Moderating the activity of nickel and potassium catalysts for the gasification and activation of carbonaceous materials

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Catalysts are wonderful substances that enhance reaction rates, control the production of undesired products in chemical reactions, and contribute to over 35% of global gross domestic product. Used in over 90% of all industrial processes, catalysts reduce environmental impact by making the processes more energy and material efficient through the reduction of the severity of operating conditions and increased selectivity to the desired products, respectively. These processes can be made even more efficient and sustainable if the feeds and catalysts are obtained from materials that are otherwise viewed as waste, such as petroleum coke and forestry residues. Because the interactions between species are complex, however, unexpected results may be obtained by using wastes.***This proposal focuses on two related processes; namely, gasification and activation. Gasification is used to convert solids and liquids to gases that can be further used to produce power or other chemicals, while activation is used to convert carbonaceous materials into activated carbon for use as adsorbents and catalyst supports. During both processes, the carbon in the starting material (feed) is consumed to create a more porous material. In gasification, it is desirable to consume as much of the feed as possible, while in activation, only partial conversion of the feed occurs and the final product is a porous solid carbon with a surface area of at least several hundred metres squared per gram. Potassium and nickel are both excellent catalysts for gasification, and potassium catalysts are well used in the production of activated carbon. The challenges are that the catalysts can become deactivated and that the produced activated carbon often contains pores that are too small for the reaction of large hydrocarbons.***In this proposal, I would like to better understand how the interaction between potassium and nickel catalysts and a carbon surface (petroleum coke or model carbons) can be modulated by the introduction of modifiers (vanadium and calcium, etc.) to prevent deactivation during gasification and to result in larger pores during activation. Knowledge of these interactions will be applied when selecting and testing inexpensive, waste sources for the process feeds and catalysts. The use of these non-conventional sources will be beneficial in terms of both economic and environmental sustainability because materials are being reused/recycled, the process will be highly selective to the desired products, and the process energy requirements will be reduced.**