Collaborative Research: Rational design of Ni/Ga intermetallic compounds for efficient light alkanes conversion through ammonia reforming

廉价和丰富的轻质烷烃（来自天然气）的转化可能对化学和能源部门产生深远的影响，但由于缺乏有效的催化剂/催化系统，仍然是一个艰巨的挑战。在过去的几十年里，烷烃转化为一系列石化产品的各种工艺已经得到了广泛的研究，但只有蒸汽甲烷重整、丙烷脱氢和蒸汽乙烷非催化裂化被大规模生产。该项目探索了一种替代现有的催化系统，即轻烷烃的氨辅助重整（氨形成）。氨形成是指氨（NH3）与轻烷烃（如乙烷，C3H8）反应生成氰化氢（HCN——一种重要的工业化学品）和氢（H2）。值得注意的是，该反应避免了一氧化碳或二氧化碳的产生，从而为碳的循环使用奠定了基础，同时产生的温室气体最少。该项目将加强密西西比州立大学和北伊利诺伊大学在化学/化学工程方面的学术研究和教育项目。该项目利用了两所大学的几个项目，旨在激发K-12学生对STEM职业的兴趣，并为代表性不足的本科生提供发展研究技能的机会。本项目通过对轻烷烃氨形成的结构/性能关系和催化机理的了解，重点设计和合成高效的非贵金属- NixGay金属间化合物（IMC）基催化剂。该项目重点研究了IMC催化剂的氨形成的几个基本方面，包括：(1)了解草酸盐前驱体的组成对NixGay IMC催化剂的结构、表面性质和粒径的影响及其与乙烷氨形成的催化性能的关系；(2)了解草酸盐热分解和退火对NixGay催化剂结构、表面性能和催化性能的影响；(3)阐明反应诱导的表面/体重构，确定表面反应中间体和催化机理。该研究将通过Argonne国家实验室先进光子源的原位/operando x射线表征（包括XRD， SAXS和XAS）， operando drift - ms和弛豫型瞬态实验相结合进行。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。

The transformation of cheap and abundant light alkanes (from natural gas) could have far-reaching implications on the chemical and energy sectors yet remains a formidable challenge due to the lack of efficient catalysts/catalytic systems. While various processes for alkane transformation to a host of petrochemical products have been extensively studied during the past decades, only steam methane reforming, propane dehydrogenation, and steam ethane noncatalytic cracking are produced at large-scale. This project explores an alternative to current catalytic systems known as ammonia-assisted reforming (ammoreforming) of light alkanes. Ammoreforming involves reacting ammonia (NH3) with a light alkane (such as ethane, C3H8) to produce hydrogen cyanide (HCN – an important industrial chemical) and hydrogen (H2). Significantly, the reaction avoids production of either carbon monoxide or carbon dioxide, thus setting the stage for circular usage of carbon with minimal generation of greenhouse gas. The project will strengthen academic research and educational programs in chemistry/chemical engineering at both Mississippi State University and Northern Illinois University. The project leverages several programs at both institutions aimed at stimulating K-12 students’ interest in STEM careers and providing underrepresented undergraduates opportunities to develop research skills.The project focuses on the design and synthesis of efficient non-noble metal - NixGay intermetallic compound (IMC) based catalysts - by the understanding of the structure/performance relationships and catalytic mechanisms of the ammoreforming of light alkanes. The project focuses on several fundamental aspects of ammoreforming over the IMC catalysts, including (1) understanding the effect of oxalate precursor’s composition on the structure, surface properties, and particle size of the NixGay IMC catalysts and their relationships to the catalytic performance of ethane ammoreforming; (2) understanding the influence of oxalate thermo-decomposition and annealing on the structure and surface properties of the NixGay catalysts and the catalytic performance; (3) elucidating the reaction-induced surface/bulk reconstruction and identifying the surface reaction intermediates and catalytic mechanism. The research will be carried out through the combination of in-situ/operando X-ray characterizations (including XRD, SAXS, and XAS) at the Advanced Photon Source of Argonne National Laboratory, operando-DRIFT-MS, and relaxation type transient experiments.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.