Conversion/Recycling of Ethylene-Based Copolymers: Is it Feasible in SCF-Water Mixtures (SGER)

9509608麦克休回收聚合物和共聚物是一个必须解决的技术问题，如果要减少美国填埋的固体废物的数量。挑战是开发以经济的方式进行回收的技术，而不会产生会否定任何环境效益的溶剂废物。许多研究人员建议使用超临界水将聚合物分解成它们的积木。在这个项目中，建议了一种不同的方案，将共聚物转化为一种替代结构，该结构可能比原始材料具有更高的商业价值。设想的转换过程将使用近临界水而不是超临界水，这将减少该过程的热能需求。各种聚合物和共聚物在近临界溶液中的溶解特性的差异将有助于将一种类型的共聚物从另一种类型中分离出来。这一新的转化/回收工艺的成功开发在很大程度上取决于对这些共聚物在工艺溶剂溶液中的良好理解。然而，这项拟议研究的重点是确定这些想法的可行性，而不是深入了解这一过程的热力学和动力学。将进行选定的溶解度和动力学实验，以突出这一过程的潜力。这一新工艺概念的成功论证将为制定一项更详细的提案奠定基础，以确定确保该工艺经济可行性的热力学、动力学和分离变量。

9509608 McHugh Recycling polymers and copolymers is a technological problem that must be addressed if the amount of solid waste being landfilled in the United States is to be reduced. The challenge is to develop technology that performs the recycling in an economic manner without the concomitant generation of solvent waste that would negate any environmental benefits. Many researchers have suggested decomposing polymers into their building blocks using supercritical water. a different scenario is suggested in this program where the copolymer is converted into an alternate structure that potentially has higher commercial value than the starting material. The envisioned conversion process would use near-critical water rather than supercritical water which reduces the thermal energy requirements of the process. The differences in the solubility characteristics of the various polymers and copolymers in the near-critical solution would facilitate separating one type of copolymer from another. The successful development of this new conversion/recycling process to a great extent depends on a good understanding of these copolymers in the process solvent solution. However, the focus of this proposed study is to determine the feasibility of these ideas rather than to develop an in-depth understanding of the thermodynamics and kinetics of the process. Selected solubility and kinetics experiments will be performed to highlight the potential of this process. The successful demonstration of the concepts for this new process would create the groundwork for the development of a more detailed proposal to determine the thermodynamic, kinetic, and separations variables that would insure the economic viability of the process.