Developing an Economy, One Shrimp at a Time

Name: Hanoi University of Technology
Country / Territory: Viet Nam
IP right(s): Patents, Trademarks, Utility Models
Date of publication: November 16, 2012

Hanoi University of Technology, Viet Nam

In aquaculture (the branch of agriculture focusing on seafood) in Viet Nam, water impurity is a serious problem that lowers the yield of major food products such as shrimp. Purifying agents are not readily available, especially in many rural areas, and poor water quality adversely affects human and livestock health. To purify water, zeolite (a combination of aluminum, silicon and oxygen) is generally used, as it is effective in purifying both the water and soil in many regions in Viet Nam. Until recently, zeolite has been primarily imported from other countries, and as such has been prohibitively expensive. Many farmers and companies have therefore been unable to adequately purify their water and soil. Producing zeolite domestically in Viet Nam under conventional methods is difficult because of the unavailability of the necessary ingredients and infrastructure.

Water purity is essential for high yield and food safety in aquaculture products such as shrimp (Photo: Flickr/Sergiu Bacioiu)

Research and development

Zeolites were first described in the mid-1700s and were found to have excellent absorption qualities. They have a porous structure that can accommodate many positively charged ions and are hydrated aluminosilicates (minerals containing alumina and silica, the two most abundant minerals in the Earth’s crust) of alkaline and alkaline-earth metals, and naturally form in places such as where volcanic rocks and ash come into contact with alkaline groundwater. As of January 2011, 40 natural zeolites have been identified and over 150 have been synthesized throughout the world. Natural and synthetic zeolites are commonly used commercially because of their unique high absorption rates and decontamination properties, among others. The use of zeolites has promoted the development of many industries, and they are used in a variety of applications from oil refining to wastewater treatment.

The properties of zeolites make them extremely useful for expanding crop and animal production, and they have continued to be a vital tool for agriculture as a whole. For land based agriculture, it increases the efficiency of feed by reducing harmful substances, reduces the risk of intestinal diseases, controls moisture, and keeps down the ammonia content of animal manure. In the case of aquaculture, adding zeolites to the water increases the nutrition efficiency of feed, reduces the threat of diseases, purifies re-circulating hatchery (an aquaculture facility where eggs are hatched under artificial conditions) water, provides oxygen-enriched air for fish breeding and transportation, and reduces the nitrogen content of hatchery runoff waters.

For many of these applications, synthetic zeolites are used due to their high quality, but because of the variety of chemicals required for their production, they are extremely expensive to synthesize. Moreover, the chemicals required for synthesis are not easily accessible. Many developing countries such as Viet Nam therefore do not have access to zeolites, and their agricultural industries suffer. In order to develop a more economically viable solution, in 1998 a team of researchers at Hanoi University of Technology (HUT), funded by the government of Viet Nam and led by Dr. Hoang Trong Yem of the Department of Organic Chemistry, Faculty of Chemical Technologies at HUT, launched a research and development (R&D) program to domestically develop a zeolite material.

Tiny spherical zeolite crystals (Photo: Flickr/BASF)

One of the driving factors behind this project was the shrimp industry in Viet Nam. Shrimp is a vital food commodity for the country, and has overtaken rice as the primary agricultural product in many coastal and central provinces. However, because of high costs many aquaculture farms in Viet Nam use no chemical purifying agents such as zeolite materials. As shrimp grow, many toxic agents are generated and circulated in hatcheries, which lowers the quality of the water and leads to shrimp dying en masse. The remaining living shrimp are then of poor quality and possibly even pose a health risk to consumers. The researchers recognized that using a zeolite material would do a great deal to help solve these problems, and therefore bring an increase in shrimp production and quality in Viet Nam.

Dr. Yem and his team started researching possible ways to develop a zeolite material with locally available minerals. They eventually decided to focus on kaolin, a soft, white clay-like material that is extremely cheap and found in abundant quantities throughout Viet Nam. With millions of tons readily available, Dr. Yem and his team knew that kaolin would be a prime candidate for the project. Their research was focused on three specific types of zeolite: A, P and X. These three types have exceptionally good absorption properties and also have a substantial ion exchange capacity (the degree with which water can absorb and exchange positively charged ions), which makes them particularly suited for aquaculture applications.

HUT’s R&D also focused on building a prototype of the zeolite materials at a pilot scale and then perfecting the production process so it can be produced at the industrial scale, which would allow the domestically developed zeolites to completely replace imported zeolites. Lastly, the research also focused on extending the application of domestically developed zeolites from aquaculture to other forms of agricultural cultivation, such as cattle farms, and oil processing and refining in Viet Nam. After one year of intensive R&D, in September 1999 the team successfully invented a method to transform kaolin into zeolite.


The research team’s efforts resulted in the invention of not one method, but 14 different methods that produce respectively different types of zeolites derived from naturally occurring Vietnamese kaolin. While the fundamentals of each method are the same, they vary slightly to yield the desired type of zeolite. The novelty of the overall method lies in its use of organic kaolin mined in Viet Nam. In addition, all of the zeolite materials can not only be used for increasing the yield and quality of shrimp, but can also be used for raising healthy cattle.

Synthetic zeolites are formed by a slow process of crystallization of a silicon-aluminum gel in the presence of alkalies and organic templates. A unique aspect of the invented methods is that kaolin provides both the silicate and organic properties necessary in only one mineral. This speeds up the crystallization process while at the same time maintaining a high level of quality. The types of zeolite they developed were also painstakingly tailored for use in hatcheries and other aquaculture applications. In addition, because of the abundance of domestic kaolin and the simple nature of the equipment necessary for using it to create zeolite materials, the production method can be easily used in many regions of Viet Nam, regardless of specific geographical characteristics. All of these factors result in an extremely affordable product.

Kaolin is a type of naturally occurring clay in Viet Nam (Photo: Flickr/Tommaso Manasse)

The overarching method is comprised of a number of important stages. First, natural kaolin exhibiting the appropriate properties is identified and collected. The structure, ingredients and quality of the collected kaolin are then analyzed. After this, the kaolin is dried, ground, and calcified (hardened by deposition of or conversion into calcium carbonate or other insoluble calcium compound), which makes it ready for the zeolite crystallization. Once the zeolite crystals have been created, they are added into suitable products (such as fertilizer and shrimp feed, among others) and also to water in hatcheries and soil in agricultural fields.

Researchers at HUT also developed the necessary process that adds their synthetic zeolites into these various commercial products and natural environments. Because their work targeted the shrimp industry in particular, the process is geared toward effectively using the new kaolin-based zeolites in aquaculture applications. However, it also has the potential to be adapted and used in a variety of other agricultural situations.

IP management

In 2005, HUT set up an intellectual property (IP) division under the University’s Science and Technology Office. The IP Division has a multifold mandate, which is: to consult and assist researchers, lecturers and students with securing IP rights (IPRs); to supervise and manage IP; to promote IP activities; to develop and train IP professionals; to supply patent information and IP news to HUT; and to cooperate internationally with other IP entities.

To ensure that these goals are effectively realized, the IP Division follows a specific process for securing IPRs. First, the inventor(s) contacts the IP Division and discloses the invention to them, after which the IP Division evaluates the developed technology. The inventor(s) subsequently complete and submit IP protection applications and any other required documents according to the guidelines of the IP Division. The IP Division then makes any necessary revisions and submits it to the National Office of Intellectual Property of Viet Nam (NOIP). All filing fees are paid by the IP Division on behalf of HUT. In case of any changes or any other action required from NOIP, the IP Division will undertake these in coordination with the inventor(s). When IP protection such as a patent is secured, the IP Division keeps the original certificate and forwards a copy to the inventor(s). All secured IPRs remain the property of HUT.

Patents, utility models, and trademarks

The four trademarks of HUT zeolite products (Photo: HUT)

Following the IP management procedure and guidelines implemented by the IP Division, Dr. Yem and his research team submitted patent applications to NOIP for their invented technologies and processes related to zeolite materials developed from domestically mined kaolin. In all, in 2006 HUT made patent and utility model applications for each of its 14 invented methods relating to domestically developed zeolite.

Four of the applications are for synthesizing different types of zeolite materials, while one application is for synthesizing nano-zeolite materials. Three applications were for a method for producing three different kinds of zeolite from kaolin mined in Viet Nam, while one was for producing a kind of zeolite from general kaolin. Two applications were for the method to produce two different kinds of zeolite from kaolin that has not been subjected to calcination (decomposition, oxidation or loss of moisture through heating), while two more were for producing two kinds of zeolite from domestically mined metakaolin (a form of stronger kaolin). Lastly, one application was for producing a kind of zeolite from Vietnamese metakaolin with specific scientific properties that keep it thermally stable.

In order to successfully market the new zeolite materials, the IP Division registered four trademarks for four different kinds of zeolite: “Bk-z4a,” “Bk-z13x,” “Bk-zsr,” and “Bk-zcr”. Each trademark has the name of the zeolite in Vietnamese and is accompanied by the University’s logo.


HUT has a vast array of existing relationships between its R&D teams and commercial enterprises, and once companies heard of the benefits of the invention, the University was approached with many licensing requests. Moreover, the technology was exhibited at many exhibitions and fairs throughout Viet Nam, and this brought in even more interest from potential licensees. In October 2006, HUT signed an important licensing agreement with a major Vietnamese company (due to confidentiality concerns, “the Company”) for the transfer of the technologies and providing the necessary technical know-how to further commercialization.

In addition to this major licensing agreement, the University also entered into various licensing agreements with companies manufacturing products for raising cattle in the northern province of Bac Giang. Taking the technology even further, HUT signed additional licensing agreements for water treatment in the northern provinces of Ha Tay and Vinh Phuc. Due to the strong network and outreach activities undertaken by the University to promote the technology, HUT has received increasingly more licensing requests from various companies, research institutes and provincial science and technology departments.


The licensing agreement with the Company in 2006 resulted in it building a factory which can produce zeolites of types X and P for aquaculture applications with the capacity of 3,000 tons per year. The factory was built in the Economic Zone of Dinh Vu, in Hai Phong province in northern Viet Nam. All kaolin and other necessary natural materials for use in this factory are taken from the nearby provinces of Hai Dong and Phu Tho, and HUT researchers provide the Company with technological know-how and assistance. Beyond this milestone, by 2011 many other licensees were also undertaking steps to commercialize the technology.

Zeolite products can be used to clean shrimp hatcheries in Viet Nam, such as the one pictured (Photo: Flickr/JvL)

Business results

With the successful commercialization of a production plant in the Economic Zone of Dinh Vu, by 2011 output was valued at seven billion Vietnamese Dong (VND), or approximately US $335,000, annually. Because the demand for zeolite on average steadily increases every year, further commercialization has the potential to bring in even more revenue and also lessen the country’s dependence on expensive imports. In early 2011, HUT’s short term goal is to eventually gain 10% of the market for high quality zeolite materials, which will bring in VND 650 billion (approximately US $31 million). This goal is only taking into account aquaculture applications. If it is expanded to other applications such as raising cattle – another vital agricultural activity - the value will be increased to VND 2.4 trillion (approximately US $115 million) annually.

More than an increase in the yield of aquaculture products and financial results, HUT’s technology has cleaned hatcheries, lakes and rivers, and this has increased the quality of the water for people, animals and the environment. Because of this, the agricultural industry as a whole has benefited, as purified land has increased the volume and health of cattle and other animals raised, and thus the quality of the resulting products.

Simple, pure, and innovative

Reliance on expensive imports can be a heavy burden for an emerging economy such as Viet Nam. With the development of HUT’s unique technology to create zeolite from readily available and abundant kaolin and its strategic use of the IP system and licensing, the agricultural industry in the country is on the cusp of dramatically increasing its self-sufficiency. Unburdened by expensive imports, domestically produced zeolite can ensure healthier livestock, which can help many companies and farmers expand and thus contribute to further development of the economy. Increased access to zeolite can therefore purify hatcheries and fields, sanitize water and increase the economic welfare and health of people throughout the country.