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Cited by 92Thermochemical Biomass Conversion ProcessesAdsorption and biosorption for pollutant removalSoil Carbon and Nitrogen Dynamics

Impact of Biomass Source and Pyrolysis Parameters on Physicochemical Properties of Biochar Manufactured for Innovative Applications

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Uroić Štefanko, Ana, Leszczynska, Danuta·2020·Frontiers in Energy Research
DOI 10.3389/fenrg.2020.00138
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Abstract

Biochar production for energy and high-tech applications requires a specific set of physicochemical parameters based on interfaces between initial pyrolytic conditions and properties of starting material, namely biomass. This study compares 20 types of biochar produced from five diverse waste biomasses at two pyrolytic temperatures (400°C, 700°C), processing times (2 h, 5 h) and heating rates (26°C/min, 5°C/min). The manufactured biochar was tested for the yield, fixed C, ash load, size of developed surface area, porosity, nutrients, and minerals. Leachate tests were performed to determine the stability of biochar, their pH, conductivity, and presence of dissolved nutrients. The proximate analysis demonstrated an increase in fixed C linked to temperature increase from 400°C to 700°C. Biochar produced from organic-rich biomass such as corn stover, showed higher content of nutrients, especially potassium and phosphorus on their surfaces and in their leachates, which influenced the development of its surfaces at 700°C. The increase of temperature with prolonged residence time has generated more stable and mostly aromatic structures within biochar when compared to other studied conditions. These findings were confirmed by the FTIR spectra that indicated amplified condensation of aromatic and aliphatic carbons (C=C, C=O, C-H) and a decrease of phenolic bonded water (-OH bonded). Consequently, a specific application of biochar should ultimately dictate the choice of optimal pyrolytic conditions and original/added components of initial biomass.

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  • Fouling is partly mitigated by CRD wood's low S, N, and P content, which reduces the formation of corrosive acidic species above 700°C.

    “Fouling, driven by K and Na volatilization and subsequent alkali chloride/sulphide/phosphide condensation on reactor surfaces, is partly mitigated by CRD wood's low S, N, and P content, which reduces the formation of corrosive acidic species above 700 • C [84][85][86][87].”

    From Pilot-Scale Slow Pyrolysis, Post-Heat Treatment, and Self-Heating Performance of Biochar Fuels Derived from Construction, Renovation, and Demolition (CRD) Wood Waste (2026) · cites this paper as [86]

    The Biomass Selection and Pretreatment section lists the feedstocks studied but does not include CRD wood. The Biochar pH and EC and Biochar Yield and Proximate Analysis sections discuss acidity and potassium volatilization, but do not address fouling mitigation, low S/N/P content, or reduced corrosive acidic species above 700°C. Searches for those terms and for alkali deposits found no supporting passage; page numbers were unavailable. (LLM, conf=0.76)

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Cited by

Sorted by citations

Authors
Uroić Štefanko, A., & Leszczynska, D.
Venue
Frontiers in Energy Research
Publisher
Frontiers Media SA
Published
2020-07-16
Volume
8
ISSN
2296-598X (ISSN-L)
DOI
10.3389/fenrg.2020.00138
OpenAlex
W3042642752
Cited by
92
References
8
Citations by year
2026: 25 · 2025: 22 · 2024: 19 · 2023: 9 · 2022: 10 · 2021: 7
FWCI
2.04
Type
journal article
Language
en
Open access
Licence
Locations
  • Frontiers in Energy Research (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • National Science Foundation (1632899, 1547754)
  • U.S. Department of Transportation (69A3551747130, Grant Award Number 69A3551747130)
  • Core Research for Evolutional Science and Technology (HRD 1547754)
  • Office of Experimental Program to Stimulate Competitive Research (1632899, OIA-1632899)
Topics
  • Physical Sciences › Engineering › Biomedical Engineering › Thermochemical Biomass Conversion Processes
  • Physical Sciences › Environmental Science › Water Science and Technology › Adsorption and biosorption for pollutant removal
  • Life Sciences › Agricultural and Biological Sciences › Soil Science › Soil Carbon and Nitrogen Dynamics
Keywords
biochar, pyrolysis parameters, biomass sources, biomass waste, pyrolysis temperature, heating rate, residence time, biochar yield, fixed carbon, ash content, surface area, porosity, nutrient content, mineral content, corn stover, aromatic structure, biochar amendment

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