Ecomaterials Research and Development

______http:\\www.paper.edu.cn

Current Opinion in Solid State and Materials Science 7 (2003) 217–223

Ecomaterials research and development activities in China Zuoren Nie *, Tieyong Zuo College of Materials Science and Engineering, Beijing University of Technology, Beijing 100022, PR China Received 30 May 2003; accepted 16 September 2003

Abstract A brief review of the recent advances in the ﬁeld of ecomaterials in China is presented, giving opinions on the current activities and suggesting possible future courses of action. The past 10 years has seen the development of the concept of ecomaterials involving practical research and development of environmentally conscious materials, and the establishment of related systems including national programs and laws. It has been an important period for the development of materials science and the goal of creating a sustainable society in China. It has now become clear that ecomaterials, which exhibit high performance whilst being environmentally benign in their life cycle, are evolving from being only materials for end-of-pipe applications to include all materials being designed on the basis of life-cycle thinking. 2003 Elsevier Ltd. All rights reserved.

Keywords: Ecomaterials; Life cycle assessment; Hazard-free; Green-processing; Higher-eﬃciency; Recyclable

1. Introduction required is sharply increasing, much higher than the world average for GNP basis. This aggravates the re- Materials are one of the basic founding blocks for the source and energy shortage and causes serious envi- development of society and economy. For the produc- ronmental pollution and ecological deterioration. tion, manufacture, application, and disposal of materi- Ecomaterials are not only in demand due to advanced als, numerous energy and resources are consumed, and materials development but also for materials industry by environment deterioration occurs as a result. To har- the global environment, social development, and human monize materials development with environmental existence. protection, sustainable developmental ecomaterials or In recent years, research into ecomaterials has pro- environmentally conscious materials, have been actively gressed in the ﬁelds of metallurgy, metals, non-metals, sought in recent years throughout the world [*1,2,**3]. polymers, wood, and minerals, amongst others. Func- The main activities and schedules related to ecomaterials tional materials for environmental protection, energy- research and development in China are brieﬂy intro- saving materials, materials supporting low-emission duced in this article. systems, and materials designed by means of LCA and In view of the extremely rapid industrial development selected for their lower environmental impact are the in China, there is a great danger that mistakes made in most important areas to concentrate research on when the past by the West may be repeated in China. China is addressing the global environmental problems caused by a large materials producer as well as a user [*4]. The materials technology. Since all countries see environ- principal Chinese raw materials output, including iron mental measures as an important strategy to protect and steel, non-ferrous metals, cement, coal, glass and so their own industry, ecomaterial and ecoproducts devel- on have been largest in the world over recent years. At oped with related technologies have not only become the the same time, the energy and resource consumption popular topics for the basic research, but also one of the most vehement trade strategies in the market competi- tion. Research on ecomaterials has led to the develop-

* ment of new methods for the design of materials which Corresponding author. Tel.: +86-10-6739-1536; fax: +86-10-6739- 2659. have much lower environment loads in their life cy- E-mail address: [email protected] (Z. Nie). cles and can be used to replace other higher impact

1359-0286/$ - see front matter 2003 Elsevier Ltd. All rights reserved. doi:10.1016/j.cossms.2003.09.009 ______中国科技论文在线 http:\\www.paper.edu.cn 218 Z. Nie, T. Zuo / Current Opinion in Solid State and Materials Science 7 (2003) 217–223

materials. Also the ecomaterials learning, to be used as a 2.1. Research on materials life cycle assessment and new concept of materials, still is in the initial stage of the materials flow analysis development, and its science is still in infancy. Moreover additional efforts are still needed for the ecomaterial Life Cycle Assessment (LCA) is a technique for sys- learning, on the publicity and education, and lawmaking tematically analyzing a target from cradle-to-grave, that or evaluation standard etc. is, from resource extraction through manufacture and use to disposal. It is an important constituent of ISO14000 series. It is an effective tool that not only gives 2. Development of ecomaterials concept and evaluation a detailed information of environmental profiles of a method material, product or a process, but also its results are significantly useful for the purpose to improve the uti- Ecomaterials as a new material concept have gained lization efficiency of resource and energy and decrease considerable worldwide attention over decades. It en- environmental impact, as the basis of design for envi- dued materials with the attribute of environmental ronment (DFE). consciousness. In the early stage, only thinking of the Material Life Cycle Assessment (MLCA) is discussed material’s function characteristics to solve environ- and the research is emphasized in China [5–8]. From mental problem was considered. In the last decade 1998, supported by the National High-Tech. R&D (863) ecomaterials activities included the concept’s develop- Program of the Ninth Five-year Plan (1996–2000), the ment, design with ecosystem, and life cycle analysis project Research On Materials Life Cycle Assessment emphasizing all the materials including the construc- was put in practice to develop practical MLCA methods tion material and every kind of functional material primarily with some typical materials and processes, with environmental attribute. For example, how to including steel and iron, aluminum, cement, etc. satisfy a function while lowering the environment load, [**9,*10,11]. From 2001, the follow-up project Materials and how to improve the material’s recycling, or how to Life Cycle Assessment and Its Application has been use minimal amount of material are the key to eco- supported by the 863 Program of Tenth Five-year Plan materials. Environmentally conscious materials are (2001–2005). Focusing on the research of advanced evolving from materials for end-of-pipe application to materials compatible with environment, to accumulate all materials designed by taking into account life cycle the abundant environmental load data about energy thinking over the whole life cycle. Many research act- source, resource and wastes emissions, the measurement vities on ecomaterials bring up new lessons in material of environmental impact (combined with typical mate- science and engineering technique. Ecomaterials learn- rials) is researched [**12]. Based on this data, the data ing involve the production, use, disposal, recovery and model and database framework of MLCA is systemat- each link, and is a multi-disciplinary matter that ically studied. The basic framework mainly includes crosses over material science, environment science, system framework, LCA methodology, energy con- biology, etc., with complicacy of systems engineering. sumption, resource input, and inventory; finally, the Standpoint that developed for more than 10 years is MLCA databases for several typical materials have been widely accepted for materials worker to think as: eco- built in term of this framework [13]. At the same time, materials should be at the same time to have satisfied MLCA software about the data management and LCA usage function with the material of the coordination of evaluation is under development. good environment. According to the relevant research Also a key research project has been supported by report for main characteristics, from material kinds, BNSF on Materials Flow Analysis (MFA) and Data- ecomaterials should be: (1) No poisonous and harm- base in Beijing. It is analyzed by means of MFA that less, including chemical stability, biological safety, utilization efficiencies of natural resources and energy, avoiding green house effect and ozone layer depletion the discharge of waste, and the technical economical effect etc. (2) Lower consumption of energy and re- indices of metallurgical industry, chemical industry, sources over the whole life cycle. (3) Recyclable, reus- building materials industry and petrochemical industry, able and easy recovery. (4) Higher use efficiency with which form the main body of material industry of structural dependability. (5) Reduce pollution to pro- Beijing region [**12]. tect and purify environment, and also include detecting pollutants. For environmentally conscious synthesis and pro- 3. R&D of ecomaterials and related technology cessing (also call the green processing), according to its characteristics, is emphasized on four aspects: energy The research of ecomaterials in China started in the saving, resources saving, zero emission or lower pollu- beginning of the 1990s. Many efforts from universities, tion technology, and technology for environmental de- industries, and national laboratories have been made on contamination. this topic, together with the guidance and support of the ______中国科技论文在线 http:\\www.paper.edu.cn Z. Nie, T. Zuo / Current Opinion in Solid State and Materials Science 7 (2003) 217–223 219

government. The first ecomaterials project financially and Sn–Ag–Cu–Bi alloy have got more utilizable pro- supported by government plan was by the foundation of gress in some projects [15–20]. The melting point is near National Education Committee of China in 1993. Then 200 C, strength >45 MPa, elongation >20%, electricity several projects for basic research and technology de- conductivity >10% IACS, surface tension <470 mN/m. velopment were carried through by NSFC and 863 Oxygen content of the soldering powder of 25–63 lmis program in the Ninth Five-year Plan (1996–2000). In the less than 150 ppm. For the soldering paste leaded, solid National High-Tech. R&D (863) Program of Tenth content of flux <2%, halogens contains <0.3%, expands Five-year Plan (2001–2005), the ecomaterials subject rate >80%, insulated resistance of unwashed surface was set up in new materials field as a special topic to >1.0 · 1011 X. The diameters of BGA soldering ball is progress in ecomaterials with related key techniques to 0.3–0.76 mm with high quantity. Also some projects are meet urgent national needs [*14]. This subject launched developing on Pb-free piezoelectric ceramics, Pb-free several research projects on sustainable developmental crystal and glass, and so on. materials and products. Main studies aspects are to put For nearly 100 years, tungsten added with thorium emphasis on ecofriendly, low cost farmland plastic film (ThO2–W) is still widely applied as cathode materials to with completely degradation potential, ecological large-power transmit and medium heating tubes, TIG building materials, hazardous substance free materials (argon arc welding) electrode, and magnetrons of and clean processing, lower emission and synthetically household-use microwave oven, etc. But thorium is a utilizable new material and technique, sand-fixation and radioactive element whose half life is as long as 10 vegetation materials, and environmental evaluation 1.39 · 10 years. The radioactive pollution of ThO2–W technique for materials and its application. In the Na- during its production, operation and trash is harmful to tional High-Tech Demonstration Program, ecomaterials both human body and environment, to cause cumulative industry has been supported as a special branch. poisoning. A series of rare-earth added tungsten cathode Supported by these projects, progress has been made materials has been developed to replace ThO2–W by in recent years that reformulates and upgrades widely Chinese researcher [21, **22,23–25,*26,*27,28–30]. This used materials as well as ecomaterials. not only avoids the radioactive pollution but also lower the emission operating temperature with better start-up 3.1. No poisonous and harmless materials as well as characteristics, with the emission stability sufficient for processing different applications. Especially in the argon arc welding industrial application case, the arc starting voltage No poisonous and harmless, included chemical haz- and electrode consumption of rare-earth tungsten elec- ardous substance free, longtime stability and biological trode are both lower than that of ThO2–W electrode safety, is the key point for ecomaterials in all kinds of with the same amount added. Also some projects aimed materials. It is not only in the mass consumable struc- at developing Pb-free piezoelectric ceramics, Pb-free ture materials but also in the rapidly developing func- crystal and glass, water-heating electrochemistry syn- tion materials. Such as electronic materials, energy thesize, and so on. materials, biology medicine materials, etc. Electronic functional materials are in great demand in 3.2. Ecocement and ecobuilding materials the information society. With rapid renewal and change of products, waste materials were increased accordingly. Cement made from municipal garbage or factory There are more than 700 kinds of harmful matters in waste as the raw materials and fuel, named as eco- Ôelectronics garbage’. It is more difficult for the function cement, not only lower the consumptions of energy and materials of electronic products to recycle compared to lime-rock mining or other resources in cement produc- structure materials. The environmental problem must be tion, but also reduce the emission to the environment in taken into account at the beginning of design and se- the processing [*31,*32,33]. The wider use of ecocement lection of materials for electronic products. in the municipal construction is a direction which pre- Lead poisoning has been taken cognizance of in the vents and cures pollution while protecting ecology and world bound. Metal lead (Pb) is a very poisonous ele- environment. The industrial research is carrying out in ment in any alloy in which lead cannot be removed Beijing area to meet the needs of the Olympic 2008 in before shredding or re-melting at the end-of-life stage. Beijing. Research and development is mostly focused on The lead-free solder alloy to replace eutectic tin–lead increasing the amount of waste added to the raw ma- solder in electronic product is an urgent demand for terials and removing impurities such as heavy metals in electronic material. Main problems for the lead-free the incinerated ash. More attention is given to eco- solder alloy are on the eutectic point temperature, building materials with environmental function to be strength and elongation, thermal fatigue, surface ten- used inside ecosystem building. It is very active in the sion, electrical conductivity, as well as industrial cost. development of new building materials with environ- Research efforts in lead-free solder added with rare earth mental protection function, recycling of discarded and ______中国科技论文在线 http:\\www.paper.edu.cn 220 Z. Nie, T. Zuo / Current Opinion in Solid State and Materials Science 7 (2003) 217–223

old building materials, manufacturing building materi- support materials, etc. [**41,*42,43]. For instance, mica als from the industry and living wastes, etc. [34–36]. mineral material to replace asbestos, holding-water and Regarding sterilization or self-clean coating, many keep fertilizer mineral material to prevent and cure de- kinds of no poisonous and decontaminating water-sol- sertification, are typical examples. Natural biological uble coating, powder coating, no-solvent coating and so macromolecules are abundant resources. They are not on, have already been developed. Enlarging the surface only abundant raw material sources but also biode- contact angle to water or oil for coating can get the self- gradable ones. There are plenty of wood ceramics and clean function used to the wall of every kind of building. bamboo ceramics made out of natural biological mac- Added with TiO2 of light activity in the coating or on romolecules [*44,45]. By carbonization and heat treat- the glass surface, some decontamination function may ment, the usage efficiency of this kind of natural be attained [37,38]. materials can be increased significantly, realizing higher degree of efficiency in using and recycling of the re- 3.3. Degradable plastics sources.

The white pollutants caused by plastics have already 3.5. Environment engineering materials been identified by all the countries worldwide. Especially in the fields of farmland plastic film and once used Under the guidance of ecomaterial concept, the en- packaging materials, completely degradable plastics are vironment engineering material not only have the de- being screamed for. China is the largest consumer of contamination function but also emphasize itself with farmland film in the world. A variety of researches have coordination of environment. There are many re- resulted in more fruitful aspects including the control of searches on the environment engineering materials that degradable period and function the price compare to allow purification of the environment, prevention of property. One kind of low cost degradable farmland film pollution, and recycling of the waste etc., such as special was made from completely degradable resin consisted of kind of fire retarding or preventing material without use biodegradable polyester PPDO and starch (640 wt%), of asbestos, plastics or bromine free flame retardant added with degradation control agent. The farmland materials, sound-elimination material, smoke and dust film with the controllable degradability can be com- filter material, impact wave absorb material, and so on pletely degraded in a period of time, also with the similar [*46,*47,48,49,*50,*51]. properties of commonly farmland film (the pull burthen For the electromagnetic wave defense material, hu- P1.6 N, the break elongation rate P160%, the bur- man being suffers more and more from electromagnetic then to right angle tear P0.6 N, flow temperature 100– wave. To reduce radioactive contamination, researches 130 C). The average molecular weight of PPDO is concentrate on developing valid shield, especially pro- 30,000–100,000, the melting point is 100–120 C. cessing of shield material [*52,53]. It should shield in the Carbon dioxide plastics, as an advanced technique in electronics equipments as far as possible by different the world with enormous application foreground, not protection layer, to limit the outside radiation of elec- only solves the impact of carbon dioxide on the envi- tromagnetic wave. This is the direction that manages ronment but also lead to complete biodegradation of the from headspring. plastics by returning carbon dioxide into water after incineration of the plastics. The medical use of transparent thin film made from carbon dioxide plastics will 3.6. Clean processing resolve the PVC problem that medical treatment pro- fession has been in puzzle for long time. Adopted rare- Materials clean processing technique, or say zero earths catalyst and noumenon polymerization method, emission and zero waste processing, is, by means of breakthrough progresses have already obtained with synthesizing analysis of every kind of process, to adopt creativity in China [**39,40]. The efficiency of catalyst is validly synthesize technique and consider from the 800 thousands grams polymer per mol metals, the mo- possibility both side of the technique and economic cost, lecular weight is more than 190 thousands. Now the mostly reduce or avoid wastes and pollutants inside the industrial examination products are being produced to material process, or to realize the material processing use for food packaging. technology with decontamination. Biomimetic materials processing offers starting visions of materials processing 3.4. Natural resource ecomaterials for a sustainable future. Such as in the iron and steel metallurgy and machining, directly reducing iron craft Much of the natural minerals have wide application shorten the process and lower the environment burden. foreground on the decontamination, for the treatment The near-last-type machining applied with the short of sewage, replacement of poisonous and harmful ma- process reduces the energy and substance consumption terial, manufacture of the ecobuilding materials, catalyst in the production line. Also a lot of clean production ______中国科技论文在线 http:\\www.paper.edu.cn Z. Nie, T. Zuo / Current Opinion in Solid State and Materials Science 7 (2003) 217–223 221

technology in metallurgy and machining were developed cessing. Combined with ISO 14000 standards, LCA will [*54,*55,*56,*57,*58,59]. be a good method to evaluate the environmental per- In chemical industry, the economic reaction on atom formance of materials, efficiency of resource and energy, level can save consumption to lower the input and less waste emission and so on. The ecofriendly replacement waste output, usually named as Green Chemistry [*60, to poisonous, harmful, expensive, difficult separate ele- *61,62–65,*66]. For example, peroxidation of alkyl ments and the processing of saving energy, lower con- aromatics is the key step for the synthesis of phenols. sumption, zero emission will be the mainstream for Compared with traditional phenol synthesis routes, the ecomaterials development. In which a series of new reaction is featured by low pollution and 100% utiliza- materials with related techniques will be innovated, such tion of reactant atoms, which makes it an ideal green as property control not only by added alloying element synthesis route. but also more by microstructure, as well as the utilizable insensitivity of impurities. And recycling must be taken into account for use and selection of materials. For re- 4. Establishing related organizations to carry out national source protection and synthesis utility, research on the programs and international collaborations replacement and wealth to un-renewable resource may be an important direction. Development of ecomaterials still depends on edu- As a highly speedy developing country, China’s cation and drumbeating aspects. The courses of eco- public opening degree in EMS system is very lower al- materials science and technology have been provided to though EcoLabel Type I and II or III are put into the specialized educational students in some universities. practice. There is no green procurement system. In fact, Master and doctoral students are trained for the sus- it is no real application for LCA and Ecodesign ap- tainable country’s exports. Establishing a completely proach, no standard, no software suitable for China. To ecofriendly educational system, including occupational set up recycling-oriented society is the foremost issues education for grown-ups and extensive education to all facing China on its path to sustainable development in the people, need to be developed along with the formal the new century. It is a new growth opportunity to education. transform the development mode into ecofriendly one. It is equally important to establish related organiza- Formulating and adopting related laws and policies, tions and collaborative research. The ecomaterials developing advanced science and technology, and im- branch of C-MRS was set up. Annual symposiums were proving the public morality may be the key points to- convened. Experts in China enthusiastically joined the wards the ecofriendly development road. In which more international activities which boosts the ecomaterials advanced methods such as EcoDesign, LCA, and MFA research to an in-depth level, greatly enhances the should to be developed by science and technologic re- scholastic status and influence China in this field and search. shortens our distance to the frontier of the international research. Based on the national research project, according to the principle of ISO 14000 series, the first Acknowledgements center for National Materials Life Cycle Assessment in China was established, in cooperation with related The author would like to thank his collaborators, functional department. As a technologic platform for Prof. R. Yamamoto, K. Lee, K. Halada, O. Takai, Z. evaluation and ecomaterials research, the center will Wang, and Dr. X. Di, X. Wu, X. Gong, for their provide services to the government, industry and the valuable contributions. Special thanks go to Dr. public, to progress in the methodology and standard of Mrityunjay Singh, commissioning Editor, for invitation. MLCA and promote standard for corporations, indus- This work is supported by the National High-Tech. try and the nation, also put great efforts on the pro- R&D (863) Program of China. motion of ecomaterials and ecofriendly field in China. Also as an open window to the world, the Center launches international collaborative researches with References JEMAI, APEC, and UNEP. Papers of particular interest, published within the annual period of review, have been highlighted as: 5. Concluding remarks * of special interest; ** of outstanding interest. Development of ecomaterials is the sustainable de- [*1] Yamamoto R. Ecomaterials. Beijing: Chemical Industry Press; velopment direction for materials industry. Higher 1997. ecoefficiency, no poisonous, and zero emission, and [2] Zuo TY, Wang TM, Nie ZR. Ecomaterials research in China. higher recycling are the basis for the ecoproducts pro- Mater Des 2001;22:107–10. ______中国科技论文在线 http:\\www.paper.edu.cn 222 Z. Nie, T. Zuo / Current Opinion in Solid State and Materials Science 7 (2003) 217–223

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