Guo Jie, Cao Bin, Guo Jiuyong, Xu Zhenming
School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
Environ Sci Technol. 2008 Jul 15;42(14):5267-71. doi: 10.1021/es800825u.
Noble metals and Cu mainly are recycled in treating waste printed circuit boards (PCBs), and a large amount of nonmetallic materials in PCBs are disposed of by combustion or landfill, which may cause secondary pollution and resource-wasting. In this study, a kind of nonmetallic plate (NMP) has been produced by nonmetallic materials of pulverized waste PCBs. The NMP is produced by a self-made hot-press former through adding resin paste as a bonding agent. Furthermore, microshapes of nonmetallic materials and effects of the contents and particle sizes of nonmetallic materials on mechanical properties of the NMP are investigated. It has been found that the nonmetallic materials with particle size from 0.3 to 0.15 mm are in the form of fiber bundles, with the majority of fibers being encapsulated in resin. Nonmetallic materials shorter than 0.07 mm consist of single glass fiber and resin powder. When nonmetallic materials content was 20 wt%,the NMP with particle size of nonmetallic materials less than 0.07 mm, has excellent mechanical properties,which results in a flexural strength of 68.8 MPa and a Charpy impact strength of 6.4 kJ/m2. This novel technique offers a possibility for recycling of nonmetallic materials of PCBs and resolving the environmental pollutions during recycling of PCBs.
贵金属和铜主要在处理废印刷电路板(PCBs)时被回收利用,而印刷电路板中的大量非金属材料则通过燃烧或填埋进行处理,这可能会造成二次污染和资源浪费。在本研究中,一种非金属板(NMP)由粉碎后的废印刷电路板中的非金属材料制成。该非金属板是通过自制的热压成型机添加树脂糊作为粘结剂制成的。此外,还研究了非金属材料的微观形状以及非金属材料的含量和粒径对非金属板力学性能的影响。研究发现,粒径在0.3至0.15毫米之间的非金属材料呈纤维束状,大多数纤维被包裹在树脂中。长度小于0.07毫米的非金属材料由单根玻璃纤维和树脂粉末组成。当非金属材料含量为20 wt%时,非金属材料粒径小于0.07毫米的非金属板具有优异的力学性能,其弯曲强度为68.8兆帕,夏比冲击强度为6.4千焦/平方米。这项新技术为印刷电路板非金属材料的回收利用以及解决印刷电路板回收过程中的环境污染问题提供了一种可能性。