Molten chloride salt pyrolysis of biomass: Effects of temperature and mass ratio of molten salt to biomass

Mujahid Ali, Faisal Mahmood, Christian Fabrice Magoua Mbeugang, Jiazhen Tang, Xing Xie and Bin Li

Energy, 2025, vol. 316, issue C

Abstract: Molten salt pyrolysis of biomass can effectively solve the heat supply/transfer bottleneck issue during biomass pyrolysis and simultaneously produce value-added products. This study aims to explore the influences of temperature (500–800 °C) and mass ratio of molten salt to biomass (MS:B, i.e., 0:1, 10:1, and 15:1) on the molten chloride salts (ZnCl2-NaCl-KCl) pyrolysis of pine sawdust. It was found that ZnCl2-NaCl-KCl significantly enhanced dehydrogenation and decarboxylation reactions, yielding high contents of H2 (41.52–54.58 vol%) and CO2 in non-condensable gas. The biochar yield from molten chloride salts pyrolysis was nearly doubled possibly due to enhanced dehydration and dehydrogenation/condensation by ZnCl2 in the salts at all testing temperatures. A highly porous biochar with a BET surface area of 738.38 m2/g could be directly obtained from molten chloride salts pyrolysis at lower temperature of 500 °C with a MS:B of 10:1. The molten chloride salts altered the reaction pathway of pine sawdust pyrolysis, leading to a significantly different bio-oil composition. A high content of linear carbonyls of 93.95 % was detected in bio-oil with MS:B of 10:1 at 500 °C due to the high alkali metal ions facilitating the ring opening/scission of sugar units. While temperature increasing promoted linear carbonyls/acids undergo decarbonylation, decarboxylation and further dehydrogenation/aromatization, a high content of phenols and aromatics of 83.21 % was obtained with MS:B of 15:1 at 800 °C. This study shows a prospect to directly produce a H2-rich gas, a porous biochar, and a high selectivity bio-oil through a one-step method of molten chloride salts pyrolysis of biomass.

Keywords: Biomass pyrolysis; Molten chloride salt; ZnCl2-KCl-NaCl; H2-rich gas; Porous biochar; Bio-oil (search for similar items in EconPapers)
Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0360544225002762
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:energy:v:316:y:2025:i:c:s0360544225002762

DOI: 10.1016/j.energy.2025.134634

Access Statistics for this article

Energy is currently edited by Henrik Lund and Mark J. Kaiser

More articles in Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().