Carboxycellulose Nanofibers from Underutilized Biomasses for Water Purification

非技术概述：本项目旨在加深我们对从各种未得到充分利用的生物质资源(如农业废弃物、草、杂草和灌木)中提取的羧基纤维素纳米纤维(CNF)的结构和性能关系的了解，并探索它们在净水方面的潜在用途。这一建议的学术价值包括：(1)利用简单的硝化氧化法，从低价值或无价值的生物质中制备新的、高价值的CNF基净水材料，在能源和化学节约方面具有显著的好处。(2)从合成和表征方面获得的基本知识，这些知识可以使使用碳纳米纤维作为有效的吸附剂和/或过滤材料的新的和创新的水净化技术朝着低成本和可持续的水处理方向发展。该项目将为研究生和本科生提供跨学科培训，并为高中生和教师提供研究经验和推广机会。它还将与旨在改善人类生活质量的更广泛的可持续发展和清洁水活动相结合。技术摘要：本研究的目的是研究直接从广泛的未经处理(原始)生物质中制备的羧基纤维素纳米纤维(CNF)的胶体和流动行为。计划中的研究活动将包括调查结构、性质和化学条件的关系，以从各种未得到充分利用的非木材植物纤维资源中使用新开发的硝基氧化方法提取CNFS。在此基础上，研究了不同长宽比和电荷密度的碳纳米纤维在不同反离子价态、离子强度和pH值条件下的胶体行为和流动特性。将使用的技术主要是同步加速器X射线散射和高分辨率电子显微镜，结合混合流动池和流变学。最后，将使用CNFS作为吸附剂和/或过滤材料来开发新的净水技术，以处理广泛的水污染问题，特别是有毒金属离子的污染问题，以促进有效、低成本和可持续的水净化解决方案。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL SUMMARY:This project aims to enhance our understanding of the structure-and-property relationships of carboxycellulose nanofibers (CNFs) that can be extracted from a diverse range of underutilized biomass resources (e.g. agricultural waste, grass, weeds and shrubs), as well as explore their potential usage for water purification. The intellectual merit of this proposal entails: (1) The preparation of new, high-valued CNF-based water purification materials from low- or no-valued biomasses, using a simple nitro-oxidation method with significant benefits in terms of energy and chemical savings. (2) The fundamental knowledge gained from the synthetic and characterization aspects, which can enable the development of new and innovative water purification technologies using CNFs as effective adsorbents and/or filtration materials toward low-cost and sustainable water treatments. This project will provide interdisciplinary training to graduate and undergraduate students, as well as research experiences and outreach opportunities to high-school students and teachers. It will also be integrated with broader activities on sustainability and clean water aimed at improving the quality-of-life for humankind.TECHNICAL SUMMARY:The aim of this research is to investigate the colloidal and flow behavior of carboxycellulose nanofibers (CNFs) prepared directly from a broad range of untreated (raw) biomasses. The planned research activities will involve the investigation of the relationships of structure, property and chemical conditions for extraction of CNFs from varying underutilized non-wood plant fiber sources using a newly developed nitro-oxidation method. They will be followed by the study of the colloidal behavior and flow properties of extracted CNFs, consisting of different aspect ratios and charge densities, in aqueous suspensions, under different conditions of counterion valency, ionic strength and pH level. Techniques to be used will be primarily synchrotron X-ray scattering and high-resolution transmission electron microscopy in combination with mixing flow-cell and rheology. Lastly, new water purification technologies will be developed using CNFs as adsorbents and/or filtration materials to treat a broad range of water contamination problems, especially due to toxic metal ions, to advance effective, low-cost and sustainable water purification solutions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.