Novel Catalytic Steam Processing of Hydrocarbons: Partial Steam Reforming of Oils and Low-Temperature Steam Reforming
Creators: name: Moreno, Diego
Publisher: name: Arts
Year: 2024
Subjects: subject: Clean Hydrogen
subject: Low-Temperature Steam Reforming
subject: Renewable Natural Gas
subject: Catalytic Steam Cracking
subject: Naphthenic Acids
subject: Decarboxylation Reactions
subject: Energy
subject: Engineering--Chemical
subject: Engineering
subject: Engineering--Environmental

description: In our research group there were developed catalytic formulations to activate the water in hydrocarbon (HCs) reactions. This thesis takes a unique formulation that it is dedicated to evaluate its utility in upgrading of liquid and gaseous hydrocarbons while hydrogen generation is observed. When liquid HCs upgrading is the process selected, Naphthenic Acids (NAs) reduction is the process evaluated to verify the NAs reactivity and their reaction pathways. And when light gases are the feedstock selected, Steam Reforming (SR) is the process assessed to evaluate the utility of this catalyst to produce hydrogen at low temperature. Based on each feedstock/HC, there was formulated a specific catalyst. The catalysts comprise Ni-Ce-Mg-Al oxides, with textural properties of surface area and porous distribution that are adequate for each reactant. This thesis focuses on the path of catalytically activating water (as steam) to make use of its hydrogen content. This usage of steam in the fossil energy industry can go from hydroprocessing (moderate temperature process) replaced by steam processing, to hydrogen generation itself via Steam Methane Reforming or SMR (high temperature process that generates more than 96% of the hydrogen industrially consumed in the world). We have tackled here two primary processes that use steam to generate hydrogen, both are of relevance for reducing greenhouse gas emissions in the energy sector. The first process involves Catalytic Steam Cracking (CSC), as an upgrading process replacing hydrogen, which in my particular study is used to remove the acidity constituents in petroleum feedstocks and products. The second process involves the production of hydrogen via low-temperature steam reforming (LTSR) with gases from the previous CSC. Both processes use an in-house formulated catalyst based on Ni and Ce. Three key outcomes have ben manifested from this endeavor using this catalyst to activate steam. Firstly, the acidity constituents in petroleum feedstocks and products can be significantly reduced with a steam catalytic conversion rate of up to 83% at 380°C and 400 psig. Secondly, this LTSR approach resulted in several advantages: -a significantly reduced temperature for similar productivity of hydrogen generation - enables the process to be carried out with long-term stability. Thirdly, the LTSR process demonstrated negligible carbon monoxide production, which led to its classification as "Direct LTSR". This no need for a complementary water gas shift reaction process unit, which is currently required in industry, making it economically attractive. Detailed kinetic and isotopic studies were also carried out on both reaction systems to gain a comprehensive understanding of the underlying mechanisms and reactions involved in both steam processes. This process development confirms advances in GHG reduction, coherent with our technology’s development strategy committed with carbon dioxide abatement through catalytic processes that achieve temperature reduction and selective high-quality products.