CAREER: Engineering Circular Hydrocarbon Reactions in Zeolite-based Catalysts

职业：在沸石基催化剂中设计循环碳氢化合物反应

• 批准号: 2338497
• 负责人: Michele Sarazen
• 金额: $ 57.53万
• 依托单位: Princeton University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-02-01 至 2029-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2338497&HistoricalAwards=false
• 关键词: CAREER; Engineering; Circular; Hydrocarbon; Reactions

Chemical processes that breakdown plastic waste and remanufacture the deconstructed products to valuable fuels and chemicals are attractive alternatives to fossil-fuels for hard-to-decarbonize sectors such as aviation fuels. Such plastic upcycling is especially valuable when it can be achieved at moderate temperatures in energy efficient processes. Catalysts offer a route to that end by lowering reaction temperature and selectively directing conversion of plastic to products that serve as building blocks for a broad range of fuels, consumer goods, pharmaceuticals, and building materials, to name a few. Zeolites are a class of porous crystalline catalysts that are especially suitable for waste plastic deconstruction, but further research and development is needed to improve their efficiency, product selectivity, and durability. Thus, this project investigates key design factors that affect the overall effectiveness of zeolite catalysts for the breakdown of a prevalent class of waste plastic, polyolefins. The project is supported by integrated educational and outreach activities aimed primarily at undergraduate and graduate students.While catalysts are ubiquitous in the production of fuels and important chemical intermediates, the design of advanced catalysts that possess high reactivity, selectivity, and stability remains paramount for efficiently and sustainably abating pollution while lowering energy demands and decreasing carbon emissions. Here, this rational design is employed in the hydrocracking of polyolefins using bifunctional metal/zeolite catalysts, where zeolitic voids simultaneously provide high reactivity and tailored selectivity, but limit catalyst efficiency and stability due to diffusional constraints of bulky products. Hierarchical zeolites with hybrid pore structures can be utilized to address this inaccessibility of bulky polymer molecules, but the direct effect on reaction and deactivation mechanisms, especially of these complex multiphase systems is not well-established. The project thus aims to engineer hierarchical (bifunctional) zeolites in selective hydrocracking of waste polyolefins, based on hypotheses that enhancements of hierarchical structuring affect reaction and deactivation rates for polyolefin cracking beyond simple diffusional impacts and include effects of pore structure (i.e., zeolite framework), connectivity, communication (metal:acid balance/proximity) and reactions occurring within the mesoporous regions and surface protons. By combining synthetic protocols with detailed reaction pathway and deactivation analysis, the project will reveal new insights on how shape-selectivity and transport phenomena affect the performance of these hierarchical, bifunctional catalysts for transformation of waste polyolefins into useful products. Those insights will aid in understanding the entire catalytic lifecycle, including specific mechanistic details that can be extended to improve catalyst efficiency for reactions of various feedstocks related to hydrocarbon and oxygenate processing (i.e., biomass, renewable alcohols, or CO2) and different zeolite or zeotype architectures. Research results from this award will be proactively incorporated into an undergraduate elective entitled Green and Catalytic Chemistry that will incorporate interactive components like hands-on catalysis (plastic upcycling and aqueous pollutant degradation) and separation (CO2 capture) experiments, and “Sustainability Spotlights” based on media articles covering energy and climate related topics. The project will also strengthen the broader catalysis community through “CatChats” for younger graduate students in catalysis labs at various universities. These meetups will create a supportive network of peers, via initial virtual connections that will be expanded at conferences, workshops, and other in-person venues.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.

分解塑料废物和再制造的化学过程将解构的产品与有价值的燃料和化学物质是化石燃料的有吸引力的化石燃料替代品，用于难以确定的行业，例如航空燃料。当在节能过程中的现代温度下，这种塑料升级尤其有价值。催化剂通过降低反应温度并选择性地将塑料转换为作为广泛燃料，消费品，药品和建筑材料的构建产品的产品，提供了一条通往此目的的途径。沸石是一类多孔晶体催化剂，特别适合废塑料解构，但是需要进一步的研发来提高其效率，产品选择性和耐用性。这是该项目研究的关键设计因素，这些因素会影响沸石催化剂对普遍的废物塑料（聚烯烃）分解的总体有效性。该项目由主要针对本科生和研究生的综合教育和外展活动提供支持。催化剂在生产燃料和重要的化学中间体的生产中是无处不在的，而具有高反应性，选择性，选择性和稳定性的高级催化剂的设计仍然具有高效，可持续的降低污染，同时降低了能量的污染和降低能量的需求。在这里，这种合理的设计是在聚蛋白的加氢裂缝中使用双功能金属/沸石催化剂进行的，其中沸点空隙仅具有高反应性和量身定制的选择性，但由于不同块状产品的不同约束而限制了催化剂效率和稳定性。具有杂化孔结构的分层沸石可以用来解决这种笨重的聚合物分子的难以接近，但是对反应和失活机制的直接影响，尤其是这些复杂的多相系统的直接影响。 The project thus aims to engineer hierarchical (bifunctional) zeolites in selective hydrocracking of waste polyolefins, based on hypotheses that enhancements of hierarchical structuring affect reaction and deactivation rates for polyolefin cracking beyond simple diffusional impacts and include effects of pore structure (i.e., zeolite framework), connectivity, communication (metal:acid balance/proximity) and reactions occurring within介孔区域和表面质子。通过将综合方案与详细的反应途径和失活分析相结合，该项目将揭示有关形状选择性和运输现象如何影响这些层次结构的双功能催化剂的性能，以将废物聚烯烃转化为有用的产物。这些见解将有助于理解整个催化生命周期，包括可以扩展的特定机械细节，以提高与烃和氧化加工有关的各种原料的催化剂效率（即生物量，可再生酒精或CO2）以及不同的Zeolite或Zeolite或Zeotype型的架构。该奖项的研究结果将被积极地纳入本科选修课中，标题为“绿色和催化化学”，该化学将结合互动组件，例如动手催化（塑料升级和水性污染物降解）和分离（CO2捕获）实验，以及基于媒体艺术覆盖能量和气候相关的媒体艺术品的“可持续性聚光灯”。该项目还将通过“ Catchats”来加强更广泛的目录社区，以供各种大学目录实验室中的年轻研究生。这些聚会将通过最初的虚拟连接来建立一个受支持的同行网络，该网络将在会议，研讨会和其他面对面的地点扩展。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查标准通过评估来评估的。