NER: Carbon Nanotube Synthesis: Assessing Economic and Environmental Tradeoffs in Process Design

该提案是响应纳米尺度科学与工程计划，NSF 03-043， NER类别而收到的。碳纳米管的非凡特性（如电气、机械和化学特性）导致了药物输送和医疗诊断应用方面的研究，并为提供新的和改进的环境技术提供了巨大的希望。然而，似乎很少有研究人员在这些工艺的发展中包括绿色工程原则，并且随着对纳米技术发展的普遍关注，在工艺处于发展阶段时评估工艺选择的权衡将是谨慎的，以允许创建更可持续的工艺。因此，这个项目解决了纳米技术的社会影响。纳米技术潜在的有害社会影响已经产生了政策分析和立法国会听证会。许多组织已经响应了解决潜在后果的需要，包括国家纳米技术计划、环境保护署（EPA）和国家工程院（NAE），通过举办研讨会和座谈会来解决跨学科边界的问题。一份关于负责任的纳米技术开发实践指导方针的文件草案可以在前瞻研究所的网站上找到，但是大多数科学家和工程师并不知道它的存在。尽管该文件包括一些具体的建议，旨在为分子纳米技术的负责任的发展提供基础，但它没有解决研究人员评估负责任的工艺设计的方法。拟议的研究解决了这一需求。考虑到使用单壁碳纳米管（SWNTs）的潜在好处和担忧，本提案侧重于评估单壁碳纳米管合成的技术、环境和经济特征之间的权衡。在一项为期一年的纳米探索研究（NER）合作计划中，东北大学（NU）和维克森林大学（WFU）的主要研究人员将收集有关单壁纳米管（SWNT）工艺的相关信息：生产的产品、使用的材料、排放到环境中的废水和使用的能源。WFU将提供这些信息，以便为其SWNT工艺编制清单。NU将开发生命周期分析（LCA）方法来跟踪材料。北大将从WFU收集工艺技术信息，开发技术成本模型，以评估大规模操作的工艺经济，包括污水处理的环境成本和工人安全。成本模型将包括有形的环境过程成本。WFU将跟踪实验室规模的SWNT电弧、CVD和激光辅助CVD工艺的环境方面，涉及SWNT生产的能源利用、废气排放、固体废物产生和可能的空气危害。基于NU的过程改进建模结果，WFU将进行试验并对最终产品进行表征。北大和WFU将合作评估投入并确定最环保的SWNT合成方法的初步结果。pi的专业知识是互补的。西北大学在LCA和TCM模型的成功开发和利用方面有着悠久的历史，而WFU在开发各种类型的单壁纳米管的替代工艺方面处于领先地位。考虑到使用单壁碳纳米管的潜在好处和问题，以及许多新的（和现有的）企业目前正在努力将该工艺商业化，对技术、环境和经济特征之间的权衡进行评估至关重要。这项工作的智力价值在于将绿色工程原理应用于开发纳米技术。环境友好型纳米技术工艺设计的发展具有重要的广泛影响。这个为期一年的项目的结果预计将提供关于替代工艺选择的信息，这将允许研究人员和工艺开发人员做出明智的决定，以适当地使用和扩大该技术。通过这个项目，实验室研究人员、研究生和本科生（通过课程模块）将意识到相关的社会和伦理问题，并可以在过程开发过程中进行适当的权衡。通过现有的NSEC和MRSEC中心传播这项工作将使其他研究人员熟悉无害环境的工艺设计实践。

This proposal was received in response to Nanoscale Science and Engineering initiative, NSF 03-043, category NER. The extraordinary properties of carbon nanotubes (e.g., electrical, mechanical and chemical) have led to research in drug delivery and medical diagnostic applications, and offer great promise for delivering new and improved environmental technologies. However, it appears that few researchers are including green engineering principles in the development of these processes, and with the general concern over nanotech development, it would be prudent to assess the tradeoffs in process alternatives while the processes are in their developmental phases, to allow creation of more sustainable processes. This project therefore addresses societal implications of nanotechnology. The potential for harmful societal implications of nanotechnology has generated policy analyses and legislative congressional hearings. Many organizations have been responsive to the need to address potential consequences, including the National Nanotechnology Initiative, the Environmental Protection Agency (EPA) and the National Academy of Engineering (NAE), by holding workshops, and colloquia to address issues that cross disciplinary boundaries. A draft document on guidelines for responsible nanotechnology development practices is available on the Foresight Institute's website, but most scientists and engineers are not aware of its existence. Although the document includes some specific recommendations intended to provide a basis for responsible development of molecular nanotechnology, it does not address methods for researchers to assess responsible process design. The proposed research addresses this need. Given the potential benefits and concerns over the use of single wall carbon nanotubes (SWNTs), this proposal focuses on assessment of the tradeoffs among the technological, environmental and economic characteristics of SWNT synthesis. In a collaborative one-year Nano Exploratory Research (NER) plan, the principal investigators at Northeastern University (NU) and Wake Forest University (WFU) will gather pertinent information on single wall nanotube (SWNT) processes: products created, materials used, effluents generated to the environment, and energy used. WFU will provide this information to develop inventories for their SWNT processes. NU will develop life cycle analysis (LCA) approaches to track materials. NU will gather technical process information from WFU to develop technical cost models (TCMs) to assess the process economics for scaled-up operations, including environmental costs for effluent disposal and worker safety. The cost models will include tangible environmental process costs. WFU will track environmental aspects of lab-scale SWNT arc, CVD, and laser-assisted CVD processes with regard to energy utilized, waste gas emissions, solid waste production and possible airborne hazards for production of SWNTs. Based on NU's modeling results for process improvement, WFU will run trial experiments and characterize the resulting products. NU and WFU will collaboratively assess inputs and determine preliminary results for the most environmentally benign approaches to SWNT synthesis. The expertise of the PIs is complementary. NU has a track record of successful development and utilization of LCA and TCM models, while WFU is a leader in the development of process alternatives for the synthesis of various types of single-walled nanotubes. Given the potential benefits and concerns over the use of SWNTs, and the fact that many new (and existing) businesses are currently working to commercialize the process, assessment of the tradeoffs among the technological, environmental and economic characteristics is critical. The intellectual merit in this work resides in the application of green engineering principles to developmental nanotechnologies. There is significant broader impact associated with the development of environmentally benign nanotech process design. Results from this one-year project are expected to provide information on alternative process choices that will allow researchers and process developers to make informed decisions for appropriate use and scale-up of the technology. Through this project, laboratory researchers, graduate students and undergraduates (through a course module) will become aware of the associated societal and ethical issues, and can work to incorporate appropriate tradeoffs during process development. Dissemination of this work through the existing NSEC and MRSEC Centers will allow other researchers to become familiar with environmentally benign process design practices.