Sharma Arisha, Biswas Prakash, Singh Meenesh R
Department of Chemical Engineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India.
Department of Chemical Engineering, University of Illinois Chicago, Chicago, Illinois 60607, United States.
ACS Appl Mater Interfaces. 2024 Dec 11;16(49):67620-67634. doi: 10.1021/acsami.4c12538. Epub 2024 Nov 26.
Tri-reforming methane with CO, O, and HO mixtures requires a delicate balance of dry-reforming, partial oxidation, and steam-reforming reactions to improve the CO conversion and H/CO ratio. Nickel-alumina has been reported before for the tri-reforming of methane, although at higher temperatures (>900 °C). This is because the current approaches for nickel-alumina synthesis are ineffective in generating stronger catalyst-support interactions necessary to maintain higher active sites and stall carbon nanotube (CNT) deposition. Here, we report a synthesis method that allows controlled loading of nickel on alumina-based MIL-53 metal-organic framework followed by calcination to generate 2.5-10 wt % nickel nanoparticles dispersed on alumina. The 5 wt % nickel-alumina mixtures resulted in nanometer-sized crystallites, better metal dispersion, and more active sites for enhanced catalytic activity. This optimal loading of nickel allows stronger interaction with alumina for over 100 h of stable performance of tri-reforming at 800 °C, achieving ∼98% CH conversion, ∼36% CO conversion, and no carbon deposition while producing Fischer-Tropsch-ready feed containing a H/CO ratio of 3.2.
用CO、O和H₂O混合物对甲烷进行三重整,需要干重整、部分氧化和蒸汽重整反应之间达到微妙的平衡,以提高CO转化率和H₂/CO比。之前已有关于镍 - 氧化铝用于甲烷三重整的报道,不过是在较高温度(>900 °C)下。这是因为目前合成镍 - 氧化铝的方法在产生维持更高活性位点和阻止碳纳米管(CNT)沉积所需的更强催化剂 - 载体相互作用方面效率不高。在此,我们报道一种合成方法,该方法允许在氧化铝基MIL - 53金属有机框架上可控负载镍,随后进行煅烧,以生成分散在氧化铝上的2.5 - 10 wt%的镍纳米颗粒。5 wt%的镍 - 氧化铝混合物产生了纳米尺寸的微晶、更好的金属分散性以及更多用于增强催化活性的活性位点。这种镍最佳负载量使得与氧化铝有更强的相互作用,在800 °C下实现了超过100小时的三重整稳定性能,实现了约98%的CH₄转化率、约36%的CO转化率,且无碳沉积,同时生成了H₂/CO比为3.2的费托合成可用原料。