Preliminary Screening of Materials for the Chemical Looping CO₂ Splitting Process as a Pathway for Biokerosene Synthesis

Abstract

The EU Green Deal aims to achieve climate neutrality by 2050. This means a transition from fossil fuels to renewable energy sources. In the aviation sector, this paradigm shift will require a long period of time so that one of the best shortterm options is the synthesis of biokerosene. However, the production of synthetic kerosene suffers currently from low efficiency and high costs. To reduce the cost and enhance the yield of this process, a promising option is Chemical Looping CO 2 Splitting technology, which converts CO 2 into CO, providing together with green H 2 the raw materials for the aviation biofuel production process chain through the Fischer−Tropsch synthesis.A key aspect for the deployment of chemical looping CO 2 splitting technology lies in developing suitable oxygen carriers. In this work, a preliminary screening of 18 Fe-based materials with a wide variety of supports (CaAl 2 O 4 , MgAl 2 O 4 , Zr-doped hydrotalcites, CaO, MgO, ZrO 2 , SiO 2 , and TiO 2 ) was carried out evaluating their physicochemical properties (mechanical resistance, reactivity and redox conversion) by means of crushing strength and thermogravimetric analysis tests. On the basis of these properties, the most promising oxygen carriers to be used in a Chemical Looping CO 2 Splitting system were selected. The best candidates were those prepared by the mechanical mixing method using Zr-doped synthetic hydrotalcite, ZrO 2 , Mg-doped ZrO 2 , SiO 2 /ZrO 2 (50:50), and Mg-doped TiO 2 as supports.