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Title: Purification strategy and effect of impurities on corrosivity of dehydrated carnallite for thermal solar applications

Abstract

This paper presents a purification method for dehydrated carnallite (DC)—a commercial ternary MgCl2–KCl–NaCl salt—for concentrating solar power (CSP) applications based on a thermal and chemical treatment using the reduction power of Mg. The purification is effective at reducing MgOH+ by an order of magnitude—from around 5 wt% in non-treated salt to less than 0.5 wt% in post-purification salt. The corresponding decrease in the measured corrosion rate of Haynes 230 at 800 °C from >3200 μm per year to around 40 μm per year indicates that soluble MgOH+ is indeed correlated to corrosion. The addition of elemental Mg serves as both a scavenger of impurities and corrosion potential control, which are considered the primary mechanisms for corrosion mitigation.

Authors:
ORCiD logo [1];  [1];  [1]
  1. National Renewable Energy Laboratory, Golden, USA
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
OSTI Identifier:
1579461
Alternate Identifier(s):
OSTI ID: 1593687
Report Number(s):
NREL/JA-5500-75487
Journal ID: ISSN 2046-2069; RSCACL
Grant/Contract Number:  
AC36-08GO28308
Resource Type:
Published Article
Journal Name:
RSC Advances
Additional Journal Information:
Journal Name: RSC Advances Journal Volume: 9 Journal Issue: 71; Journal ID: ISSN 2046-2069
Publisher:
Royal Society of Chemistry
Country of Publication:
United Kingdom
Language:
English
Subject:
14 SOLAR ENERGY; 47 OTHER INSTRUMENTATION; CSP; solar; carnallite

Citation Formats

Zhao, Youyang, Klammer, Noah, and Vidal, Judith. Purification strategy and effect of impurities on corrosivity of dehydrated carnallite for thermal solar applications. United Kingdom: N. p., 2019. Web. doi:10.1039/C9RA09352D.
Zhao, Youyang, Klammer, Noah, & Vidal, Judith. Purification strategy and effect of impurities on corrosivity of dehydrated carnallite for thermal solar applications. United Kingdom. doi:https://doi.org/10.1039/C9RA09352D
Zhao, Youyang, Klammer, Noah, and Vidal, Judith. Mon . "Purification strategy and effect of impurities on corrosivity of dehydrated carnallite for thermal solar applications". United Kingdom. doi:https://doi.org/10.1039/C9RA09352D.
@article{osti_1579461,
title = {Purification strategy and effect of impurities on corrosivity of dehydrated carnallite for thermal solar applications},
author = {Zhao, Youyang and Klammer, Noah and Vidal, Judith},
abstractNote = {This paper presents a purification method for dehydrated carnallite (DC)—a commercial ternary MgCl2–KCl–NaCl salt—for concentrating solar power (CSP) applications based on a thermal and chemical treatment using the reduction power of Mg. The purification is effective at reducing MgOH+ by an order of magnitude—from around 5 wt% in non-treated salt to less than 0.5 wt% in post-purification salt. The corresponding decrease in the measured corrosion rate of Haynes 230 at 800 °C from >3200 μm per year to around 40 μm per year indicates that soluble MgOH+ is indeed correlated to corrosion. The addition of elemental Mg serves as both a scavenger of impurities and corrosion potential control, which are considered the primary mechanisms for corrosion mitigation.},
doi = {10.1039/C9RA09352D},
journal = {RSC Advances},
number = 71,
volume = 9,
place = {United Kingdom},
year = {2019},
month = {12}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
DOI: https://doi.org/10.1039/C9RA09352D

Citation Metrics:
Cited by: 2 works
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Works referenced in this record:

Preparation of MgOHCl by controlled dehydration of MgCl2·6H2O
journal, April 2004

  • Kashani-Nejad, S.; Ng, K. W.; Harris, R.
  • Metallurgical and Materials Transactions B, Vol. 35, Issue 2
  • DOI: 10.1007/s11663-004-0042-4

MgOHCl thermal decomposition kinetics
journal, February 2005

  • Kashani-Nejad, S.; Ng, K. -W.; Harris, R.
  • Metallurgical and Materials Transactions B, Vol. 36, Issue 1
  • DOI: 10.1007/s11663-005-0015-2

Corrosion behavior of metallic alloys in molten chloride salts for thermal energy storage in concentrated solar power plants: A review
journal, September 2018

  • Ding, Wenjin; Bonk, Alexander; Bauer, Thomas
  • Frontiers of Chemical Science and Engineering, Vol. 12, Issue 3
  • DOI: 10.1007/s11705-018-1720-0

FactSage thermochemical software and databases, 2010–2016
journal, September 2016


Thermal decomposition mechanisms of MgCl2·6H2O and MgCl2·H2O
journal, May 2011

  • Huang, Qiongzhu; Lu, Guimin; Wang, Jin
  • Journal of Analytical and Applied Pyrolysis, Vol. 91, Issue 1
  • DOI: 10.1016/j.jaap.2011.02.005

Dimensionless Analysis for Predicting Fe-Ni-Cr Alloy Corrosion in Molten Salt Systems for Concentrated Solar Power Systems
journal, June 2016

  • Cho, Hyun-Seok; Van Zee, J. W.; Shimpalee, Sirivatch
  • Corrosion, Vol. 72, Issue 6
  • DOI: 10.5006/1865

Corrosion behavior of 316SS and Ni-based alloys in a ternary NaCl-KCl-MgCl2 molten salt
journal, September 2018


Thermal decomposition studies on magnesium hydroxychlorides
journal, October 2012


Multidimensional Modeling of Nickel Alloy Corrosion inside High Temperature Molten Salt Systems
journal, January 2016

  • Mehrabadi, Bahareh Alsadat Tavakoli; Weidner, John W.; Garcia-Diaz, Brenda
  • Journal of The Electrochemical Society, Vol. 163, Issue 14
  • DOI: 10.1149/2.0411614jes

Solubility of magnesium oxide in molten salts
journal, January 1962


Mechanism and Kinetics of Thermal Decomposition of MgCl2 × 6H2O
journal, June 2010

  • Huang, Qiong-Zhu; Lu, Gui-Min; Wang, Jin
  • Metallurgical and Materials Transactions B, Vol. 41, Issue 5
  • DOI: 10.1007/s11663-010-9390-4

Electrochemical measurement of corrosive impurities in molten chlorides for thermal energy storage
journal, February 2018


Preparation of MgO nanocrystals and catalytic mechanism on phenol ozonation
journal, January 2017

  • Wang, Bing; Xiong, Xingaoyuan; Ren, Hongyang
  • RSC Advances, Vol. 7, Issue 69
  • DOI: 10.1039/C7RA07553G

A thermochemical analysis of the production of anhydrous MgCl2
journal, May 2001


Molten chloride salts for next generation concentrated solar power plants: Mitigation strategies against corrosion of structural materials
journal, May 2019


The Solubility of MgO in Molten MgCl<SUB>2</SUB>-CaCl<SUB>2</SUB> Salt
journal, January 2004


Hydration and dehydration of salt hydrates and hydroxides for thermal energy storage - kinetics and energy release
journal, January 2012


The thermal decomposition of magnesium chloride dihydrate
journal, February 1989


Preparation of anhydrous magnesium chloride from ammonium magnesium chloride hexahydrate
journal, March 2010

  • Eom, Hyoung-Choon; Park, Hyungkyu; Yoon, Ho-Sung
  • Advanced Powder Technology, Vol. 21, Issue 2
  • DOI: 10.1016/j.apt.2010.01.003

Modeling the Effect of Cathodic Protection on Superalloys Inside High Temperature Molten Salt Systems
journal, January 2017

  • Mehrabadi, Bahareh Alsadat Tavakoli; Weidner, John W.; Garcia-Diaz, Brenda
  • Journal of The Electrochemical Society, Vol. 164, Issue 4
  • DOI: 10.1149/2.1461704jes