Thermochemical H2O and CO2 splitting redox cycles in a NiFe2O4 structured redox reactor: Design, development and experiments in a high flux solar simulator

Abstract

A high flux solar simulator allows the lab-scale assessment of solar reactor concepts by irradiating a target with high flux thermal energy, similarly to reactors installed in concentrated solar radiation facilities such as central towers with a heliostat field. In the current study, the design and construction of a high flux solar simulator facility for near realistic solar experiments is presented. A simple, cavity-tubular thermochemical reactor is employed for the evaluation of the redox activity of structured monolithic bodies (foams and honeycombs) consisting entirely of NiFe 2 O 4 w.r.tÁH 2 O splitting, CO 2 splitting and combined H 2 O-CO 2 splitting reactions. Experiments under realistic conditions, i.e. a solar reactor under irradiation, were conducted to assess the solar fuels production capability, which was examined at the structure level and the reactor level. The best performing structure was the NiFe 2 O 4 foam. Further multilevel research (structure, reactor as well as redox material), will improve product yield and reactor efficiency.

Syngas Production Through H2O/CO2 Thermochemical Splitting Over Doped Ceria-Zirconia Materials

“…While a huge amount of literature has been devoted to the thermochemical splitting of bare H 2 O or CO 2 , little is known about their simultaneous splitting (Furler et al, 2012;Lorentzou et al, 2014Lorentzou et al, , 2017Falter and Pitz-Paal, 2018;de la Calle and Bayon, 2019;Tou et al, 2019;Hao et al, 2020). It is worth noting that co-splitting has been generally defined as concurrent or combined splitting, but it should be better defined as competitive splitting; as a matter of fact, CO 2 and H 2 O compete for the same reduced sites, whereas the overall fuel production depends on the reduction extent of the material.…”

Nanoscale zero‐valent Ni–Fe alloy catalyst featuring a dual galvanic effect to promote formate formation by CO2 hydrogenation

“…In order to convert the available huge amount of carbon source into value-added chemical products, a variety of processes have been researched, for instance, photo-catalytic reduction, 1 electrochemical reduction, 2 photo-electrochemical reduction, 3 catalytic hydrogenation 4 , and thermo-chemical synthesis. 5 Among these methods for CO 2 resource utilization, CO 2 is efficiently converted into diverse products, such as methane, 6 methanol 7 , and formic acid, 8 by catalytic hydrogenation, which requires no additional technical aids, for instance, light, electric, and heat. However, further improvement still deserves to be accomplished for this promising technology due to the reaction conditions of high temperature and high pressure.…”

Hλιοθερμοχημικοί Αντιδραστήρες Για Παραγωγή Καυσίμων Με Ουδέτερο Αποτύπωμα Άνθρακα

“…The solar simulator facility (figure 3.1, [73]) is a highly complex lab device consisting of different components and subsystems. In the next paragraphs the most important components are described, in terms of design and manufacturing.…”

“…Based on the aforementioned considerations, the reactor concept developed and employed for the redox thermochemical H 2 O and CO 2 splitting reactions in the solar simulator facility is a tubular configuration with a cavity [73]. The core component of the reactor is the redox material (in the current work NiFe 2 O 4 ), which is shaped into different monolithic structures and indirectly heated.…”

“…Three different structures (foam, extruded honeycomb monolith, cast monolith), consisting entirely of NiFe 2 O 4 , were evaluated in the tubular reactor installed in the high flux solar simulator [73]. Details on the synthesis and manufacturing techniques and physical characteristics of the various structures are described in detail in [69] and are presented here only briefly for completeness:…”