This guide to caustic soda in Oman helps buyers choose between flakes and liquid lye. It also covers how to make up a working solution and how to store and handle it in Omani heat.
If you buy caustic soda in Oman for degreasing, tank or hold cleaning, water treatment or soap making, first choose the form. Solid flakes are typically 98 to 99% sodium hydroxide, and liquid lye is typically 30 to 50%. Flakes suit workshops, ships and sites that buy smaller lots and keep them in a dry store. Lye suits plants with storage tanks and dosing pumps. We supply both from Barka Industrial Area, Sultanate of Oman, on quotation.
What caustic soda is: NaOH, lye and sodium hydroxide
Caustic soda, lye and sodium hydroxide are three names for one chemical: NaOH, CAS 1310-73-2. The name changes with the industry and the region, but the substance is the same. A drum labelled caustic soda lye holds sodium hydroxide dissolved in water. A bag of NaOH flakes holds the solid.
Solid sodium hydroxide is a white, odourless, waxy solid. Its molar mass is about 40 g/mol, its density about 2.13 g/cm3 and its melting point about 318 to 323 °C. It dissolves readily in water, less well in ethanol and methanol, and not at all in ether and other non-polar solvents. A 5% solution has a pH of about 14, and dissolving the solid in water gives off a lot of heat.
Caustic soda flakes vs liquid caustic soda: which grade to buy
Solid caustic soda is sold as flakes, pearls (prills), pellets or granules, typically 98 to 99% NaOH. Liquid caustic soda is a clear, colourless solution, typically 30 to 50%. The common strengths are 32%, 45% and 50%, and 50% is the usual industrial grade. Grades vary by producer, so check the assay on the certificate of analysis for the lot you buy.
Choose the form by job:
- Workshop degreasing, drains and pipe cleaning: flakes. You make up only the strength you need, and a sealed bag keeps well in a dry store.
- Ship hold and cargo tank cleaning: flakes dissolved at the quay or on board, or liquid lye where the crew prefers not to handle the solid.
- Water treatment pH correction and continuous dosing: liquid lye, fed by a dosing pump from a storage tank.
- Soap making and chemical processing: either form. Lye avoids the heat of dissolving, and flakes carry more NaOH per kilogram delivered.
- Food plants and CIP: food processing needs a food-grade product. Tell us the end use when you ask for a quote and we will confirm what we can supply.
To convert between the two: 1 kg of 50% lye contains 0.5 kg of NaOH, so 2 kg of 50% lye does the work of roughly 1 kg of flakes. With lye you also pay to transport the water. With flakes you do the dissolving yourself.
A typical technical-grade flake specification reads NaOH min 98% on a dry basis (typical value around 99.5%), water max about 1% and NaCl max about 100 ppm. These are typical figures for this type of product. Our caustic soda flakes for tank and industrial cleaning are listed as pure and free from other metal impurities.
| Item | Caustic soda flakes | Liquid caustic soda (lye) |
|---|---|---|
| Part number | RXSOL-19-1498-005, RXSOL-19-1498-025, RXSOL-19-1498-050, RXSOL-20-2022-050 | RXSOL-19-1308-020 |
| Typical NaOH content | 98 to 99% (typical for the product class) | 30 to 50% (typical; 32%, 45% and 50% common) |
| Application | Industrial cleaner for oily, greasy, fat and protein-based deposits; tank, hold, drain and pipe cleaning | Intermediate for chemicals; pH control and pump dosing |
| Typical cleaning strength | About 2 to 4% NaOH for heavy grease and oil, about 3 to 4% for tank cleaning (typical) | Same working strengths, made up from lye |
| Packing | Flakes, pellets or granular form; pack size confirmed on quotation | 30 kg liquid pack |
| Technical data | CAS 1310-73-2, HS code 281511, UN1823 Class 8 PG II | CAS 1310-73-2, EINECS 215-185-5, molecular weight 40 |
| MSDS | On request | On request |
Uses in Muscat plants, workshops and ships
Caustic soda is widely used for cleaning. It dissolves oily, greasy, fat and protein-based deposits. With surfactant, rust inhibitors and defoamers added, it works as a strong degreaser. Typical jobs are workshop floors and parts washing in Muscat and Barka, kitchen and drain lines, and hold and cargo tank washing for vessels calling at Sohar, Duqm and Salalah.
Typical caustic cleaning strengths are about 2 to 4% NaOH for heavy grease and oil deposits, and about 3 to 4% for tank cleaning. These are typical figures only, so follow your job procedure. Epoxy tank and hold coatings also have limits for caustic soda. Some coating systems allow about 5% max at 60 °C, so check the coating maker's resistance chart before you raise the strength or the temperature.
Plain caustic soda is enough for fat, grease and protein residues. If the job also needs wetting, rust protection or foam control, a formulated alkaline cleaner works better. You can compare options in our full product range.
Beyond cleaning, sodium hydroxide is used in water treatment for pH control and heavy-metal removal. It is also used in soap and detergent making, textile scouring, petroleum refining, oil and gas processing and biodiesel. Oman makes mainly liquid caustic soda, from chlor-alkali production in Sohar, and liquid has the larger share of the Omani market. Solid flakes are mostly imported or traded.
How to make a working solution from flakes or lye
Always add caustic to water slowly with stirring, never water to caustic. Dilution releases a lot of heat and can cause boiling and spattering. Start with cool water. Mix in a steel, polyethylene or polypropylene container, never an aluminium or galvanised bucket.
These quantities are approximate, measured by weight, and each makes about 100 kg of solution:
- 2% solution: about 2 kg of flakes in about 98 L of water, or about 4 kg of 50% lye in about 96 L of water.
- 5% solution: about 5 kg of flakes in about 95 L of water, or about 10 kg of 50% lye in about 90 L of water.
- 10% solution: about 10 kg of flakes in about 90 L of water, or about 20 kg of 50% lye in about 80 L of water.
If you work with lye rather than flakes, our article on caustic soda lye supply in Oman covers that grade in more detail. The 30 kg liquid caustic soda pack page lists its identifiers.
Storage, safety and first aid in Oman's heat
Keep caustic soda tightly closed in a cool, dry place, away from acids. Flakes are hygroscopic: they absorb moisture and CO2 from the air, and exposed flakes cake within about a year. In a Barka or Sohar summer, keep bags sealed, shaded and on pallets off the floor. Close part-used bags as soon as you have finished with them.
Liquid lye has the opposite problem in cool weather. A 50% solution freezes at around 12 °C (typical) and a 25% solution at around 0 °C. This means 50% lye can crystallise in an air-conditioned store or on cool winter nights inland. Liquid storage tanks should be 316 stainless steel, XLPE or fibreglass, with secondary containment holding 110% of tank volume.
Keep caustic soda away from aluminium, zinc, tin, copper and their alloys, including galvanised metal. Contact with these metals releases flammable hydrogen. Caustic soda is also incompatible with acids, halogens, nitro compounds and strong oxidisers.
Caustic soda is classed Corrosive, GHS Danger, H314 (severe skin burns and eye damage) and H290 (may be corrosive to metals). It causes severe chemical burns and can cause permanent blindness on eye contact. Even dilute solutions below 5% irritate skin, and dust may irritate the respiratory tract. Wear neoprene, nitrile or butyl rubber gloves, chemical splash goggles or a full-face shield, a chemical-resistant apron and closed shoes. Use respiratory protection above 2 mg/m3 airborne.
First aid: flush skin or eyes with water for at least 15 minutes. If swallowed, do not induce vomiting and do not try to neutralise with acids. Get medical help. Ask us for the MSDS, which covers spills and disposal.
Where to buy caustic soda in Oman: Muscat, Sohar, Duqm and Salalah
Muscat Chemical (Muscat & Barka for Business Trading) supplies caustic soda flakes and liquid lye from Barka Industrial Area, Sultanate of Oman. Tell us your delivery site and we will confirm delivery on quotation. Call +968 77333599 or message us on WhatsApp with the grade, quantity and delivery site.
Buyers in the Batinah can also order the same NaOH grade through our Sohar site for Sohar port deliveries. Buyers in Dhofar can use the caustic soda listing on our Salalah site for Salalah port and plant orders. For a written offer with part numbers and pack sizes, use our quote request form.
FAQs: caustic soda in Oman
Is caustic soda the same as lye and sodium hydroxide?
Yes. All three names mean sodium hydroxide, NaOH, CAS 1310-73-2. Lye usually means the liquid solution, and caustic soda flakes means the solid.
Which grade should I buy: flakes, 50% lye or 30% lye?
Buy flakes for workshop degreasing, hold and tank cleaning, and for smaller lots kept in a dry store. Buy liquid lye for pump dosing from a tank. 50% lye carries more NaOH per pack, and a lower-strength lye is less likely to crystallise in cool storage.
How do I dilute caustic soda flakes safely?
Add the flakes slowly to cool water while stirring, never water to the flakes. Use a steel, polyethylene or polypropylene container and wear gloves, goggles or a face shield. About 5 kg of flakes in about 95 L of water makes roughly a 5% solution.
How should caustic soda flakes be stored in Oman's heat and humidity?
Keep the bags tightly closed, shaded, dry and on pallets off the floor, away from acids, aluminium and galvanised metal. Exposed flakes absorb moisture and CO2 and cake within about a year.
Where can I buy caustic soda in Muscat, Sohar or Salalah?
Muscat Chemical supplies flakes and liquid lye from Barka Industrial Area. Tell us your delivery site and call or WhatsApp +968 77333599 for a quote.
To request a quote for caustic soda flakes or lye, message us on WhatsApp at +968 77333599.
Frequently asked questions
Is caustic soda the same as lye and sodium hydroxide?
Yes. All three names mean sodium hydroxide, NaOH, CAS 1310-73-2. Lye usually means the liquid solution, and caustic soda flakes means the solid.
Which grade should I buy: flakes, 50% lye or 30% lye?
Buy flakes for workshop degreasing, hold and tank cleaning, and for smaller lots kept in a dry store. Buy liquid lye for pump dosing from a tank. 50% lye carries more NaOH per pack, and a lower-strength lye is less likely to crystallise in cool storage.
How do I dilute caustic soda flakes safely?
Add the flakes slowly to cool water while stirring, never water to the flakes. Use a steel, polyethylene or polypropylene container and wear gloves, goggles or a face shield. About 5 kg of flakes in about 95 L of water makes roughly a 5% solution.
How should caustic soda flakes be stored in Oman's heat and humidity?
Keep the bags tightly closed, shaded, dry and on pallets off the floor, away from acids, aluminium and galvanised metal. Exposed flakes absorb moisture and CO2 and cake within about a year.
Where can I buy caustic soda in Muscat, Sohar or Salalah?
Muscat Chemical supplies flakes and liquid lye from Barka Industrial Area. Tell us your delivery site and call or WhatsApp +968 77333599 for a quote.