Retrievable and Reusable Nanoparticle-Pinched Polymer Brushes Enable Highly Efficient Microalgae Dewatering for Cost-Effective Biofuel Production

可回收和可重复使用的纳米颗粒挤压聚合物刷可实现高效微藻脱水，从而实现具有成本效益的生物燃料生产

• 批准号: 1160291
• 负责人: Hongjun Liang
• 金额: $ 29.9万
• 依托单位: Colorado School of Mines
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2016-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1160291&HistoricalAwards=false
• 关键词: Retrievable; Reusable; Nanoparticle; Pinched; Polymer

1160291LiangVarious analyses based on the production rate and environmental considerations have suggested that biofuels from microalgae are likely the only realistic substitute capable of releasing our reliance on fossil fuels. Despite decades of effort, commercial production of microalgae-derived biofuels has not emerged because current technologies for microalgae dewatering add a huge cost to the final product, and present a major barrier between algaculture and biofuels. A knowledge gap exists in the underlying principles governing microalgae dewatering, particularly for the rational design of coagulation agents. The long-term goal of the proposed work is to understand the underlying principles that govern the stability of a colloidal suspension of living cells, and to direct the phase separation of free-floating cells in a controllable fashion. The overall objective of this proposal is to identify the rational correlations between inter-algal pair interactions and coagulation-agent structures in order to achieve highly efficient microalgae dewatering at a negligible cost. The central hypothesis is that nanoparticle-pinched polymer brushes, i.e., radiating polymer chains covalently bonded to a nanoparticulate core, are far more effective in dewatering microalgae than conventional flocculants; in addition, using solid-state nanoparticles allows low-cost operations (e.g., using magnetic fields) to be designed to collect algal biomass and retrieve the coagulation agents for multiple cycles of microalgae dewatering, which further reduces the operational cost significantly. We have formulated this hypothesis based on our strongly supportive preliminary data. The rationale underlying the proposed research is that, once the structural characteristics responsible for the unusually high performance of this novel coagulation agent are understood, precise control of its structure is expected to enable unprecedentedly cost-effective microalgae dewatering. Hence the bottleneck preventing commercialization of microalgae-derived biofuels will be cleared. We plan to test our central hypothesis and accomplish the overall objective of this application by pursuing the following three specific aims: 1. Identify a facile and highly efficient approach to synthesize paramagnetic nanoparticle-pinched polymer brushes with well-defined structures; 2. Determine how the microalgae dewatering efficiency is regulated by the structural characteristics of the coagulation agents; 3. Determine the efficiency of retrieving nanoparticle-pinched polymer brushes for continuous cycles of microalgae growth and dewatering. The expected contribution of this work is to determine the structural characteristics of engineered coagulation agents that endow them with an unusually high efficiency in microalgae dewatering and an unusually low operational cost. This contribution is significant, because it creates a class of super coagulation agents via examining rational correlations between inter-algal pair interactions and flocculants of well-defined structures. This aspect has been poorly understood despite decades of relentless trial-and-error experiments with commercially available chemicals. Energy and environment represent the top challenges for the sustainable development of our societies. It is well understood that securing renewable energy sources is the grand challenge of our time, but it is not always recognized that any engineered material proposed to address that challenge must be sustainable itself, an example is the design of microalgae coagulation agent in this application. The researchers plan to bring broad societal awareness on this aspect with the following integrated activities: Incorporating research into teaching. The assembled research team will be a nucleus to enhance biofuel research at Mines by giving seminars, developing course materials, and attracting industry sponsorship. The PI will build a webpage devoted to microalgae harvesting issues, and disseminate the video clips of microalgae dewatering experiments to Youtube to advertise sustainable materials for sustainable energy; Outreach to Underrepresented Groups. The researchers plan to build a focused and sustainable outreach program by developing lecture materials and classroom demonstration experiments on algal biofuels, which will be used by the PI and his graduate students, to participate in an existing outreach program at Mines that spans grades kindergarten through the twelfth in two school districts, Adams County District 50 (AC50) and Meeker County (MC). Both school districts are rurally located and have a high proportion of students who are living in poverty

1160291Liang基于生产率和环境考虑的各种分析表明，微藻生物燃料可能是唯一能够摆脱我们对化石燃料依赖的现实替代品。尽管经过数十年的努力，微藻衍生生物燃料的商业化生产尚未出现，因为现有的微藻脱水技术给最终产品增加了巨大的成本，并在藻类养殖和生物燃料之间形成了主要障碍。微藻脱水的基本原理存在知识差距，特别是在混凝剂的合理设计方面。这项工作的长期目标是了解控制活细胞胶体悬浮液稳定性的基本原理，并以可控的方式指导自由漂浮细胞的相分离。该提案的总体目标是确定藻类间相互作用和混凝剂结构之间的合理相关性，以便以可忽略的成本实现高效的微藻脱水。中心假设是，纳米颗粒挤压聚合物刷，即共价键合到纳米颗粒核心的辐射聚合物链，在微藻脱水方面比传统絮凝剂更有效。此外，使用固态纳米粒子可以设计低成本操作（例如使用磁场）来收集藻类生物质并回收用于微藻脱水的多个循环的凝结剂，这进一步显着降低了操作成本。我们根据强有力的初步数据制定了这一假设。这项研究的基本原理是，一旦了解了这种新型混凝剂具有异常高性能的结构特征，对其结构的精确控制有望实现前所未有的经济高效的微藻脱水。因此，阻碍微藻生物燃料商业化的瓶颈将被消除。我们计划通过追求以下三个具体目标来测试我们的中心假设并实现该应用的总体目标： 1. 确定一种简便高效的方法来合成具有明确结构的顺磁性纳米颗粒挤压聚合物刷； 2.确定混凝剂的结构特征如何调控微藻脱水效率； 3. 确定回收纳米颗粒挤压聚合物刷以实现微藻生长和脱水连续循环的效率。这项工作的预期贡献是确定工程混凝剂的结构特征，使其在微藻脱水方面具有异常高的效率和异常低的运营成本。这一贡献是重要的，因为它通过检查藻类间相互作用和结构明确的絮凝剂之间的合理相关性创建了一类超级混凝剂。尽管人们对市售化学品进行了数十年的不断试错实验，但人们对这一方面的了解却知之甚少。能源和环境是我们社会可持续发展的首要挑战。众所周知，确保可再生能源是我们这个时代面临的巨大挑战，但人们并不总是认识到为应对这一挑战而提出的任何工程材料本身都必须是可持续的，一个例子就是该应用中微藻凝结剂的设计。研究人员计划通过以下综合活动提高社会对此方面的广泛认识： 将研究纳入教学。组建的研究团队将通过举办研讨会、开发课程材料和吸引行业赞助，成为加强矿山生物燃料研究的核心。 PI将建立一个专门讨论微藻收获问题的网页，并将微藻脱水实验的视频片段传播到Youtube，为可持续能源宣传可持续材料；向代表性不足的群体伸出援手。研究人员计划通过开发关于藻类生物燃料的讲座材料和课堂演示实验来建立一个有针对性和可持续的外展计划，这些材料将供 PI 和他的研究生使用，以参与矿山现有的外展项目，该项目涵盖幼儿园到年级。在亚当斯县第 50 学区 (AC50) 和米克县 (MC) 两个学区中排名第十二。两个学区均位于农村地区，贫困学生比例很高

项目成果

Interface for Light-Driven Electron Transfer by Photosynthetic Complexes Across Block Copolymer Membranes

• DOI: 10.1021/jz402766y
• 发表时间: 2014-03-06
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY LETTERS
• 影响因子: 5.7
• 作者: Kuang, Liangju;Olson, Tien L.;Liang, Hongjun
• 通讯作者: Liang, Hongjun