Reactivity Study of Bimetallic Fe-Mn Oxides with Addition of TiO2 for Chemical Looping Combustion Purposes

Abstract

The objective of the research was to prepare Mn-based materials for use as oxygen carriers and investigate their reactivity in terms of their applicability to energy systems. The family of Fe2O3-MnO2 with the addition of TiO2 was prepared by mechanical mixing method and calcination. Five samples with addition of Fe2O3 (20, 30, 35, and 50 wt.%) to MnO2 (65, 55, 50, 35, and 85 wt.%) with constant amount of inert TiO2 (15 wt.%) were prepared. The performance of TiO2 supported Fe-Mn oxides oxygen carriers with hydrogen/air in an innovative combustion technology known as chemical looping combustion (CLC) was evaluated. Thermogravimetric analysis was used for reactivity studies within a wide temperature range (800–1000 °C). Comprehensive characterization contained multipurpose techniques for newly synthesized materials. Moreover, post-reaction experiments considered morphology analysis by SEM, mechanical strength testing by dynamometry, and crystal phase study by XRD. Based on wide-ranging testing, the F50M35 sample was indicated as the most promising for gaseous fuel combustion via CLC at 850–900 °C temperature.

Effective direct chemical looping coal combustion using bimetallic Ti‐supported Fe2O3‐MnO2 oxygen carriers

“…Meanwhile, the lowest values were registered for the monometallic M85 sample. These results correspond well with experimental data published elsewhere 53 when gaseous fuel was combusted. Therefore, our data clearly proved that the addition of iron oxide has a beneficial influence on the oxygen transport capacity.…”

“…The formation of such a spinel was correspondingly observed in spent F50M35 samples during experiments with gaseous fuels presented in. 53 In more iron-abundant samples from F50M35 to F30M50, an Fe(III) titanate (Fe 2 TiO 5 ) was also identified, whereas in F20M65 and M85 the formation of MnTiO 3 (ICSD 44407) was recorded. The formation of manganese titanate instead of iron titanate in manganese-rich samples was also reported in.…”

“…45,52 In our previous research with 4% H 2 , we proved that manganese reached samples of Fe-Mn/Ti OCs and demonstrated great oxygen transport capabilities, even as high as 17 wt.%. 53 Although, some Fe-Mn/Ti mixed systems were tested for biomass combustion, 32,43,45 the materials presented in this work contain higher titanium (15%) and manganese (up to 85%) amounts and are applied in this case for potential coal combustion processes.…”

“…54 The calculated theoretical oxygen transport capabilities for the family were shown in a previous work. 53 The examined sample, composed of 200 mg of fuel and OC, was heated in an argon atmosphere at a heating rate of 15K/min to the desired temperature (900, 950 or 1,000°C); when this temperature was reached, isothermal measurements were performed for 120 min. The OC regeneration stage was set up for 20 min with a synthetic airflow rate of 80 ml/min.…”

Actual Trends in the Usability of Biochar as a High-Value Product of Biomass Obtained through Pyrolysis

“…There are four main Carbon Capture methods, pre-combustion capture, post-combustion capture [37], oxyfuel combustion [38], and chemical looping combustion [39]. Chemical methods are based either on adsorption or absorption; physical methods, including membrane filtration or chemical looping combustion, enhance oil and gas recovery; and biological mitigation through terrestrial plants, and algae are all common CO 2 management techniques.…”