Projeto Portugal 2030

Sumário

We aim to provide a new concept in synthetic chemical and fuel production from the sustainable recycling of CO2. Breaking with convention, we target the construction, testing, simulation and life cycle assessment of a disruptive electrochemically driven device for CO2 hydrogenation that simultaneously offers in-situ steam electrolysis, Fig.1. We focus our research on the stage after CO2 capture, where we aim to overcome current limitations in state-of-the-art direct CO2 hydrogenation by Fischer Tropsch (FT) synthesis, circumventing both performance and economic issues by the current concept. Pioneering information will be obtained through materials engineering, device construction and a detailed electrocatalytic study. Simulation studies built on kinetic parameter estimation, energy and mass balance of these results will permit identification of best methods for system integration, operation conditions and energy balance, while global market feasibility will be assessed by energy and emissions analysis from a life cycle perspective, involving dynamic Life Cycle Impact Assessment (LCIA) and Life Cycle Cost Assessment (LCCA). These goals are highly multidisciplinary, bridging materials engineering, chemical kinetics, electrochemistry and mechanical engineering. Specific objectives are therefore: 1) To fabricate functional microtubular reactors for electrochemical FT synthesis, Fig.1, formed from proton conducting ceramic membranes. Target values: performance single cell, electrode polarisation losses <2 Ohmcm2 at current densities 1 Acm-2, electrolyte Area Specific Resistance (ASR) <2 Ohmcm2, @ 400ºC 2) To provide proof of concept of the device of, Fig 1, raising its TRL from 2-4 within the timeframe of the proposal. In this concept, in-situ steam dissociation permits the formation of protons, which are then directly introduced into the FT reactor by electrochemical pumping, thereby, providing a controlled H/C ratio along the reactor length to promote formation of longer chain hydrocarbons C2-C5+ (C5+ indicates the start of liquid fuel products). Here key performance targets are, temperature range of operation, 350-400ºC, pressure 1-10bar, methane production <15%, selectivity to long chain (C5+) over that of shorter C2-4 hydrocarbons >40%, current efficiencies >60%, to exceed the state of the art 3) To assess alterations in CO2-FT product distribution by the new concept of H2 pumping and to perform simulation studies built on kinetic parameter estimation, energy and mass balance of the experimental results to identify best methods for system integration, operation conditions and energy balance. In this objective we also aim to provide an unprecedented understanding of the effect of electrochemical pumping on the rate limiting mechanisms of CO2-FT synthesis. 4) To perform an energy and emissions analysis from a life cycle perspective using this data to provide the environmental flows of each potential hydrocarbon product, their contribution to climate change, primary energy use, and human health. Here dynamic Life cycle impact assessment (LCIA) will analyze the impact categories of cumulative energy demand, global warming potential, ozone depletion, acidification, eutrophication, human toxicity and particulate matter formation, while Life Cycle Cost Assessment (LCCA) will consider the materials cost variation and environmental impacts as a function of the product range and method, compared to traditional multistep processes