Collaborative research: SusChEM: Hybrid mixed-resolution solvation models for chemical processing in ionic liquids

1605744 / 1604369 pi: Ismail, Ahmed / Bardhan， Jaydeep机构：西弗吉尼亚大学研究公司/东北大学标题：合作研究：SusCHEM；用纤维素质生物质原料大规模替代石油原料的主要瓶颈是将天然生物质转化为工业原料所必需的物理、化学和生物预处理所带来的困难。虽然机械和生物预处理途径在很大程度上已经得到了很好的理解，但在如何化学预处理生物质以实现进一步加工方面仍存在很大的不确定性。这个合作项目的目标是推进分子溶剂化的多尺度模型，以更好地了解纤维素生物质在离子液体中的溶解。离子液体是一类重要的材料，具有广泛的应用范围。该项目将(i)将多尺度溶剂模型应用于离子液体；（ii）建立使用x射线溶液散射实验来验证多尺度模型；（iii）应用这些模型来理解为什么低浓度的溶解水会限制纤维素的溶解；（iv）将研究与教育和外展工作相结合，以促进跨学科培训和扩大STEM参与。提出的研究将阐明离子液体结构和性能之间的基本关系，以及这些关系如何依赖于温度和含水量。在离子液体的化学处理过程中，这些依赖关系是实现离子液体合理工程的关键。即将开发的计算技术将使用一种新颖的多尺度方法将微观细节与宏观行为联系起来，从而大大降低与原子分子动力学和粗粒度模拟相关的计算成本。通过减少系统中存在的原子数量，计算静电力的成本（带电系统分子动力学模拟的主要成本）将大大降低，从而允许使用相同的可用计算资源进行更大、更长的模拟。这种方法将允许对离子液体和纤维素之间的相互作用进行比目前可能更深入的研究。最终目标是确定选择离子液体的主要标准，这将使设计更经济、更有效的纤维素溶解化学工艺成为可能。

1605744 / 1604369 PIs: Ismail, Ahmed / Bardhan, Jaydeep Institution: West Virginia University Research Corporation / Northeastern UniversityTitle: Collaborative Research: SusCHEM: Hybrid mixed-resolution solvation models for chemical processing in ionic liquidsA major bottleneck in the quest for large-scale replacement of petroleum feedstocks with ones derived from cellulosic biomass is the difficulty posed by the physical, chemical, and biological pretreatments that are necessary for converting the native biomass into industrially-useful feedstocks. And while the mechanical and biological pretreatment routes are largely well understood, substantial uncertainty remains in how to chemically pretreat biomass to enable further processing. The goal of this collaborative project is to advance multiscale models of molecular solvation to better understand dissolution of cellulosic biomass in ionic liquids. Ionic liquids are an important class of materials, which have a broad spectrum of applications. The project will (i) apply multiscale solvent models to ionic liquids; (ii) establish the use of X-ray solution scattering experiments to validate multiscale models; (iii) apply these models to understand why small concentrations of dissolved water limit cellulose dissolution; and (iv) integrate research with education and outreach efforts to advance cross-disciplinary training and broaden STEM participation.The proposed research will elucidate the fundamental relationships between ionic liquid structure and performance, and how these relationships depend on temperature and water content. These dependencies are key to enabling the rational engineering of ionic liquids for robust performance during chemical processing in ionic liquids. The computational techniques that will be developed will link the microscopic details with macroscopic behavior using a novel multiscale approach that drastically reduces the computational costs associated with atomistic molecular dynamics and coarse-grained simulations. By reducing the number of atoms present in the system, the cost of calculating electrostatic forces, the dominant cost in molecular dynamics simulations of charged systems, will be greatly reduced, allowing for much larger and longer simulations with the same set of available computational resources. This approach will allow for much more in-depth studies of the interactions between ionic liquids and cellulose than is currently possible. The ultimate objective is the identification of the dominant criteria for selecting ionic liquids that will enable the design of more economical and more efficient chemical processes for cellulose dissolution.