HBCD to Be Listed as a POP

By Gong Yanling, China National Chemical Information Center

According to information released from the "Stockholm Convention on the review progress of hexabromocyclododecane (HBCD) as well as Voluntary Emissions Control Action Program (VECAP)" seminar recently held by China Flame Retardant Society, flame retardant HBCD will possibly be put in the list of POPs (persistent organic pollutants) of Stockholm Convention (hereinafter referred to as "the Convention") in the next year.
   Ding Qiong, Director of the National Stockholm Convention Implementation Coordination Group Office, Foreign Economic Cooperation Office of the Ministry of Environmental Protection, introduced "the Convention" on the review progress of HBCD. At present, HBCD has passed the three-stage review of "the Convention" on the product characteristics, risk assessment, the influence of substitution and elimination. HBCD has been basically identified to possess the properties of POPs and meets the requirement of "the Convention" for such restricted products. It is expected that the proposal will be submitted for approval in the next year. Barring an unforeseen turn of events, HBCD will be officially included in the controlled list of POPs products in the next year. Liu Jianguo, Associate Professor of Peking University further explained that HBCD may be included in banned or exemption use in "the Convention" annex a, and the control will take effect as early as possible in 2014. After "the Convention" takes effect, some countries will automatically control the restricted products. China will institute the corresponding control after government approval and will usually give the sectors and enterprises a year or two delay. At that time, the measures that may be taken include the reduction or elimination of the production and application of HBCD products, the control of their waste emissions and the active promotion of substitutes for the products.

Alternatives to HBCD are hard to find, in its principal applications

As an alicyclic additive type flame retardant with high bromine content, HBCD has the characteristics such as low dosage, good flame retardant effect and little influence on the physical properties of the materials, etc. HBCD is mainly used for thermoplastic and thermosetting polymer materials, and is especially suitable for expandable polystyrene (EPS) (the reference consumption is 2%) and polypropylene (the reference consumption is 2% HBCD and 1% antimony trioxide) and other styrene resins. At present, the world’s output of HBCD is around 25 thousand tons per year, and the European Union, the United States and China are the largest producers and consumers. China has more than a dozen HBCD production enterprises with the national output ranking the first in the world. China's output of HBCD reached around 18 thousand tons in 2011 and the amount exported was around 5 000 tons. Major export destinations include Europe, Japan and Korea, etc. After 2000, the consumption of HBCD in China began to grow significantly. Especially, the consumption of HBCD for flame retardant EPS and extruded polystyrene (XPS) plates is relatively big. At present, around 9 000 tons of HBCD is used for the production of EPS, and 3 000 tons of HBCD is used in XPS production each year.
   EPS flame retardant plate is the largest application field of HBDC and widely used in the external wall thermal insulation of buildings. If HBDC is included in the list of POPs and its application is gradually banned in China, the downstream application fields will be severely affected. There is already much discussion of R&D for substitutes that can meet the present industrialization and large-scale requirements.
   Hou Shuting, Chairman of the EPS Professional Committee of China Plastics Processing Industry Association, told CCR that with the present methods and technical level, no suitable substitute could be industrialized to replace HBCD in the application of polystyrene plates. The restriction of HBCD will greatly affect the production and utilization of China's energy-saving building thermal insulation material EPS. Moreover, the development of flame-retardants has a long cycle of development and technology maturity, so HBCD substitutes need time for promotion and utilization. And overall effect of such a substitute throughout its whole product life cycle may not be able to meet the requirements of safety, energy conservation and environmental protection. The same concerns are expressed throughout the sector. "If HBCD is to be restricted, we hope that the government will give enough delay time, offer policy support, capital and other aspects, and help the sector to develop the substitutes with environmental protection as soon as possible," an expert from a related enterprise expressed.

R&D for HBCD substitutes is under way

Qian Lijun, Professor from Beijing Technology And Business University, showed the progress of HBCD substitutive technology in the seminar. "At present, the EPS sector’s consumption of HBCD is the largest, and the replacement of HBCD there is the most difficult," he expressed. As HBCD has been recognized for some time as a persistent toxic pollutant, research and development of substitutes has been in progress. In the present research, there are preliminary promising results on three alternatives to HBCD for EPS production. One is expandable graphite. The dispersed granules of the expandable graphite can have better flame retardant effect, the resulting flame retardant EPS has good performance index and an earlier problem of managing the graphite’s dispersion has been basically solved. Brominated polybutadiene is the second candidate. It has the same bromine content as HBCD and a similar molecular chain structure. At present, the scaling-up of brominated polybutadiene production has been started. One problem is that the plates crack easily; however, this has basically been solved by fine treatment. In addition, other products including Emerald Innovation 3000 of Chemtura can also be used as substitutes for HBCD.
   In addition, the replacement scheme of directly replacing EPS and using new thermal insulation materials such as polyurethane, expanded perlite, phenolic resin and rock wool can also be considered. Along with the gradual advance of the national program to conserve energy in buildings, the selection of more thermal insulation materials will be imperative.

VECAP highlights the responsibility of the enterprises

In the seminar, professor Zhou Zhengmao, Secretary-General of the China Flame Retardant Society, appealed to the domestic production and application enterprises of HBCD and flame-retardants to actively implement VECAP. It is reported that VECAP is an organization that was jointly established by the international brominated flame retardant manufacturers and downstream users in 2004. VECAP takes the initiative to minimize the emissions of the brominated flame-retardants to the environment through continuous technical progress. "Code of Good Practice" being planned for release by VECAP effectively helps enterprises to take measures to reduce the flame retardant emissions. At present, the content of VECAP has extended to various flame-retardants and chemicals such as pentabromophenyl ether, HBCD and tetrabromobisphenol A (TBBPA), and has been implemented in Europe, North America and Asia-Pacific region. “Since 2008, some VECAP activities have been spread in the Asia-Pacific region such as in China, Korea and Japan," said Ms. Danielle Goossens, Leader of the Product Management Group of the European Flame Retardant Association. “If China's brominated flame retardant plants and the user bases are capable of performing the best available technology of VECAP, emissions will be reduced effectively,” she expressed.