Mud plants and rig crews mixing invert emulsion fluids need a dependable fatty acid for the emulsifier package, and we are a stearic acid supplier in Oman based at Barka Industrial Area. In oil based mud, stearic acid reacts with lime to form a calcium soap emulsifier that holds the brine droplets in the oil phase. It also builds viscosity. Lab data show mud emulsified with stearic acid losing stability above about 250°F (121 °C), so for hotter sections you should plan on a packaged HPHT primary emulsifier. Send us your quantity and delivery site and we will quote.
Stearic Acid Supplier in Oman: What We Stock for Drilling Contractors
Our drilling fluids range lists stearic acid under two part numbers: Stearic Acid RXSOL-81-8120-025 and Stearic Acid RXSOL-81-8120-050. Both sit in our drilling fluids and mud chemicals category with the other additives we supply to oilfield contractors. Tell us which part number your mud programme or last purchase order used and we will quote against it.
For mud labs, QA labs and test formulations we also supply Stearic Acid for Synthesis RXSOL-60-6605-612 from our lab chemicals range. Labs in the Sohar industrial area can also find the same grade on our Sohar site.
What Stearic Acid Is: Grades, C16/C18 Content and Typical Specs
Stearic acid, or octadecanoic acid (CAS 57-11-4), is a saturated C18 fatty acid with the formula C18H36O2 and a molecular weight of about 284.5. It is a waxy solid sold as white or almost white flakes, granules, beads or powder with a mild odour. It is practically insoluble in water and soluble in ethanol and light petroleum (hydrocarbon) solvents, which suits it to the oil phase of a mud. Its salts and esters are called stearates.
Commercial stearic acid is a mixture made mainly of stearic (C18) and palmitic (C16) acids. Pharmacopoeia grades are named by C18 content: grade 50 (40 to 60% C18), grade 70 (60 to 80% C18) and grade 95 (more than 90% C18). Industrial flakes are made from tallow or vegetable (palm) feedstock, and the COA or SDS should state which.
Single, double and triple pressed describe how many times the fatty acid cake has been pressed to remove the liquid unsaturated acids. Triple pressed is the most refined of the three and has the lowest iodine value. Your mud programme or emulsifier formulator normally names the grade. Send us that grade and we quote against it.
| Item | Detail |
|---|---|
| Part numbers (drilling fluids) | RXSOL-81-8120-025, RXSOL-81-8120-050 |
| Part number (lab grade) | RXSOL-60-6605-612, Stearic Acid for Synthesis |
| Identity | Octadecanoic acid, C18H36O2, CAS 57-11-4 |
| Application | Fatty acid feedstock for calcium soap emulsifiers in oil based and invert emulsion mud; adds viscosity |
| Acid value (typical) | 206 to 210 for triple pressed tallow flakes; about 194 to 212 across grades |
| Iodine value (typical) | 0.5 max for triple pressed; 4 max for most grades, up to 7 for food grade |
| Titer (typical) | 55 to 56 °C for triple pressed; about 53 to 69 °C across grades |
| Saponification value and unsaponifiable (typical) | 207 to 211; 0.2% max |
| Fatty acid split (typical triple pressed) | About C14 2%, C16 45%, C18 52% |
| Dosage (typical) | About 6 lb/bbl primary emulsifier in one 70/30 lab formulation; confirm by pilot test |
| Packing | Class commonly in 25 kg or 50 kg bags, palletised; pack size confirmed on your quote |
| HS code | 3823 |
Spec figures are typical values for this product class taken from published datasheets. They are not the measured spec of a particular lot, so check the COA for each lot you receive.
How Stearic Acid Works in Oil Based Mud
An oil based or invert emulsion mud carries brine droplets inside a continuous oil phase. Emulsifiers reduce the interfacial tension between oil and water so that a stable emulsion forms. Fatty acids are the raw materials for many drilling fluid additives, including emulsifiers, oil wetting agents and lubricants. Most commercial emulsifiers are based on tall oil fatty acid, whose main fatty acids are stearic and palmitic.
When you add stearic acid and lime to the mud, the acid reacts with the lime (Ca(OH)2) to form a calcium fatty acid soap. The soap film surrounds each brine droplet, and its fatty chain extends into the oil phase. This calcium soap emulsifier is what keeps the brine dispersed while the mud circulates and sits static.
Stearic acid also thickens the mud. In a lab test of 80/20 oil-water invert emulsion mud at 250°F, mud with stearic acid as the primary emulsifier gave higher plastic viscosity (15 cP), yield point (7 lb/100 ft²) and gel strength than a commercial emulsifier. Allow for that extra viscosity when you set your organoclay and base oil additions.
Temperature limit and HPHT wells
The same study found that stearic acid emulsified mud became unstable above about 250°F (121 °C) because the stearic acid broke down thermally. Check the expected bottom hole temperature before you choose the emulsifier. For HPHT wells, packaged emulsifiers with more complex structures are better suited, and your mud engineer should specify one for those sections.
Lime, CaCl2 Brine and Typical Usage per Barrel
Lime goes in with stearic acid because the calcium soap forms only when calcium hydroxide is present. One typical lab formulation, tested in the API RP 13B-2 style in a 350 mL lab barrel at 70/30 oil-water ratio, used about 152.8 g base oil, 6.0 g primary emulsifier, 4.0 g secondary emulsifier, 10.0 g lime, CaCl2 brine made from 80.8 g water and 28.9 g CaCl2, and barite for weight.
One gram in a 350 mL lab barrel equals one pound per barrel in the field, so that works out at roughly 6 lb/bbl primary emulsifier. Treat this as a typical value for one formulation and not a fixed dosage. Run a pilot test in your mud lab with your own base oil, brine and organoclay, check rheology and emulsion stability after hot rolling, then scale up.
Packing, Storage in Oman's Heat and Safety
Stearic acid of this class commonly comes in 25 kg or 50 kg bags, HDPE laminated or kraft with a liner, and also in drums, palletised and shrink-wrapped. We confirm the pack size for each part number on your quote.
Store the bags in a cool, dry, ventilated area away from heat sources and direct sunlight, in tightly closed original containers. A storage range of about 2 to 40 °C is typical. Summer heat in containers and open yards at Duqm, Fahud or Nizwa can soften or cake the flakes, so keep stock shaded, use the oldest bags first and plan on a typical shelf life of about 1 year from manufacture for unopened bags.
Stearic acid is generally not classified as hazardous under GHS/CLP and may cause mild skin or eye irritation. Typical oral LD50 (rat) is greater than 2,000 mg/kg, and it is not regulated for transport under ADR, IMDG or IATA. At the mud plant or rig, minimise dust and avoid breathing dust. Dust deposits can make floors slippery. Use gloves, safety goggles where dust is possible, and a particulate respirator if dust is present.
Keep it away from strong oxidising and reducing agents and from strong acids and bases, and avoid heat, humidity and dust generation. Combustion gives CO and CO2. Extinguish with water spray, foam, dry chemical or CO2.
For your QA and customs file, ask for the COA per lot showing acid value, iodine value, titer and C16/C18 split, along with the SDS, the HS code (3823), country of origin and whether the feedstock is vegetable (palm) or tallow.
Where to Buy Stearic Acid in Muscat and Oman
Oman Chem (Muscat & Barka for Business Trading) is a stearic acid supplier in Muscat and Barka, based at Barka Industrial Area, Sultanate of Oman. Call +968 77333599, message us on WhatsApp at +968 77333599 or email muscatchem@gmail.com with the part number, quantity and delivery site.
Tell us your delivery site and quantity and we will confirm availability and delivery terms on your quote.
FAQs: Stearic Acid for Drilling Fluids in Oman
Who supplies stearic acid in Oman and can deliver to Muscat, Duqm or Nizwa?
We do. Oman Chem lists stearic acid under part numbers RXSOL-81-8120-025 and RXSOL-81-8120-050. Send us your quantity and delivery site, whether Muscat, Duqm, Nizwa or elsewhere, and we will confirm availability and delivery on your quote.
Can stearic acid be used as an emulsifier in oil based mud?
Yes. It reacts with lime to form a calcium fatty acid soap, which surrounds the brine droplets and keeps the invert emulsion stable. It also raises plastic viscosity, yield point and gel strength.
What is the maximum temperature for a stearic acid based mud emulsifier?
Lab data show stearic acid emulsified mud becoming unstable above about 250°F (121 °C) as the acid breaks down thermally. For HPHT wells, use a packaged emulsifier with a more complex structure.
How much emulsifier is used per barrel of oil based mud?
One typical 70/30 lab formulation used 6.0 g primary emulsifier per 350 mL lab barrel, roughly 6 lb/bbl. This is a typical value, so confirm your own dosage by pilot testing.
Is stearic acid hazardous, and is it regulated for transport?
It is generally not classified as hazardous under GHS/CLP, may cause mild skin or eye irritation, and is not regulated for transport under ADR, IMDG or IATA. Control dust and wear gloves and goggles when handling.
To order, send your part number and quantity through our quote request page or on WhatsApp at +968 77333599, and we will reply with a quote.
Frequently asked questions
Who supplies stearic acid in Oman and can deliver to Muscat, Duqm or Nizwa?
We do. Oman Chem lists stearic acid under part numbers RXSOL-81-8120-025 and RXSOL-81-8120-050. Send us your quantity and delivery site, whether Muscat, Duqm, Nizwa or elsewhere, and we will confirm availability and delivery on your quote.
Can stearic acid be used as an emulsifier in oil based mud?
Yes. It reacts with lime to form a calcium fatty acid soap, which surrounds the brine droplets and keeps the invert emulsion stable. It also raises plastic viscosity, yield point and gel strength.
What is the maximum temperature for a stearic acid based mud emulsifier?
Lab data show stearic acid emulsified mud becoming unstable above about 250°F (121 °C) as the acid breaks down thermally. For HPHT wells, use a packaged emulsifier with a more complex structure.
How much emulsifier is used per barrel of oil based mud?
One typical 70/30 lab formulation used 6.0 g primary emulsifier per 350 mL lab barrel, roughly 6 lb/bbl. This is a typical value, so confirm your own dosage by pilot testing.
Is stearic acid hazardous, and is it regulated for transport?
It is generally not classified as hazardous under GHS/CLP, may cause mild skin or eye irritation, and is not regulated for transport under ADR, IMDG or IATA. Control dust and wear gloves and goggles when handling.
