Collaborative Research: Understanding and Optimizing A Supercritical Fluid Process for Recycling of Printed Circuit Boards

1133984(张)。电子设备的广泛使用和产品生命周期的缩短使处理日益增多的过时电子设备成为一项具有挑战性的任务。每年产生的大量电子废物（电子废物）以及缺乏能够处理日益增加的电子废物量的既定方法构成了严重的环境威胁。在成功回收电子设备的挑战中，印刷电路板（PCB，每一种电子产品的主要部件）的回收被认为是最困难的问题之一，因为PCB的复杂结构和复杂的材料组成。目前的PCB回收行业采用传统的冶金技术，将纤维增强聚合物基体材料焚烧。虽然传统的冶金技术已经为提高报废电子产品的回收效率做出了很大的努力，但PCB回收行业仍然面临着环保性能差和经济效益有限的问题。最近，在EAGER的资助下，该奖项的pi展示了在相对低/中温度和压力下开发新型超临界流体（SCF） co2基PCB回收工艺的概念验证初步工作。探索性实验表明，多氯联苯与金属分层，玻璃纤维保持其原始形态，这不仅可以提高贵金属的回收率，还可以提高非金属材料的回收率。该工艺为PCB的回收利用开辟了一个新的维度，并提供了满足经济和环境要求的可能性。在当前项目中，课题组将系统研究超临界流体过程下pcb中键合材料的脱层机理，寻求理解结构/工艺关系。虽然文献记载了超临界流体在聚合物合成和加工中的应用，但现有的揭示超临界流体中聚合物材料性能的工作有限。此外，课题组将在机理研究的基础上，通过实施工艺条件对SCF工艺进行优化，并对工艺性能进行系统评价。最后，团队将在成本、能源和环境影响方面对回收过程进行建模和验证。该团队将与工业合作伙伴合作，促进基础研究向实际应用的转化。此外，研究和教育将在整个项目期间进行整合。

1133984 (Zhang). Widespread use of electronic equipment and shortening of product life cycles have created the challenging task of dealing with the ever-increasing quantity of obsolete electronic equipment. The huge amount of electronic waste (E-waste) generated each year and the lack of established methodologies capable of handling the increasing volumes of E-waste pose a severe environmental threat. Among the challenges to successful electronic equipment recycling, printed circuit board (PCB, primary components in every type of electronic product) recycling is recognized as one of the most difficult problems because of the complex construction and complicated materials composition of PCBs. The current PCB recycling industry uses traditional metallurgical technologies in which the fiber reinforced polymer matrix materials are incinerated. Although great effort has been made in the traditional metallurgical technologies for increasing the recycling efficiency for the end-of-life electronic products, the PCB recycling industry still faces the problems of poor environmental performance and limited economic returns. Recently, under an EAGER grant, the PIs of this award demonstrated proof-of-concept preliminary work for developing a novel supercritical fluid (SCF) CO2-based PCB recycling process at relatively low/medium temperatures and pressures. The exploratory experiments demonstrated that PCBs are delaminated with metals and glass fiber maintain their original form, making it possible to increase recovery rates not only for precious metals but also for non-metal materials. Such a process opens a new dimension for recycling of PCB and provides the possibility of satisfying economical and environmental demands. In the current project, the research team will systematically investigate the delamination mechanism of the bonding materials in PCBs under supercritical fluid processes and seek to understand structure/process relationships. Although literature documents the application of supercritical fluids in polymer synthesis and processing, there is limited existing work on revealing the performance of polymeric materials in supercritical fluids. In addition, the research team will optimize the SCF process by implementing process conditions based on the mechanism study and systematically evaluate process performance. Finally, the team will model and validate the recycling process for scale-up in terms of cost, energy, and environmental impact. The team will collaborate with industrial collaborators to promote transferring fundamental research to practical application. In addition, research and education will be integrated throughout the entire project duration.