Williams Peter J H, Killeen Charles, Chagunda Ian C, Henderson Brett, Donnecke Sofia, Munro Wil, Sidhu Jaspreet, Kraft Denaisha, Harrington David A, McIndoe J Scott
Department of Chemistry, University of Victoria PO Box 1700 STN CSC Victoria BC V8W 2Y2 Canada
Chem Sci. 2023 Aug 24;14(36):9970-9977. doi: 10.1039/d3sc02698a. eCollection 2023 Sep 20.
Kinetic analysis of catalytic reactions is a powerful tool for mechanistic elucidation but is often challenging to perform, limiting understanding and therefore development of these reactions. Establishing order in a catalyst is usually achieved by running several reactions at different loadings, which is both time-consuming and complicated by the challenge of maintaining consistent run-to-run experimental conditions. Continuous addition kinetic elucidation (CAKE) was developed to circumvent these issues by continuously injecting a catalyst into a reaction, while monitoring reaction progress over time. For reactions that are th order in a single yield-limiting reactant and th order in catalyst, a plot of reactant concentration against time has a shape dependent only on the orders and . Therefore, fitting experimental CAKE data (using open access code or a convenient web tool) allows the reactant and catalyst orders, rate constant, and the amount of complete catalyst inhibition to be determined from a single experiment. Kinetic information obtained from CAKE experiments showed good agreement with the literature.
催化反应的动力学分析是阐明反应机理的有力工具,但通常实施起来具有挑战性,这限制了对这些反应的理解以及相应的发展。确定催化剂的级数通常是通过在不同负载量下进行多个反应来实现的,这既耗时,又因要保持每次实验条件一致而变得复杂。连续添加动力学阐明法(CAKE)的开发是为了规避这些问题,该方法通过将催化剂连续注入反应体系,同时监测反应随时间的进程。对于在单一产率限制反应物中为(n)级且在催化剂中为(m)级的反应,反应物浓度随时间的曲线形状仅取决于(n)和(m)。因此,拟合实验CAKE数据(使用开放获取代码或便捷的网络工具)可以从单个实验中确定反应物和催化剂的级数、速率常数以及完全催化剂抑制量。从CAKE实验获得的动力学信息与文献显示出良好的一致性。