Chemical methods for determining the electron storage capacity of black carbon

Electron storage capacity (ESC) is a new and important property that determines the capacity of a black carbon to mediate abiotic and microbial electron transfer reactions in natural and engineered systems. It is necessary to develop accurate and reproducible methods to measure black carbon's ESC in order to understand its redox behavior and to predict its capacity to support redox transformation of contaminants in subsurface environments. In this study, we developed chemical methods that employed combinations of reductants and oxidants of different redox potentials - Ti(III) citrate or dithionite as reductant, and ferricyanide or dissolved O2 as oxidant - to measure the ESC of a wood-derived biochar. Pore diffusion within biochar particles was rate-limiting and controlled the timescale for redox equilibrium and ESC measurements. •The new methods can handle sample mass on the order of a gram•Sample pretreatment (e.g., oxidation via aeration) is necessary to produce consistent results•For a given reductant-oxidant pair, colorimetric (or potentiometric) measurements gave constant and reproducible ESC.

Medienart:

E-Artikel

Erscheinungsjahr:

2018

Erschienen:

2018

Enthalten in:

Zur Gesamtaufnahme - volume:5

Enthalten in:

MethodsX - 5(2018) vom: 28., Seite 1515-1520

Sprache:

Englisch

Beteiligte Personen:

Xin, Danhui [VerfasserIn]
Xian, Minghan [VerfasserIn]
Chiu, Pei C [VerfasserIn]

Links:

Volltext

Themen:

Biochar
Black carbon
Chemical method
Chemical oxidation/reduction
Electron accepting capacity
Electron donating capacity
Electron storage capacity
Journal Article
Redox reversibility

Anmerkungen:

Date Revised 01.10.2020

published: Electronic-eCollection

Citation Status PubMed-not-MEDLINE

doi:

10.1016/j.mex.2018.11.007

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM291500846