Development of multiphase reactor technologies for the defossilization of commodity chemicals production

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Innovative technologies are urgently needed to address continuously growing global energy consumption. Chemical industries must adapt to achieve net-zero CO2 emissions by 2050. The integration of hydrocarbons in the chemical industry, largely producing carbon-rich compounds, makes complete decarbonization nearly impossible. Instead, the industry must immediately move towards defossilization, making use of renewable feedstocks (captured CO2 and sustainable hydrogen) to replace fossil-carbon feedstocks (i.e., crude oil, natural gas, and coal) to produce commodity chemicals. The proposed research program combines lab-scale experimental studies and modeling predictions for process scale-up to resolve the complex reaction networks and intricate transport phenomena required to design innovative CO2 conversion reactor technologies. Gas-liquid-solid (GLS) reactors are promising for converting sustainable feedstocks due to their reduced energy use by eliminating vaporization requirements as well as their operational flexibility with catalyst deactivation and/or the generation of immiscible liquid phases. The two objectives of the proposed research program include the development of heterogenous catalytic routes for CO2 conversion using GLS reactors, and interfacial area and flow behaviour predictions for the scale-up of CO2 conversion processes. CO2 can be converted to single carbon products (e.g., methanol) via direct hydrogen reduction. Conversion to chemicals with two or more carbons (e.g., alkanes, dimethyl ether, light olefins, higher alcohols) is also attractive based on their increased value. The first objective aims to overcome the persistent issues that hinder the adoption of industrial CO2 conversion to commodity chemicals by: (i) identifying water-tolerant catalysts, (ii) reducing catalyst costs while maintaining CO2 conversion and product selectivity; and (iii) exploring reactor configurations with in-situ water removal while considering thermodynamic limits. Gas-liquid transport phenomena also plays a critical role for these processes, where the gas-liquid mass transfer resistance is a crucial scale-up parameter. Extrapolation of lab-scale measurements to industrial-scale units with complex multicomponent liquids operating at elevated pressures and temperatures is still an unresolved challenge. The second objective will use pilot-scale experiments to measure micro-scale gas and solid flow characteristics under industrially relevant conditions. These will be combined with computational fluid dynamic simulations to advance interfacial area and flow behaviour predictions during scale-up, specifically for prospective CO2 conversion processes. Canada must significantly reduce its dependence on fossil-carbon materials in the next decade to meet its climate change goals. The proposed research program, focusing on the sustainable conversion of captured CO2, will provide the foundations required to move towards chemical industry defossilization.