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Carbon dioxide (CO2) utilization and conversion, as one of the main parts of carbon capture, utilization, and storage (CCUS), is not only considered an important way to mitigate global warming but also an attractive industrial route to produce valuable fuels and chemical feedstocks. Catalytic dry reforming of methane (DRM) is a promising technology for carbon dioxide utilization and conversion as it can produce syngas, carbon monoxide (CO), and hydrogen (H2) for widespread industrial production processes. In most studies of the DRM reaction, a relatively high operational temperature (i.e., >700°C) has been applied since the reactivity limitation of widely used Ni‐based catalysts at low temperatures and the extremely endothermic property of the DRM reaction. However, high cost and high requirement of thermal stability for catalysts have become a severe problem impeding the further commercialization of DRM technology. Decreasing the operational temperature (i.e., <700°C) is considered a promising way for further application of the DRM route to convert CO2 and produce syngas. However, traditional Ni‐based catalysts suffered from unsatisfied reactivity and severe coke formation, leading to quick deactivation at low temperatures. Developing a catalyst with excellent catalytic activity, coke resistance, and improved thermal stability is necessary for low‐temperature DRM reactions. In recent years, with significant development in materials, catalyst design, and computational simulation, some synthesized catalysts have achieved considerable improvement in catalytic performance in low‐temperature DRM. Hence, a review of recent development on low‐temperature DRM catalysts is provided here to further guide and profoundly understand catalyst design for low‐temperature DRM. [ABSTRACT FROM AUTHOR]

A novel ammonia vapour diffusion‐assisted impregnation technique was developed to synthesize the Al2O3‐MgO‐supported hierarchical Ni nanosheets. The resulting catalysts with different times for ammonia vapour treatments (at 12, 18, and 20 hours) were prepared to investigate the growth of Ni nanosheets on the catalyst surface. All catalysts were tested for CO2 reforming of methane and a comprehensive characterization study was conducted by XRD, N2 adsorption‐desorption, H2‐TPD, H2‐TPR, CO2‐TPD, and TGA. The Ni nanosheets were obtained using the ammonia vapour treatment for 20 hours, improving the selectivity toward H2 generation without a lower CH4 conversion. When compared to the reference catalyst prepared by a conventional impregnation method, the H2/CO ratio for CO2 reforming of the methane process was enhanced by 0.35. Additionally, the carbon deposition was reduced by half using hierarchical Ni nanosheets for the CO2 reforming of methane at 620°C for 20 hours. The mechanism of this improvement was achieved by the increase in medium basicity associated with a strong metal‐support interaction that promotes the CO2 activation‐dissociation pathways, preventing carbon formation and inhibiting the reverse water gas shift. [ABSTRACT FROM AUTHOR]

In the present paper, an optimization model is proposed for the ammonia synthesis reactor. The reversible exothermic reaction has nitrogen and hydrogen as reactants, at high temperatures, and high pressures with iron catalyst. Two different single‐objective optimization problems were considered, the maximization of the economic return and the maximization of the nitrogen conversion. The reaction rate model was defined as a function of partial pressures of the components. The problem was coded and solved in MATLAB using a derivative‐free method after reformulating a constrained optimization problem into an unconstrained one, by penalizing the infeasibilities of the constraints in the objective functions (barrier function). The main contributions of this paper are the combination of direct‐search methods in solving the optimization problem, the evaluation of the maximum ammonia production and the temperature profile. The optimal values found were better than the ones published in the literature. [ABSTRACT FROM AUTHOR]

Nitroxide mediated polymerization (NMP), sometimes known as stable free radical polymerization (SFRP), is considered one of the main types of reversible deactivation radical polymerization (RDRP) that have emerged as a major advance in polymer synthesis in the past 30 years. This review examines NMP's development from a uniquely Canadian perspective. Inspired by reports of a reversible equilibrium between the TEMPO persistent radical and a growing polymeric radical chain, researchers at the Xerox Research Centre of Canada (XRCC) reported radical polymerizations of styrene with hallmarks typically associated with living polymerizations: linear degree of polymerization of with conversion, narrow molecular weight distributions, and ability to re‐initiate the chain end with additional monomer. This effort expanded to polymerizations in dispersed aqueous media (eg, miniemulsion) and to polymerizations directed for various architectures (block, graft, star), but NMP was ultimately generally limited to styrenic monomers. Consequently, NMP trailed other RDRP methods, such as atom transfer radical polymerization (ATRP) and reversible addition fragmentation transfer polymerization (RAFT), due to its limited monomer choice. With the advent of second‐generation alkoxyamine initiators, however, the range of monomers polymerizable in a controlled manner greatly expanded to include acrylates, acrylamides, and eventually methacrylates (under certain conditions), providing renewed impetus towards using NMP. Consequently, Canadian researchers applied these new alkoxyamines for more versatile polymers, resulting in products such as stimuli‐responsive polymers, CO2‐switchable latexes, bio‐hybrid composites, organic photovoltaic materials, and photolithographic materials. The chronological progression of the developments in NMP from various Canadian laboratories highlights these achievements in new polymeric materials. [ABSTRACT FROM AUTHOR]