Publication detail

A two-step thermochemolysis for Soil Organic Matter analysis. Application to lipid-free organic fraction and humic substances from an ombrotrophic peatland.

ESTOURNEL-PELARDY, C. EL-MUFLEH AL HUSSEINI, A. DOSKOČIL, L. GRASSET, L.

Original Title

A two-step thermochemolysis for Soil Organic Matter analysis. Application to lipid-free organic fraction and humic substances from an ombrotrophic peatland.

English Title

A two-step thermochemolysis for Soil Organic Matter analysis. Application to lipid-free organic fraction and humic substances from an ombrotrophic peatland.

Type

journal article

Language

en

Original Abstract

A two-step off-line thermochemolysis was developed to characterize successively free and bound compounds in humic fractions. Two reactants with different strengths were used: hexamethyldisilazane (HMDS) followed by tetramethylammonium hydroxide (TMAH). Analysis of the thermolysates showed obvious differences between the two steps regarding the nature and/or the distribution of the numerous identified products. The first step with HMDS revealed the occurrence of thermolabile compounds and/or molecular units occurring initially in (bio)polymers susceptible to be cracked by HMDS, mostly carbohydrates and aromatics. The second step with TMAH released products resulting from the cracking of units with a relatively high thermal and/or chemical stability (monomers from biopolymers such as lignin and cutins, suberins or waxes). Two-step thermochemolysis thus appears as an interesting tool to help deciphering the composition, origin and nature of soil and sediment organic matter. Moreover, the comparison of the three humic substances fractions (fulvic acids, humic acids and humin) shows that a part of the analysed compounds (lipids, aromatic and carbohydrates) were lost during this chemical fractionation.

English abstract

A two-step off-line thermochemolysis was developed to characterize successively free and bound compounds in humic fractions. Two reactants with different strengths were used: hexamethyldisilazane (HMDS) followed by tetramethylammonium hydroxide (TMAH). Analysis of the thermolysates showed obvious differences between the two steps regarding the nature and/or the distribution of the numerous identified products. The first step with HMDS revealed the occurrence of thermolabile compounds and/or molecular units occurring initially in (bio)polymers susceptible to be cracked by HMDS, mostly carbohydrates and aromatics. The second step with TMAH released products resulting from the cracking of units with a relatively high thermal and/or chemical stability (monomers from biopolymers such as lignin and cutins, suberins or waxes). Two-step thermochemolysis thus appears as an interesting tool to help deciphering the composition, origin and nature of soil and sediment organic matter. Moreover, the comparison of the three humic substances fractions (fulvic acids, humic acids and humin) shows that a part of the analysed compounds (lipids, aromatic and carbohydrates) were lost during this chemical fractionation.

Keywords

Thermochemolysis, two-step method, HMDS, TMAH, soil organic matter

RIV year

2013

Released

13.09.2013

Pages from

103

Pages to

110

Pages count

8

BibTex


@article{BUT101618,
  author="Céline {Estournel-Pelardy} and Amelène {El-Mufleh Al Husseini} and Leoš {Doskočil} and Laurent {Grasset}",
  title="A two-step thermochemolysis for Soil Organic Matter analysis. Application to lipid-free organic fraction and humic substances from an ombrotrophic peatland.",
  annote="A two-step off-line thermochemolysis was developed to characterize successively free and bound compounds in humic fractions. Two reactants with different strengths were used: hexamethyldisilazane (HMDS) followed by tetramethylammonium hydroxide (TMAH). Analysis of the thermolysates showed obvious differences between the two steps regarding the nature and/or the distribution of the numerous identified products. The first step with HMDS revealed the occurrence of thermolabile compounds and/or molecular units occurring initially in (bio)polymers susceptible to be cracked by HMDS, mostly carbohydrates and aromatics. The second step with TMAH released products resulting from the cracking of units with a relatively high thermal and/or chemical stability (monomers from biopolymers such as lignin and cutins, suberins or waxes). Two-step thermochemolysis thus appears as an interesting tool to help deciphering the composition, origin and nature of soil and sediment organic matter. Moreover, the comparison of the three humic substances fractions (fulvic acids, humic acids and humin) shows that a part of the analysed compounds (lipids, aromatic and carbohydrates) were lost during this chemical fractionation.",
  chapter="101618",
  doi="10.1016/j.jaap.2013.09.001",
  number="11",
  volume="104",
  year="2013",
  month="september",
  pages="103--110",
  type="journal article"
}