Li Mingyue, Xing Lei, Xu Zhongfei, Liang Zhengwei, Qi Tieyue, Li Yuchen, Zhang Shihan, Wang Lidong
MOE Key Laboratory of Resources and Environmental Systems Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, People's Republic of China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, People's Republic of China.
Environ Sci Technol. 2023 Oct 17;57(41):15465-15474. doi: 10.1021/acs.est.3c04916. Epub 2023 Oct 2.
Metal-molecular sieve composites with high acidity are promising solid acid catalysts (SACs) for accelerating sluggish CO desorption processes and reducing the energy consumption of CO chemisorption systems. However, the production of such SACs through conventional approaches such as loading or ion-exchange methods often leads to uncontrolled and unstable metal distribution on the catalysts, which limits their pore structure regulation and catalytic performance. In this study, we demonstrated a feasible strategy for improving the durability, surface chemical activity, and pore structure of metal-doped HZSM-5 through bimetallic Mo/Mn modification. This strategy involves the immobilization of Mo-O-Mn species confined in an MFI structure by regulating MoO anions and Mn cations. The embedded Mn/Mo species of low valence can strongly induce electron transfer and increase the density of compensatory H on the MoMn@H catalyst, thereby reducing the CO desorption temperature by 8.27 °C and energy consumption by 37% in comparison to a blank. The durability enhancement and activity regulation method used in this study is expected to advance the rational synthesis of metal-molecular sieve composites for energy-efficient CO capture using amine regeneration technology.
具有高酸度的金属-分子筛复合材料是用于加速缓慢的CO脱附过程和降低CO化学吸附系统能耗的有前途的固体酸催化剂(SAC)。然而,通过诸如负载或离子交换方法等传统方法生产此类SAC通常会导致催化剂上金属分布不受控制且不稳定,这限制了它们的孔结构调控和催化性能。在本研究中,我们展示了一种通过双金属Mo/Mn改性来提高金属掺杂HZSM-5的耐久性、表面化学活性和孔结构的可行策略。该策略涉及通过调节MoO阴离子和Mn阳离子来固定限制在MFI结构中的Mo-O-Mn物种。与空白相比,低价态的嵌入Mn/Mo物种能强烈诱导电子转移并增加MoMn@H催化剂上补偿性H的密度,从而使CO脱附温度降低8.27°C,能耗降低37%。本研究中使用的耐久性增强和活性调控方法有望推动用于采用胺再生技术进行节能CO捕集的金属-分子筛复合材料的合理合成。