A group of scientists in Vietnam recently conducted research to use carnadol, a natural phenol obtained from cashew nut shell oil, to prevent metallic materials from corrosion. The recent discovery makes cashew nut shells, long regarded as waste by many people, as the new ‘liquid gold’ from Vietnam, creating market worth hundreds of millions dollars a year.
Vietnam has exported cashew nut shell oil since 1999. Today, Vietnamese enterprises export 600,000 tons of the oil to China, South Korea, Indonesia and Spain with export value worth $7 million a year with the profitability rate of 20%, as quoted by The Voice of Vietnam.
In the past, China was the biggest consumer, but it has been replaced by South Korea. Do Nguyen Kien, director of F.T.E Technology Development, believes that Vietnam’s cashew nut shell oil from Vietnam can even meet standards for the US market.
Vietnam has great advantages to become a world’s cashew nut shell oil production base. "Though cashew nut shells are a by-product, it is the major source of income of the company," said Kien to Vietnam Net Bridge.
The cashew nut shell oil is widely used in industries as material to make adhesives, anti-corrosive metal, insulating materials, electronic products boards, forest product preservatives, and structural wood treatment liquid. It can also be used in the electrical and electronic industries.
Today, with proper treatment, Vietnam could earn bigger money if they developed more valuable products from cashew nut shell oil, such as Carnadol, making Carnadol the next promising export commodity from Vietnam.
In countries with hot weather and high humidity, the demand for substances which can protect construction works, machines and equipment from corrosion is especially high. Carnadol is a good solution.
The scientists from the Youth Scientific and Technological Promotion Center (TST) headed by Pham Quoc Nghiep used the cardanol extraction method from cashew nut shell with supercritical CO2 technology. The carnadol content obtained was 23% with a purity of 68.6%. The product can protect metal at a high rate of 84%.
It is estimated that one ton of dried cashew can produce 700-750 kilos of shells from which 154 kilos of cashew nut shell oil is created.