Manganese ores as oxygen carriers for chemical-looping combustion (CLC) and chemical-looping with oxygen uncoupling (CLOU)
Journal article, 2017

Manganese-based oxygen carriers can be used in chemical-looping combustion (CLC) and chemical-looping with oxygen uncoupling (CLOU). This paper expands on a previous investigation into manganese ores as oxygen carriers for CLC. The paper presents reactivity data for eight ores with widely different compositions. Most importantly, the ores contained significant quantities of Fe, Si, and Ca, with Fe/Mn and Si/Mn molar ratios that varied between 0.1-4.5 and 0.07-0.48, respectively. Pre-treatment of the ores consisted of heat treatment in air at 950 °C for 24 h followed by sieving to obtain a particle size fraction of 125-180 ?m. Reactivity towards methane and synthesis gas (50 vol% CO in H2) and the oxygen uncoupling behaviour at 900, 950, and 1000 °C was investigated in a fluidized batch reactor. Material characterization of the ores included an attrition test, crushing strength, and BET surface area measurement. The oxygen carriers had a CO2 yield of 31-80% for syngas with 2 g of oxygen carriers using 450 ml/min of syngas. The performance for all ores as a function of number of cycles was stable. By using a pseudo-first-order rate constant, apparent activation energies were calculated at ? = 0.999 and 0.99 for methane and syngas, respectively, and the apparent activation energies varied in a wide range, from 110 to 328 kJ/mol for CH4 and 10 to 168 kJ/mol for CO. The attrition resistance of the particles was measured using a jet cup attrition rig. The findings indicate that a higher reactivity is associated with higher attrition, however, there is no direct correlation between the two.

Chemical looping with oxygen uncoupling

Oxygen carrier

Carbon capture

Chemical looping combustion

Manganese ore

Author

Sebastian Sundqvist

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Nazli Khalilian

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Henrik Leion

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Tobias Mattisson

Chalmers, Energy and Environment, Energy Technology

Anders Lyngfelt

Chalmers, Energy and Environment, Energy Technology

Journal of Environmental Chemical Engineering

2213-2929 (ISSN) 2213-3437 (eISSN)

Vol. 5 3 2552-2563

Subject Categories

Chemical Sciences

DOI

10.1016/j.jece.2017.05.007

More information

Latest update

2/19/2021