This comparison is vital for the Textile and Dyeing industries, as it highlights the difference between a water-insoluble oil and a water-soluble surfactant.
Executive Summary
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Raw Castor Oil: The natural triglyceride extracted from the seed. It is hydrophobic (repels water) and used as a lubricant or chemical feedstock.
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Turkey Red Oil (TRO): Produced by reacting castor oil with sulfuric acid (sulfonation). It is the first synthetic detergent and is completely water-soluble.
Technical Specification Table
| Parameter | Raw Castor Oil | Turkey Red Oil (TRO) |
| Nature | Hydrophobic (Oil) | Hydrophilic (Water-Soluble) |
| pH Value | Neutral (6.5 – 7.0) | Acidic to Neutral (7.0 – 8.5) |
| Active Matter | 100% | 30% to 70% (Customizable) |
| Solubility | Soluble in alcohol/solvent | Instantly soluble in water |
| Appearance | Viscous, Pale Yellow | Transparent, Deep Amber/Red |
Key Differentiators: A to Z
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Water Solubility: Raw oil floats on water. TRO disperses instantly, making it perfect for water-based dye baths.
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Emulsification: TRO acts as an emulsifier for other oils. Raw oil requires an external emulsifier to mix with water.
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Industry Use: Raw oil is used for machinery; TRO is used in textile dyeing, leather tanning, and agriculture (as a surfactant).
2. Dehydrated Castor Oil (DCO) vs. Raw Castor Oil
This comparison is critical for the Paint, Varnish, and Coating industries.
Executive Summary
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Raw Castor Oil: A “non-drying” oil. It stays wet/oily when exposed to air.
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Dehydrated Castor Oil (DCO): Produced by removing the hydroxyl group ($OH$) from the ricinoleic acid chain. This creates a “drying” or “semi-drying” oil that hardens when exposed to air.
Technical Specification Table
| Parameter | Raw Castor Oil | Dehydrated Castor Oil (DCO) |
| Drying Property | Non-Drying | Drying / Semi-Drying |
| Viscosity (@ 25°C) | 6 – 9 Poise | 1.5 – 2.5 Poise (Lower) |
| Iodine Value | 82 – 90 | 125 – 140 (Higher) |
| Hydroxyl Value | 160 – 168 | Max 10 (Almost removed) |
| Color | Pale Yellow | Pale Yellow to Clear |
Key Differentiators: A to Z
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The Drying Process: DCO contains “conjugated double bonds.” When painted onto a surface, it reacts with oxygen to form a hard, flexible, and non-yellowing film. Raw oil will never dry and will remain sticky.
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Yellowing Resistance: DCO is famous for its “non-yellowing” property. Unlike linseed oil, DCO-based paints stay white over time.
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Primary Use: DCO is used in High-end Enamels, Alkyd Resins, and Varnishes. Raw oil is used as a plasticizer.
3. Heptaldehyde vs. Undecylenic Acid
These are the two “twin” products of the Pyrolysis (Cracking) of castor oil. When you heat castor oil to high temperatures, it splits into these two chemicals.
Executive Summary
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Undecylenic Acid: The C11 portion of the cracked molecule. A solid/liquid acid used for polymers and pharma.
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Heptaldehyde (Heptanal): The C7 portion of the cracked molecule. A highly volatile, liquid aldehyde used for fragrances and rubber.
Technical Specification Table
| Parameter | Undecylenic Acid | Heptaldehyde |
| Chemical Formula | $C_{11}H_{20}O_2$ | $C_7H_{14}O$ |
| Molecular Weight | 184.28 g/mol | 114.18 g/mol |
| Boiling Point | 275°C | 153°C (Highly Volatile) |
| Odor | Pungent, Sweaty | Strong, Fruity, Fatty-Green |
| Functionality | Acid ($COOH$) | Aldehyde ($CHO$) |
Key Differentiators: A to Z
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Carbon Chain Length: Undecylenic is a C11 acid (longer). Heptaldehyde is a C7 aldehyde (shorter).
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Volatility: Heptaldehyde evaporates very quickly and is highly flammable. Undecylenic acid is much more stable.
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Fragrance Industry: Heptaldehyde is a key building block for fragrances (like Jasmine and Violet) and flavors. Undecylenic acid is for medicinal and plastic use.
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Rubber Chemicals: Heptaldehyde is used to produce accelerators for rubber vulcanization.
