on quantity (kg/MT slabs) and your delivery location
- Confirm with advance payment — typically 50–100% advance depending on order size
- Dispatch with documentation — GST invoice and CoA travel with every consignment; TDS/SDS on request
- Pan-India delivery — with e-way billing handled for larger loads
Frequently Asked Questions
Is sodium sulphate anhydrous the same as Glauber's salt?
Not quite. Glauber's salt is the decahydrate form, carrying water of crystallisation and roughly 44% active content. Anhydrous sodium sulphate has that water removed, giving close to 99% Na₂SO₄ by weight.
What's the minimum order quantity for bulk sodium sulphate anhydrous?
MOQ is set per order and depends on packaging (kg bags, MT loads, or bulk quantities) — check the current MOQ on the product page or request a quote for your exact requirement.
Does BulkFineChem provide a Certificate of Analysis with every batch?
Yes. Every shipment comes with a GST tax invoice and a batch-wise CoA from the manufacturer. TDS and SDS documents are shared on request.
Which industries buy sodium sulphate anhydrous in bulk?
Mainly detergent manufacturers, glass producers, textile dyeing units, and kraft paper mills — though smaller volumes also go into pharmaceutical formulations and select food-grade applications.
How is payment structured for bulk orders?
Orders are confirmed against 50–100% advance payment, with the balance, where applicable, settled before or on dispatch depending on order size and terms agreed at the quotation stage.
Can I get a sample before placing a bulk order?
Sample availability is best confirmed directly through a quote request — reach out via the Quick Order page with your requirement.
Is sodium sulphate anhydrous hazardous to handle?
No — it's generally regarded as a low-hazard industrial salt. Standard industrial handling practices, like dry storage and dust control, are enough; it doesn't carry the corrosive or acute-toxicity classifications that some other industrial chemicals do.
The Bottom Line
Sodium sulphate anhydrous isn't a flashy chemical, but it's one of those inputs where a small quality slip — off-spec moisture, inconsistent particle size — creates a big headache several process steps downstream. If you need a supplier that can back every batch with real documentation instead of a generic spec sheet, check current availability and request a quote here, or head to Quick Order to get pricing for your quantity and city.