Corrosion of Ferrous Structural Alloys in Biomass Derived Fuels and Organic Acids

Abstract

This work investigated the corrosivity of biomassderived liquid fuels and organic acids associated with bio-oils and conducted a corrosion compatibility evaluation of several structural ferrous alloys in the fuels and acids. The acidity parameters and solution conductivity values were higher in raw pyrolysis bio-oils than postprocessed oils with significant corrosion attack for carbon steel and Fe-2.25Cr-1Mo. However, higher-grade stainless steels, ferritic Fe-15Cr (15Cb) and austenitic types 304L and 316L, showed negligible corrosion loss, whereas lower-Cr ferritic grades 409, 410, and 416 were attacked. Metal leaching tests and electrochemical impedance spectroscopy measurements revealed superior corrosion resistance of 316 over 410 stainless steels in solutions of formic and oxalic acids that can be present in bio-oils. The corrosion evaluation methods utilized in this work provide effective screening tools to identify the compatible structural alloys for bio-oils.

Effect of Carboxylic Acids on Corrosion of Type 410 Stainless Steel in Pyrolysis Bio-Oil

“…Two samples of FR3 oil were subjected to KOH titrations and yielded 50.26 and 49.93 mg of KOH per gram of bio-oil. These values are significantly lower compared to some of the previously measured AMTAN values in fast pyrolysis bio-oils [30,38,39]. The observed lower AMTAN values are potentially due to the aging of the pyrolysis oils over time as described by Black and Ferrell [40].…”

“…Herein, we exposed SS410 specimens in bio-oil with varying concentrations of formic, acetic, propionic and hexanoic acids. As several conditions and specimens needed to be studied in these experiments, short-term (48 h) SS410 bio-oil exposures at 50 • C were chosen in order to provide relatively quick results about the degradation of SS410 in pyrolysis bio-oils [30].…”

“…Approximately 25-27 g of high-ash and high-moisture bio-oil, referred to as FR3 bio-oil from now on, produced by the National Renewable Energy Laboratory (Golden, CO, USA) [29] was weighed and placed into 40 mL glass vials. Further characterization of this FR3 bio-oil is described elsewhere [29,30].…”

“…Some of these compounds can be corrosive to the structural alloys that are used during the processing and storage of bio-oils [12][13][14][15][16][17]. Over the years, our team has focused on understanding the compatibility of bio-oils with structural alloys, plastics and elastomers [18][19][20][21][22][23]. Several other groups studied the corrosion effects under the combustion conditions of biomass [24,25].…”

Virtual Special Issue of Recent Advances in Biomass and Wastes Thermochemical Processing

“…The authors calculated profitability of various biorefinery designs and evaluated the impact that the introduction of a new technology could have on the development of profitable biorefinery concepts. The paper of Jun et al 15 from Oak Ridge National Laboratory reports a thorough investigation of the corrosivity of bio-oils and organic acids associated with the material of construction. The authors conducted a corrosion compatibility evaluation with several structural ferrous alloys in bio-oil-derived fuels and acids.…”