Tung Oil

Plant

Tung oil is a remarkable natural product. It is derived from the seeds of the Tung tree. This oil is highly valued for its unique drying properties. It has extensive applications, especially in industrial uses.

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What is Tung Oil?

Tung oil is widely recognized. It is also commercially known as Vernicia Montana Oil. Another common name is China Wood Oil. The scientific name for the Tung tree is Aleurites montana. It also has other names like “oil paint tree” or “tung-tree.” This tree belongs to the Euphorbiaceae family. Tung oil is obtained through pressing the seeds. Vietnam is a significant origin for this oil. It boasts an annual supply capacity of 300 tons.

Description and Habitat

The Tung tree (Aleurites montana) is a large tree. It can grow up to 8 meters or more in height. Its trunk is smooth. Leaves are diverse in shape. They can be deeply lobed or shallowly cut. Some are entire and heart-shaped. The upper surface is glossy and dark. The underside is dull and lighter in color. All leaf variations share a common feature. Two distinct red glands appear at the base of the leaf blade. They are also found in the lobe axils. Leaf stalks are long, typically 7-10cm.

Flower

Flowers are unisexual. They are often monoecious, occasionally dioecious. The corolla has 5 petals. They are white with purple spots at the base. Fruits are egg-shaped and green. They measure 3-5cm in diameter. Their outer surface is wrinkled. Each fruit is structured from three shell segments. Each segment has a raised vein. Three seeds inside contain oil-rich endosperm.

The main flowering season is April. Flowers often appear before young leaves. A second flowering period can occur in September. Fruits from the first flowering ripen around October.

Cultivation

Tung trees grow wild and are widely cultivated. They thrive across Vietnam, from highlands to lowlands. They grow in mountainous areas and plains alike. Tung prefers cool, well-drained soil. It also grows well on slopes. Most Vietnamese provinces have Tung trees. In the North, these include Ninh Binh and Nam Dinh. Hoa Binh, Ha Tay, and Phu Tho are also common areas. In the Central region, Thanh Hoa and Nghe An have them. Tung also grows and is cultivated in South China. These provinces include Guangdong and Guangxi.

While Tung is not very demanding, it thrives in suitable soil. Well-drained, cool, and rich soil promotes rapid growth. Trees flower as early as their second or third year. Branches grow in even, horizontal tiers. Tung trees can provide shade for tea, pineapple, or coffee plantations. One quintal (100 kg) of unshelled seeds yields about 19-20kg of oil. It also produces 60-65kg of oil cake (residue).

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Quality Standards and Chemical Composition of Tung Oil

Tung oil possesses specific quality characteristics. These contribute to its unique properties.

Physical and Chemical Indicators

Tung oil is a yellow liquid. It has a distinctive aroma. Its specific gravity at 20°C is 0.920-0.945. The refractive index at 20°C is 1.500-1.520. The acid value is typically 1.4. The iodine value ranges from 149.5-170.58. The saponification value is between 193.38-196.73. These metrics define its quality.

Main Component: Alpha-Eleostearic Acid

The primary component of Tung oil is alpha-eleostearic acid. It makes up 70-80% of its fatty acid content. This is an unsaturated fatty acid. It has three double bonds. This structure gives it strong oxidizing capabilities. Therefore, the oil dries quickly. When dry, it forms a film. This film is highly moisture-resistant. It can withstand significant weather changes. It also has good elasticity. These qualities provide anti-rust effects.

After oil extraction, the remaining oil cake is valuable. It contains up to 50% crude protein. It also has 7.5% ash and 3% cellulose. Other compounds are present, including saponin. However, the leaves and seeds of the Tung tree contain toxic saponins. Therefore, they cannot be used as animal feed.

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Diverse Applications and Benefits of Tung Oil

Tung oil offers important properties. Many other oils do not possess these. It is resistant to high temperatures, water, and salt.

Industrial Applications of Tung Oil

Because of its unique properties, Tung oil is a valuable raw material. It is used in heat-resistant paints. It is also vital for decorative paints. Acid-resistant paints benefit from it. Paints used in highly corrosive environments employ it. Even defense-related paints utilize its qualities. Due to these special characteristics, Tung oil is a very valuable product.

In industry, Tung oil makes high-grade paints. These include paints for cars, airplanes, and ships. It is also used in electrical insulating paints. It contributes to heat-insulating paints. It finds use in plastics and synthetic rubber. Tung oil is used in soap and artificial leather. It is found in oilcloth and linoleum. It is also used in fine art paints and printing inks. The oil cake (meal) can be used as fertilizer. It can also be animal feed after detoxifying the harmful compounds.

Other Uses of Tung Tree Parts

The fruit husks can be processed. They are used to make activated carbon. Tung wood is white and soft. It is susceptible to termites. Therefore, it can be used for pulp. It also serves as firewood. Recent research from the University of Forestry suggests more uses. Tung wood can be treated. It can then produce engineered wood panels.

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Storage and Precautions for Tung Oil

Proper handling and storage are crucial for preserving Tung oil.

Safety Guidelines

Always read instructions before use. Discontinue use if a strange odor or color is detected. This may indicate spoilage or contamination.

Storage Conditions and Shelf Life

Store Tung oil in a tightly sealed container. Keep it in a dry place. Avoid direct sunlight. Also, keep it away from open flames. This helps maintain its quality. Tung oil typically has a shelf life of 3 years from its manufacturing date.

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Packaging

Packaging: Tung oil is packaged in units of Liters or Kg according to customer requirements: 5L, 10L, 30L, 180L / 5Kg, 10Kg, 30Kg, 180Kg…

Storage: The product is contained in standard HDPE packaging. Store in a cool, dry place away from direct sunlight. Avoid contact with eyes, open wounds, and sensitive skin areas.

Transportation: Domestic: Flexible nationwide transportation by ship, truck, or airplane…

Export: By ship/airplane, Export conditions: FOB/CIF/..