Carboxycellulose Nanofibers from Underutilized Biomasses for Water Purification

非技术总结：该项目旨在增强我们对羧基纤维素纳米纤维（CNFs）结构和性质关系的理解，这些纤维可以从各种未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，并探索它们在水净化方面的潜在用途。这一建议的智力价值包括：(1)从低价值或无价值的生物质中制备新的、高价值的基于cnf的水净化材料，使用简单的氮氧化方法，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础知识，可以使使用CNFs作为有效吸附剂和/或过滤材料的新型创新水净化技术的发展成为低成本和可持续的水处理。该项目将为研究生和本科生提供跨学科培训，并为高中学生和教师提供研究经验和拓展机会。它还将与旨在改善人类生活质量的更广泛的可持续性和清洁水活动结合起来。技术概述：本研究的目的是研究羧基纤维素纳米纤维（CNFs）的胶体和流动行为，这些纤维是由广泛的未经处理的（原料）生物质直接制备的。计划的研究活动将包括调查利用新开发的硝基氧化法从各种未充分利用的非木质植物纤维来源提取CNFs的结构、性质和化学条件之间的关系。随后，他们将研究不同长径比和电荷密度下提取的CNFs在不同反离子价、离子强度和pH水平下在水悬浮液中的胶体行为和流动特性。使用的技术将主要是同步加速器x射线散射和高分辨率透射电子显微镜，结合混合流动池和流变学。最后，将开发新的水净化技术，使用CNFs作为吸附剂和/或过滤材料来处理广泛的水污染问题，特别是由于有毒金属离子，以推进有效，低成本和可持续的水净化解决方案。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.