Activating dinitrogen for chemical looping ammonia synthesis: nitridation of manganese

Aframehr, Wrya Mohammadi; Pfromm, Peter H.

doi:10.1007/s10853-021-06079-7

Cited by 15 publications

(21 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1. The experimental setup was used as shown and described in our previous publication (Aframehr and Pfromm, 2021). A digital flow controller (Teledyne Hastings Instruments HFC-D-302B(H), Teledyne Hastings, Hampton, VA, U.S.A.) was used to control gas flow, in addition, a bubble flowmeter was used to check the flow.…”

Section: Methodsmentioning

confidence: 99%

“…Heat up and cool down are described by Eq. ( 1) and ( 2) respectively (tube furnace nitridation procedure shown in our previous work (Aframehr and Pfromm, 2021)).…”

Section: Methodsmentioning

confidence: 99%

“…An alternative method to produce NH 3 at atmospheric pressure and elevated temperature is chemical looping ammonia synthesis (CLAS). As reported elsewhere (Aframehr et al, 2020;Aframehr and Pfromm, 2021) this method consists of converting the bulk of a fixed bed of solid manganese (Mn) particles to Mn nitrides by contacting with N 2 gas at atmospheric pressure and elevated temperature. Then by switching the gas from N 2 to H 2 over the nitrided Mn, NH 3 is produced at atmospheric pressure and elevated temperature.…”

Section: Introductionmentioning

confidence: 99%

“…In our previous study, a two-step chemical looping process operating under relatively mild conditions to produce NH 3 was studied regarding Mn nitride phases and the particle surface morphology and composition (Aframehr et al, 2020). The time and temperature dependencies of Mn nitride layer growth and diffusion zone growth (microstructural development) during nitridation were investigated (Aframehr and Pfromm, 2021). The work presented here extends previous studies towards examining the non-steady state nitridation process as an N diffusion/reaction process and mathematical modeling of Mn nitride layer formation.…”

Section: Introductionmentioning

confidence: 99%

“…The overall goal of this work is to contribute to the understanding and quantification of non-steady state nitride formation from solid Mn and gaseous N 2 via splitting of N 2 at the gas/solid interface, followed by simultaneous diffusion of N atoms into the solid and reaction with Mn. This is the first step in a chemical looping approach to synthesize NH 3 by subsequently contacting Mn nitride with gaseous H 2 (Aframehr et al, 2020;Aframehr and Pfromm, 2021). This looping NH 3 synthesis process is quite unique in that N atoms emanating from the bulk nitride react with hydrogen from the gas phase at the solid/gas interface.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Activating dinitrogen for chemical looping ammonia Synthesis: Mn nitride layer growth modeling

Aframehr

Pfromm

2022

Chemical Engineering Science

Self Cite

View full text Add to dashboard Cite

Section: Methodsmentioning

confidence: 99%

“…Heat up and cool down are described by Eq. ( 1) and ( 2) respectively (tube furnace nitridation procedure shown in our previous work (Aframehr and Pfromm, 2021)).…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Activating dinitrogen for chemical looping ammonia Synthesis: Mn nitride layer growth modeling

Aframehr

Pfromm

2022

Chemical Engineering Science

Self Cite

View full text Add to dashboard Cite

Chemical Looping Technology in Mild‐Condition Ammonia Production: A Comprehensive Review and Analysis

Fu,

Gong,

Wang

et al. 2023

Small

View full text Add to dashboard Cite

Ammonia is an efficient and clean hydrogen carrier that promises to tackle the increasing energy and environmental problems. However, more than 90% of ammonia is produced by the Haber–Bosch process, and its enormous energy consumption and CO2 emissions require the development of novel alternatives. Chemical looping technology can decouple the one‐step ammonia synthesis reaction into separated nitridation and hydrogenation processes at atmospheric pressure, thereby achieving the mild ammonia synthesis based on renewable energy. The strategy of stepwise reactions circumvents the problem of competing adsorption of N2 and H2/H2O at the active sites and provides additive freedom for optimal regulation of sub‐reactions. This review introduces the concept and mechanism of chemical looping ammonia production (CLAP), and comprehensively summarizes the state‐of‐art research from the perspective of reaction pathways and nitrogen carriers. The challenges faced by CLAP and strategies to address them in terms of nitrogen carriers, methods, equipment, and technological processes are also proposed.

show abstract

Metal nitrides as electrocatalysts in green ammonia synthesis

Januszewska-Kubsik,

Podsiadło,

Pudełko

et al. 2024

Appl. Phys. A

View full text Add to dashboard Cite

Green ammonia is assumed to be an important part of the European hydrogen economy and one of the most important substrates of chemical industry. The future development of its manufacturing processes can be related to the electrocatalytic studies yielding in the development of the catalytic materials that would effectively break the nitrogen-nitrogen bond to successfully drive the N2RR—a process of molecular nitrogen electroreduction to ammonia. Molecular nitrogen is characterized with strong triple bond energies (942 kJ/mol) which leading into large dissociation energy of N2 (9,76 eV) and also large energy barrier of the first step of triple bond dissociation 410 kJ/mol (4,25 eV). Those large energies makes reduction to ammonia an extremely difficult task. Metal nitrides of d and f block became in interest due to their activity in ammonia production from molecular nitrogen and hydrogen. Practically all the transition elements occurs in one of the four types of crystalline structures: regular, regular face cantered, hexagonal and hexagonal close packed. The reactions of these metals with nitrogen (or ammonia) typically yields in nitride compounds of an identical type of crystalline structure as the initial metal. Dealing with single metal systems, their ternary counterparts and metal–metal nitride heterostructures, the presented review shows that nitrides are promising groups of electrocatalytic materials. Being property-prone to their internal structural features such as non-stoichiometry and correlated concentration of nitrogen vacancies, metal nitrides are a good candidate for joined investigations spanned between electrochemistry, inorganic chemistry and material engineering.

show abstract

Activating dinitrogen for chemical looping ammonia synthesis: nitridation of manganese

Cited by 15 publications

References 37 publications

Activating dinitrogen for chemical looping ammonia Synthesis: Mn nitride layer growth modeling

Activating dinitrogen for chemical looping ammonia Synthesis: Mn nitride layer growth modeling

Chemical Looping Technology in Mild‐Condition Ammonia Production: A Comprehensive Review and Analysis

Metal nitrides as electrocatalysts in green ammonia synthesis

Contact Info

Product

Resources

About